Five-Year Glycemic Trajectories Among Healthy African-American and European-American Offspring of Parents With Type 2 Diabetes.

BACKGROUND

Cross-sectional surveys report a higher prevalence of diagnosed type 2 diabetes mellitus (T2DM) in African Americans (AA) than European Americans (EA). We studied 5-year glycemic excursions among AA and EA in the Pathobiology of Prediabetes in A Biracial Cohort study, to assess ethnic disparities.

MATERIALS AND METHODS

Pathobiology of Prediabetes in A Biracial Cohort followed normoglycemic offspring of parents with T2DM for 5 years, with serial assessments of oral glucose tolerance test , anthropometry, body fat, insulin sensitivity and beta-cell function. The primary outcome was progression to prediabetes (impaired fasting glucose and/or impaired glucose tolerance). We further analyzed 5-year changes in fasting (FPG) and 2-hour plasma glucose (2hrPG).

RESULTS

One hundred and one (52 AA, 49 EA) out of 343 subjects developed prediabetes during follow-up. The change in FPG ranged from -24 mg/dl to +38 mg/dl. The FPG remained stable (± 5 mg/dl from baseline) in 50% of EA and 46.8% of AA and the 2hrPG remained stable (± 25 mg/dl from baseline) in 73.7% of EA and 71.0 % of AA during follow-up. The proportions with change in FPG of 5mg/dl to >25 mg/dl and 2hrPG of 25 mg/dl to >50 mg/dl were similar in EA and AA offspring, as were the 10th - 90th percentiles of the distribution of 5-year changes in FPG and 2hrPG.

CONCLUSIONS

During 5 years of follow-up, black and white offspring of parents with T2DM exhibited remarkable phenotypic concordance of glycemic trajectories. Thus, parental history of T2DM may be a stronger factor than race/ethnicity in the prediction of longitudinal glycemic trends.