Estimation of the impact of diabetes-related complications on health utilities for patients with type 2 diabetes in Ontario, Canada

The goal of this study was to analyze health-related quality of life (HRQL) data from a Canadian population with type 2 diabetes in order to estimate the disutility associated with experiencing a diabetes-related complication. The EQ-5D, a standardized instrument for use as a measure of health outcome, was administered to 1,147 patients in Hamilton, Ontario, with type 2 diabetes. After controlling for age, gender, and duration of diabetes, changes in utility values were estimated by regressing the EQ-5D scores onto binary indicators for the presence of an event. The primary method of analysis was Ordinary Least Squares (OLS) and due to concerns over non-Normality, bootstrap standard errors (SE) were calculated. The analysis included 1,143 participants. Based on the OLS model, reductions in HRQL were associated with duration of diabetes (-0.0015, SE = 0.0006), experiencing a myocardial infarction (MI) (-0.059, SE = 0.017), amputation (-0.063, SE = 0.059), stroke (-0.046, SE = 0.023), and kidney failure (-0.102, SE = 0.047). This study estimated the reductions in HRQL associated with several important complications commonly experienced in patients with diabetes. The greatest impacts on HRQL were associated with kidney failure and MI. The utility values calculated here can be used to assess the outcome of interventions that reduce these diabetes-related complications and will have a useful impact on future economic evaluations of diabetes management strategies in Canada.