The Prescription and Safety of Oral Antidiabetic Drugs in Outpatients with Type 2 Diabetes Mellitus: An Observational, Retrospective, Multicenter Study on the Role of Adherence in a Real-Life Primary Care Setting

Abstract

Introduction: Type 2 diabetes mellitus (T2DM) is a common disease burdened with significant morbidity and mortality. Despite the substantial number of new available drug treatments, adherence to therapy and adverse drug reactions (ADRs) are the major constraint in the management of this disease. We evaluated the use, the adherence, and the safety of antidiabetic drugs in patients with T2DM. Methods: We performed an observational, retrospective, multicenter study on medical records of outpatients referred to general practitioners in Catanzaro (Calabria, Italy). Drug adherence was measured considering the packages of antidiabetic drugs prescribed at the time of admission, after three months, and 1 year later. ADRs were evaluated using the Naranjo probability scale. Collected data were analyzed using the Statistical Package for the Social Sciences. Results: During the study, we evaluated 12,170 medical records of seven general practitioners. The most prescribed drug was metformin alone (28.4%) or with other oral antidiabetics (19.6%) and then insulin (n: 354; men 190, women 164). Logistic regression showed an association between T2DM less than or equal to 5 years and low adherence (p = 0.023). During the study, we recorded 26 ADRs that were correlated with sex (women) and insulin treatment. Conclusions: this real-life study shows that patients with T2DM have a high adherence, probably related to their having a low number of ADRs.