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The impacts of medication shortages on patient outcomes: A scoping review

  • Jonathan Minh Phuong ,

    Roles Conceptualization, Data curation, Formal analysis, Investigation, Visualization, Writing – original draft, Writing – review & editing

    jphu0360@uni.sydney.edu.au

    Affiliation Sydney Pharmacy School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia

  • Jonathan Penm,

    Roles Conceptualization, Formal analysis, Methodology, Supervision, Visualization, Writing – review & editing

    Affiliation Sydney Pharmacy School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia

  • Betty Chaar,

    Roles Conceptualization, Formal analysis, Methodology, Supervision, Visualization, Writing – review & editing

    Affiliation Sydney Pharmacy School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia

  • Lachlan Daniel Oldfield,

    Roles Formal analysis, Writing – review & editing

    Affiliation Sydney Pharmacy School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia

  • Rebekah Moles

    Roles Conceptualization, Formal analysis, Investigation, Methodology, Project administration, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing

    Affiliation Sydney Pharmacy School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia

Abstract

Background

In recent years, medication shortages have become a growing worldwide issue. This scoping review aimed to systematically synthesise the literature to report on the economic, clinical, and humanistic impacts of medication shortages on patient outcomes.

Methods

Medline, Embase, Global Health, PsycINFO and International Pharmaceutical Abstracts were searched using the two key concepts of medicine shortage and patient outcomes. Articles were limited to the English language, human studies and there were no limits to the year of publication. Manuscripts included contained information regarding the shortage of a scheduled medication and had gathered data regarding the economic, clinical, and/or humanistic outcomes of drug shortages on human patients.

Findings

We found that drug shortages were predominantly reported to have adverse economic, clinical and humanistic outcomes to patients. Patients were more commonly reported to have increased out of pocket costs, rates of drug errors, adverse events, mortality, and complaints during times of shortage. There were also reports of equivalent and improved patient outcomes in some cases.

Conclusions

The results of this review provide valuable insights into the impact drug shortages have on patient outcomes. The majority of studies reported medication shortages resulted in negative patient clinical, economic and humanistic outcomes.

Introduction

Medicines are an essential part of medical care, which improve patients' health and quality of life [1]. In the modern era, with the advancement of manufacturing, distribution, and transport technologies, one would expect medication shortages to be a minor issue, where supply is quickly resolved without negative ramifications to patient health and quality of life. Unfortunately, this is not the case. Medication shortages have been described as a growing worldwide issue in recent years [2].

There are various definitions of medication shortages, often also called “drug shortages”. The University of Utah Drug Information Service defines a shortage as "A supply issue that affects how pharmacies prepare and dispense a product or that influences patient care when prescribers must choose an alternative therapy because of supply issues” [3]. The US Food and Drug Administration (FDA) defines medication shortages as "a period of time when the demand or projected demand for the drug … exceeds the supply of the drug" [3]. Despite minor differences in definitions, if a medicine is not available for the patient at the time they require treatment, regardless of the reason, the patient will either have to go without treatment, choose an alternative treatment, delay treatment, or incur some difficulty by trying to obtain treatment via another source.

Multiple reasons have been cited as to why drug shortages occur. These include quality manufacturing issues, insufficient quantities of raw materials, regulatory issues, discontinuation of products from the market, procurement issues, business decisions and natural disasters [47]. In order to overcome the impact of shortages on the health system and patients, various strategies have been implemented such as changes to policies, increased reporting and expedited approval [8]. In fact, some of these strategies have worked to a small extent as the FDA reported a decrease in drug shortages in recent years from 117 in 2012 to 23 in 2016 [6]. Despite these efforts, at the time of writing this manuscript, there were 91 medications listed to be in shortage on the FDA website, [9] and the University of Utah Drug Information Services showed a stable trend of around 150 shortages each year [10]. In Australia, a snapshot by the Society of Hospital Pharmacists Australia reported 365 different medication shortages on a single day in 2016 [11]. These numbers indicate just how complex this global problem is and that further work needs to be done to ensure access to essential medicines when they are required.

As alluded to, the ramifications of medication shortages have vast implications for both the health care system, health institutions and workforce. Importantly, medication shortages have the potential to impact patient outcomes. The literature has reported that shortages have put economic burdens on the health system, interfered with patient care, and have led to patient dissatisfaction [12, 13]. Medication shortages have also been reported to increase patient out of pocket costs [13, 14] and most alarmingly they have led to adverse patient events including mortality, treatment changes, inferior treatment, and medication errors [13, 15]. Some positive or equivalent outcomes have emerged from using alternative treatments as workarounds [16]. Despite these reports, there have been no reviews exploring the economic, clinical and humanistic impacts of medication shortages on patient outcomes. Therefore, this scoping review aimed to systematically synthesise the literature to report on the economic, clinical, and humanistic impacts of medication shortages on patient outcomes.

Methods

Search

Utilising the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol [17], this scoping review gathered research manuscripts that reported patient outcomes related to medicines shortages (S1 File). Medline, Embase, Global Health, PsycINFO and International Pharmaceutical Abstracts were searched using the two key concepts of medication shortage and patient outcomes (S2 File). Searches were limited to the English language, human studies and there were no limits to the year of publication.

Study selection

After the removal of duplicates, conference abstracts, editorials, and opinion pieces, titles and abstracts were scanned for relevance. Manuscripts were included if they were about a shortage of a scheduled medicine, had gathered data regarding the economic, clinical, and/or humanistic outcomes of drug shortages on human patients, and followed the IMRAD format [18] (containing an introduction, methods, results and discussion section). Manuscripts were excluded if the impact to patients was not attributed to shortages.

Data extraction

Study location, data collection method, the medicines(s) affected by the shortage, and patient outcomes were extracted from each manuscript. Economic outcomes were those that directly affected a patients’ finances as a consequence of the shortage; clinical outcomes were defined as a change in a patient's health status due to a drug shortage. Subsets of clinical outcomes included mortality; adverse drug reactions; drug errors; changes in hospitalisation, such as increased length of stay or readmission; and other clinical outcomes, e.g. changes in a measured parameter such as blood pressure. Humanistic outcomes were defined as non-clinical and non-economic impacts on patients such as quality of life, satisfaction and concerns as a result of the shortage.

Results

A total of 230 unique articles were found after the initial search. After application of inclusion and exclusion criteria, 40 manuscripts were included in the final review (Fig 1). These 40 studies all contained data regarding economic, clinical, and/or humanistic impacts of drug shortages on patients.

Included manuscripts were from 11 countries worldwide. The majority of manuscripts were from North America (n = 28), followed by Africa (n = 5), Europe (n = 3) and the Western Pacific (n = 3) the remaining manuscript was from Saudi Arabia in the Middle East. All manuscripts were observational studies, retrospective cohort studies (n = 19) and surveys (n = 15). Studies gathered information from patient charts (n = 21), reports of healthcare professionals (n = 19), and patient reports (n = 3). Some studies used multimodal methods to gather data on patient outcomes due to shortages.

There were 19 studies which reported on an individual medicine, of these 15 were unique medicines. Three medicines were reported multiple times: daunorubicin (n = 2), piperacillin-tazobactam (n = 2) and propofol (n = 3). In 13 studies, a group of medicines was reported, of these, there were seven unique groups. The most common groupings were: oncology medicines (n = 6), antimicrobials (n = 2). Other groups were anaesthetics, antihypertensives, antiretrovirals, paediatric medicines and glaucoma medicines. Eight studies did not specify a particular medicine in shortage, instead they reported on medication shortages in general.

Economic outcomes

Economic outcomes due to medication shortages were reported in five studies (Table 1). The only economic outcome reported was patient out of pocket (OOP) costs. All five studies reported an increase in patient OOP costs [7, 1922].

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Table 1. Economic outcomes of drug shortages on patients.

https://doi.org/10.1371/journal.pone.0215837.t001

Clinical outcomes

Clinical outcomes due to medication shortages were reported in 38 studies (Table 2). Mortality was reported in 16 studies. Of these, ten reported increased mortality [5, 13, 2330], and five reported equivalent mortality [3135]. One study, Abdelrahman et al. [36] reported both increased and equivalent mortality, the majority of physicians agreed or were neutral regarding the statement that drug shortages resulted in patient deaths, however, there was also a proportion of physicians which disagreed. Medication classes that were commonly involved in poor patient outcomes during shortages included antimicrobials [28, 33, 3739] and oncology medicines [2427, 31, 32, 4042].

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Table 2. Clinical outcomes of drug shortages on patients.

https://doi.org/10.1371/journal.pone.0215837.t002

Adverse drug reactions (ADRs) were reported in 24 studies. Of these, 14 reported increased ADRs [7, 13, 22, 2226, 28, 33, 37, 38, 40, 43, 44], six reported equivalent incidences of ADRs [8, 31, 32, 35, 41, 45], and one reported decreased ADRs due to the shortages [16]. Three studies reported multiple impacts on ADRs. As above, the study by Abdelrahman et al. [36] reported both increased and equivalent ADRs, as it gathered physicians’ perspectives and there was a proportion of respondents who agreed, disagreed or were neutral with the statements in the survey. Hall et al. [29] reported both increased and decreased ADRs, where anaesthetic shortages were reported to increase post-operative complications, and fentanyl removal from epidurals resulted in less pruritis. Mendez et al. [39] reported both equivalent and decreased ADRs where piperacillin-tazobactam shortage did not affect the rate of vancomycin-resistant enterococci infections, the rate of Clostridium difficile infection decreased.

Drug errors were reported in nine studies. Eight of these reported an increase in drug errors [13, 19, 23, 24, 26, 29, 42, 46]. The study by Abdelrahman et al. [36] reported both increased and equivalent drug errors because it reported physicians’ perspectives.

Changes in hospitalisation status were reported in 11 studies. Of these seven studies reported increased hospitalisation [5, 13, 28, 29, 33, 37, 47], three reported equivalent hospitalisation [31, 35, 48], and one reported decreased hospitalisation [8].

A range of other clinical outcomes were also measured and reported in studies including drug-resistant mutations [49], use of inferior treatments [50, 51], rationing of medications [35, 52], quality of patient care [12, 13, 23], mechanical ventilation [48], and seizure frequency [22]. These can be seen in Table 2.

Humanistic outcomes

Humanistic outcomes due to shortages were reported in eight studies (Table 3). Patient complaints were reported in three studies [5, 13, 29] and increased travel time was reported in four studies [13, 24, 26, 47]. Other outcomes reported included patients being frustrated, angry and feeling like a burden to themselves and caregivers. These can be seen in Table 3. One study by Lukmanji et al. [22] used a quantitative quality of life (QOL) tool which found no statistical difference between participants QOL pre- and during-shortage. The same study also collected qualitative quotes from participants,—“When I first found out about the shortage I panicked and I was immediately worried that I was going to run out of pills and thought far ahead–I have a problem with catastrophic thinking. I thought far ahead about if I ran out of [Frisium] and if I have a seizure and worried about losing my license and house and then losing AISH [financial support]. When it got to that point I thought about killing myself. The anxiety got that bad” demonstrating that there were some impacts on patients’ humanistic outcomes not captured via the QOL tool.

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Table 3. Humanistic outcomes of drug shortages on patients.

https://doi.org/10.1371/journal.pone.0215837.t003

Discussion

The results of this review demonstrate that medication shortages are a complex, global phenomenon, which affects patients' economic, clinical, and humanistic outcomes. While drug shortages have been reported to be a global issue which are reported by 99% of pharmacists each year [19], there were only 40 studies gained from our comprehensive search strategy which reported patient outcomes that met inclusion criteria for review. The reasons for such underreporting may be due to the problem being so ubiquitous that no one has ever really questioned it, or that drug shortages are a new phenomenon which has not yet been fully explored, or that clinician time is spent dealing with workarounds, and time for research, audits, documentation and follow-up is not available. Even though research evidence of patient consequence may be an underreported phenomenon, this review highlighted that regardless of the medicine that was in short supply, the majority of patient outcomes resulting from the shortage were disadvantageous to patients’ clinical, economic and humanistic outcomes.

With respect to economic outcomes, these were only reported in five studies. This could be attributed to lack of economic data generated as the majority of studies focused on clinical outcomes and used retrospective chart analysis for information. Economically, drug shortages in all reported instances increased OOP costs for patients. These increased costs were attributed to factors such as switching brand of the same medicine, switching to an alternative medicine, and expenses such as fuel for travelling further distances to acquire medicines. Patient OOP expenses were the only economic outcome reported, perhaps this may be due to health research being biased towards clinical outcomes or that it is difficult to capture the actual economic cost of drug shortages. No studies reported other economic outcomes such as productivity costs (e.g. time off work) or cost-utility, demonstrating that there may be a lack of sophistication in analysing the actual economic impact that shortages have on patients [53].

It should be noted that other economic considerations were reported in some studies such as institutional costs. One institution reported having to pay 300–500% more for shortage medicines [46], another reported having to pay up to 1704% more for an alternative agent [40]. Furthermore, studies reported having to have dedicated staff to manage shortages [30]. As many of these studies were from the USA, it is unknown if or how these costs would be passed onto the patients directly or their insurance companies and affect premiums and as these other economic considerations were not reported to affect patients directly, we can only theorise their impacts. Furthermore, different countries have different healthcare systems, where the costs of access to medicines during times of shortage may vary.

Clinical outcomes were reported in the majority of studies. However, these were generally retrospective reviews of data from patient records. Data gathered via this medium included specific patient outcomes related to the treatment, such as rates of infection or seizures. Other outcomes such as adverse drug reactions and drug errors were also often gathered via this retrospective audit of notes. Utilising this modality may have its limitations, as clinical documentation may not always be complete [54]. For example, studies which reported only on adverse events did not give a full depiction as to whether the alternative treatments were beneficial in treating the primary condition [38, 39]. The other method utilised to report the clinical outcomes of drug shortages were self-report mainly from clinicians via survey or semi-structured interviews. These data collection methods may also lead to a problematic interpretation of the actual impact of the medication shortages on patient outcomes, as they may generate recall bias, particularly if participants were surveyed some-time after the shortage. Furthermore, survey questions may be leading, inflating the perceived outcomes of the shortage, also, these methods are only reporting perceptions of the impact of the shortage on the patient from the lens of the health professional and not from the patients themselves.

Rates of adverse events were reported in 20 studies. The majority of reports indicated an increase in adverse events such as increased toxicity of the alternative treatment. Interestingly, two studies reporting on the impact of piperacillin-tazobactam shortages on secondary Clostridium difficile infection and had conflicting results. One study reported an increased rate of Clostridium difficile infection [38], whereas the other, a decrease [39]. The changes in infection rate and adverse events may be attributed to the alternative therapy used, rather than the shortage itself. Thus, in order to use data from shortages, comprehensive clinical documentation is needed to guide future research and treatment protocols, particularly if improved responses to alternative treatments are reported. Interestingly, many of the studies reviewed were regarding drug shortages of antimicrobials or oncology medicines. These shortages may be more likely to be studied, due to the perceived importance placed on these medicines. However due to the heterogenous reporting of patient outcomes across studies, few comparisons of results can be compared.

Drug shortages were also associated with increased medication errors. This was attributed to factors such as unfamiliarity with alternative agents. Pharmacy staff noted in a 2003 study reporting on 109 shortages at one institute that in 54% of shortages clinicians may be unfamiliar with the alternative product regarding its mechanism of action, adverse effects, or interactions [55].

Lack of medication availability causing death is the most severe consequence of drug shortages and mortality was reported in 18 studies. Some of these studies reported few deaths, whereas others could attribute hundreds. In a 5-year retrospective cohort study of 27,835 patients with septic shock during a norepinephrine shortage, alternative vasopressor use resulted in an increased mortality of 3.7% (p = 0.3) [30]. In contrast to this long-term comparative study, others directly gathered physician perspectives on the relationships between drug shortages and mortality. This was the case in the study by Abdelrahman et al. where approximately 1/3 of physicians stated that shortages caused death, 1/3 said they did not, and 1/3 responded neutrally on the survey tool [36]. These heterogeneous methods used to report the impact of shortages, again making it difficult to draw firm conclusions on true impacts, and more comprehensive studies comparing those receiving no drug, or alternative treatment are required to highlight the full clinical consequence of shortages.

In addition to clinical and economic outcomes, it has been stated that health care is more than just treating a condition, and humanistic outcomes such as quality of life is also an important measure of successful health care [56]. However, in our review, we found only ten studies which reported humanistic outcomes. These studies reported patients having difficulty accessing their medications, patients complaining to health professionals about drug shortages, patients having to be transferred to other facilities to find suitable health care, and patients being anxious and distressed. One study used a quantitative tool to measure QOL during a clobazam shortage and reported no significant difference [22]. However, within the same study, there were extracts from patient interviews which suggest otherwise. Previous literature has also reported that often QOL tools may not be sensitive enough to capture the true impact of an intervention on the patient and that other tools measuring humanistic outcomes may need to be developed [56]. It is doubtful that this review captured the entire range of humanistic impacts of drug shortages, however, those reported predominantly seem to be negatively affecting the patient. Further research investigating humanistic outcomes and the patients’ perspective of how drug shortages affect them is warranted in order to create holistic solutions to the shortage problem.

It has been commonly reported that drug shortages are a global problem. However, the majority of the studies included in this review were from developed nations such as the United States. The World Health Organisation reports that up to a third of the world’s population does not have access to medications, where this rate is even higher in low-to-middle income countries [57], yet these nations are not well represented in this review. This prompts the question as to whether the impacts of drug shortages may differ in these nations. Due to the majority of studies reporting outcomes of shortages in developed countries, the results found in this review may not be generalisable to developing countries.

Due to the dearth of research literature reporting patient outcomes due to medication shortages, as well as the lack of homogeneity in the tools used to report these outcomes, this scoping review provides a snapshot of some of the economic, clinical and humanistic outcomes that may result from medication shortages. However, it may not allow one to make any firm conclusions about their true impact on patient outcomes.

It should be noted that much of the data comes from study types of low research validity, as the majority of studies were retrospective cohort studies or surveys. While cohort studies are observations of real outcomes of shortages, they may lack rigour. Surveys of healthcare professionals were the other common research method utilised. As mentioned, these are subject to biases and only gather the perspectives of the clinicians and not the patients themselves who are experiencing the treatment changes due to the shortage. Only one study in this review, actually asked patients themselves about the impacts they faced as a result of their medication shortage [22]. Additionally, the researchers may have had preconceived ideas of what data to record and may not have reported the full impact of the shortage for each individual involved. We believe a recording method for shortages should be created in order to capture the entire clinical, economic, and humanistic picture of drug shortages for the future. Due to the nature and small numbers of these manuscripts, the risk of bias was not assessed in this review.

This scoping review therefore had both strengths and limitations. This is one of the first reviews that we are aware of attempting to synthesise the literature on the consequences of drug shortages specifically on patient outcomes. The systematic and comprehensive search strategy in many academic databases and the use of two authors applying the inclusion and exclusion criteria across all articles lead us to believe that we have captured most of the research data in this field. However, limiting the search to English only and not searching grey literature may mean that some studies (and accounts) have been missed. In addition, this review did not attempt to extract the root cause of these shortages or the strategies that have been put in place to overcome drug shortages when they occur. Lists of root causes and strategies can often be found on National Health System websites [6, 58]. Furthermore, it did not attempt to make any comparisons between different health systems, and as already stated, much of the data was from developed nations and studies reporting patient outcomes in other parts of the world were lacking.

Whilst it was difficult to combine outcomes from different study types, this review highlights the need for creation of guidelines or a tool to record the impacts of drug shortages for future in order to allow better comparison and reporting of meaningful outcomes. More structured data should be gathered during times of shortage, which in turn can be used to guide further research and treatment protocols. Particularly, the economic and humanistic impact of medication shortages needs to be addressed.

Conclusion

The results of this review provide valuable insights into the impact drug shortages have on patient outcomes. The majority of studies reported medication shortages resulted in negative patient clinical, economic and humanistic outcomes.

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