ABSTRACT
INTRODUCTION: Frailty is highly prevalent in heart failure populations and a major risk factor for adverse drug reactions (ADRs) and adverse drug events (ADEs). This review aimed to describe the prevalence, causality and severity of ADRs or ADEs from heart failure medications among frail compared with non-frail older adults. METHODS: A systematic search of CENTRAL, MEDLINE, Embase, Ageline, CINAHL, International Pharmaceutical Abstracts, PsychInfo, Scopus, registries and citations prior to 18 May 2021 was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 checklist. Risk of bias and quality of evidence were assessed. Eligible studies included randomised controlled trials (RCTs) and observational studies of people diagnosed with heart failure, aged ≥ 65 years, with frailty defined by an objective measurement, and reported ADRs/ADEs from/with heart failure medications. RESULTS: Two reviewers screened 2419 articles; interrater reliability kappa = 0.88. Three observational studies (n = 2596), a secondary analysis of two RCTs (n = 2098) and two cohort studies (n = 498) were included in a narrative synthesis. Frail patients in randomised trials of sacubitril/valsartan, aliskiren, or enalapril had twice the risk of mortality (hazard ratio [HR] 2.09, 1.62-2.71) and hospitalisations (HR 1.82, 1.37-2.41) compared with robust patients, which may reflect responsiveness to medications and/or factors unrelated to medication use. Hospitalisations from falls, tiredness and nausea were probably attributable to digoxin and possibly preventable according to the Naranjo and Hallas scales, respectively. CONCLUSION: The potential harms from heart failure medications in frail older people are poorly studied and understood. Clinical trials and pharmacovigilance studies should include frailty as a covariate to inform medication optimisation for this vulnerable and growing population. REGISTRATION: Prospero registration number: CRD 42021253762.
