Prevalence and predictors of medication non-Adherence among people living with multimorbidity: A systematic review and meta-Analysis

Abstract

Objectives This systematic review aimed to describe medication non-Adherence among people living with multimorbidity according to the current literature, and synthesise predictors of non-Adherence in this population. Methods A systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses. PubMed, EMBASE, CINAHL and PsycINFO were searched for relevant articles published in English language between January 2009 and April 2019. Quantitative studies reporting medication non-Adherence and/or predictors of non-Adherence among people with two or more chronic conditions were included in the review. A meta-Analysis was conducted with a subgroup of studies that used an inclusive definition of multimorbidity to recruit participants, rather than seeking people with specific conditions. Remaining studies reporting prevalence and predictors of non-Adherence were narratively synthesised. Results The database search produced 10 998 records and a further 75 were identified through other sources. Following full-Text screening, 178 studies were included in the review. The range of reported non-Adherence differed by measurement method, at 76.5% for self-report, 69.4% for pharmacy data, and 44.1% for electronic monitoring. A meta-Analysis was conducted with eight studies (n=8949) that used an inclusive definition of multimorbidity to recruit participants. The pooled prevalence of non-Adherence was 42.6% (95% CI: 34.0-51.3%, k=8, I 2 =97%, p<0.01). The overall range of non-Adherence was 7.0%-83.5%. Frequently reported correlates of non-Adherence included previous non-Adherence and treatment-related beliefs. Conclusions The review identified a heterogeneous literature in terms of conditions studied, and definitions and measures of non-Adherence used. Results suggest that future attempts to improve adherence among people with multimorbidity should determine for which conditions individuals require most support. The variable levels of medication non-Adherence highlight the need for more attention to be paid by healthcare providers to the impact of multimorbidity on chronic disease self-management. PROSPERO registration number CRD42019133849.