Aim/hypothesis: Chronic renal failure maintenance hemodialysis (HD) patients are at risk for low bone mineral density (BMD) and fractures. Parathyroid hormone (iPTH) plays a pivotal role in the pathophysiology of uremic bone disease, but in healthy population body weight and particularly body composition are more important determinants of bone mass.
Patients and methods: We studied BMD (results were recorded as g/cm2) and T score using DEXA osteometer (DTX-200 Osteometer) on forearm in 42 patients (19 females, 15 post-menopausal and 23 males), who had been on HD for a mean of 42.3±23.2 months. Body composition was evaluated by bioelectrical impedance analysis and quantifies body fat, lean body mass and total body water (FAT%; LBM%; TBW%) using a TBF-110 Body Fat Analyser (Tanita).
Results: The prevalence of osteoporosis was high (84%) in women, and we found significant negative correlation between BMD and age and positive correlation with LBM%. In the multiple regression analysis LBM% was most significant, independent predictor of BMD in women (β coefficient=1.047, P=0.001). The prevalence of osteoporosis was also high (76%) in men, and besides negative correlation between BMD and age we found positive correlation between bone mass and iPTH, as well as with LBM%. In the multiple regression analysis, only iPTH independently predicted BMD in men (β coefficient=0.812, P=0.02).
We conclude that the lean body mass compartment is the most important component of body composition that determines BMD, particularly in post-menopausal HD women. This study suggests also that secondary hyperparathyroidism, confirmed in our group of patients, seems to be independent predictor of bone mass in HD men.
25 - 29 Apr 2009
European Society of Endocrinology