Body composition in hemodialysis patients - Is it different from that of normal subjects?

Objective: Body composition assessment is an important method of evaluating nutritional and metabolic status in hemodialysis patients. Patients and methods: To assess the body composition of hemodialysis patients, we used dual-energy X ray absorptiometry to test 40 stable chronic hemodialysis patients and 40 normal subjects. The patients were from 38 to 70 years old, and all without diabetic mellitus. Comparing with the hemodialysis patients, the normal subjects were selected on a one-to-one base with the same sex and about the same age, body weight and height. Results: The lean body mass/body weight (LBM/BW) ratio had no significant statistical difference between hemodialysis patients and normal subjects in this study (63.02 ± 8.42% vs 64.80 ± 7.92%, p =0.3308). The male LBM/BW ratio was higher than that of the female (71.07 ± 4.63% vs 59.30 ± 6.35%, p < 0.0001). According to the multiple linear regression analyses, the LBM of hemodialysis patients had positive correlation with gender (p < 0.0001), height (p = 0.0360) and weight (p < 0.0001). The total bone mineral density (BMD) of hemodialysis patients was found to be lower than that of the normal subjects (0.90 ± 0.10 g/cm vs 0.97 ± 0.08 g/cm, p = 0.0092). The BMD had been found to be low in the hemodialysis patients with serum intact parathyroid hormone (iPTH) > 1700 pg/ml. The BMD had negative correlation with age in the female hemodialysis patients (r = 0.63, p = 0.0009), but no correlation in the male hemodialysis patients and in the female or male normal subjects. With the multiple linear regression analyses, the BMD of hemodialysis patients had positive correlation with weight (p = 0.0329) and negative correlation with age (p = 0.0183) and serum iPTH (p = 0.0231). Conclusion: We concluded that: the LBM/BW ratio of hemodialysis patients was not different from that of normal subjects. Severe secondary hyperparathyroidism hemodialysis patients had low BMD. The BMD had negative correlation with age in the female hemodialysis patients.