Significant Positive Association Between Parathyroid Hormone and Fat Mass and Lean Mass in Chronic Hemodialysis Patients

Journal of Clinical Endocrinology and Metabolism

BACKGROUND
It has been reported that there is a significant positive relationship between PTH and body weight or body mass index in the general population. However, little is known about this relationship in dialysis patients in whom PTH levels are higher. It is also not known whether fat mass or lean mass is associated with serum PTH among these patients. In the present study, we examined the association of intact PTH with fat mass and lean mass in hemodialysis patients.

METHODS
Serum intact PTH, calcium, and phosphate were measured in 590 hemodialysis patients (age, 60.2 ± 12.2 y; median hemodialysis duration, 59.6 mo; 343 males and 247 females; diabetics, 27.7%). Fat mass and lean mass were measured by dual-energy x-ray absorptiometry.

RESULTS
Intact PTH correlated significantly and positively with body weight and body mass index in all patients. Intact PTH correlated significantly and positively with fat mass and lean mass in males (P < .01), and tended to correlate positively with fat mass and lean mass in females (P < .1). In multiple regression analyses after adjustment for age, gender, hemodialysis duration, calcium, phosphate, vitamin D use, and phosphate binder use, intact PTH was associated significantly with body weight (ß = .190; P < .0001), body mass index (ß = .177; P < .0001), fat mass (ß = .142; P < .0005), and lean mass (ß = .192; P < .01). Furthermore, intact PTH was associated significantly and independently with both fat mass and lean mass after adjustment (R2 = .206; P < .0001).

CONCLUSIONS
Serum intact PTH in chronic hemodialysis patients is associated significantly and positively with body composition of fat mass and lean mass.