Selected Risk Factors' Contribution to State-Level Incidence of DiagnosedDiabetes, 2005-2007

Introduction: Differences in incidence of diabetes and prevalence of risk factors for diabetes exist among states. It is unknown how much of this variability in incidence of diagnosed diabetes is due to variability in risk factor prevalence. We investigate the contribution of selected risk factors to state level incidence of diagnosed diabetes. Materials and Methods: Using 2005-2007 data from the Behavioral Risk Factor Surveillance System, we conducted two logistic regressions, both with incident case status as dependent variable. One model considered only state of residence as an independent variable. The other added: age; sex; race/ethnicity; education; inactive lifestyle; and obesity. We compared adjusted and unadjusted odds of incident diabetes among states, and calculated excess risk. Results: Adjusted and unadjusted odds of incident diabetes were similar. Sensitivity analyses showed that this differed little if we used data from earlier years or if we included income or insurance as a risk factor. In most states, the excess risk associated with risk factors was less than 30%. Discussion: Factors other than age, sex, race/ethnicity, education, inactivity, and obesity (i.e., established risk factors for diabetes) might substantially influence the differences in state incidence rates. These factors' identities are unknown. If these factors are identified and modifiable, states might use them to reduce between-state disparities in diabetes incidence.