Medication adherence on quality of life among adults with type 2 diabetes mellitus: an exploratory analysis on the EDDMQoL study

Purpose This study examined the association between medication adherence (MA) and health-related quality of life (HRQoL) among the adult type 2 diabetes mellitus at the primary care level. Methods In this cross-sectional study, the 8-item Morisky Medication Adherence Scale (MMAS) was the main independent variable and the World Health Organization Quality of Life-Brief the dependent variable. Besides socio-demographic data, diabetes-related distress (DRD) and depression (DS) were included as covariates. Independent association between the MMAS score and HRQoL was done using multiple linear regression. Results The participants' response rate was 93.1 % (700/752). Majorities were female (52.8 %), Malay (52.9 %) and married (79.1 %). The mean (SD) for age and the MMAS score was 56.9 (10.18) and 5.6 (1.42), respectively. MMAS total score correlated significantly with all HRQoL domains: overall QoL (OQoL) (r = 0.17), physical QoL (r = 0.11), psychological QoL (r = 0.10), social relationship QoL (r = 0.15) and environmental QoL (EQoL) (r = 0.18). After adjustment for covariates (age, gender, ethnicity, religion, education, income, exercise, macrovascular complications, DRD and DS), MA had persistent effects on OQoL (B = 0.53, 95 % CI 0.012-1.048) and EQoL (B = 0.95, 95 % CI 0.235-1.667). Conclusion MA showed prevalent correlation and positive effects on the domains of HRQoL. Despite the small effects of MA on HRQoL, the sheer presence of the independent effects provides healthcare providers good reason for initiative and intervention to improve MA, which would improve quality of life.