Prescribing cascades in community-dwelling adults: a systematic review

Abstract

Background: The misattribution of an adverse drug reaction (ADR) as a symptom or illness can lead to the prescribing of additional medication, referred to as a prescribing cascade. The aim of this systematic review is to identify published prescribing cascades in community-dwelling adults. Methods: Systematic review reported in line with the PRISMA guidelines and pre-registered with PROSPERO. Electronic databases (Medline (Ovid), EMBASE, PsycINFO, CINAHL, Cochrane Library) and grey literature sources were searched. Inclusion criteria: Community-dwelling adults; Risk-prescription medication; Outcomes-initiation of new medicine to ‘treat’ or reduce ADR risk; Study type-cohort, cross-sectional, case-control and case-series studies. Title/abstract screening, full-text screening, data extraction and methodological quality assessment was conducted independently in duplicate. A narrative synthesis was conducted. Results: A total of 101 studies (reported in 103 publications) were included. Study sample sizes ranged from 126 to 11,593,989 participants and 15 studies examined older adults specifically (≥60 years). Seventy-eight of 101 studies reported a potential prescribing cascade including calcium channel blockers to loop diuretic (n=5), amiodarone to levothyroxine (n=5), inhaled corticosteroid to topical antifungal (n=4), antipsychotic to anti-Parkinson drug (n=4), and acetylcholinesterase inhibitor to urinary incontinence drugs (n=4). Identified prescribing cascades occurred within three months to one year following initial medication. Methodological quality varied across included studies. Conclusion and implications: Prescribing cascades occur for a broad range of medications. ADRs should be included in the differential diagnosis for patients presenting with new symptoms, particularly older adults and those who started a new medication in the preceding 12 months. Word count: 245