Family history and prevalence of diabetes in the U.S. population: the 6-year results from the National Health and Nutrition Examination Survey (1999-2004).

OBJECTIVE We sought to test the association between stratified levels of familial risk of diabetes and the prevalence of the disease in the U.S. population. RESEARCH DESIGN AND METHODS This study includes 16,388 adults interviewed for the National Health and Nutrition Examination Survey between 1999 and 2004. Fasting glucose was available for a subsample of 6,004 participants. Familial risk of diabetes was classified as average, moderate, or high. The prevalence and the odds of having diabetes were estimated for each risk class after accounting for other risk factors. RESULTS Overall, 69.8% of the U.S. adults were in the average, 22.7% in the moderate, and 7.5% in the high familial risk for diabetes. The crude prevalence of diabetes for each risk class was 5.9, 14.8, and 30%, respectively. The graded association between familial risk and prevalence of diabetes remained even after accounting for sex, race/ethnicity, age, BMI, hypertension, income, and education. Versus people in the average risk class, independently of other risk factors considered, the odds of having diabetes for people in the moderate and high familial risk categories were, respectively, 2.3 and 5.5 times higher. CONCLUSIONS In the U.S. population, family history of diabetes has a significant, independent, and graded association with the prevalence of diabetes. This association not only highlights the importance of shared genes and environment in diabetes but also opens the possibility of formally adding family history to public health strategies aimed at detecting and preventing the disease.