Objective— To determine whether diabetes risk is influenced by which parent (a parental history of diabetes is a well-documented risk factor for NIDDM) is reported to have diabetes.
Research Design and Methods— We compared the prevalence of NIDDM and IGT for 4914 subjects according to their parental history of diabetes (mother only, father only, both parents, neither parent). Subjects were drawn from the San Antonio Heart Study, a population-based survey of diabetes and cardiovascular risk factors conducted in Mexican American and non-Hispanic white individuals between 1979–1988.
Results— Men with a parental history of diabetes had a higher prevalence of both NIDDM and impaired glucose tolerance than men reporting no parental history of diabetes. Prevalence was equally high regardless of which parent, or whether both parents, had diabetes. In contrast, in women, only a maternal history of diabetes was associated with a higher prevalence of NIDDM and impaired glucose tolerance. Virtually no difference in NIDDM prevalence was found between women with a paternal-only history of diabetes and women with no parental history of diabetes.
Conclusions— Results differed markedly between men and women. The reason for this sex difference is unclear. It may represent a measurement bias, a sex-specific environmental effect, or a genetic effect that is expressed or transmitted differently between the sexes.