Low handgrip strength is closely associated with anemia among adults: A cross-sectional study using Korea National Health and Nutrition Examination Survey (KNHANES)

Yu-mi Gi; Boyoung Jung; Koh-Woon Kim; Jae-Heung Cho; In-Hyuk Ha

doi:10.1371/journal.pone.0218058

Abstract

Background

Anemia, which is a major public health problem worldwide, represents a decline in the oxygenation function, and can therefore be related to low strength. However, hemoglobin cannot repair muscles directly, but is beneficial only in a supportive role. Previous studies on the relationship between handgrip strength and anemia have been controversial. Thus, we aimed to analyze the association between handgrip strength and anemia in Korean adults.

Methods

This cross-sectional study used the 2013–2017 data from the 6th and 7^th Korean National Health and Nutrition Examination Survey (KNHANES) that included 16,638 Korean adults, aged ≥19 years, who met the inclusion or exclusion criteria. Differences in sociodemographic factors (sex, age, education, income, and employment), lifestyle factors (alcohol consumption, smoking, and physical activity), and illness and health factors [body mass index (BMI), vitamin intake, iron intake, comorbid illnesses, and handgrip strength] by existence of anemia, were analyzed using the Chi square test. Binary logistic regression analysis was used to measure the association between handgrip strength and anemia, while adjusting for other possible confounders. Subgroup analysis, stratified by sex and age, was performed.

Results

Among Korean adults aged ≥19 years, 745,296 (7.7%) had anemia. A higher odds ratio, adjusted for other covariates/factors (OR) of anemia occurred in the weak handgrip strength group than in the strong handgrip strength group (OR = 1.92, 95% CI: 1.58–2.33). The subgroup analysis showed a higher OR adjusted for other covariates/factors of anemia in the weak handgrip strength group than in the strong handgrip strength group, regardless of sex or age. However, the association was greater for males (OR = 2.13, 95% CI: 1.35–3.34) and for those aged ≥65 years (OR = 1.92, 95% CI: 1.42–2.58).

Conclusion

This study showed a strong association between handgrip strength and anemia that was particularly strong for males and those aged ≥65 years.

Citation: Gi Y-m, Jung B, Kim K-W, Cho J-H, Ha I-H (2020) Low handgrip strength is closely associated with anemia among adults: A cross-sectional study using Korea National Health and Nutrition Examination Survey (KNHANES). PLoS ONE 15(3): e0218058. https://doi.org/10.1371/journal.pone.0218058

Editor: Samson Gebremedhin, Addis Ababa University School of Public Health, ETHIOPIA

Received: May 22, 2019; Accepted: February 22, 2020; Published: March 20, 2020

Copyright: © 2020 Gi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: The KNHANES 6th and 7th were conducted by the Korea Center for Disease Control and Prevention (KCDC). All survey protocols were approved by the institutional review board (IRB) of the KCDC (approval numbers: 2013-07CON-03-4C, 2013-12EXP-03-5C, and 2015-01-02-6C). Informed consent was obtained from all participants when the surveys were conducted. Original data are publicly available for free in the KNHANES website (http://knhanes.cdc.go.kr) for purposes such as academic research.

Funding: This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

Competing interests: The authors have declared that no competing interests exist.

Introduction

Anemia occurs because of insufficient hemoglobin (Hb), which provides oxygen to the body. It is one of the major clinical problems affecting approximately 12% of the elderly, globally [1]. The World Health Organization (WHO) defines anemia as Hb values below 12 g/dl for females and 13 g/dl for males [2]. Anemia has an influence on mortality rate [3], disability [4], decline in physical activity level [4, 5], and decline in the quality of life [6], in the elderly. Furthermore, since anemia has a close relationship with many illnesses, it is recommended that when the Hb level is lower than the normal, it should always be followed-up clinically [5]. Hence, the prevalence of anemia can then be reduced by appropriate treatment or by preventing the underlying illnesses that are related to the aging process [7].

Muscle weakness is related to poor physical activity and incident mobility limitations in the elderly [3, 6, 8–11]. Handgrip strength, a simple, cost-effective tool used to measure strength, is utilized in the diagnosis of muscle weakness in epidemiological studies [10]. Handgrip strength can be used as a valuable tool for the screening of patients with anemia in the context of health services. [12]. Some research has reported that handgrip strength in middle-age (45–65 years) is related to functional limitations and disabilities at least 25 years later [3, 11, 13]. Therefore, handgrip strength has been considered a factor that predicts healthy aging [11]. Handgrip strength is also related to the strength of other muscle groups, and therefore can be a good index to represent overall strength [14]. Therefore, low handgrip strength signifies low muscle mass and poor clinical mobility [15].

Decline in muscle strength and muscle density is also associated with anemia [16], which results in the decline of mobility, self-care, and usual activities. Aging is associated with strength deficits that are related to frailty, loss of independence, and physical disability [17], and anemia is commonly related to aging. Oxidative stress is one of the most important mechanisms to explain the occurrence of age-related illnesses [18] including the decline in strength [19]. Because Hb concentration plays an important role in the oxidation of blood [20, 21], anemia, defined by Hb, represents a decline in the oxygenation function and can therefore be related to low strength [4].

Previous studies on the relationship between handgrip strength and anemia have been controversial. Alley et al. [22] found a direct relationship between reduction in Hb level and the reduction in handgrip strength in the elderly Australian [4]. Anemic patients had significantly lower handgrip strength than patients without anemia aged ≥65 years. In a study by Santos et al., which included 109 elderly participants, it was also concluded that grip could be used as a tool for screening for anemia in the elderly female population [12]. On the other hand, as Joosten et al. [23] reported that a study of the 109 elderly populatithat ons, also concluded that grip could be used as a tool for screening anemia in the elderly female population and anemia did not affect grip or gait speed in inpatient studies. In previous studies, the mechanism underlying this was unclear. Moreover, research on the association between handgrip strength and anemia in Korean adults has provided insufficient data for a clear conclusion. Therefore, in this study, we aimed to investigate the association between handgrip strength and anemia based on the data from the 6^th and 7^th Korean National Health and Nutrition Examination Survey (KNHANES).

Materials and methods

Study design and population

The present study used the data from the 6^th and 7^th KNHANES that was conducted from January 2013 to December 2017 [19]. KNHANES is a 3-yearly cross-sectional research, which includes examinations, health surveys, and nutritional surveys, and involves a representative sample of the entire Korean population, using a stratified cluster-sampling method.

The KNHANES 6^th and 7^th were conducted by the Korea Center for Disease Control and Prevention (KCDC). All survey protocols were approved by the institutional review board (IRB) of the KCDC (approval numbers: 2013-07CON-03-4C, 2013-12EXP-03-5C, and 2015-01-02-6C). Informed consent was obtained from all participants when the surveys were conducted. Original data are publicly and freely available at the KNHANES website (http://knhanes.cdc.go.kr) for purposes such as academic research. IRB approval was not required because the study did not deal with any sensitive information, but rather accessed only publicly available data from the KNHANES (JASENG IRB File No. 2019-03-009).

The KNHANES study sample consisted of Korean citizens (residents in group facilities, such as nursing homes, military, and prison as well as foreigners were excluded). To increase the representativeness of the sample and the accuracy of assumptions, sampling was designed to distinguish between province and city, neighborhood, towns, and townships, and the type of home, to extract data from sampled regions (investigated district). We included the 2013–2017 data in the handgrip strength data analysis. The exclusion criteria were as follows: those with missing data on anemia (n = 8,928) and on handgrip strength (n = 7,556), those aged under 19 years (n = 2,307), and other missing data (n = 3,797). Ultimately, the analyses were performed using data of 16,638 participants.(Fig 1).

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Fig 1. Participants flow diagram.

https://doi.org/10.1371/journal.pone.0218058.g001

Outcomes and other variables

Korea National Health and Nutrition Examination Survey (KNHANES) is conducted to evaluate the health and nutritional status of the Korean people. Twenty households were selected throughout 192 regions each year and 10,000 individuals aged 1 year and over were targeted for the KNHANES. Survey components were divided in 3 parts: Health Examination, Health Interview, and Nutrition Survey[24] (https://knhanes.cdc.go.kr/knhanes/eng/index.do).

Measurement of handgrip strength

Handgrip strength, to assess muscle strength, was obtained using a handgrip strength test in a health examination, according to the recommendations of the Institute of Medicine [14]. For the standard value of handgrip strength, we used the standard for the skeletal muscle mass (26 kg for men, 16 kg for women) suggested by the North American Foundation for the National Institutes of Health Sarcopenia Project published in 2015 [22]. The handgrip strength for each hand was measured three times using a digital grip strength dynamometer (TKK 5401; Takei Scientific Instruments Co, Ltd, Tokyo, Japan) [25]. Trained medical technicians instructed the study participants while in a sitting position to hold the dynamometer with the distal interphalangeal finger joints at a 90° angle to the handle, and to squeeze the handle as firmly as they could. Another handgrip strength measurement was done during expiration, after the participant had slowly stood up. Study participants conducted 3 attempts per hand, with a 1-minute rest period between each attempt to reduce the effect of fatigue due to repetition. The value for the handgrip strength measurements was the average of the three measurements, for either hand [26]. Using this mean handgrip strength values, participants were categorized into the weak (<26 kg for men, <16 kg for women) and strong (≥26 kg for men, ≥16 kg for women) groups.

Measurement of Hb levels

Blood analysis that included Hb level measurements was performed and used as an index to determine the level of anemia. The hemoglobin level was measured via the cyanide-free sodium lauryl sulphate method using XE-2100D (Sysmex, Kobe, Japan) [27]. In accordance with the WHO standard, male and female participants with Hb less than 13 g/dL and 12 g/dL, respectively, were defined as anemic patients [13].

Description of demographic and other characteristics of the study population

We analyzed the general characteristics, socioeconomic background characteristics, and lifestyle habits of the patients. The BMI, a value derived by dividing the weight with the square of height, was categorized into <18.5 kg/m² (underweight), 18.5–24.9 kg/m² (normal), and ≥25.0 kg/m² (overweight) [18]. For smoking, participants were categorized as nonsmokers, ex-smokers, or current smokers. The frequency of alcohol consumption was divided into four categories (‘none,’ ‘less than 1 time per month’, ‘1–4 times per month’, and ‘more than 5 times per month.’) For employment, participants were categorized into ‘unemployed (student, housewife, etc.)’ or ‘employed.’ For marital status, participants were categorized into three groups (‘married-cohabiting’ for those who had spouses or cohabiting partners; ‘married-non cohabiting, bereaved, or divorced’ for those who were living apart, bereaved, divorced; or ‘unmarried’ for those who were unmarried). Household income was categorized into four groups (low, low-moderate, moderate-high, and high). The criteria used in dividing them into four groups were based on the income quartile threshold for the sample household and sample population. This is the income level divided into four groups by gender and age according to the average monthly household equalization income [28, 29].

Educational level was also categorized into four groups (elementary school or less, middle school, high school, and college or higher). Level of daily workout referred to the frequency of strength exercise per week, and was categorized into four groups (‘none’; ‘light’ [1 day]; ‘moderate’ [2~3 days]; and ‘heavy/extreme’ [4 days or more]).

Measurement and classification of other variables of interest

The nutritional information used in our research was obtained from the food intake nutrition surveys collected by dieticians who visited the homes of participants. The survey method was a face-to-face interview within the home. The survey inquired about topics such as dietary behavior, dietary supplement use, food security, food frequency, food and dietary intake. The food frequency questionnaire is composed of 63 food items that represent key sources of energy and nutrients. The questionnaire is designed as an open-ended survey for reporting various dishes and foods; the 24-h recall method was used with various measuring aids. We obtained data on vitamin A and C intake based on the reported information collected using the food intake questionnaire [24]. For nutritional characteristics, iron intake, vitamin A intake, and vitamin C intake per day were categorized as ‘insufficient’ if the intake was lower than the recommended level by sex and age and ‘sufficient’ if the intake was above the recommended level. All blood samples were drawn after fasting and were analyzed within 24 hours of being drawn. The 2015 standards of the Dietary Reference Intakes for Koreans (KDRIs) were used for iron and vitamin C intake per day. For vitamin A intake, the 2010 KDRIs standards [30] were used with identical units (μg RE/day) for KHANES and KDRIs [31] (μg RAE/day), in 2015. Vitamin A intake per day for males and females aged 19–49 and ≥50 years were 750 and 700 μg RE/day; and 650 and 600 μg RE/day, respectively. Vitamin C intake per day was 100 mg for both males and females over 19 years old. Iron intake per day for males was 10 and 9 mg/day for those aged 19–64 and ≥65 years, respectively; while for females aged 19–49, 50–74, and ≥75 years, was 14, 8, and 7 mg/day, respectively.

Hypertension, cancer, hyperlipidemia, cardiovascular disease, kidney disease, bone disease, and thyroid disease were the comorbid diseases included. Participants were categorized into a ‘yes’ or ‘no’ group based on the diagnosis of at least one of these diseases.

Statistical analysis

Because KNHANES data were obtained using a complex sampling design, all statistical analysis methods used complex sample analyses considering weight, stratified variables, and cluster sampling. We selected factors associated with anemia for the statistical adjustment, from previous studies. Differences in sociodemographic factors (gender [32, 33], age [34], region [35], marital status [36], income [37], employment [38], and education [39]), lifestyle factors (alcohol consumption and smoking [40], and physical activity [4, 41]), and illness and health-related factors (BMI [42], vitamin intake [43], iron intake [44–47], comorbid illnesses [48–52], and handgrip strength [12]); due to the presence of anemia, were analyzed using a complex sample analysis by Chi square (χ²) test. Categorical variables were presented as proportions (n, %) using the χ² test of independence, while continuous variables were presented with the estimated value ± standard error (SE).

A Chi-square test was performed on risk factors associated with anemia. Furthermore, to identify factors associated with anemia, the odds ratio (OR) and 95% confidence intervals (95% CI) were obtained through a binary logistic regression analysis after setting anemia as the dependent variable and handgrip strength as the main independent variable, while controlling for sociodemographic factors, lifestyle factors, and illness and health-related factors.

The equations of the logistic regressions are as below: where p_i is the probability that each individual i develops dementia. The association between handgrip strength and anemia was subgroup-analyzed by gender (male/female) and age (younger or older than 65 years). All statistical analyses were performed using SPSS version 25.0 (SPSS Inc., Chicago, IL, USA) and SAS version 9.4 (SAS Institute Inc, Cary, NC), and the significance level of all tests was defined as a p-value less than 0.05.

Results

Table 1 shows the general characteristics of the participants. Overall, 7.7% of patients had anemia. About half (51.2%) of the participants were female, of these, 11.9% had anemia. Overall, 6.7% and 15.8% of participants were in the strong and weak handgrip strength groups, respectively (p<0.001). The mean age of participants with anemia was higher (50.27 years) than that of those in the group without anemia (46.14 years) (p<0.001). According to the individual lifestyle habits and the level of daily workout, those in the light (1 day) daily workout group (615,680 participants, 8.5%) had anemia, and had a higher prevalence of anemia than those in the moderate (5.7%) and heavy/extreme (4.9%) daily workout groups (p<0.001). For the nutritional and disease-related factors, the prevalence rate of anemia in the group with comorbid diseases was 2.5% higher than in the group without comorbid diseases (p<0.001). For iron intake, the prevalence rate of anemia was 3.5% greater in the insufficient group than in the sufficient group (p<0.001).

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Table 1. Description of the basic characteristics of the study participants.

https://doi.org/10.1371/journal.pone.0218058.t001

Table 2 shows the description of the anemia status of the study participants and stratification based on gender and age. Anemia prevalence rate was higher in females (11.9%) and in participants ≥65 years (12.7%) (p<0.001, Table 2).

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Table 2. Description of anemia status among the study participants.

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Table 3 shows the description of handgrip strength in the entire participants, and stratification based on age, sex, and anemia status. Handgrip prevalence rate was higher in females (87.8%), in participants <65 years (94.4%) and in participants without anemia (88.7%) (p<0.001, Table 3).

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Table 3. Description of handgrip strength in the entire participant group.

https://doi.org/10.1371/journal.pone.0218058.t003

Table 4 shows the association between handgrip strength and anemia using logistic regression analyses. The OR (odds ratio) for weak handgrip strength compared to strong handgrip strength was 2.02, 1.98, and 1.92 in Models 1, 2, and 3, respectively, showing a significant association between weak handgrip strength and anemia (p<0.001). The OR of underweight and overweight BMI was higher than of the normal weight, and the OR was also higher in persons with other diseases. Moreover, the prevalence of anemia was higher in persons with insufficient iron, vitamin A, and vitamin C intake per day than in persons with sufficient intake (Table 4).

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Table 4. Association between handgrip and anemia.

https://doi.org/10.1371/journal.pone.0218058.t004

Table 5 demonstrates the association between handgrip strength and anemia stratified by sex and age. Regardless of sex and age, there was a significant association between handgrip strength and anemia. In particular, the trend of weak handgrip strength in those with anemia compared to those without anemia was more pronounced in males than in females (OR: 2.13 p = 0.001, 95% CI: 1.35–3.34); and in those aged ≥65 years compared to those <65 (OR: 1.92 p<0.001, 95% CI: 1.42–2.58) (Table 5).

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Table 5. Association between handgrip and anemia by sub-group.

https://doi.org/10.1371/journal.pone.0218058.t005

Discussion

This study analyzed the association between handgrip strength and anemia using representative, reliable data for all Korean citizens. We found that handgrip strength and anemia had a clear correlation. The proportion of those with anemia and weaker handgrip strength was higher than that found for the other groups. Even after controlling for sociodemographic factors, there was a clear correlation between handgrip strength and anemia. Furthermore, after controlling for individual lifestyle habits, such as smoking, alcohol consumption, nutritional and disease-related factors, handgrip strength and anemia showed a very significant association. In comparing the group with and without anemia, indices such as BMI, level of daily workout, and iron intake per day showed significant differences. One noticeable finding was that the prevalence rate of anemia was higher for non-smokers and those with a lower consumption of alcohol (Table 1). This may be due to the fact that females formed a greater proportion of those with anemia.

The relationship between anemia and handgrip strength can be explained by a biological mechanism as reported in previous studies. The low strength can be explained by weakness and fatigue which can increase the risk of disability in these individuals [53]. Hemoglobin, in the red blood cells, is responsible for transporting oxygen to various parts of the body. Therefore, the lower blood concentration of Hb means lower oxygen is transported, and this can increase the risk of various mobility disorders along with fatigue [54]. Because the hemoglobin concentration plays an important role in the oxygenation of the blood [20, 21], anemia, defined by levels of Hb, represents a reduction in oxygenation function. Hypoxia due to anemia can reduce the oxygen supply to the muscles and thereby affect the strength of the muscles [4].

We performed subgroup analyses by sex and age; these were predicted to affect anemia. In the subgroup by sex, the correlation between handgrip strength and anemia was higher for males compared to females. For males, indices such as BMI, level of daily workout, and comorbid diseases had significant relationships with anemia (Table 2). Additionally, in the subgroups by age, the association between handgrip strength and anemia was more pronounced in participants ≥65 years compared to those <65 years Although the proportion of females with anemia was far higher in the group <65 years, the male/female distinction did not show large differences in those ≥65 years. It was also found that BMI, level of daily workout, and iron intake per day were significantly related to anemia in both groups (Table 3).

Previous studies have shown significant relationships between anemia and handgrip strength in only females, rather than males. These included a study that found significant differences in Hb levels in males among the South African population >40 years old [55] and a study that found an association between anemia and handgrip strength in the Brazilian female population >60 years old [12]. However, this study showed a higher OR of anemia in the weak handgrip strength group compared to the strong handgrip strength group in both males and females, and this association was greater in males compared to females. The differences may be due to heterogeneity of the aging population with regards to race, living environments, and health problems, all factors that can affect Hb levels [56].

Furthermore, previous studies on the elderly have found a clear association between handgrip strength and anemia. According to the research by Hirani V et al., the decline in Hb concentration in Australian elderly participants was directly related to the decline in handgrip strength [57]). Pennix et al also reported that patients with anemia (defined by the Hb level among elderly participants >65 years), had far lower handgrip strength compared to patients without anemia [4]. Moreover, research on the association between anemia and handgrip strength in the elderly population >90 years old [55, 58] and research showing an association between anemia, handgrip strength, and lower-body strength in the elderly >100 years old [59] demonstrated that the association may increase as age increases. The reason could be that the reduction in handgrip strength due to aging can represent the overall health of the elderly [60]. In particular, because the elderly often have higher blood concentration of C-reactive protein, acute or chronic inflammation can result in an even larger physical decline [4, 5]. Therefore, the maintenance and management of handgrip strength are important especially in the elderly population, and it will be important to identify factors that affect handgrip strength [61].

There are some limitations to keep in mind while interpreting these results. First, because this study used a cross-sectional study design based on the KNHANES, caution must be taken in interpreting a causal relationship between the variables. In other words, we cannot assume that handgrip strength is an independent causative factor of anemia or an epiphenomenon. Second, many variables measured at a single time point were used to assess the effects of handgrip and anemia. This may negatively affect the accuracy of the data to some extent. The socio-demographic characteristics of the study population were collected through surveys. Therefore, this may have caused a recall bias. Third, there is a limitation in identifying the risk factors for anemia because of insufficient nutritional data. Micronutrient deficiencies including folate and vitamin B12 are main causes of anemia [62]; however, the study lacks data on nutritional status. Therefore, it was difficult to clearly consider the effect of diseases that could be related to anemia. Fourth, because KNHANES only considered Hb levels to define anemia, it was difficult to consider the types or causes of anemia. Therefore, additional research is necessary on variables that can affect anemia; it is anticipated that the results of such a study would have clinical applicability. Finally, we did not process missing data using methods such as multiple imputations (MI) and could not adjust for more stringent semantic thresholds, which could only be solved by well-designed randomized controlled trials. However, I believe that the results obtained with missing data excluded were no different from the results obtained if the missing data had been processed using MI. This is because of the nationally representative sample included in this study. The strict important thresholds can be addressed later using well-designed clinical studies.

Despite these limitations, this research has the following advantages. First, this study is the first to examine the correlation between handgrip strength and anemia in Korean adults. Previous studies on the relationship between handgrip strength and anemia have been controversial [4, 12, 22, 23]. Previous studies have shown significant relationships between anemia and handgrip strength in only females [12, 55] or the elderly [55, 57–59]. In our study, we found that regardless of sex and age, there was a significant association between handgrip strength and anemia. Second, the study was based on reliable data obtained from a nationwide survey targeting a sample representative of the general Korean population [24]. Therefore, the results of this study showed that the relationship between handgrip strength and anemia was very reliable. Third, various covariates such as sociodemographic factors, lifestyle factors and illness related factors that could affect the association between anemia and handgrip strength adjusted in model. Finally, this study divided subgroups according to gender and age, and compared the characteristics of the anemia population. Through this, it was possible to determine the high prevalence of anemia in each subgroup.

Through this study, we found that regardless of sex and age, there was a significant association between handgrip strength and anemia. Therefore, handgrip strength can be used as a risk factor when screening for anemia in patients, and can be used in clinical practice for testing for anemia in the elderly, in epidemiological studies, or during treatments[12]. In particular, handgrip strength may be a useful screening tool for the elderly who are more likely to develop other diseases associated with anemia and for males who have lower prevalence of anemia than females. Further study is needed to identify and clinically track populations more likely to develop anemia by measuring handgrip strength.

Conclusion

In conclusion, there was a strong association between handgrip strength and anemia. In particular, the association between handgrip strength and anemia was more likely to occur in males and those who were older than 65 years.

References

1. Salive ME, Cornoni-Huntley J, Guralnik JM, Phillips CL, Wallace RB, Ostfeld AM, et al. Anemia and hemoglobin levels in older persons: relationship with age, gender, and health status. Journal of the American Geriatrics Society. 1992;40(5):489–96. pmid:1634703
- View Article
- PubMed/NCBI
- Google Scholar
2. Organization WH. Nutritional anemia: report of a WHO Scientific Group. Geneva: World Health Organization. 1968.
3. Ferrucci L, Guralnik JM, Buchner D, Kasper J, Lamb SE, Simonsick EM, et al. Departures from linearity in the relationship between measures of muscular strength and physical performance of the lower extremities: the Women’s Health and Aging Study. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences. 1997;52(5):M275–M85.
- View Article
- Google Scholar
4. Penninx BW, Pahor M, Cesari M, Corsi AM, Woodman RC, Bandinelli S, et al. Anemia is associated with disability and decreased physical performance and muscle strength in the elderly. Journal of the American Geriatrics Society. 2004;52(5):719–24. pmid:15086651
- View Article
- PubMed/NCBI
- Google Scholar
5. Penninx BW, Guralnik JM, Onder G, Ferrucci L, Wallace RB, Pahor M. Anemia and decline in physical performance among older persons. The American journal of medicine. 2003;115(2):104–10. pmid:12893395
- View Article
- PubMed/NCBI
- Google Scholar
6. Sallinen J, Stenholm S, Rantanen T, Heliövaara M, Sainio P, Koskinen S. Hand‐grip strength cut points to screen older persons at risk for mobility limitation. Journal of the American Geriatrics Society. 2010;58(9):1721–6. pmid:20863331
- View Article
- PubMed/NCBI
- Google Scholar
7. Gualandro SF, Hojaij N, Jacob Filho W. Deficiência de ferro no idoso. Rev Bras Hematol Hemoter. 2010;32(supl 2):57–61.
- View Article
- Google Scholar
8. Manini TM, Clark BC. Dynapenia and aging: an update. Journals of Gerontology Series A: Biomedical Sciences and Medical Sciences. 2011;67(1):28–40.
- View Article
- Google Scholar
9. Manini TM, Visser M, Won-Park S, Patel KV, Strotmeyer ES, Chen H, et al. Knee extension strength cutpoints for maintaining mobility. Journal of the American Geriatrics Society. 2007;55(3):451–7. pmid:17341251
- View Article
- PubMed/NCBI
- Google Scholar
10. Hicks GE, Shardell M, Alley DE, Miller RR, Bandinelli S, Guralnik J, et al. Absolute strength and loss of strength as predictors of mobility decline in older adults: the InCHIANTI study. Journals of Gerontology: Series A: Biomedical Sciences and Medical Sciences. 2011;67(1):66–73.
- View Article
- Google Scholar
11. Lauretani F, Russo CR, Bandinelli S, Bartali B, Cavazzini C, Di Iorio A, et al. Age-associated changes in skeletal muscles and their effect on mobility: an operational diagnosis of sarcopenia. Journal of applied physiology. 2003;95(5):1851–60. pmid:14555665
- View Article
- PubMed/NCBI
- Google Scholar
12. Santos PHS, Carmo ÉA, Carneiro JAO, Nery AA, Casotti CA. Handgrip strength: An effective screening instrument for anemia in the elderly women. Public Health Nursing. 2019;36(2):178–83. pmid:30628133
- View Article
- PubMed/NCBI
- Google Scholar
13. Chung H, Moon H, Song B, Kim M. Hemoglobin, hematocrit and serum ferritin as markers of iron status. Korean J Nutr. 1991;24(5):450–7.
- View Article
- Google Scholar
14. Pate RR, Daniels S. Institute of Medicine report on fitness measures and health outcomes in youth. JAMA pediatrics. 2013;167(3):221–2. pmid:23358923
- View Article
- PubMed/NCBI
- Google Scholar
15. Yoo J-I, Ha Y-C, Kwon H-B, Lee Y-K, Koo K-H, Yoo M-J. High prevalence of sarcopenia in Korean patients after hip fracture: a case-control study. Journal of Korean medical science. 2016;31(9):1479–84. pmid:27510394
- View Article
- PubMed/NCBI
- Google Scholar
16. Vulser H, Wiernik E, Hoertel N, Thomas F, Pannier B, Czernichow S, et al. Association between depression and anemia in otherwise healthy adults. Acta Psychiatrica Scandinavica. 2016;134(2):150–60. pmid:27238642
- View Article
- PubMed/NCBI
- Google Scholar
17. Liguori I, Russo G, Curcio F, Bulli G, Aran L, Della-Morte D, et al. Oxidative stress, aging, and diseases. Clinical interventions in aging. 2018;13:757. pmid:29731617
- View Article
- PubMed/NCBI
- Google Scholar
18. Razak F, Anand SS, Shannon H, Vuksan V, Davis B, Jacobs R, et al. Defining obesity cut points in a multiethnic population. Circulation. 2007;115(16):2111. pmid:17420343
- View Article
- PubMed/NCBI
- Google Scholar
19. Ahn S. Korean national health and nutrition examination survey: MS Thesis; 2005.
20. Giulivi C, Davies K. A novel antioxidant role for hemoglobin. The comproportionation of ferrylhemoglobin with oxyhemoglobin. Journal of Biological Chemistry. 1990;265(32):19453–60. pmid:2174037
- View Article
- PubMed/NCBI
- Google Scholar
21. Grune T. Oxidative stress, aging and the proteasomal system. Biogerontology. 2000;1(1):31–40. pmid:11707918
- View Article
- PubMed/NCBI
- Google Scholar
22. Alley DE, Shardell MD, Peters KW, McLean RR, Dam T-TL, Kenny AM, et al. Grip strength cutpoints for the identification of clinically relevant weakness. Journals of Gerontology Series A: Biomedical Sciences and Medical Sciences. 2014;69(5):559–66.
- View Article
- Google Scholar
23. Joosten E, Detroyer E, Milisen K. Effect of anaemia on hand grip strength, walking speed, functionality and 1 year mortality in older hospitalized patients. BMC geriatrics. 2016;16(1):153. pmid:27543049
- View Article
- PubMed/NCBI
- Google Scholar
24. Kweon S, Kim Y, Jang M-j, Kim Y, Kim K, Choi S, et al. Data resource profile: the Korea national health and nutrition examination survey (KNHANES). International journal of epidemiology. 2014;43(1):69–77. pmid:24585853
- View Article
- PubMed/NCBI
- Google Scholar
25. Yoo J-I, Choi H, Ha Y-C. Mean hand grip strength and cut-off value for sarcopenia in Korean adults using KNHANES VI. Journal of Korean medical science. 2017;32(5):868–72. pmid:28378563
- View Article
- PubMed/NCBI
- Google Scholar
26. Roberts HC, Denison HJ, Martin HJ, Patel HP, Syddall H, Cooper C, et al. A review of the measurement of grip strength in clinical and epidemiological studies: towards a standardised approach. Age and ageing. 2011;40(4):423–9. pmid:21624928
- View Article
- PubMed/NCBI
- Google Scholar
27. Park JY, Lee SW. A history of repetitive cesarean section is a risk factor of anemia in healthy perimenopausal women: The Korea National Health and Nutrition Examination Survey 2010–2012. PloS one. 2017;12(11).
- View Article
- Google Scholar
28. Kim Y. The Korea National Health and nutrition examination survey (KNHANES): current status and challenges. Epidemiology and health. 2014;36.
- View Article
- Google Scholar
29. Park YN. Regional Disparities of Health Status in Korea: Finding from KNHANES (2007–2014). 2017.
30. Society MoHaWTKN. Dietary Reference Intakes for Koreans 2010. 2010.
31. Society MoHaWTKN. Dietary Reference Intakes for Koreans 2015. Seoul: The Korean Nutrition Society. 2015.
32. Chaves PH, Semba RD, Leng SX, Woodman RC, Ferrucci L, Guralnik JM, et al. Impact of anemia and cardiovascular disease on frailty status of community-dwelling older women: the Women’s Health and Aging Studies I and II. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences. 2005;60(6):729–35.
- View Article
- Google Scholar
33. RESILIENCE B. The State Of Food Security And Nutrition In The World. Rome: Building resilience for peace and food security. 2017.
34. Gaskell H, Derry S, Moore RA, McQuay HJ. Prevalence of anaemia in older persons: systematic review. BMC geriatrics. 2008;8(1):1.
- View Article
- Google Scholar
35. Adamu AL, Crampin A, Kayuni N, Amberbir A, Koole O, Phiri A, et al. Prevalence and risk factors for anemia severity and type in Malawian men and women: urban and rural differences. Population health metrics. 2017;15(1):12. pmid:28356159
- View Article
- PubMed/NCBI
- Google Scholar
36. Mugisha JO, Baisley K, Asiki G, Seeley J, Kuper H. Prevalence, types, risk factors and clinical correlates of anaemia in older people in a rural Ugandan population. PLoS One. 2013;8(10).
- View Article
- Google Scholar
37. Balarajan Y, Ramakrishnan U, Özaltin E, Shankar AH, Subramanian S. Anaemia in low-income and middle-income countries. The lancet. 2011;378(9809):2123–35.
- View Article
- Google Scholar
38. Rammohan A, Awofeso N, Robitaille M-C. Addressing female iron-deficiency anaemia in india: is vegetarianism the major obstacle? ISRN Public Health. 2011;2012.
- View Article
- Google Scholar
39. Kim Y-J, Do Han K, Cho K-H, Kim Y-H, Park Y-G. Anemia and health-related quality of life in South Korea: data from the Korean national health and nutrition examination survey 2008–2016. BMC public health. 2019;19(1):735. pmid:31196013
- View Article
- PubMed/NCBI
- Google Scholar
40. Masukume G, Khashan AS, Kenny LC, Baker PN, Nelson G, Consortium S. Risk factors and birth outcomes of anaemia in early pregnancy in a nulliparous cohort. PloS one. 2015;10(4):e0122729. pmid:25875012
- View Article
- PubMed/NCBI
- Google Scholar
41. Chaves PH, Ashar B, Guralnik JM, Fried LP. Looking at the relationship between hemoglobin concentration and prevalent mobility difficulty in older women. Should the criteria currently used to define anemia in older people be reevaluated? Journal of the American Geriatrics Society. 2002;50(7):1257–64. pmid:12133021
- View Article
- PubMed/NCBI
- Google Scholar
42. Zakai NA, French B, Arnold AM, Newman AB, Fried LF, Robbins J, et al. Hemoglobin decline, function, and mortality in the elderly: the cardiovascular health study. American journal of hematology. 2013;88(1):5–9. pmid:23044913
- View Article
- PubMed/NCBI
- Google Scholar
43. Al-Mekhlafi HM, Al-Zabedi EM, Al-Maktari MT, Atroosh WM, Al-Delaimy AK, Moktar N, et al. Effects of vitamin A supplementation on iron status indices and iron deficiency anaemia: a randomized controlled trial. Nutrients. 2014;6(1):190–206.
- View Article
- Google Scholar
44. Gordon SR, Smith RE, Power GC. The role of endoscopy in the evaluation of iron deficiency anemia in patients over the age of 50. American Journal of Gastroenterology. 1994;89(11).
- View Article
- Google Scholar
45. Organization WH. Iron deficiency anemia. assessment, prevention, and control. A guide for programme managers. 2001:47–62.
46. Jacobs A, Greenman D, Owen E, Cavill I. Ascorbic acid status in iron-deficiency anaemia. Journal of clinical pathology. 1971;24(8):694–7. pmid:5130535
- View Article
- PubMed/NCBI
- Google Scholar
47. Cook JD, Monsen ER. Food iron absorption in human subjects. III. Comparison of the effect of animal proteins on nonheme iron absorption. The American journal of clinical nutrition. 1976;29(8):859–67. pmid:941868
- View Article
- PubMed/NCBI
- Google Scholar
48. Hong CH, Falvey C, Harris TB, Simonsick EM, Satterfield S, Ferrucci L, et al. Anemia and risk of dementia in older adults: findings from the Health ABC study. Neurology. 2013;81(6):528–33. pmid:23902706
- View Article
- PubMed/NCBI
- Google Scholar
49. Shavelle RM, MacKenzie R, Paculdo DR. Anemia and mortality in older persons: does the type of anemia affect survival? International journal of hematology. 2012;95(3):248–56. pmid:22351246
- View Article
- PubMed/NCBI
- Google Scholar
50. Zakai NA, Katz R, Hirsch C, Shlipak MG, Chaves PH, Newman AB, et al. A prospective study of anemia status, hemoglobin concentration, and mortality in an elderly cohort: the Cardiovascular Health Study. Archives of internal medicine. 2005;165(19):2214–20. pmid:16246985
- View Article
- PubMed/NCBI
- Google Scholar
51. Lucca U, Tettamanti M, Mosconi P, Apolone G, Gandini F, Nobili A, et al. Association of mild anemia with cognitive, functional, mood and quality of life outcomes in the elderly: the “Health and Anemia” study. PloS one. 2008;3(4).
- View Article
- Google Scholar
52. den Elzen WP, Willems JM, Westendorp RG, de Craen AJ, Assendelft WJ, Gussekloo J. Effect of anemia and comorbidity on functional status and mortality in old age: results from the Leiden 85-plus Study. Cmaj. 2009;181(3–4):151–7. pmid:19635749
- View Article
- PubMed/NCBI
- Google Scholar
53. Fukushima T, Nakano J, Ishii S, Natsuzako A, Kawachi H, Sakamoto J, et al. Influence of Hemoglobin Level on Muscle and Physical Functions, Activities of Daily Living, and Quality of Life in Patients With Hematological Malignancies. Integrative Cancer Therapies. 2019;18:1534735419842196. pmid:30947558
- View Article
- PubMed/NCBI
- Google Scholar
54. Cho S-B. Effect of Muscular Reinforcement Exercise of Serum Albumin, WBC and Hemoglobin in the Elderly Women The journals of the Korean Society Of Sports Science. 2013;22(4):1075–81.
- View Article
- Google Scholar
55. Payne CF, Davies JI, Gomez-Olive FX, Hands KJ, Kahn K, Kobayashi LC, et al. Cross-sectional relationship between haemoglobin concentration and measures of physical and cognitive function in an older rural South African population. J Epidemiol Community Health. 2018;72(9):796–802. pmid:29680801
- View Article
- PubMed/NCBI
- Google Scholar
56. Eisenstaedt R, Penninx BW, Woodman RC. Anemia in the elderly: current understanding and emerging concepts. Blood reviews. 2006;20(4):213–26. pmid:16472893
- View Article
- PubMed/NCBI
- Google Scholar
57. Hirani V, Naganathan V, Blyth F, Le Couteur DG, Seibel MJ, Waite LM, et al. Low hemoglobin concentrations are associated with sarcopenia, physical performance, and disability in older Australian men in cross-sectional and longitudinal analysis: the Concord Health and Ageing in Men project. Journals of Gerontology Series A: Biomedical Sciences and Medical Sciences. 2016;71(12):1667–75.
- View Article
- Google Scholar
58. Thein M, Ershler WB, Artz AS, Tecson J, Robinson BE, Rothstein G, et al. Diminished quality of life and physical function in community-dwelling elderly with anemia. Medicine. 2009;88(2):107. pmid:19282701
- View Article
- PubMed/NCBI
- Google Scholar
59. Haslam A, Hausman DB, Davey A, Cress ME, Johnson MA, Poon LW. Associations of anemia and physical function in Georgia centenarians. Journal of the American Geriatrics Society. 2012;60(12):2362. pmid:23231554
- View Article
- PubMed/NCBI
- Google Scholar
60. Rijk JM, Roos PR, Deckx L, van den Akker M, Buntinx F. Prognostic value of handgrip strength in people aged 60 years and older: A systematic review and meta-analysis. Geriatrics & gerontology international. 2016;16(1):5–20.
- View Article
- Google Scholar
61. Lee J, Hong YS, Park S-H, Kang KY. High serum uric acid level is associated with greater handgrip strength in the aged population. Arthritis research & therapy. 2019;21(1):73.
- View Article
- Google Scholar
62. Antwi-Bafour S, Hammond S, Adjei JK, Kyeremeh R, Martin-Odoom A, Ekem I. A case–control study of prevalence of anemia among patients with type 2 diabetes. Journal of medical case reports. 2016;10(1):110. pmid:27142617
- View Article
- PubMed/NCBI
- Google Scholar

[ref1] 1. Salive ME, Cornoni-Huntley J, Guralnik JM, Phillips CL, Wallace RB, Ostfeld AM, et al. Anemia and hemoglobin levels in older persons: relationship with age, gender, and health status. Journal of the American Geriatrics Society. 1992;40(5):489–96. pmid:1634703
View Article
PubMed/NCBI
Google Scholar

[2] View Article

[3] PubMed/NCBI

[4] Google Scholar

[ref2] 2. Organization WH. Nutritional anemia: report of a WHO Scientific Group. Geneva: World Health Organization. 1968.

[ref3] 3. Ferrucci L, Guralnik JM, Buchner D, Kasper J, Lamb SE, Simonsick EM, et al. Departures from linearity in the relationship between measures of muscular strength and physical performance of the lower extremities: the Women’s Health and Aging Study. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences. 1997;52(5):M275–M85.
View Article
Google Scholar

[7] View Article

[8] Google Scholar

[ref4] 4. Penninx BW, Pahor M, Cesari M, Corsi AM, Woodman RC, Bandinelli S, et al. Anemia is associated with disability and decreased physical performance and muscle strength in the elderly. Journal of the American Geriatrics Society. 2004;52(5):719–24. pmid:15086651
View Article
PubMed/NCBI
Google Scholar

[10] View Article

[11] PubMed/NCBI

[12] Google Scholar

[ref5] 5. Penninx BW, Guralnik JM, Onder G, Ferrucci L, Wallace RB, Pahor M. Anemia and decline in physical performance among older persons. The American journal of medicine. 2003;115(2):104–10. pmid:12893395
View Article
PubMed/NCBI
Google Scholar

[14] View Article

[15] PubMed/NCBI

[16] Google Scholar

[ref6] 6. Sallinen J, Stenholm S, Rantanen T, Heliövaara M, Sainio P, Koskinen S. Hand‐grip strength cut points to screen older persons at risk for mobility limitation. Journal of the American Geriatrics Society. 2010;58(9):1721–6. pmid:20863331
View Article
PubMed/NCBI
Google Scholar

[18] View Article

[19] PubMed/NCBI

[20] Google Scholar

[ref7] 7. Gualandro SF, Hojaij N, Jacob Filho W. Deficiência de ferro no idoso. Rev Bras Hematol Hemoter. 2010;32(supl 2):57–61.
View Article
Google Scholar

[22] View Article

[23] Google Scholar

[ref8] 8. Manini TM, Clark BC. Dynapenia and aging: an update. Journals of Gerontology Series A: Biomedical Sciences and Medical Sciences. 2011;67(1):28–40.
View Article
Google Scholar

[25] View Article

[26] Google Scholar

[ref9] 9. Manini TM, Visser M, Won-Park S, Patel KV, Strotmeyer ES, Chen H, et al. Knee extension strength cutpoints for maintaining mobility. Journal of the American Geriatrics Society. 2007;55(3):451–7. pmid:17341251
View Article
PubMed/NCBI
Google Scholar

[28] View Article

[29] PubMed/NCBI

[30] Google Scholar

[ref10] 10. Hicks GE, Shardell M, Alley DE, Miller RR, Bandinelli S, Guralnik J, et al. Absolute strength and loss of strength as predictors of mobility decline in older adults: the InCHIANTI study. Journals of Gerontology: Series A: Biomedical Sciences and Medical Sciences. 2011;67(1):66–73.
View Article
Google Scholar

[32] View Article

[33] Google Scholar

[ref11] 11. Lauretani F, Russo CR, Bandinelli S, Bartali B, Cavazzini C, Di Iorio A, et al. Age-associated changes in skeletal muscles and their effect on mobility: an operational diagnosis of sarcopenia. Journal of applied physiology. 2003;95(5):1851–60. pmid:14555665
View Article
PubMed/NCBI
Google Scholar

[35] View Article

[36] PubMed/NCBI

[37] Google Scholar

[ref12] 12. Santos PHS, Carmo ÉA, Carneiro JAO, Nery AA, Casotti CA. Handgrip strength: An effective screening instrument for anemia in the elderly women. Public Health Nursing. 2019;36(2):178–83. pmid:30628133
View Article
PubMed/NCBI
Google Scholar

[39] View Article

[40] PubMed/NCBI

[41] Google Scholar

[ref13] 13. Chung H, Moon H, Song B, Kim M. Hemoglobin, hematocrit and serum ferritin as markers of iron status. Korean J Nutr. 1991;24(5):450–7.
View Article
Google Scholar

[43] View Article

[44] Google Scholar

[ref14] 14. Pate RR, Daniels S. Institute of Medicine report on fitness measures and health outcomes in youth. JAMA pediatrics. 2013;167(3):221–2. pmid:23358923
View Article
PubMed/NCBI
Google Scholar

[46] View Article

[47] PubMed/NCBI

[48] Google Scholar

[ref15] 15. Yoo J-I, Ha Y-C, Kwon H-B, Lee Y-K, Koo K-H, Yoo M-J. High prevalence of sarcopenia in Korean patients after hip fracture: a case-control study. Journal of Korean medical science. 2016;31(9):1479–84. pmid:27510394
View Article
PubMed/NCBI
Google Scholar

[50] View Article

[51] PubMed/NCBI

[52] Google Scholar

[ref16] 16. Vulser H, Wiernik E, Hoertel N, Thomas F, Pannier B, Czernichow S, et al. Association between depression and anemia in otherwise healthy adults. Acta Psychiatrica Scandinavica. 2016;134(2):150–60. pmid:27238642
View Article
PubMed/NCBI
Google Scholar

[54] View Article

[55] PubMed/NCBI

[56] Google Scholar

[ref17] 17. Liguori I, Russo G, Curcio F, Bulli G, Aran L, Della-Morte D, et al. Oxidative stress, aging, and diseases. Clinical interventions in aging. 2018;13:757. pmid:29731617
View Article
PubMed/NCBI
Google Scholar

[58] View Article

[59] PubMed/NCBI

[60] Google Scholar

[ref18] 18. Razak F, Anand SS, Shannon H, Vuksan V, Davis B, Jacobs R, et al. Defining obesity cut points in a multiethnic population. Circulation. 2007;115(16):2111. pmid:17420343
View Article
PubMed/NCBI
Google Scholar

[62] View Article

[63] PubMed/NCBI

[64] Google Scholar

[ref19] 19. Ahn S. Korean national health and nutrition examination survey: MS Thesis; 2005.

[ref20] 20. Giulivi C, Davies K. A novel antioxidant role for hemoglobin. The comproportionation of ferrylhemoglobin with oxyhemoglobin. Journal of Biological Chemistry. 1990;265(32):19453–60. pmid:2174037
View Article
PubMed/NCBI
Google Scholar

[67] View Article

[68] PubMed/NCBI

[69] Google Scholar

[ref21] 21. Grune T. Oxidative stress, aging and the proteasomal system. Biogerontology. 2000;1(1):31–40. pmid:11707918
View Article
PubMed/NCBI
Google Scholar

[71] View Article

[72] PubMed/NCBI

[73] Google Scholar

[ref22] 22. Alley DE, Shardell MD, Peters KW, McLean RR, Dam T-TL, Kenny AM, et al. Grip strength cutpoints for the identification of clinically relevant weakness. Journals of Gerontology Series A: Biomedical Sciences and Medical Sciences. 2014;69(5):559–66.
View Article
Google Scholar

[75] View Article

[76] Google Scholar

[ref23] 23. Joosten E, Detroyer E, Milisen K. Effect of anaemia on hand grip strength, walking speed, functionality and 1 year mortality in older hospitalized patients. BMC geriatrics. 2016;16(1):153. pmid:27543049
View Article
PubMed/NCBI
Google Scholar

[78] View Article

[79] PubMed/NCBI

[80] Google Scholar

[ref24] 24. Kweon S, Kim Y, Jang M-j, Kim Y, Kim K, Choi S, et al. Data resource profile: the Korea national health and nutrition examination survey (KNHANES). International journal of epidemiology. 2014;43(1):69–77. pmid:24585853
View Article
PubMed/NCBI
Google Scholar

[82] View Article

[83] PubMed/NCBI

[84] Google Scholar

[ref25] 25. Yoo J-I, Choi H, Ha Y-C. Mean hand grip strength and cut-off value for sarcopenia in Korean adults using KNHANES VI. Journal of Korean medical science. 2017;32(5):868–72. pmid:28378563
View Article
PubMed/NCBI
Google Scholar

[86] View Article

[87] PubMed/NCBI

[88] Google Scholar

[ref26] 26. Roberts HC, Denison HJ, Martin HJ, Patel HP, Syddall H, Cooper C, et al. A review of the measurement of grip strength in clinical and epidemiological studies: towards a standardised approach. Age and ageing. 2011;40(4):423–9. pmid:21624928
View Article
PubMed/NCBI
Google Scholar

[90] View Article

[91] PubMed/NCBI

[92] Google Scholar

[ref27] 27. Park JY, Lee SW. A history of repetitive cesarean section is a risk factor of anemia in healthy perimenopausal women: The Korea National Health and Nutrition Examination Survey 2010–2012. PloS one. 2017;12(11).
View Article
Google Scholar

[94] View Article

[95] Google Scholar

[ref28] 28. Kim Y. The Korea National Health and nutrition examination survey (KNHANES): current status and challenges. Epidemiology and health. 2014;36.
View Article
Google Scholar

[97] View Article

[98] Google Scholar

[ref29] 29. Park YN. Regional Disparities of Health Status in Korea: Finding from KNHANES (2007–2014). 2017.

[ref30] 30. Society MoHaWTKN. Dietary Reference Intakes for Koreans 2010. 2010.

[ref31] 31. Society MoHaWTKN. Dietary Reference Intakes for Koreans 2015. Seoul: The Korean Nutrition Society. 2015.

[ref32] 32. Chaves PH, Semba RD, Leng SX, Woodman RC, Ferrucci L, Guralnik JM, et al. Impact of anemia and cardiovascular disease on frailty status of community-dwelling older women: the Women’s Health and Aging Studies I and II. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences. 2005;60(6):729–35.
View Article
Google Scholar

[103] View Article

[104] Google Scholar

[ref33] 33. RESILIENCE B. The State Of Food Security And Nutrition In The World. Rome: Building resilience for peace and food security. 2017.

[ref34] 34. Gaskell H, Derry S, Moore RA, McQuay HJ. Prevalence of anaemia in older persons: systematic review. BMC geriatrics. 2008;8(1):1.
View Article
Google Scholar

[107] View Article

[108] Google Scholar

[ref35] 35. Adamu AL, Crampin A, Kayuni N, Amberbir A, Koole O, Phiri A, et al. Prevalence and risk factors for anemia severity and type in Malawian men and women: urban and rural differences. Population health metrics. 2017;15(1):12. pmid:28356159
View Article
PubMed/NCBI
Google Scholar

[110] View Article

[111] PubMed/NCBI

[112] Google Scholar

[ref36] 36. Mugisha JO, Baisley K, Asiki G, Seeley J, Kuper H. Prevalence, types, risk factors and clinical correlates of anaemia in older people in a rural Ugandan population. PLoS One. 2013;8(10).
View Article
Google Scholar

[114] View Article

[115] Google Scholar

[ref37] 37. Balarajan Y, Ramakrishnan U, Özaltin E, Shankar AH, Subramanian S. Anaemia in low-income and middle-income countries. The lancet. 2011;378(9809):2123–35.
View Article
Google Scholar

[117] View Article

[118] Google Scholar

[ref38] 38. Rammohan A, Awofeso N, Robitaille M-C. Addressing female iron-deficiency anaemia in india: is vegetarianism the major obstacle? ISRN Public Health. 2011;2012.
View Article
Google Scholar

[120] View Article

[121] Google Scholar

[ref39] 39. Kim Y-J, Do Han K, Cho K-H, Kim Y-H, Park Y-G. Anemia and health-related quality of life in South Korea: data from the Korean national health and nutrition examination survey 2008–2016. BMC public health. 2019;19(1):735. pmid:31196013
View Article
PubMed/NCBI
Google Scholar

[123] View Article

[124] PubMed/NCBI

[125] Google Scholar

[ref40] 40. Masukume G, Khashan AS, Kenny LC, Baker PN, Nelson G, Consortium S. Risk factors and birth outcomes of anaemia in early pregnancy in a nulliparous cohort. PloS one. 2015;10(4):e0122729. pmid:25875012
View Article
PubMed/NCBI
Google Scholar

[127] View Article

[128] PubMed/NCBI

[129] Google Scholar

[ref41] 41. Chaves PH, Ashar B, Guralnik JM, Fried LP. Looking at the relationship between hemoglobin concentration and prevalent mobility difficulty in older women. Should the criteria currently used to define anemia in older people be reevaluated? Journal of the American Geriatrics Society. 2002;50(7):1257–64. pmid:12133021
View Article
PubMed/NCBI
Google Scholar

[131] View Article

[132] PubMed/NCBI

[133] Google Scholar

[ref42] 42. Zakai NA, French B, Arnold AM, Newman AB, Fried LF, Robbins J, et al. Hemoglobin decline, function, and mortality in the elderly: the cardiovascular health study. American journal of hematology. 2013;88(1):5–9. pmid:23044913
View Article
PubMed/NCBI
Google Scholar

[135] View Article

[136] PubMed/NCBI

[137] Google Scholar

[ref43] 43. Al-Mekhlafi HM, Al-Zabedi EM, Al-Maktari MT, Atroosh WM, Al-Delaimy AK, Moktar N, et al. Effects of vitamin A supplementation on iron status indices and iron deficiency anaemia: a randomized controlled trial. Nutrients. 2014;6(1):190–206.
View Article
Google Scholar

[139] View Article

[140] Google Scholar

[ref44] 44. Gordon SR, Smith RE, Power GC. The role of endoscopy in the evaluation of iron deficiency anemia in patients over the age of 50. American Journal of Gastroenterology. 1994;89(11).
View Article
Google Scholar

[142] View Article

[143] Google Scholar

[ref45] 45. Organization WH. Iron deficiency anemia. assessment, prevention, and control. A guide for programme managers. 2001:47–62.

[ref46] 46. Jacobs A, Greenman D, Owen E, Cavill I. Ascorbic acid status in iron-deficiency anaemia. Journal of clinical pathology. 1971;24(8):694–7. pmid:5130535
View Article
PubMed/NCBI
Google Scholar

[146] View Article

[147] PubMed/NCBI

[148] Google Scholar

[ref47] 47. Cook JD, Monsen ER. Food iron absorption in human subjects. III. Comparison of the effect of animal proteins on nonheme iron absorption. The American journal of clinical nutrition. 1976;29(8):859–67. pmid:941868
View Article
PubMed/NCBI
Google Scholar

[150] View Article

[151] PubMed/NCBI

[152] Google Scholar

[ref48] 48. Hong CH, Falvey C, Harris TB, Simonsick EM, Satterfield S, Ferrucci L, et al. Anemia and risk of dementia in older adults: findings from the Health ABC study. Neurology. 2013;81(6):528–33. pmid:23902706
View Article
PubMed/NCBI
Google Scholar

[154] View Article

[155] PubMed/NCBI

[156] Google Scholar

[ref49] 49. Shavelle RM, MacKenzie R, Paculdo DR. Anemia and mortality in older persons: does the type of anemia affect survival? International journal of hematology. 2012;95(3):248–56. pmid:22351246
View Article
PubMed/NCBI
Google Scholar

[158] View Article

[159] PubMed/NCBI

[160] Google Scholar

[ref50] 50. Zakai NA, Katz R, Hirsch C, Shlipak MG, Chaves PH, Newman AB, et al. A prospective study of anemia status, hemoglobin concentration, and mortality in an elderly cohort: the Cardiovascular Health Study. Archives of internal medicine. 2005;165(19):2214–20. pmid:16246985
View Article
PubMed/NCBI
Google Scholar

[162] View Article

[163] PubMed/NCBI

[164] Google Scholar

[ref51] 51. Lucca U, Tettamanti M, Mosconi P, Apolone G, Gandini F, Nobili A, et al. Association of mild anemia with cognitive, functional, mood and quality of life outcomes in the elderly: the “Health and Anemia” study. PloS one. 2008;3(4).
View Article
Google Scholar

[166] View Article

[167] Google Scholar

[ref52] 52. den Elzen WP, Willems JM, Westendorp RG, de Craen AJ, Assendelft WJ, Gussekloo J. Effect of anemia and comorbidity on functional status and mortality in old age: results from the Leiden 85-plus Study. Cmaj. 2009;181(3–4):151–7. pmid:19635749
View Article
PubMed/NCBI
Google Scholar

[169] View Article

[170] PubMed/NCBI

[171] Google Scholar

[ref53] 53. Fukushima T, Nakano J, Ishii S, Natsuzako A, Kawachi H, Sakamoto J, et al. Influence of Hemoglobin Level on Muscle and Physical Functions, Activities of Daily Living, and Quality of Life in Patients With Hematological Malignancies. Integrative Cancer Therapies. 2019;18:1534735419842196. pmid:30947558
View Article
PubMed/NCBI
Google Scholar

[173] View Article

[174] PubMed/NCBI

[175] Google Scholar

[ref54] 54. Cho S-B. Effect of Muscular Reinforcement Exercise of Serum Albumin, WBC and Hemoglobin in the Elderly Women The journals of the Korean Society Of Sports Science. 2013;22(4):1075–81.
View Article
Google Scholar

[177] View Article

[178] Google Scholar

[ref55] 55. Payne CF, Davies JI, Gomez-Olive FX, Hands KJ, Kahn K, Kobayashi LC, et al. Cross-sectional relationship between haemoglobin concentration and measures of physical and cognitive function in an older rural South African population. J Epidemiol Community Health. 2018;72(9):796–802. pmid:29680801
View Article
PubMed/NCBI
Google Scholar

[180] View Article

[181] PubMed/NCBI

[182] Google Scholar

[ref56] 56. Eisenstaedt R, Penninx BW, Woodman RC. Anemia in the elderly: current understanding and emerging concepts. Blood reviews. 2006;20(4):213–26. pmid:16472893
View Article
PubMed/NCBI
Google Scholar

[184] View Article

[185] PubMed/NCBI

[186] Google Scholar

[ref57] 57. Hirani V, Naganathan V, Blyth F, Le Couteur DG, Seibel MJ, Waite LM, et al. Low hemoglobin concentrations are associated with sarcopenia, physical performance, and disability in older Australian men in cross-sectional and longitudinal analysis: the Concord Health and Ageing in Men project. Journals of Gerontology Series A: Biomedical Sciences and Medical Sciences. 2016;71(12):1667–75.
View Article
Google Scholar

[188] View Article

[189] Google Scholar

[ref58] 58. Thein M, Ershler WB, Artz AS, Tecson J, Robinson BE, Rothstein G, et al. Diminished quality of life and physical function in community-dwelling elderly with anemia. Medicine. 2009;88(2):107. pmid:19282701
View Article
PubMed/NCBI
Google Scholar

[191] View Article

[192] PubMed/NCBI

[193] Google Scholar

[ref59] 59. Haslam A, Hausman DB, Davey A, Cress ME, Johnson MA, Poon LW. Associations of anemia and physical function in Georgia centenarians. Journal of the American Geriatrics Society. 2012;60(12):2362. pmid:23231554
View Article
PubMed/NCBI
Google Scholar

[195] View Article

[196] PubMed/NCBI

[197] Google Scholar

[ref60] 60. Rijk JM, Roos PR, Deckx L, van den Akker M, Buntinx F. Prognostic value of handgrip strength in people aged 60 years and older: A systematic review and meta-analysis. Geriatrics & gerontology international. 2016;16(1):5–20.
View Article
Google Scholar

[199] View Article

[200] Google Scholar

[ref61] 61. Lee J, Hong YS, Park S-H, Kang KY. High serum uric acid level is associated with greater handgrip strength in the aged population. Arthritis research & therapy. 2019;21(1):73.
View Article
Google Scholar

[202] View Article

[203] Google Scholar

[ref62] 62. Antwi-Bafour S, Hammond S, Adjei JK, Kyeremeh R, Martin-Odoom A, Ekem I. A case–control study of prevalence of anemia among patients with type 2 diabetes. Journal of medical case reports. 2016;10(1):110. pmid:27142617
View Article
PubMed/NCBI
Google Scholar

[205] View Article

[206] PubMed/NCBI

[207] Google Scholar

Figures

Abstract

Background

Methods

Results

Conclusion

Introduction

Materials and methods

Study design and population

Outcomes and other variables

Measurement of handgrip strength

Measurement of Hb levels

Description of demographic and other characteristics of the study population

Measurement and classification of other variables of interest

Statistical analysis

Results

Discussion

Conclusion

References