Background: Reduction of body mass index (BMI) significantly affects mortality in haemodialysis (HD) patients, but it remains to be determined which of the body components influences mortality.
Methods: We examined the whole body composition of 262 HD patients by dual-energy X-ray absorptiometry (DEXA) (age: 60+/-12 years; HD duration 9+/-7 years; male/female: 177/85; diabetics, n=50) and subsequently followed mortality for 5 years.
Results: Patient age was significantly correlated with limb/trunk lean mass (LTLM) ratio (r=-0.350, P<0.01) and % fat content in whole tissue (r=0.145, P=0.02). There was a significant positive relationship between LTLM ratio and serum creatinine both in males (r=0.404, P<0.01) and females (r=0.267, P=0.01). Diabetic males and females both had a significantly lower LTLM ratio than non-diabetic males (P<0.01) and females (P<0.04). During the 5 years, 65 patients (24.8%) died mainly of cardiovascular diseases and infections. BMI was lower in the expired group than in survivors (P<0.04). LTLM ratio was significantly reduced in the expired group compared with the surviving males (0.629+/-0.097 vs 0.707+/-0.094; P<0.01) and females (0.611+/-0.101 vs 0.651+/-0.078; P<0.01). Cox's proportional hazards analysis revealed that the reduction of LTLM ratio was a significant determinant of death in men (P<0.01), while a lower percentage of fat content of trunk was a significant determinant of death in women (P<0.01). In contrast, BMI did not influence mortality in either sex.
Conclusions: Measurements of regional lean and fat mass volumes by DEXA may be useful for predicting death in patients receiving long-term HD.