Objective: Studies were performed to investigate the association of the body mass index (BMI) with long-term survival of non-diabetic hemodialysis patients who were monitored for up to 12 years.
Methods: In 116 patients having undergone hemodialysis in 1984, a Kaplan-Meier survival analysis was performed, and a proportional hazard model was applied to calculate the relative risk of mortality in body mass index quintiles.
Results: Those patients with BMI of less than 16.9 kg/m2 and more than 23.0 kg/m2 showed lowered survival relative to the patients with BMI of 17.0-18.9 kg/m2. A proportional hazard model revealed that the patients with BMI of less than 16.9 kg/m2 had the highest risk of mortality independent of age, gender, smoking, duration of hemodialysis, serum albumin, blood pressure and urea reduction rate. Those patients with BMI of over 19.0 kg/m2 also had a high risk of mortality which was progressively elevated with increasing BMI. This higher risk of mortality in those patients with high BMI was associated with such atherosclerotic risk factors as low HDL-cholesterol and high total-/HDL-cholesterol ratio. The number of hospitalizations showed a similar trend to mortality in the body mass index quintiles. The survivors lost their body weight slightly but significantly for 12 years, although there were no significant changes in serum albumin and creatinine. Serum albumin, prealbumin and IGF-1 were within normal range in 1996, suggesting that the survivors did not exhibit severe malnutrition.
Conclusions: These results suggest that long-term survival could be attained by patients with relatively low BMI who have no serious nutritional problems. Nutritional intervention might be required in the overweight patients, in addition to extremely lean patients.