An evaluation of patients' adherence with hypoglycemic medications among Papua New Guineans with type 2 diabetes: influencing factors

Purpose: The aims of this study were to evaluate the extent of adherence to hypoglycemic medications, assess the relationship between adherence and glycemic control, and evaluate factors affecting adherence. Research design and methods: This was a cross-sectional study of patients with established type 2 diabetes attending the Port Moresby General Hospital Diabetes Clinic. Face-to-face interviews were conducted using a questionnaire designed for the study and data were collected concerning the 3 months prior to interview. The questionnaire covered demographic details, lifestyle, biochemical and physical measurements, and medication management. Glycemic control was investigated among patients adhering to their medications (not missing doses) to different degrees (100%, 95%, 90%, and 80%). Results: Of a total of 356 participants who were prescribed hypoglycemic medications, 59.6% omitted some of their doses. Age appeared to have a significant impact on adherence at some levels of adherence, with those aged >60 years being more likely to be adherent (logistic regression). Those who were 95%-99% and those who were <80% adherent had a statistically significant risk of a high glycated hemoglobin of >10% (85.5 mmol/mol). Multiple factors were identified as contributors to nonadherence, with patient-based issues (86.0%) and the health care system (21.7%) being the most common. Conclusion: This study showed a significant level of nonadherence among patients with type 2 diabetes in Papua New Guinea. Nonadherence to medication appeared to be associated with poor glycemic control and was due to a variety of reasons. Future interventions aimed at improving adherence will need to take these into account.