Longitudinal Changes in Body Fat and Its Distribution in Relation to Cardiometabolic Risk in Black South African Women.

BACKGROUND

Ethnic differences in body composition and cardiometabolic risk have been reported in cross-sectional studies. This study aimed to investigate changes in body composition over 5.5 years, and its association with cardiometabolic risk in premenopausal black South African (SA) women.

METHODS

Changes in body composition and body fat distribution (dual-energy x-ray absorptiometry and computerized tomography), fasting glucose, insulin, and lipid concentrations, were measured in 63 black SA women at baseline (age: 27 ± 8 years), and 5.5 years later.

RESULTS

Body weight and fat mass (FM) increased by 6.9 ± 9.9 kg and 4.3 ± 6.9 kg, respectively, over the 5.5 years with a relative (%FM) increase in central and decrease in peripheral FM (all P < 0.05). Fasting glucose and lipid concentrations (except HDL-cholesterol) increased over the follow-up period (all P < 0.05). Both baseline and changes in body fat distribution were associated with cardiometabolic risk. Independent of baseline age, FM and insulin sensitivity, baseline trunk:leg was associated with reduced insulin sensitivity at follow-up (Matsuda index; β = -0.41, P = 0.002). Increasing trunk:gynoid ratio was associated with higher plasma insulin levels (β = 0.31, P = 0.023) and reduced insulin sensitivity (Matsuda index; β = -0.52, P < 0.001) at follow-up.

CONCLUSIONS

Weight gain in free-living black SA women over 5.5 years was associated with a centralization of fat mass, which predicted an increase in cardiometabolic risk.