Medication beliefs, treatment complexity, and non-adherence to different drug classes in patients with type 2 diabetes

AbstractObjective ess the relationship of patientsʹ medication beliefs and treatment complexity with unintentional and intentional non-adherence for three therapeutic groups commonly used by patients with type 2 diabetes. s data about adherence (Medication Adherence Report Scale) and beliefs about medicines (Beliefs about Medicines Questionnaire) were combined with prescription data from the Groningen Initiative to ANalyse Type 2 diabetes Treatment (GIANTT) database. Patients were classified as being adherent, mainly unintentional non-adherent, or partly intentional non-adherent per therapeutic group (glucose-, blood pressure-, and lipid-lowering drugs). Treatment complexity was measured using the Medication Regimen Complexity Index, which includes the dosage form, dosing frequency and additional directions of taking the drug. Analyses were performed using Kruskal–Wallis and Mann–Whitney U-tests. s contacted patients, 133 (52%) returned the questionnaire. The patients had a mean age of 66 years and 50% were females. Necessity beliefs were not significantly different between the adherers, mainly unintentional non-adherers, and partly intentional non-adherers (differences smaller than 5 points on a scale from 5 to 25). For blood pressure-lowering drugs, patients reporting intentional non-adherence had higher concern beliefs than adherers (8 point difference, P = 0.01). Treatment complexity scores were lower for adherers but similar for mainly unintentional and partly intentional non-adherers to glucose- and blood pressure-lowering drugs. sion ent complexity was related to non-adherence in general. Beliefs about necessity were not strongly associated with non-adherence, while patientsʹ concern beliefs may be associated with intentional non-adherence. However, the role of these determinants differs per therapeutic group.