A family history of diabetes is related to abnormal insulin sensitivity in African-Caribbean girls of low birth weight: is catch-up weight important?

This retrospective cohort study examined the relationship of birth weight, family history of diabetes (FamHx), and current weight to insulin resistance in Black girls and boys on the Caribbean island of Barbados. A cohort of 56 low birth weight (LBW) and 120 normal birth weight (NBW) adolescents born between January 1, 1986, and December 31, 1988, were recruited for study participation in 2002. FamHx was ascertained by questionnaire. Body mass index (BMI) and waist circumference (WC) were used to assess fat distribution. Fasting blood glucose and insulin were measured from blood samples drawn from each adolescent participant. Insulin resistance was estimated by the homeostasis model assessment (HOMA) technique. These data show that only among LBW girls was a positive (+) FamHx associated with higher HOMA (FamHx "Yes"=1.22 +/- 0.298 vs "No"=0.811 +/- 0.452; P=.032). No significant relationships were observed among boys. Further analyses revealed that compared to their NBW counterparts, LBW girls without FamHx, had a smaller WC (69.70 +/- 9.88cm vs 76.70 +/- 15.64cm, respectively; P=.055). In contrast, LBW girls with a (+) FamHx had similar mean WC (77.71 +/- 16.46cm) to those of NBW girls with (+) FamHx (WC=71.50 +/- 10.38cm; P=.405). These data indicate that along with a family history of diabetes, catch-up weight may be important in assessing diabetes risk in Black Caribbean LBW adolescent girls.

The relationship of internalized racism to body fat distribution and insulin resistance among African adolescent youth.

This study examined the relationship of internalized racism (INR) and hostility to body fat distribution and insulin resistance in black adolescent children age 14-16 years on the Caribbean island of Barbados. Questionnaire data on psychosocial variables and anthropometric measurements, together with a fasting blood sample, were obtained from 53 low-birthweight and 119 normal-birthweight adolescents. Insulin resistance was calculated using the homeostasis model assessment (HOMA). Spearman correlation analyses showed that both INR (r = 0.244) and hostility (r = 0.204) were significantly (p < 0.05) correlated with waist circumference in girls but not boys. Among girls, age- and birthweight-adjusted mean levels of BMI and waist circumference were greater for those with high levels of INR and hostility compared to those with low levels of both variables. In multiple logistic regression analyses, a high INR remained independently associated [odds ratio = 3.30 (95% CI = 1.30-8.36); p = 0.012] with having an elevated HOMA value in models that included age, income, birthweight, hostility, physical activity and family history of diabetes. The results of the current study show that the positive relationship between INR and metabolic health risk seen in African-Caribbean adults also exists in African Caribbean adolescent youth independent of birthweight.