Associations between skeletal muscle mass and elevated blood pressure are independent of body fat: a cross-sectional study in young adult women of African ancestry

Although research on the relationship between lean body mass and blood pressure (BP) has been inconsistent, most studies reported that measures of lean body mass are associated with a higher risk of hypertension. We explored relationships between body composition (fat and skeletal muscle mass) and BP in 1162 young adult African women. Dual-energy X-ray absorptiometry-derived measures of whole-body, central and arm fat mass were associated with higher systolic and diastolic BP, while leg fat percentage was associated with lower systolic and diastolic BP. However, only the associations with diastolic BP remained after adjusting for appendicular skeletal muscle mass (ASM). ASM was associated with higher systolic and diastolic BP, before and after adjusting for whole-body fat percentage and visceral adipose tissue. While there was no overlap in targeted proteomics of BP and body composition, REN was lower in the elevated BP than the normal BP group and was inversely associated with diastolic BP (false rate discovery adjusted P< 0·050). Several proteins were positively associated with both visceral adipose tissue and ASM (LEP, FABP4, IL6 and GGH) and negatively associated with both visceral adipose tissue and ASM (ACAN, CELA3A, PLA2G1B and NCAM1). NOTCH3, ART3, COL1A1, DKK3, ENG, NPTXR, AMY2B and CNTN1 were associated with lower visceral adipose tissue only, and IGFBP1 was associated with lower ASM only. While the associations between body fat and BP were not independent of skeletal muscle mass, the associations between muscle mass and BP were independent of overall and central adiposity in young adult African women. Future interventions targeting muscle mass should also monitor BP in this population.