Adapting and validating diabetes simulation models across settings: Accounting for mortality differences using administrative data

Abstract

AimsTo develop age and sex-specific risk equations for predicting mortality following major complications of diabetes, using a large linked administrative dataset from Western Australia (WA) and to incorporate these into an existing diabetes simulation model. MethodsThe study uses linked hospital and mortality records on 13,884 patients following a major diabetes-related complication with a mean (SD) duration of 2.62 (2.25) years. Risk equations for predicting mortality were derived and integrated into the UKPDS Outcomes Model. Estimates of life expectancy and incremental QALYs gained as a result of two theoretical therapies (a reduction of HbA1c of 1%, and reduction of systolic blood pressure of 10mmHg) were determined using the original and adapted models. ResultsThe two versions of the model generated differences in life expectancy following specific events; however there was little impact of using alternative mortality equations on incremental QALYs gained as a result of reducing HbA1c or systolic blood pressure, or on outcomes of life expectancy for a cohort initially free of complications. ConclusionsMortality following complications varies across diabetic populations and can impact on estimates of life expectancy, but appears to have less impact on incremental benefits of interventions that are commonly used in pharmoeconomic analyses.