Overweight and obesity as a nutritional issue in the dialysis population.

Sir, The European nutritional consensus paper [1] was in general a cogent summary of the major issues currently facing the dialysis population. However, as with other nutritional guidelines [2], it neglects to address the growing threat of overweight and obesity, a problem associated with increased risk of sudden death, coronary artery disease, hypertension, diabetes and dyslipidaemia. The major nutritional illness facing dialysis patients has historically been protein-energy malnutrition. However, in parallel with the burgeoning prevalence of overweight and obesity in the West, there is now clear evidence that overweight and obesity is making inroads in the dialysis population. National data reveal the mean body mass index (BMI) for incident dialysis patients [3], as well as dialysis patients at the time of kidney transplantation [4], to be in the overweight range (BMI 25–29.9), with the trend increasing annually. This should not be surprising as the demographic groups at greatest risk for progression of renal disease and renal failure (i.e. ethnic minorities, the elderly and diabetic patients) are also those most susceptible to overweight and obesity. Concern over this issue may have been mitigated by studies suggesting that a higher BMI in dialysis patients is relatively protective with regards to mortality [5]. However, these reports are vulnerable to confounding by comorbid conditions, by failing to eliminate early mortality from the analyses, and by inappropriately controlling for intermediate risk factors through which overweight and obesity exert their pernicious effects. In contrast, data from the general as well as incident kidney transplant population find that a higher BMI is associated with worse outcomes [4]. It is now time for the nephrology community to approach the issue of overweight and obesity in the dialysis population in a more serious and public manner.