The prevalence and impact of potentially inappropriate prescribing among older persons in primary care settings: multilevel meta-analysis

Background: Potentially inappropriate prescribing (PIP) may not have received as much attention in primary care settings (compared to tertiary hospital and nursing home settings), due to uncertainty about its prevalence in this healthcare setting. We conducted a systematic review with meta-analysis to summarise the prevalence of PIP specific to primary care settings and computed the population attributable risk (PAR) to estimate the impact of PIP in primary care. Method: We searched PubMed, Embase, CINAHL, Web of Science, Scopus, PsycINFO and previous review articles for studies related to 'older persons', 'primary care' and 'inappropriate prescribing'. Two reviewers selected eligible articles, extracted data and evaluated risk of bias. Multilevel meta-analysis was conducted to pool the prevalence estimates across the included studies, while meta-regression was conducted to investigate the sources of heterogeneity. Results: Of the 4,259 articles identified, we included 67 articles with 111 prevalence estimates and a total of 5,054,975 participants. Overall, PIP had a pooled prevalence of 33.3% (95% CI 29.7-37.0%). Based on population attributable risks, PIP explained 7.7-17.3% of adverse outcomes related to older persons in primary care. If current PIP prevalence is halved, 37-79 cases of adverse outcomes may potentially be prevented (per 1,000 adverse outcomes). Conclusions: The findings demonstrate the relevance and potential impact of PIP specific to primary care settings. Given the increasingly central role that primary care plays in coordinating healthcare, the findings highlight the need to prioritise PIP intervention in primary care as a key strategy to reduce iatrogenic medication-related harm among older persons in current healthcare system.