Patient-reported perceptions of side effects of antihyperglycemic medication and adherence to medication regimens in persons with diabetes mellitus

Background: With recent media attention to drug safety, patients may have heightened concerns about the side effects of medications that may affect their compliance with treatment. Objectives: The purpose of this study was to determine the proportion of patients with type 2 diabetes mellitus who perceived having experienced side effects of antihyperglycemic medications, the proportion of these patients who communicated their concerns to physicians, and the potential association between the perception of experiencing side effects and adherence to medication regimens. Methods: Patients with diabetes were identified through the claims of a Midwest US managed care organization, using Health Plan Employer Data and Information Set criteria. Questionnaires were mailed to randomly selected patients. Patients receiving oral antihyperglycemic medications were selected as prospective subjects. Patients were excluded if they were receiving insulin. Results: The responses of 445 patients meeting the study criteria were collected and analyzed. The subjects were predominately white, with a mean (SD)Age of 56 (11) years and a mean duration of diabetes of 7.3 (8.8) years. One hundred forty-eight (33%) subjects reported a perception of having experienced side effects of antihyperglycemic medication; 126 (85%) subjects reported that they had communicated these concerns to their physicians. Analysis of the subjects' responses indicated an association between the perception of having experienced side effects and non-adherence to antihyperglycemic medication regimens = -0.15; P < 0.010). Conclusions: Nearly one third of subjects with diabetes receiving oral noninsulin antihyperglycemic medications reported a perception of having experienced medication-related side effects. Despite the large portion of subjects who reported that they had communicated these concerns to their physicians, the perception of experiencing medication-related side effects was significantly associated with nonadherence to antihyperglycemic drug regimens.