Psychological determinants of medication adherence in patients with hypertension: a systematic review and meta‑analysis

Pharmacological treatment is essential for achieving blood pressure control in patients with hypertension; however, medication adherence remains suboptimal. Understanding its determinants is essential, but the role of psychological factors in medication adherence among hypertensive patients is still unclear. This study aimed to identify and synthesize evidence on modifiable psychological determinants associated with medication adherence in hypertensive patients. A comprehensive search was conducted across multiple databases, including Web of Science, PubMed, EMBASE, CINAHL, and PsycARTICLES, up to September 1, 2025. A random-effects model was used to estimate pooled effect sizes with 95% confidence intervals. A total of 5,455 records were initially retrieved, of which 112 studies met the inclusion criteria. Fifty-one studies were eligible for meta-analysis. The findings identified depressive symptoms (OR = 0.86, 95%CI 0.77 to 0.95, I² = 60.6%) and self-efficacy (OR = 1.60, 95% CI 1.15 to 2.23, I²=93.9%) as the most strongly associated modifiable determinants of medication adherence, with findings supported by sensitivity analyses. Illness perception (β = 0.23, 95% CI 0.13 to 0.32, I²=68.8%), and self-regulation (β = 0.34, 95% CI: 0.23 to 0.44, I²=92.9%) were also associated with adherence; however, these associations should be interpreted cautiously due to substantial heterogeneity and limited robustness across analyses. This study identified several modifiable psychological factors related to medication adherence in patients with hypertension, while highlighting considerable variability across studies. Future research should aim to elucidate the mechanisms by which these psychological determinants impact medication adherence and develop targeted interventions to improve treatment uptake and blood pressure control.