Adverse Drug Reaction-Related Hospitalizations in Elderly Australians: A Prospective Cross-Sectional Study in Two Tasmanian Hospitals

Adverse Drug Event-Related Hospital Admissions Among Australian Aged Care Residents: A Cross-Sectional Study

OBJECTIVES

To investigate the proportion, characteristics, causality, severity, preventability, and independently associated factors for adverse drug event (ADE)-related admissions in aged care residents admitted to the major public hospitals in Tasmania, Australia.

DESIGN

Retrospective cross-sectional study.

SETTING AND PARTICIPANTS

Residential aged care facility (RACF) patients aged ≥65 years who had an unplanned admission to one of the 4 Tasmanian public hospitals between July 1, 2018, and June 30, 2021.

METHODS

We accessed the medical records of RACF patients. The ADEs were initially identified via chart review and a trigger tool. Hospitalizations attributable to ADEs were then determined by expert consensus. The causality, preventability, and severity of each ADE admission were assessed using standard criteria.

RESULTS

Ninety-one residents (18.2%) of 500 randomly selected experienced potential ADE-related hospitalizations. ADEs were considered possible (n = 58, 64%) or definite/probable (n = 33, 36%). The most common ADEs were falls (n = 19, 21%), hypotension (n = 16, 18%), and confusion or delirium (n = 10, 11%). ADEs were frequently associated with renin-angiotensin system inhibitors (n = 43, 47.3%), opioids (n = 43, 47.3%), and diuretics (n = 40, 44%). Most ADEs were of moderate severity (n = 90, 99%) and considered not preventable (n = 60, 66%). Rheumatologic disease [odds ratio (OR) 1.89, 95% CI 1.09-3.30; P = .024] and previous adverse drug reaction (ADR) (OR 12.91, 95% CI 6.84-24.37; P < .001) were associated with ADE hospitalizations.

CONCLUSIONS AND IMPLICATIONS

This study highlights that hospitalization for moderately severe ADEs is common among RACF residents. Opioids and antihypertensives were the common drug classes associated with harm. Rheumatologic disease (due to opioids) and previous ADR were identified as independently associated factors, which may warrant tailored interventions.

Predictors of Adverse Drug Reaction-Related Hospitalisations Among People with Dementia: A Retrospective Case-Control Study

INTRODUCTION

Adverse drug reactions (ADRs) are common among people with dementia; however, little is known about the magnitude and predictors associated with ADR-related hospitalisation among these individuals. This study aimed to determine the magnitude, types, drugs implicated and predictors of ADRs associated with hospitalisation among people with dementia.

METHODS

This retrospective case-control study analysed medical records of individuals aged ≥ 65 years with dementia admitted to major public hospitals in Tasmania, Australia, from July 2010 to July 2021. Adverse drug reactions and implicated drugs were identified using administrative data and cross-checked with hospital medical records, with consensus reached among the research team.

RESULTS

Of the 7928 people admitted to hospital at least once within the study period, 1876 (23.7%) experienced at least one ADR-related hospitalisation. Of these, 300 case patients with 311 ADRs and 300 control patients were randomly selected. The most common types of ADRs were renal (acute kidney injury; AKI) (36.0%), followed by neuropsychiatric (17.6%), cardiovascular (16.0%) and haematological (13.1%). Diuretics, renin-angiotensin system (RAS) inhibitors and anti-thrombotics constituted the main implicated drug classes. The ADR-related hospitalisation was associated with: chronic kidney disease (CKD) (OR 8.00, 95% CI 2.63-24.28, p < 0.001), Australian-born (OR 1.62, 95% CI 1.08-2.43, p = 0.019), hypertension (OR 1.48, 95% CI 1.01-2.17, p = 0.044) and the number of medicines (OR 1.06, 95% CI 1.00-1.12, p = 0.022). Potentially inappropriate medication use and anticholinergic burden did not predict ADR-related hospitalisation.

CONCLUSIONS

These predictors could help identify the individuals at the highest risk and enable targeted interventions to be designed.

Development of a list of Australian potentially inappropriate medicines using the Delphi technique

BACKGROUND

Older people are at high risk of medicines-related harms. otentially inappropriate medicines (PIMs) list has been developed to assist clinicians and researchers to identify medicines with risks that may potentially outweigh their benefits in order to improve medication management and safety.

AIM

To develop a list of PIMs for older people specific to Australia.

METHODS

The study obtained expert consensus through the utilisation of the Delphi technique in Australia. A total of 33 experts partook in the initial round, while 32 experts engaged in the subsequent round. The primary outcomes encompass medicines assessed as potentially inappropriate, the specific contexts in which their inappropriateness arises and potentially safer alternatives.

RESULTS

A total of 16 medicines or medicine classes had one or more medicines deemed as potentially inappropriate in older people. Up to 19 medicines or medicine classes had specific conditions that make them more potentially inappropriate, while alternatives were suggested for 16 medicines or classes.

CONCLUSION

An explicit PIMs list for older people living in Australia has been developed containing 19 drugs/drug classes. The PIMs list is intended to be used as a guide for clinicians when assessing medication appropriateness in older people in Australian clinical settings and does not substitute individualised treatment advice from clinicians.

Adverse clinical outcomes associated with drug-related hospitalizations in people with dementia

BACKGROUND

This study aimed to determine the clinical impact associated with adverse drug reactions (ADRs) in patients with dementia.

RESEARCH DESIGN AND METHODS

This case-control, propensity score-matched study utilized administrative data of people with dementia admitted to major public hospitals in Tasmania, Australia, from July 2010 to December 2019.

RESULTS

Acute renal failure constituted the most common ADR. The length of hospital stay was greater for people with an ADR index admission, versus non-ADR index admission (median [IQR]: 9 [4-18] versus 6 [2-12]; p < 0.001). In-hospital mortality and combined in-hospital and post-hospital mortality within 30, 60 and 90 days were higher for those whose index admission was ADR-related (in-hospital: HR 1.40, 95% CI 1.11-1.77, p-value <0.001; 30 days: HR 1.25, 95% CI 1.05-1.49, p-value <0.001; 60 days: HR 1.27, 95% CI 1.08-1.49, p-value <0.001; 90 days: HR 1.29, 95% CI 1.10-1.50, p-value <0.001). Subsequent ADR admission within 30, 60 and 90 days of index discharge was 9 to 10 times greater for people with dementia (30 days: OR 10.0, 95% CI 6.04-16.8, p-value <0.001; 60 days: OR 8.96, 95% CI 5.57-14.4, p-value <0.001; 90 days: OR 9.31, 95% CI 5.79-14.9, p-value <0.001).

CONCLUSION

Safe prescribing and vigilant monitoring of ADRs is pivotal to mitigate adverse outcomes in people with dementia.

Opportunities for clinical decision support targeting medication safety in remote primary care management of chronic kidney disease: A qualitative study in Northern Australia

INTRODUCTION

This study aimed to identify opportunities for clinical decision support targeting medication safety in remote primary care, by investigating the relationship between clinical workflows, health system priorities, cognitive tasks, and reasoning processes in the context of medicines used in people with chronic kidney disease (CKD).

METHODS

This qualitative study involved one-on-one, semistructured interviews. The participants were healthcare professionals employed in a clinical or managerial capacity with clinical work experience in a remote health setting for at least 1 year.

RESULTS

Twenty-five clinicians were interviewed. Of these, four were rural medical practitioners, nine were remote area nurses, eight were Aboriginal health practitioners, and four were pharmacists. Four major themes were identified from the interviews: (1) the need for a clinical decision support system to support a sustainable remote health workforce, as clinicians were "constantly stretched" and problems may "fall through the cracks"; (2) reliance on digital health technologies, as medical staff are often not physically available and clinicians-on-duty usually "flick an email and give a call so that I can actually talk it through to our GP"; (3) knowledge gaps, as "it takes a lot of mental space" to know each patient's renal function and their medication history, and clinicians believe "mistakes can be made"; and (4) multiple risk factors impacting CKD management, including clinical, social and behavioural determinants.

CONCLUSIONS

The high prevalence of CKD and reliance on digital health systems in remote primary health settings can make a clinical decision support system valuable for supporting clinicians who may not have extensive experience in managing medicines for people with CKD.

The impact of hospital-based post-discharge pharmacist medication review on patient clinical outcomes: A systematic review

Background

Clinical pharmacists have been shown to identify and resolve medication related problems post-discharge, however the impact on patient clinical outcomes is unclear.

Aims

To undertake a systematic review to identify, critically appraise and present the evidence on post-discharge hospital clinics that provide clinical pharmacist medication review; report the patient clinical outcomes measured; and describe the activities of the clinical pharmacist.

Methods

Published studies evaluating a patient clinical outcome following a post-discharge hospital clinic pharmacy service were included. All studies needed a comparative design (intervention vs control or comparator). Pubmed, Embase, CINAHL, PsycnINFO, Web of Science, IPA and APAIS-Health databases were searched to identify studies. The type of clinic and the clinical pharmacist activities were linked to patient clinical outcomes.

Results

Fifty-seven studies were included in the final analysis, 14 randomised controlled trials and 43 non-randomised studies. Three key clinic types were identified: post-discharge pharmacist review alone, inpatient care plus post-discharge review and post-discharge collaborative clinics. The three main outcome metrics identified were hospital readmission and/or representation, adverse events and improved disease state metrics. There was often a mix of these outcomes reported as primary and secondary outcomes. High heterogeneity of interventions and clinical pharmacist activities reported meant it was difficult to link clinical pharmacist activities with the outcomes reported.

Conclusions

A post-discharge clinic pharmacist may improve patient clinical outcomes such as hospital readmission and representation rates. Future research needs to provide a clearer description of the clinical pharmacist activities provided in both arms of comparative studies.

Uptake of pharmacist recommendations by patients after discharge: Implementation study of a patient-centered medicines review service

BACKGROUND

Polypharmacy and potentially inappropriate medicine use is common in older people, resulting in harm increased by lack of patient-centred care. Hospital clinical pharmacy services may reduce such harm, particularly prevalent at transitions of care. An implementation program to achieve such services can be a complex long-term process.

OBJECTIVES

To describe an implementation program and discuss its application in the development of a patient-centred discharge medicine review service; to assess service impact on older patients and their caregivers.

METHOD

An implementation program was begun in 2006. To assess program effectiveness, 100 patients were recruited for follow-up after discharge from a private hospital between July 2019 and March 2020. There were no exclusion criteria other than age less than 65 years. Medicine review and education were provided for each patient/caregiver by a clinical pharmacist, including recommendations for future management, written in lay language. Patients were asked to consult their general practitioner to discuss those recommendations important to them. Patients were followed-up after discharge.

RESULTS

Of 368 recommendations made, 351 (95%) were actioned by patients, resulting in 284 (77% of those actioned) being implemented, and 206 regularly taken medicines (19.7 % of all regular medicines) deprescribed.

CONCLUSION

Implementation of a patient-centred medicine review discharge service resulted in patient-reported reduction in potentially inappropriate medicine use and hospital funding of this service. This study was registered retrospectively on 12^th July 2022 with the ISRCTN registry, ISRCTN21156862, https://www.isrctn.com/ISRCTN21156862 .

Linking Activity Theory Within User-Centered Design: Novel Framework to Inform Design and Evaluation of Adverse Drug Reaction Reporting Systems in Pharmacy

BACKGROUND

Adverse drug reactions (ADRs) may cause serious injuries including death. Timely reporting of ADRs may play a significant role in patient safety; however, underreporting exists. Enhancing the electronic communication of ADR information to regulators and between health care providers has the potential to reduce recurrent ADRs and improve patient safety.

OBJECTIVE

The main objectives were to explore the low rate of ADR reporting by community pharmacists (CPs) in Australia, evaluate the usability of an existing reporting system, and how this knowledge may influence the design of subsequent electronic ADR reporting systems.

METHODS

The study was carried out in 2 stages. Stage 1 involved qualitative semistructured interviews to identify CPs' perceived barriers and facilitators to ADR reporting. Data were analyzed by thematic analysis, and identified themes were subsequently aligned to the task-technology fit (TTF) framework. The second stage involved a usability evaluation of a commercial web-based ADR reporting system. A structured interview protocol that combined virtual observation, think-aloud moderating techniques, retrospective questioning of the overall user experience, and a System Usability Scale (SUS). The field notes from the interviews were subjected to thematic analysis.

RESULTS

In total, 12 CPs were interviewed in stage 1, and 7 CPs participated in stage 2. The interview findings show that CPs are willing to report ADRs but face barriers from environmental, organizational, and IT infrastructures. Increasing ADR awareness, improving workplace practices, and implementing user-focused electronic reporting systems were seen as facilitators of ADR reporting. User testing of an existing system resulted in above average usability (SUS 68.57); however, functional and user interpretation issues were identified. Design elements such as a drop-down menu, free-text entry, checkbox, and prefilled data fields were perceived to be extremely useful for navigating the system and facilitating ADR reporting.

CONCLUSIONS

Existing reporting systems are not suited to report ADRs, or adapted to workflow, and are rarely used by CPs. Our study uncovered important contextual information for the design of future ADR reporting interventions. Based on our study, a multifaceted, theory-guided, user-centered, and best practice approach to design, implementation, and evaluation may be critical for the successful adoption of ADR reporting electronic interventions and patient safety. Future studies are needed to evaluate the effectiveness of theory-driven frameworks used in the design and implementation of ADR reporting systems.

Potentially clinically significant drug-drug interactions in older patients admitted to the hospital: A cross-sectional study

Background: An international consensus list of potentially clinically significant drug-drug interactions (DDIs) in older people has been recently validated. Our objective was to describe the prevalence and characteristics of drug combinations potentially causing clinically significant DDIs identified in the medication history of older patients admitted to the hospital and the prevalence and characteristics of manifest DDIs-DDIs involved in adverse drug events present at hospital admission, DDIs that contributed to ADE-related hospital admissions, and DDIs involved in drug-related laboratory deviations. Methods: The data were obtained from our previous study that examined the drug-relatedness of hospital admissions to University Hospital Hradec Králové via the department of emergency medicine in the Czech Republic. Patients ≥ 65 years old were included. Drug combinations potentially causing clinically significant DDIs were identified using the international consensus list of potentially clinically significant DDIs in older people. Results: Of the 812 older patients admitted to the hospital, 46% were exposed to drug combinations potentially causing clinically significant DDIs. A combination of medications that affect potassium concentrations accounted for 47% of all drug combinations potentially causing clinically significant DDIs. In 27 cases, potentially clinically significant DDIs were associated with drug-related hospital admissions. In 4 cases, potentially clinically significant DDIs were associated with ADEs that were present at admissions. In 4 cases, the potentially clinically significant DDIs were associated with laboratory deviations. Manifest DDIs that contributed to drug-related hospital admissions most frequently involved antithrombotic agents and central nervous system depressants. Conclusion: The results confirm the findings from the European OPERAM trial, which found that drug combinations potentially causing clinically significant DDIs are very common in older patients. Manifest DDIs were present in 4.3% of older patients admitted to the hospital. In 3.3%, manifest DDIs contributed to drug-related hospital admissions. The difference in the rates of potential and manifest DDIs suggests that if a computerized decision support system is used for alerting potentially clinically significant DDIs in older patients, it needs to be contextualized (e.g., take concomitant medications, doses of medications, laboratory values, and patients' comorbidities into account).

Reporting, Monitoring, and Handling of Adverse Drug Reactions in Australia: Scoping Review

BACKGROUND

Adverse drug reactions (ADRs) are unintended consequences of medication use and may result in hospitalizations or deaths. Timely reporting of ADRs to regulators is essential for drug monitoring, research, and maintaining patient safety, but it has not been standardized in Australia.

OBJECTIVE

We sought to explore the ways that ADRs are monitored or reported in Australia. We reviewed how consumers and health care professionals participate in ADR monitoring and reporting.

METHODS

The Arksey and O'Malley framework provided a methodology to sort the data according to key themes and issues. Web of Science, Scopus, Embase, PubMed, CINAHL, and Computer & Applied Sciences Complete databases were used to extract articles published from 2010 to 2021. Two reviewers screened the papers for eligibility, extracted key data, and provided descriptive analysis of the data.

RESULTS

Seven articles met the inclusion criteria. The Adverse Medicine Events Line (telephone reporting service) was introduced in 2003 to support consumer reporting of ADRs; however, only 10.4% of consumers were aware of ADR reporting schemes. Consumers who experience side effects were more likely to report ADRs to their doctors or pharmacists than to the drug manufacturer. The documentation of ADR reports in hospital electronic health records showed that nurses and pharmacists were significantly less likely than doctors to omit the description of the drug reaction, and pharmacists were significantly more likely to enter the correct classification of the drug reaction than doctors. Review and analysis of all ADR reports submitted to the Therapeutic Goods Administration highlighted a decline in physician contribution from 28% of ADR reporting in 2003 to 4% in 2016; however, within this same time period, hospital and community pharmacists were a major source of ADR reporting (ie, 16%). In 2014, there was an increase in ADR reporting by community pharmacists following the introduction of the GuildLink ADR web-based reporting system; however, a year later, the reporting levels dropped. In 2018, the Therapeutic Goods Administration introduced a black triangle scheme on the packaging of newly approved medicines, to remind and encourage ADR reporting on new medicines, but this was only marginally successful at increasing the quantity of ADR reports.

CONCLUSIONS

Despite the existence of national and international guidelines for ADR reporting and management, there is substantial interinstitutional variability in the standards of ADR reporting among individual health care facilities. There is room for increased ADR reporting rates among consumers and health care professionals. A thorough assessment of the barriers and enablers to ADR reporting at the primary health care institutional levels is essential. Interventions to increase ADR reporting, for example, the black triangle scheme (alert or awareness) or GuildLink (digital health), have only had marginal effects and may benefit from further improvement revisions and awareness programs.

Persistence of Adverse Drug Reaction-Related Hospitalization Risk Following Discharge

This retrospective cohort study analyzed the administrative hospital records of 91,500 patients with the aim of assessing adverse drug reaction (ADR)-related hospital admission risk after discharge from ADR and non-ADR-related admission. Patients aged ≥18 years with an acute admission to public hospitals in Tasmania, Australia between 2011 and 2015 were followed until May 2017. The index admissions (n = 91,550) were stratified based on whether they were ADR-related (n = 2843, 3.1%) or non-ADR-related (n = 88,707, 96.9%). Survival analysis assessed the post-index ADR-related admission risk using (1) the full dataset, and (2) a matched subset of patients using a propensity score analysis. Logistic regression was used to identify the risk factors for ADR-related admissions within 90 days of post-index discharge. The patients with an ADR-related index admission were almost five times more likely to experience another ADR-related admission within 90 days (p < 0.001). An increased risk persisted for at least 5 years (p < 0.001), which was substantially longer than previously reported. From the matched subset of patients, the risk of ADR-related admission within 90 and 365 days more than doubled in the patients with an ADR-related index admission (p < 0.0001). These admissions were often attributed to the same drug class as the patients’ index ADR-related admission. Cancer was a major risk factor for ADR-related re-hospitalization within 90 days; other factors included heart failure and increasing age.

Drug-related hospital admissions in older adults: comparison of the Naranjo algorithm and an adjusted version of the Kramer algorithm

PURPOSE

Drug-related admissions (DRAs) are an important cause of preventable harm in older adults. Multiple algorithms exist to assess causality of adverse drug reactions, including the Naranjo algorithm and an adjusted version of the Kramer algorithm. The performance of these tools in assessing DRA causality has not been robustly shown. This study aimed to evaluate the ability of the adjusted Kramer algorithm to adjudicate DRA causality in geriatric inpatients.

METHODS

DRAs were assessed in a convenience sample of patients admitted to the acute geriatric wards of an academic hospital. DRAs were identified by expert consensus and causality was evaluated using the Naranjo and the adjusted Kramer algorithms. Positive agreement with expert consensus was calculated for both algorithms. A multivariable logistic regression analysis was performed to explore determinants for a DRA.

RESULTS

A total of 218 geriatric inpatients was included of whom 65 (29.8%) experienced a DRA. Positive agreement was 72.3% (95% confidence interval (CI), 59.6-82.3%) and 100% (95% CI, 93.0-100%) for the Naranjo and the adjusted Kramer algorithm, respectively. Diuretics were the main culprits and most DRAs were attributed to a fall (n = 18; 27.7%). A fall-related principal diagnosis was independently associated with a DRA (odds ratio 20.11; 95% CI, 5.60-72.24).

CONCLUSION

The adjusted Kramer algorithm demonstrated a higher positive agreement with expert consensus in assessing DRA causality in geriatric inpatients compared to the Naranjo algorithm. Our results further support implementation of the adjusted Kramer algorithm as part of a standardized DRA assessment in older adults.

The Extent of Medication-Related Hospital Admissions in Australia: A Review from 1988 to 2021

Introduction

Medication-related problems often lead to patient harm. This paper aims to review the Australian literature to determine the overall incidence, severity and preventability of medication-related hospital admissions, as well as providing a national estimate on their extent and cost.

Methods

The first part of the paper includes a literature search to identify studies that provided estimates of medication-related problems that caused hospital admissions. Incidence of medication-related hospital admissions, type of medication-related problem contributing to admission (e.g. adverse medicine reaction) and method used to estimate incidence (e.g. chart review) were extracted. Data on severity and preventability of the admissions were extracted where available. The second part of the paper involves use of methodological triangulation to estimate the extent and cost of medication-related hospital admission. Median estimates used to assess medication-related hospital admissions and the 2019–2020 national hospital admissions data were used to calculate the national estimate on the extent of medication-related hospital admission. Costs were also estimated.

Results

Seventeen studies provided estimates on the extent of medication-related hospital admissions as assessed using medication chart review. The median incidence of 2.5% (interquartile range [IQR] 0.6%) as a proportion of all hospital admissions suggests 275,000 hospital admissions annually in Australia are medication related. The median incidence of 9% (IQR 3.9%) of emergency admissions suggests that 270,000 admissions annually are medication related. Eight studies provided estimates of the extent of medication-related hospital admissions identified from administrative health data; the median incidence of 1.7% with an under-reporting rate of 82% suggests 280,000 hospital admissions annually are medication related. Triangulation of results suggests that at least 250,000 hospital admissions annually in Australia are medication related, with an estimated cost of 1.4 billion Australian dollars (AUD$). Five studies assessed severity, and nine studies assessed preventability. Preventability estimates suggest two-thirds of medication-related hospital admissions are potentially preventable.

Conclusions

We estimated that 250,000 hospital admissions in Australia are medication related, with an annual cost of AUD$1.4 billion to the healthcare system. Two-thirds of medication-related hospital admissions are potentially preventable.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40264-021-01144-1.

Applicability of explicit potentially inappropriate medication lists to the Australian context: A systematic review

OBJECTIVES

To determine i) the similarity of potentially inappropriate medications specified in and between existing explicit lists and ii) the availability in Australia of medications included on existing lists to determine their applicability to the Australian context.

METHODS

This systematic review identified explicit potentially inappropriate medication lists that were published on EMBASE (1974 - April 2021), MEDLINE (1946 - April 2021) and Elsevier Scopus (2004 - April 2021). The reference lists of seven previously published systematic reviews were also manually reviewed. Lists were included if they were explicit, and the most recent version and the complete list were published in English. Lists based on existing lists were excluded if no new items were added. Potentially inappropriate medications identified on each list were extracted and compared to the medications available on the Australian Register of Therapeutic Goods and Australian Pharmaceutical Benefits Schemes.

RESULTS

Thirty-five explicit published lists were identified. A total of 645 unique potentially inappropriate medications were extracted, of which 416 (64%) were available in Australia and 262 (41%) were subsided by the general Pharmaceutical Benefits Scheme. Applicability of each explicit list ranged from 50-96% according to medications available in Australia and 25-83% according to medications available under subsidy.

CONCLUSIONS

Pooling data from different lists may help to identify potentially inappropriate medications that may be applicable to local settings. However, if selecting a list for use in the Australian context, consideration should also be given to the intended purpose and setting for application.

Retrospective study of the prevalence and characteristics of adverse drug events in adults who present to an Australian emergency department

OBJECTIVE

To determine the burden, on the ED, of harm from unintentional adverse drug events (ADEs) in the community.

METHODS

A retrospective, observational study of 936 randomly selected presentations to a level 6 ED at a principal referral hospital in Brisbane, Australia, in November 2017. Clinical records were screened by a pharmacist, who identified suspected ADEs. All suspected ADEs and a random selection of presentations without ADEs were reviewed by an expert panel, which classified, by consensus: occurrence and type of ADE, contribution of ADE to presentation, severity of harm and preventability of presentation. Medication-related ED presentations (ADE-Ps) and potential ADEs were, respectively, defined as presentations directly attributable to an ADE, and medication events that occurred but did not cause the ED presentation. Descriptive data analysis was performed.

RESULTS

The median (interquartile range) age of patients was 40 (27-58) years, with 49.7% (95% confidence interval [CI] 46.5-52.9) being male. The prevalences of ADE-Ps and potential ADEs were 9.2% (95% CI 7.5-11.3) and 5.0% (95% CI 3.8-6.6), respectively. The severity of harm was classified as 'death or likely permanent harm' in 4.7% (95% CI 0.2-9.1) of ADE-Ps, 'temporary harm' (89.5%, 95% CI 83.1-96.0) and 'minimal or no harm' (5.8%, 95% CI 0.9-10.8). Most (79.1%, 95% CI 70.5-87.7) ADE-Ps were preventable.

CONCLUSIONS

There is a high burden on emergency care because of unintended medication harm in the community. Interventions to reduce such harm are likely to require a co-ordinated primary, acute and public healthcare response. The high proportion of presentations with potential ADEs indicates opportunity for harm mitigation in the ED.

Evaluation of the Direct Costs of Managing Adverse Drug Events in all Ages and of Avoidable Adverse Drug Events in Older Adults in Japan

In Japan, medical costs are increasing annually, and the increase in national medical costs, particularly in the direct cost of managing adverse drug events, is high. An in-depth understanding of these costs is important for their reduction. This study aimed to calculate the direct cost of managing adverse drug events in all ages, including older adults, and that of avoidable adverse drug events in older adults. We conducted a retrospective survey on patients aged 1 year or older who visited Gifu Municipal Hospital in Japan. We investigated and calculated the direct cost of managing adverse drug events and that of avoidable adverse drug events based on the Beers Criteria Japanese version (BCJ) and “Guidelines for medical treatment and its safety in the elderly 2015” (GMTSE-2015) in inpatients and outpatients. Among 6,504 patients, 11.1% visited the hospital or were hospitalized due to adverse drug events. The direct costs per patient with adverse drug events were 21,281 and 22,590 yen (166 and 176 euros as on September 13, 2021) for outpatients, and 853,175 and 874,582 yen (6,648 and 6,815 euros) for inpatients of all ages and older adults, respectively. The direct costs of avoidable adverse drug events per patient using drugs listed in the BCJ and GMTSE-2015 for older adults were 3,212 and 3,341 yen (25 and 26 euros) for outpatients, and 55,548 and 80,246 yen (433 and 625 euros) for inpatients, respectively. In sum, considering both inpatients and outpatients in the whole country, the direct costs of managing adverse drug events were 804.53 billion and 597.19 billion yen (6,269 million and 4,653 million euros) per year for all ages and older ages, respectively. The direct cost of avoidable adverse drug events in older adults was 83.43–258.44 billion yen (650–2,013 million euros) per year. We found that, in Japan, high medical costs are often caused by managing adverse drug events, and that the costs of avoidable adverse drug events in older adults based on the BCJ and GMTSE-2015 account for a substantial proportion of the medical cost. Therefore, by using the BCJ and GMTSE-2015, avoiding adverse drug events and reducing medical costs may be possible.

Evaluation of Renal Function Testing in Older Australian Veterans Dispensed Medicines that Require Renal Function Monitoring

INTRODUCTION

Renal function testing should be performed prior to initiating medicines that require dose adjustment in renal impairment, with ongoing monitoring in continued use, particularly in older people. There is little evidence regarding the extent to which renal function monitoring is performed in older Australians dispensed medicines requiring renal function monitoring.

OBJECTIVE

The aim of this study was to determine the extent of renal function testing in older people dispensed medicines requiring renal function monitoring.

METHODS

A retrospective analysis of administrative claims data from the Australian Government Department of Veterans' Affairs was conducted for people aged 65 years or older who were dispensed one or more medicines requiring renal function monitoring, from 1 June 2019 to 30 September 2019, to investigate the proportion of people with a claim for a pathology test that included creatinine levels in the 6-12 months before or after dispensing of a medicine requiring renal function monitoring.

RESULTS

There were 100,113 people who were dispensed at least one medicine requiring renal function monitoring during the study period, of whom 15% had a history of renal impairment and 16% had diabetes mellitus. Sixty-one percent had a claim for a test in the prior 6 months; this increased to 80% of participants with a claim for a test in the prior 12 months. The rate of claims for testing was lower in aged care facility residents compared with people living in the community (54% vs 62% in the previous 6 months; p < 0.001), and was higher in people with diabetes (75% vs 58%; p < 0.001), history of renal impairment (91% vs 59%; p < 0.001) or heart failure (77% vs 60%; p < 0.001) compared with those without these conditions.

CONCLUSION

Medicines that require renal function monitoring are commonly used in older Australians, and while the majority have claims for tests that include renal function, some are missing out.

Patient harm from cardiovascular medications

Background

Medication harm can lead to hospital admission, prolonged hospital stay and poor patient outcomes. Reducing medication harm is a priority for healthcare organisations worldwide. Recent Australian studies demonstrate cardiovascular (CV) medications are a leading cause of harm. However, they appear to receive less recognition as ‘high risk’ medications compared with those classified by the medication safety acronym, ‘APINCH’ (antimicrobials, potassium, insulin, narcotics, chemotherapeutics, heparin). Our aim was to determine the scale and type of medication harm caused by CV medications in healthcare.

Methods

A narrative review of adult (>16 years) medication harm literature identified from PubMed and CINAHL databases was undertaken. Studies with the primary outcome of measuring the incidence of medication harm were included. Harm caused by CV medications was described and ranked against other medication classes at four key stages of a patient’s healthcare journey. Where specified, the implicated medications and type of harm were investigated.

Results

A total of 75 studies were identified, including seven systematic reviews and three meta-analyses, with most focussing on harm causing hospital admission. CV medications were responsible for approximately 20% of medication harm; however, this proportion increased to 50% in older populations. CV medications were consistently ranked in the top five medication categories causing harm and were often listed as the leading cause.

Conclusion

CV medications are a leading cause of medication harm, particularly in older adults, and should be the focus of harm mitigation strategies. A practical approach to generate awareness among health professionals is to incorporate ‘C’ (for CV medications) into the ‘APINCH’ acronym.

Plain language summary

Medical students as junior adverse drug event managers facilitating reporting of ADRs

The Junior Adverse Drug Event Manager (J-ADEM) team is a multifaceted intervention focusing on real-life education for medical students that has been shown to assist healthcare professionals in managing and reporting suspected adverse drug reactions (ADRs) to the Netherlands Pharmacovigilance Centre Lareb. The aim of this study was to quantify and describe the ADRs reported by the J-ADEM team and to determine the clinical potential of this approach. The J-ADEM team consisted of medical students tasked with managing and reporting ADRs in hospitalized patients. All ADRs screened and reported by J-ADEM team were recorded anonymously, and categorized and analysed descriptively. From August 2018 through January 2020, 209 patients on two wards in an academic hospital were screened for ADR events. The J-ADEM team reported 101 ADRs. Although most ADRs (67%) were first identified by healthcare professionals and then reported by the J-ADEM team, the team also reported an additional 33 not previously identified serious ADRs. In 10% of all reported ADRs, the J-ADEM team helped optimize ADR treatment. The ADR reports were largely well-documented (78%), and ADRs were classified as type A (66%), had a moderate or severe severity (85%) and were predominantly avoidable reactions (69%). This study shows that medical students are able to screen patients for ADRs, can identify previously undetected ADRs and can help optimize ADR management. They significantly increased (by 300%) the number of ADR reports submitted, showing that the J-ADEM team can make a valuable clinical contribution to hospital care.

Hospital admissions to geriatric ward related to adverse drug events: a cross-sectional study from the Czech Republic

Background Geriatric patients represent a vulnerable population in terms of adverse drug events (ADEs). Objective The aims of this study were to determine the prevalence and preventability of hospital admissions to a geriatric ward related to ADEs, to identify medications involved in these ADEs and to describe potential preventability aspects of ADE-related admissions. Setting University Hospital Hradec Králové, Czech Republic. Methods This cross-sectional study evaluated acute hospital admissions to the geriatric ward of University Hospital Hradec Králové over a period of nine months (April-December 2017). Medication reviews were performed in order to identify ADE-related hospital admissions. Causality was assessed using the World Health Organization-Uppsala Monitoring Centre criteria. Modified Schumock-Thornton algorithm was used to assess the preventability of ADEs. Main outcome measure 9-month-prevalence of ADE-related hospital admissions. Results A total of 366 hospital admissions were included. The 9-month-prevalence of ADE-related hospital admissions was 11.75% [95% confidence interval 8.45-15.05]. Antithrombotic agents and diuretics represented the most common medication classes associated with ADEs (30.2% each). Electrolyte disturbances and gastrointestinal haemorrhages and ulcerations were the most frequently observed ADEs associated with hospital admission. Out of 43 ADE-related hospitalisations, 23 (53.5%) were considered potentially preventable. Conclusion The contribution of ADEs to hospital admission to the geriatric ward was not negligible. Our results also suggest that 53.5% of identified ADE-related admissions could be potentially prevented. This finding demonstrates just how important the research on the preventability of medication-related hospitalisations is. Further studies and implementations are still needed aiming to minimize the risk of medication-related harm.

Evaluation of the nature, severity, likelihood and preventability of medication-related hospital-acquired complications

Objective Pricing for safety and quality was introduced into Australian hospitals using a defined list of hospital-acquired complications (HACs). Medication-related HACs include drug-related respiratory complications (DRRC), haemorrhagic disorder due to circulating anticoagulants (HDDCA) and hypoglycaemia. The aim of this study was to determine the probability, severity and preventability of medication-related HACs, common contributory medications and themes, and whether medication-related HACs are a suitable data source to inform risk associated with medicines use. Methods Medical notes were reviewed retrospectively for all patients discharged from a tertiary referral metropolitan hospital between 1 July and 31 December 2018 who were flagged as experiencing a medication-related HAC. Naranjo, Hartwig's and Schumock and Thornton tools were used to assess the probability, severity and preventability of medication-related HACs. Results Over the 6-month period, 88 patients experienced a medication-related HAC. An HAC was not identified in five (5.7%) patient charts. The most common HAC was hypoglycaemia (n=59; 67%), followed by HDDCA (n=23; 26%) and DRRC (n=6; 7%). Fifteen patients (17%) flagged with a hypoglycaemia HAC were not on a medicine associated with hypoglycaemia. Overall, 6% (n=4) of HACs were severe, 72% (n=49) were moderate and 22% (n=15) were mild. Where the HAC and causal medication(s) were identified (n=68), over half were probable (51.5%, n=35) and 44.1% (n=30) were possible causes of the adverse drug reaction; only two (2.9%) were definite causes. None of the DRRC HACs was preventable. Over half the HDDCA HACs (52.2%; n=12) and almost half the hypoglycaemia HACs (46.2%; n=18) were not preventable. Common themes included appropriate anticoagulant agent, dose and monitoring, as well as periprocedural hypoglycaemic management, which considers oral intake and comorbidities. Conclusion Not all patients who experience medication-related HACs were on causative medications. Of those who were, medications were probable causal agents in over 50% of cases. Only a small number of HACs were severe and under half of medication-related HACs were preventable. What is known about the topic? The relationship between pricing for safety and quality and improvements in patient outcomes has shown mixed results. Medication-related harm is a problem within Australia and system-wide changes should be considered to improve patient care. What does this paper add? This paper adds evidence to the use of medication-related HACs as a source of data to inform risk associated with medicines use and provides details on the preventability and severity of medication-related HACs and the likelihood that medicines contribute to these complications. What are the implications for practitioners? This paper provides clinicians and policy makers details on the utility of using medication-related HACs as a measure of risk associated with medicines use. It discusses merit in using HACs as a source for quality improvement, but recommends that definitions may need to be reviewed to enhance utility.

Medication-related hospital admissions and readmissions in older patients: an overview of literature

Background The number of medication related hospital admissions and readmissions are increasing over the years due to the ageing population. Medication related hospital admissions and readmissions lead to decreased quality of life and high healthcare costs. Aim of the review To assess what is currently known about medication related hospital admissions, medication related hospital readmissions, their risk factors, and possible interventions which reduce medication related hospital readmissions. Method We searched PubMed for articles about the topic medication related hospital admissions and readmissions. Overall 54 studies were selected for the overview of literature. Results Between the different selected studies there was much heterogeneity in definitions for medication related admission and readmissions, in study population and the way studies were performed. Multiple risk factors are found in the studies for example: polypharmacy, comorbidities, therapy non adherence, cognitive impairment, depending living situation, high risk medications and higher age. Different interventions are studied to reduce the number of medication related readmission, some of these interventions may reduce the readmissions like the participation of a pharmacist, education programmes and transition-of-care interventions and the use of digital assistance in the form of Clinical Decision Support Systems. However the methods and the results of these interventions show heterogeneity in the different researches. Conclusion There is much heterogeneity in incidence and definitions for both medication related hospital admissions and readmissions. Some risk factors are known for medication related admissions and readmissions such as polypharmacy, older age and additional diseases. Known interventions that could possibly lead to a decrease in medication related hospital readmissions are spare being the involvement of a pharmacist, education programs and transition-care interventions the most mentioned ones although controversial results have been reported. More research is needed to gather more information on this topic.

Medication Regimen Complexity Index Prediction of Adverse Drug Reaction-Related Hospital Admissions

BACKGROUND

The relationship between the medication regimen complexity index (MRCI) and adverse drug reaction (ADR)-related hospital admissions has not yet specifically been investigated.

OBJECTIVE

To evaluate the MRCI and compare with medication count for prediction of ADR-related hospital admissions in older patients.

METHODS

This was a retrospective analysis of a prospectively collected convenience sample of 768 unplanned medical admissions of Australians aged 65 years old and older. The sample consisted of 115 (15.0%) ADR-related unplanned hospital admissions and 653 (85.0%) non-ADR-related unplanned medical admissions. The MRCI score was calculated from the medical records and analyzed to predict ADR-related hospital admissions.

RESULTS

The cohort had a median age of 81 years, 5 comorbidities, and 11 medications, with a slight majority of women. The MRCI score was not significantly different in patients who had ADR-related admissions compared with other medical admissions-38.5 versus 34.0, respectively; Wilcoxon Rank Sum test W = 33 522; P = 0.067. The medication count was significantly different between the ADR-related admissions compared with other medical admissions: 12 versus 10; W = 32 508; P = 0.021. However, the medication count was not a strong predictor of ADR-related admissions; unadjusted odds ratio = 1.044; 95% CI = 1.006-1.084.

CONCLUSION AND RELEVANCE

The MRCI score did not discriminate between ADR-related admissions and other medical admissions despite taking time to calculate with potential for inconsistent application. Medication count is more readily applicable with marginally greater relevance in this cohort; however, both measures do not appear to be useful when used alone for clinicians to identify patients at risk of ADRs.

Updating and validating quality prescribing indicators for use in Australian general practice

This study aims to update and validate quality prescribing indicators (QPIs) for Australian general practice. The study comprised two phases: (1) developing preliminary potential QPIs based on the 2006 National Prescribing Service (NPS) MedicineWise indicators, published literature, international indicators and guidelines, and through qualitative focus group discussions; and (2) validating the proposed QPIs through a two-round online survey using the Delphi technique. The Delphi panel included four GPs, four pharmacists and two clinical pharmacologists. The Delphi panel rated the potential QPIs for their validity, importance and feasibility using a 1-10 Likert scale. In round one, all proposed QPIs presented as 'prescribing rules' achieved high scores regarding validity, importance and feasibility No rule was eliminated and three new rules were introduced. Rules were reworded into 'prescribing indicators' for round two, which resulted in 35 indicators being accepted and two indicators being eliminated. The final QPIs also include seven drug-drug interactions, which received high scores in round one. In conclusion, 42 QPIs were nominated for use in Australian general practice, based on their validity, importance and feasibility. If implemented, these QPIs have the potential to assist in efforts to improve the quality and safety of medicines management.

Trends in adverse drug reaction-related hospitalisations over 13 years in New South Wales, Australia

BACKGROUND

Adverse drug reactions (ADR) are severe problems in global public health, and result in high mortality and morbidity. Various trends of ADR-related hospitalisations have been studied in many countries, while estimates of the trends in Australia are limited.

AIM

To examine trends in ADR-related hospitalisations in New South Wales (NSW).

METHODS

Data were extracted from the Admitted Patient Data Collection, a census of hospital separations in NSW. We estimated age-adjusted rates of ADR-related hospitalisation between 1 July 2001 and 30 June 2014 and rates by patient characteristics, main therapeutic medication groups and clinical condition groups that warranted the hospitalisation. We used the percentage change annualised estimator to evaluate rates over time.

RESULTS

A total of 315 274 NSW residents admitted for urgent care of ADR was identified. The age-adjusted rates of ADR-related hospitalisations nearly doubled and increased by 5.8% (95% CI: 5.0-6.6%) per annum, with an in-hospital death rate increase of 2.4% (1.6-3.3%). Agranulocytosis (2.7%), nausea and vomiting (2.4%) and heart failure (2.4%) were the most common conditions that led to ADR-related hospitalisations over 13 years, with acute renal failure (1.4%) recently emerging as the leading adverse condition. Participants aged between 65 and 84 years accounted for nearly half of ADR hospitalisations (45.6%), with age-adjusted rate increasing from 103.9 in 2001-2002 to 189.0 per 100 000 NSW residents in 2013-2014. Anticoagulants (13.5%) were the most common medications contributing to ADR-related hospitalisation, followed by opioid analgesics (9.6%).

CONCLUSION

ADR-related hospitalisation remains a population health burden, with significant increase over time. The findings call for continuing efforts to prevent ADR, especially among high-risk populations, such as older people.

Availability and readability of patient education materials for deprescribing: An environmental scan

AIMS

To identify and evaluate content and readability of freely available online deprescribing patient education materials (PEMs).

METHODS

Systematic review of PEMs using MEDLINE, Embase, CINAHL, PsycINFO and The Cochrane Library of Systematic Reviews from inception to 25 September 2017 to identify PEMs. Additionally, deprescribing researchers and health professionals were surveyed to identify additional materials. Known repositories of materials were searched followed by a systematic Google search (22-28 January 2018). Materials were evaluated using an approach informed by the Patient Education Material Assessment Tool and the International Patient Decision Aids Standards Inventory. Readability of text-based materials was assessed using the US-based Gunning-Fog Index and Flesch-Kincaid Grade level.

RESULTS

Forty-eight PEMs were identified. PEMs addressing deprescribing of medications for symptom control (81%) were most common. Preventative medications were rarely addressed and material (39%) focused on older people. Only 37% of PEMs provided information about both potential benefits (e.g. reducing risk of side effects) and harms (e.g. withdrawal symptoms, increased risk of disease) of deprescribing, while 40% focussed on benefits only. Readability indices indicated an average minimum reading level of Grade 12. Option Grids and Decision Aids (mean reading level below Grade 10) were most suitable for people with average literacy levels.

CONCLUSIONS

Over 1/3 of deprescribing PEMs present potential benefits and harms of deprescribing indicating most of the freely available materials are not balanced. Most PEMs are pitched above average reading levels making them inaccessible for low health literacy populations.

Characterization and preventability of adverse drug events as cause of emergency department visits: a prospective 1-year observational study

Background

Adverse drug events (ADEs) are a significant cause of emergency department (ED) visits, with a major impact on healthcare resource utilization. A multicentre observational study, aimed to describe frequency, seriousness and preventability of ADEs reported in four EDs, was performed in Sicily (Italy) over a 1-year period.

Methods

Two trained monitors for each ED supported clinicians in identifying ADEs of patients admitted to EDs between June 1st, 2013 and May 31st, 2014 through a systematic interview of patients or their caregivers and with an additional record review. A research team analyzed each case of suspected ADE, to make a causality assessment applying the Naranjo algorithm and a preventability assessment using Schumock and Thornton criteria.

Absolute and percentage frequencies with 95% confidence interval (CI) and medians with interquartile ranges (IQR) were estimated. Logistic regression models were used to evaluate independent predictors of serious and certainly preventable ADEs.

Results

Out of 16,963 ED visits, 575 (3.4%) were associated to ADEs, of which 15.1% resulted in hospitalization. ADEs were classified as probable in 45.9%, possible in 51.7% and definite in 2.4% of the cases. Moreover, ADEs were considered certainly preventable in 12.3%, probably preventable in 58.4%, and not preventable in 29.2% of the cases. Polytherapy influenced the risk to experience a serious, as well as a certainly preventable ADE. Whilst, older age resulted an independent predictor only of serious events. The most common implicated drug classes were antibiotics (34.4%) and anti-inflammatory drugs (22.6%). ADEs due to psycholeptics and antiepileptics resulted preventable in 62.7 and 54.5% of the cases, respectively. Allergic reactions (64%) were the most frequent cause of ADE-related ED visits, followed by neurological effects (10.2%) that resulted preventable in 1.9 and 37.3% of the cases, respectively.

Conclusion

ADEs are a frequent cause of ED visits. The commonly used antibiotics and anti-inflammatory drugs should be carefully managed, as they are widely involved in mild to severe ADEs. Polytherapy is associated with the occurrence of serious, as well as certainly preventable ADEs, while older age only with serious events. A greater sensitivity to drug monitoring programs among health professionals is needed.

Potential Drug-Drug Interactions in a Cohort of Elderly, Polymedicated Primary Care Patients on Antithrombotic Treatment

INTRODUCTION

Drug-drug interactions (DDIs) are an important risk factor for adverse drug reactions. Older, polymedicated patients are particularly affected. Although antithrombotics have been detected as high-risk drugs for DDIs, data on older patients exposed to them are scarce.

METHODS

Baseline data of 365 IDrug study outpatients (≥ 60 years, use of an antithrombotic and one or more additional long-term drug) were analyzed regarding potential drug-drug interactions (pDDIs) with a clinical decision support system. Data included prescription and self-medication drugs.

RESULTS

The prevalence of having one or more pDDI was 85.2%. The median number of alerts per patient was three (range 0-17). For 58.4% of the patients, potential severe/contraindicated interactions were detected. Antiplatelets and non-steroidal anti-inflammatory drugs (NSAIDs) showed the highest number of average pDDI alert involvements per use (2.9 and 2.2, respectively). For NSAIDs, also the highest average number of severe/contraindicated alert involvements per use (1.2) was observed. 91.8% of all pDDI involvements concerned the 25 most frequently used drug classes. 97.5% of the severe/contraindicated pDDIs were attributed to only nine different potential clinical manifestations. The most common management recommendation for severe/contraindicated pDDIs was to intensify monitoring. Number of drugs was the only detected factor significantly associated with increased number of pDDIs (p < 0.001).

CONCLUSION

The findings indicate a high risk for pDDIs in older, polymedicated patients on antithrombotics. As a consequence of patients' frequently similar drug regimens, the variety of potential clinical manifestations was small. Awareness of these pDDI symptoms and the triggering drugs as well as patients' self-medication use may contribute to increased patient safety.

Repeat Adverse Drug Reaction-Related Hospital Admissions in Elderly Australians: A Retrospective Study at the Royal Hobart Hospital

BACKGROUND

Adverse drug reactions are a major cause of hospital admissions in older individuals, with the majority potentially preventable. Despite the apparent magnitude of this problem, little is known about rates of repeat admission to hospital as a result of adverse drug reactions.

OBJECTIVES

The objectives of this study were to investigate the occurrence of repeat adverse drug reaction-related hospital admissions in elderly patients within 12 months of an adverse drug reaction-related admission to a medical ward and whether a validated adverse drug reaction score could be useful in identifying patients at higher risk of a repeat adverse drug reaction-related hospitalisation.

METHODS

This retrospective study followed elderly participants who were hospitalised with an adverse drug reaction from our earlier study [the PADR-EC (Prediction of Hospitalization due to Adverse Drug Reactions in Elderly Community-Dwelling Patients) study] to identify repeat adverse drug reaction-related hospital admissions within 12 months of discharge. The PADR-EC score is the sum of points assigned to five significant predictors of adverse drug reaction-related hospitalisation: antihypertensive use, renal failure, dementia, inappropriate anticholinergic use and drug changes in the preceding 3 months. The causality, preventability and severity of each adverse drug reaction-related repeat admission within the 12-month follow-up were assessed.

RESULTS

Adverse drug reaction-related repeat admissions occurred after 13.4% (n = 15) of 112 adverse drug reaction-related index admissions. Patients with a repeat adverse drug reaction-related admission had significantly higher PADR-EC scores at discharge of their index admission (median PADR-EC score 7, interquartile range 7-9) than patients who were not readmitted (median PADR-EC score 7, interquartile range 5-7, p = 0.034). Most (73.3%) adverse drug reaction-related repeat admissions were considered 'preventable'. Adverse drug reaction severity was 'moderate' in all cases. Renal disorders (44.4%) represented the most common adverse drug reactions and the most frequently implicated drug classes were diuretics (44.8%). All adverse drug reaction-related repeat admissions were found to be 'probable'.

CONCLUSIONS

One in eight elderly patients hospitalised because of an adverse drug reaction had a repeat admission for an adverse drug reaction within 12 months of discharge. The PADR-EC score could potentially be used at hospital discharge to prioritise patients for interventions to prevent subsequent adverse drug reaction-related hospital admissions.

Antihypertensive-related adverse drug reactions among older hospitalized adults

Background Antihypertensive medications are commonly used for a wide range of indications, yet it is unknown to what extent older adults are at risk of adverse drug reactions (ADRs) associated with their antihypertensive medication use. Objective The aim of this study was to determine the prevalence and characteristics of antihypertensive-related ADRs on hospital admission. Setting Metropolitan teaching hospital in Sydney, Australia. Method A retrospective cross-sectional audit of 503 older patients (≥ 65 years) admitted to hospital was conducted. Potential ADRS were identified from the medical record. Two independent clinical pharmacists reviewed each potential ADR using validated tools for causality, severity, preventability and contribution to hospitalization. Characteristics associated with an increased ADR risk among antihypertensive users were identified via logistic regression. Main outcome measure Antihypertensive related ADRs. Results Antihypertensives were used on admission by 68% of the cohort and the prevalence of 'definite/probable' antihypertensive-related ADRs among antihypertensive users was 16.4%. Antihypertensive medications were associated with a threefold ADR risk (OR = 3.09, 95% CI 1.85-5.16). Angiotensin II Receptor Blockers (ARB), impaired renal function, recent medication changes and previous history of allergy or ADR were all associated with an increased risk of experiencing an ADR. Conclusions ADRS associated with antihypertensive medicines were relatively common among older adults admitted to hospital. Increased awareness of those older persons who are most at risk of experiencing an antihypertensive-related ADR in the clinical setting may lead to early detection and minimization of ADR associated harms.