Psychosocial and clinical determinants of medication adherence among elderly chronic disease patients in China

Identifying psychosocial factors associated with medication adherence is critical to optimize chronic disease management in elderly patients. This study aimed to explore key psychosocial and clinical determinants of medication adherence and their synergistic interactions among home-dwelling elderly patients with chronic diseases.

A cross-sectional study was conducted among 952 elderly patients. Data were collected using validated scales including Adherence to Refills and Medications Scale (ARMS), Self-efficacy for Appropriate Medication Use Scale (SEAMS), Social Support Rate Scale (SSRS), Beliefs about Medical Questionnaire (BMQ), and The Adapted Chinese medication literacy measure (ChMLM). Univariate and multivariable logistic regression, together with interaction analysis, were used to explore associated factors and their synergistic effects.

Among 952 participants (mean age 70.32 ± 6.95 years, 51.47% male), multivariable analysis showed that living with a caregiver (OR = 6.91, 95% CI: 2.79-17.70, p < 0.001), higher self-efficacy (OR = 1.13, 95% CI: 1.10-1.17, p < 0.001), Support utilization (OR = 1.09, 95% CI: 1.01-1.17, p = 0.027), stronger medication necessity beliefs (OR = 1.06, 95% CI: 1.02-1.11, p = 0.005), and better medication proficiency (OR = 1.02, 95% CI: 1.00-1.04, p = 0.018) were independently associated with good adherence. Conversely, higher medication concerns (OR = 0.94, 95% CI: 0.91-0.98, p = 0.003), Objective support (OR = 0.91, 95% CI: 0.84-0.98, p = 0.020) and more medication knowledge (OR = 0.97, 95% CI: 0.96-0.99, p < 0.001) were associated with poorer adherence. Critically, Six significant synergistic interactions were identified, including Necessity × Concerns and Knowledge × Self-efficacy, suggesting mutual modification between these factors.

Medication adherence is influenced by a complex network of determinants, where cognitive, behavioral, and social factors do not operate in isolation but interact synergistically. Multidimensional interventions targeting high-risk combinations, such as high medication knowledge with low self-efficacy, may effectively improve adherence.