Abstract
OBJECTIVE: To summarize evidence from published systematic reviews evaluating the effect of polypharmacy interventions on clinical and intermediate outcomes. It also summarizes the adverse events that may occur as a result of these interventions. DATA SOURCES: A literature search was conducted using the electronic databases MEDLINE, Embase, CINAHL, Cochrane Central, and Cochrane Database of Systematic Reviews (PROSPERO registration number: CRD42018085767). STUDY SELECTION: The search yielded a total of 21,329 citations, of which 619 were reviewed as full text and 5 met the selection criteria. SYNTHESIS: The polypharmacy interventions were found to produce statistically significant reductions in potentially inappropriate prescribing and improved medication adherence; however, the observed effects on clinical and intermediate outcomes were inconsistent. None of the included reviews reported any significant benefit of polypharmacy interventions for quality-of-life outcomes. Specific to health care utilization and cost, polypharmacy interventions reduced health care resource usage and expenditure. The reviews reported no differences in adverse drug events between polypharmacy interventions and usual care groups. The overall certainty of evidence was reported as low to very low across included reviews. CONCLUSION: Polypharmacy interventions are associated with reductions in potentially inappropriate prescribing and improvements in medication adherence. However, there is limited evidence of their effectiveness for clinical and intermediate outcomes.