Positive Affect and Medication Adherence in Chronic Conditions: A Systematic Review

Objective: This review aims to inform research and clinical care on the current state of knowledge on the relationship between positive affect and medication adherence. Method: Searches were carried out in PsycINFO, PubMed MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL, and Embase. There were no limits on study type, publication date, language, or participant demographics. Studies reporting a relationship between positive affect and medication adherence were eligible for inclusion if positive affect was measured prior to or concurrently with medication adherence. Results: Nine studies met inclusion criteria. All studies were prospective cohort or cross-sectional and examined positive affect and medication adherence in people living with HIV or cardiovascular conditions. The majority of results indicated positive associations between positive affect and medication adherence, with Cohen's d effect sizes ranging from -0.40 to 1.27. Conclusions: Consistent with previous theoretical work, this systematic review provides evidence of a link between positive affect and improved medication adherence. Better measurement of both affect and medication adherence across chronic conditions is an important focus for future research and will inform targeted interventions to improve adherence and, ultimately, decrease the morbidity, mortality, and cost associated with suboptimal adherence in chronic physical conditions.