Purpose: Parathyroid hormone (PTH) has been shown to correlate positively with fat mass, however there are no studies that have investigated whether this association is a result of, or is modified by, body fat distribution. The aim of this study was to investigate the association of PTH with several body composition indices, namely visceral (VAT) and subcutaneous adiposity (SCAT) as well as with lean mass and with serum leptin, which has been reported to increase PTH.
Methods: This was a cross-sectional study in which PTH was measured by chemiluminescent assay; body fat and lean mass by dual-energy X-ray absorptiometry (DXA) and abdominal fat by ultrasonography in 714 healthy adults aged 18-65 years. Serum leptin was measured by ELISA.
Results: In a multivariate linear regression model that included height, age, gender, ethnicity, serum 25 hydroxyvitamin D, leptin levels, calcium, magnesium and phosphate concentrations, glomerular filtration rate, smoking status, and calcium and vitamin D supplementation as independent variables and PTH as the dependent variable, VAT (β = 0.094, p = 0.035) correlated significantly with PTH levels but SCAT (β = -0.045, p = 0.386) and body fat mass (β = 0.098, p = 0.126) did not. Leptin did not correlate with PTH (β = 0.013, p = 0.832) in this regression model.
Conclusions: Plasma PTH is significantly associated with VAT in healthy adults. In view of the association of PTH with increased cardiovascular mortality, it is important to investigate this association further.
Keywords: Body fat; Parathyroid hormone; Visceral fat.