Differences in health outcomes associated with initial adherence to oral antidiabetes medications among veterans with uncomplicated Type 2 diabetes: a 5‐year survival analysis

• Published in: Diabetic medicine Vol. 35; no. 11; pp. 1571 - 1579
• Main Authors: Gatwood, J. D., Chisholm‐Burns, M., Davis, R., Thomas, F., Potukuchi, P., Hung, A., Kovesdy, C. P.
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01.11.2018
• Subjects: Administration, Oral; Adult; Aged; Aged, 80 and over; Antidiabetics; Cerebral infarction; Diabetes; Diabetes mellitus; Diabetes mellitus (non-insulin dependent); Diabetes Mellitus, Type 2 - drug therapy; Diabetes Mellitus, Type 2 - epidemiology; Diabetes Mellitus, Type 2 - mortality; Female; Health risk assessment; Humans; Hypoglycemic Agents - administration & dosage; Insulin; Male; Medication Adherence - statistics & numerical data; Microvasculature; Middle Aged; Myocardial infarction; Retrospective Studies; Stroke; Survival Analysis; Treatment Outcome; Veterans; Veterans - statistics & numerical data
• ISSN: 0742-3071; 1464-5491
• DOI: 10.1111/dme.13775

Aim To determine the association of adherence to oral antidiabetes medication with macrovascular and microvascular complications, time to insulin therapy, revascularization, admissions, and death among veterans with uncomplicated diabetes. Methods This was a retrospective cohort study using the Veterans Affairs Corporate Data Warehouse to examine 159 032 veterans diagnosed with uncomplicated diabetes during 2002–2014 and starting oral antidiabetes therapy for the first time. The first uncomplicated diabetes diagnosis was identified and confirmed by subsequent oral antidiabetes therapy initiation. Adherence was calculated from outpatient pharmacy records using the proportion of days covered over the first year of therapy. Health outcomes were observed up to 5 years beyond the first oral antidiabetes agent fill, and compared according to adherence status using Cox proportional hazards models adjusted for baseline demographic and clinical characteristics. Results During the first 5 years of oral antidiabetes treatment, people initially non‐adherent to oral antidiabetes therapy were more likely to experience myocardial infarction (hazard ratio 1.14, 95% CI 1.03–1.27) and ischaemic stroke (hazard ratio 1.22, 95% CI 1.05–0.1.42), or to die (hazard ratio 1.21; 95% CI 1.15–1.28). Veterans with <20% adherence to oral antidiabetes therapy in the first year had particularly high hazards for ischaemic stroke (hazard ratio 1.78, 95% CI 1.27–2.49) and all‐cause death (hazard ratio 1.33, 95% CI 1.17–151). Adherent people were more likely to be diagnosed with a microvascular complication or chronic kidney disease. Conclusions People who are non‐adherent to treatment were more likely to experience detrimental health outcomes within the first 5 years of antidiabetes therapy. Adherence is paramount to disease management and this should be stressed from the time at which treatment is initiated. What's new? Medication use is suboptimal in people with diabetes and contributes to poorer health outcomes; however, there has been limited research investigating the extent to which early non‐adherence is predictive of detrimental outcomes beyond the initial years of treatment. The present analysis of US veterans with Type 2 diabetes showed that non‐adherence to oral antidiabetes in the first year of treatment can increase the hazard for certain detrimental health outcomes within the subsequent 5 years of therapy. It is essential to convey the importance of adherence to prescribed therapy from the time of initiating antidiabetes therapy, in order to improve the odds of long‐term, adequate disease management