DP: Oral antihyperglycemic medication nonadherence and subsequent hospitalization among individuals with type 2 diabetes. Diabetes Care 2004

OBJECTIVE — This study examines the association between oral antihyperglycemic medi-cation nonadherence and subsequent hospitalization among individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS — Using administrative claims data (2000– 2001) from a managed care organization in the Midwestern U.S., this study analyzed 900 enrollees, aged 18 years and over, with type 2 diabetes who were taking oral antihyperglycemic agents both years but who did not use insulin. Nonadherence was defined as a medication possession ratio (MPR) 80%. Multivariate logistic regression analyses were performed where hospitalization in 2001 was regressed on nonadherence to the oral antihyperglycemic drug regimen in 2000, while controlling for nonadherence to drugs for hypertension and dyslipidemia and for hospitalization in 2000, age, sex, intensity of the diabetes drug regimen, and comorbidi-ties. RESULTS — The proportion of enrollees who were nonadherent to the antihyperglycemic drug regimen in 2001 was 28.9%, whereas 18.8 and 26.9 % were nonadherent to antihyperten-sive and lipid-modifying drugs, respectively. The increase in the hospitalization rate for 2001 was most apparent where the antihyperglycemic MPR for 2000 dropped to 80%. Enrollee