Prehemodialysis care by dietitians and first-year mortality after initiation of hemodialysis

Background: Since January 2002, Medicare has provided payment for medical nutrition therapy for patients with chronic kidney disease. Few patients receive dietary counseling before end-stage renal disease onset; whether such counseling is associated with improved outcomes is unknown. Study Design: Retrospective cohort analysis. Setting & Participants: Patients who initiated hemodialysis therapy on June 1, 2005, to May 31, 2007, in the United States for whom predialysis dietitian care was reported on the Centers for Medicare & Medicaid Services Medical Evidence Report. Predictor: Dietitian care before end-stage renal disease onset. Outcome: Time to death. Measurements: Propensity score for dietitian care calculated using logistic regression; Cox regression analysis used to compare time to death by predialysis dietitian care overall and stratified by tertiles of propensity score, adjusting for baseline characteristics. Results: Most patients (88%) received no dietitian care; 9% received dietitian care for 12 months or less, and 3% received dietitian care for more than 12 months before dialysis therapy initiation (total N = 156,440). Predialysis dietitian care was associated independently with higher albumin and lower total cholesterol levels at dialysis therapy initiation. There was evidence of an independent association between predialysis dietitian care for longer than 12 months and decreased mortality during the first year on dialysis therapy for the second tertile of propensity score. Adjusted mortality HRs were 1.16 (95% CI, 0.44-3.09; P = 0.8), 0.81 (95% CI, 0.71-0.93; P = 0.002), and 0.93 (95% CI, 0.86-1.01; P = 0.1) in the first, second, and third tertiles of propensity score, respectively. Limitations: Information for dietitian care was missing for 18.6% of Medical Evidence Reports and has low sensitivity; including only incident dialysis patients precluded evaluation of an association between dietitian care and chronic kidney disease progression; the observational design allowed the possibility of residual confounding. Conclusions: Our study suggests an independent association between predialysis dietitian care for more than 12 months and lower mortality during the first year on dialysis therapy.