Malnutrition is a relevant risk factor for mortality for patients on maintenance
hemodialysis treatment. In a retrospective study including 377 patients who began
hemodialysis treatment between 1986 and 2001, we assessed the prevalence of different statuses of nutrition and the impact of the initial status of nutrition on the change in
body weight and patient survival. We found an inverse relationship between body mass index (BMI, kg/m2) and the gain in
body weight and BMI within 12 months of
hemodialysis treatment. Underweight and normal weight patients had a substantial increase in these parameters, greatest in underweight subjects, whereas
overweight and obese patients showed only a moderate increase or none (P =.0019, P =.00036). Adjusted mortality rates showed an inverse correlation with the initial BMI (P <.0001). There was a statistically significant difference in the mortality between patients with normal weight and
overweight or
obesity, respectively, showing a more favorable prognosis in
overweight and obese patients (P =.0007; P =.022; log-rank, normal versus
overweight, P =.012).
Weight loss was the greatest independent risk factor for mortality in general. Adjusted hazard ratio of death was highest in underweight patients (3.999; CI, 2.708 to 5.905; P <.0001) and decreased to 2.251 (CI, 1.795 to 2.822; P <.0001) in normal weight, 1.927 (CI, 1.390 to 2.670; P <.0001) in
overweight, and 1.651 (CI, 0.841 to 3.236;
P =.1439) in obese subjects when patients with
weight loss were compared with patients who preserved their initial weight or gained weight. Overall, the initial BMI has an influence on the change in
body weight as well as on patient survival in general and in the case of
weight loss in particular.