Associations between breast adipose tissue, body fat distribution and cardiometabolic risk in women: cross-sectional data and weight-loss intervention.

BACKGROUND/OBJECTIVES: Recent studies have shown that a high breast volume predicts visceral adipose tissue (VAT) and risk for type 2 diabetes independently of body mass index (BMI) and waist circumference (WC). To investigate the relationships between breast adipose tissue (BrAT), body fat distribution and cardiometabolic risk factors.

SUBJECTS/METHODS: In all, 97 healthy females (age 19-46 years, BMI 16.8-46.8 kg/m2) were examined cross-sectionally. A subgroup of 57 overweight and obese women (BMI 34.7±4.5 kg/m2) was investigated before and after diet-induced weight loss (-8.3±4 kg). Fat mass (FM) was measured by air-displacement plethysmography. Volumes of BrAT, VAT and subcutaneous adipose tissue (SAT) of the trunk and extremeties were assessed by whole-body magnetic resonance imaging (MRI). Cardiometabolic risk was assessed by lipid profile, fasting glucose, insulin, adiponectin and leptin levels.

RESULTS: A high proportion of BrAT was associated with higher truncal and lower leg SAT. Weight loss-induced decline in BrAT as a percentage of total adipose tissue was correlated with decreases in SAT(trunk) and inversely with SAT(legs) and VAT. No relationships were found between BrAT and cardiometabolic risk factors. By contrast, SAT(trunk) and VAT showed positive and SAT(legs) inverse associations with cardiometabolic risk factors in cross-sectional as well as longitudinal analysis. The association between BrAT and VAT was lost after adjusting for %FM and truncal SAT.

CONCLUSIONS: Our results indicate that high BrAT reflects a phenotype with increased SAT(trunk) and low SAT(legs). BrAT showed no independent relationships with VAT and cardiometabolic risk factors.