Self-management competence as a predictor of outcomes of intensive therapy or usual care in youth with type 1 diabetes

OBJECTIVE - This article evaluates prediction of HbA(1c) during an 18-month randomized trial of intensive therapy (IT) versus usual care (UC) for type I diabetes in 142 youth. RESEARCH DESIGN AND METHODS - Patients received a composite score for self-management competence (SMC) that combined standardized scores on baseline measures of diabetes knowledge, treatment adherence, and quality of health care interactions. They were categorized by tertiles split into low, moderate, and high SMC levels. RESULTS - IT yielded very similar mean HbA(1c) levels in all three SMC groups. However, in UC patients, HbA(1c) increased markedly for low-SMC youth but not for moderate- and high-SMC youth during the trial. Compared with the mean HbA(1c),, of their UC counterparts, low-SMC patients realized greater glycemic benefit from IT than did the moderate- or high-SMC youth. Baseline SMC was more strongly correlated with HbA(1c), for UC than IT. CONCLUSIONS - All three SMC groups realized similar glycemic benefits from IT. The mean HbA(1c) levels of low-SMC patients in the UC group increased markedly over 18 months, whereas HbA(1c) levels of low-SMC patients in the IT group did not differ significantly from that of moderate- and high-SMC patients. Relative to their UC counterparts, low-SMC patients derived greater glycemic benefit from IT than did moderate- or high-SMC youth. SMC may be more critical to the success of UC than IT. Perhaps more importantly, patients should not be denied access to IT on the basis of limited competence in diabetes self-management.