Biochemical Urine Testing of Medication Adherence and Its Association With Clinical Markers in an Outpatient Population of Type 2 Diabetes Patients: Analysis in the DIAbetes and LifEstyle Cohort Twente (DIALECT)
Research Design and Methods: Analyses were performed in baseline data of 457 patients in the DIAbetes and LifEstyle Cohort Twente (DIALECT) study. Adherence to OADs (oral antidiabetics), antihypertensives and statins was determined by analyzing baseline urine samples using LC-MS/MS. Primary outcomes were micro/macrovascular complications and treatment targets of LDL-cholesterol, HbA1c and blood pressure. These were all assessed cross-sectionally at baseline.
Results: Overall, 89.3% of the patients were identified as being adherent. Adherence rates to OADs, antihypertensives and statins were 95.7%, 92.0%, and 95.5%, respectively. The prevalence of microvascular (81.6% vs 66.2%, p = 0.029) and macrovascular complications (55.1% versus 37.0%, p = 0.014) was significantly higher in non-adherent patients. The percentage of patients who reached an LDL-cholesterol target of £2.5 mmol/L was lower (67.4% versus 81.1%, p = 0.029) in non-adherent patients. Binary logistic regression indicated that a higher BMI, current smoking, elevated serum LDL-cholesterol, high HbA1c, the presence of diabetic kidney disease and the presence of macrovascular disease were associated with non-adherence.
Conclusion: Despite medication adherence of real-world type 2 diabetes patients managed in specialist care was relatively high, the prevalence of microvascular and macrovascular complications was significantly higher in non-adherent patients and treatment targets were reached less frequently. This emphasizes the importance of objective detection and tailored interventions to improve non-adherence.