This study investigates factors associated with non-adherence to continuous drug therapy in individuals 40 years and older. A population-based survey was conducted in Cambé, Paraná State, Brazil. Treatment adherence was assessed with the four-item Morisky et al. medication adherence scale. The study also assessed socio-demographic variables and health services access and use of medication. Among 1,180 interviewees, 78% reported use of medication, with continuous use in 55%. The study analyzed 639 individuals, the majority female, ranging from 40 to 59 years of age, with low schooling, and from socioeconomic stratum C (on a scale from A to E). Prevalence of non-adherence was 63.5%. Mean therapeutic complexity was 8.1. After adjusted analysis, the following factors remained associated with non-adherence: not being assisted by community health workers, discontinuous access to medication, and high frequency of medication throughout the day. The results indicate high prevalence of non-adherence, with potentially negative impacts for individuals and society.
Medication Adherence; Pharmacoepidemiology; Therapeutics; Chronic Diseases