Medication non-adherence in patients with type 2 diabetes mellitus with full access to medicines

The pharmacological treatment for Type 2 diabetes mellitus (T2DM) is continuous and adherence to medication is critical for disease control. Restricted access to medicines is one of the most important barriers to adherence to T2DM treatment. This study aimed to evaluate other factors for medication non-adherence by studying patients with full access to oral hypoglycemic agents.

Cross-sectional study with 300 patients receiving their medication without costs from a referral center for diabetes care in Crato, Ceará (Brazil). Participants were recruited from January to December 2017. Information was obtained by self-applied questionnaires, and the drugs used were confirmed in the prescription. Adherence to medication was determined by the Morisky Medication Adherence Scale (MMAS-4). Patient perceptions of drugs were assessed by the Beliefs about Medicines Questionnaire (BMQ).

Only 22.7% of participants met the criterion of high adherence to medication. The most frequent characteristics in the low adherence group were married; hypertension; no regular physical activity; therapy based on the combination of two or more oral antidiabetic agents without insulin; low score in the BMQ necessity scale. Necessity score in BMQ increased with age and the number of medications used and decreased if the patient had family members with the same disease and had children.

Full access to medicines did not assure high adherence to pharmacological treatment of type 2 diabetes mellitus. Distinctive factors to medication non-adherence may be found and specific barriers should be considered when planning actions for improving adherence in such populations.