Kidney Disease Outcomes Quality Initiative (K/DOQI) and the Dialysis Outcomes and Practice Patterns Study (DOPPS): Nutrition guidelines, indicators, and practices

Background: Nutritional markers are important predictors of morbidity and mortality in dialysis patients. The Clinical Practice Guidelines for Nutrition in Chronic Renal Failure provides guidelines for assessing nutritional status that were evaluated using data from the Dialysis Outcomes and Practice Patterns Study (DOPPS). Methods: The level of various nutritional markers (serum albumin, modified subjective global assessment, serum creatinine, normalized protein catabolic rate [nPCR], and body mass index) were described for representative samples of patients and facilities from 7 countries (France, Germany, Italy, Spain, Japan, United Kingdom, and United States) participating in the DOPPS. Results: A strong inverse association was observed between mortality and serum albumin, with a mortality risk 1.38 times higher for patients with serum albumin concentration less than 3.5 g/dL (35 g/L). There were significant differences by country in the proportion of moderately and severely malnourished patients as determined by the modified subjective global assessment score. In the US sample, severely and moderately malnourished patients had a higher mortality risk compared with those not malnourished, 33% and 5% higher, respectively. An inverse relationship exists between serum creatinine concentration and mortality, with a mortality risk 60% to 70% higher in the lowest quartile group compared with the highest quartile group in Europe and the United States. Levels of nPCR varied significantly between European countries, and there was no association between mortality and nPCR in US data. After adjustment for demographic and comorbidity factors, the mortality risk decreased as body mass index increased in both US and European samples. Conclusion: DOPPS data highlight the importance of routine assessment of nutritional status, using multiple parameters, in clinical practice to improve patient care.