Type 2 diabetes and maternal family history - An impact beyond slow glucose removal rate and fasting hyperglycemia in low-risk individuals? Results from 22.5 years of follow-up of healthy nondiabetic men

OBJECTIVE - Although an excess transmission of type 2 diabetes from mothers has been documented, whether this is an independent trait or whether the e ffect can be detected early through risk factors for type 2 diabetes remain s to be elucidated. The objective of this study was to investigate the prev alence of and the possible prospective effect of family history on type 2 d iabetes incidence adjusted for multiple diabetes risk factors in a 22.5-yea r follow-up study of healthy men. RESEARCH DESIGN IND METHODS - A total of 1,947 apparently healthy nondiabet ic men with fasting blood glucose (FBG) levels <110 mg/dl at baseline, in w hom an intravenous glucose tolerance test (IVGTT) was administered and seve ral conventional risk factors were measured, were followed for 22.5 years. Family history data were obtained at the base line examination, and morbidi ty data were obtained from repeated investigations, hospital records, and d eath certificates. RESULTS - A total of 131 men reported maternal diabetes family history only , 65 men reported paternal diabetes family history only, and 10 men reporte d both maternal and paternal diabetes family history. Among the 1,947 men, 143 cases of type 2 diabetes developed during 22.5 years of observation. Ma ternal family history and combined maternal and paternal family history pre disposed to future type 2 diabetes both in univariate Cox analysis and in m ultivariate Cox regression analysis after adjusting for glucose disappearan ce rate (R-d) during an IVGTT, FBG level, BMI, physical fitness, triglyceri de level, and age Maternal family history showed a relative risk (RR) of 2. 51 (95% CI 1.55-4.07), combined maternal and paternal family history showed an RR of 3.96 (1.22-12.9), and paternal family history showed an RR of 1.4 1 (0.657-3.05) in multivariate analysis. CONCLUSIONS - Maternal family history appears to be an important risk facto r for type 2 diabetes independent of prediabetic R-d, FBG, BMI, and physica l fitness levels.