Participation in a Structured Weight Loss Program and All-Cause Mortality and Cardiovascular Morbidity in Obese Patients With Chronic Kidney Disease.

ABSTRACT

OBJECTIVE: To determine if participation in a weight loss program impacted upon a composite end point of all-cause mortality and cardiovascular morbidity in obese patients with chronic kidney disease (CKD). DESIGN: Retrospective cohort study. SUBJECTS: All patients with a body mass index (BMI) >30 kg/m(2) or >28 kg/m(2) with at least 1 comorbidity (hypertension, diabetes, or dyslipidemia) referred to an established weight management program (WMP) from 2005 to 2009 at a metropolitan tertiary teaching hospital were eligible for inclusion in the study cohort. INTERVENTION Twelve-month structured weight loss program. MAIN OUTCOME MEASURES: Combined outcome of all-cause mortality, myocardial infarction, stroke, and hospitalization for congestive heart failure; kidney transplantation waitlisting. RESULTS: A total of 169 obese patients with CKD commenced the WMP and 169 did not-becoming the observational control group (CON). There were no significant differences between groups for age, BMI, sex, ethnicity, smoking, hypertension, or kidney function at baseline, although CON included more patients with diabetes than WMP (49% vs. 38%, P = .03). Kaplan-Meier survival analysis with log-rank test differed between groups for the combined outcome (P = .03). Cox regression analysis with adjustment for age, sex, ethnicity, hypertension, diabetes, kidney function, baseline BMI, and smoking status, indicated that patients in WMP had a significantly longer event-free period for the combined outcome, than those in CON (adjusted hazard ratio 0.53; 95% confidence interval [CI] 0.29-0.97; P = .04). Participation in the WMP did not increase the likelihood of kidney transplantation waitlisting (odds ratio [OR] 1.06; 95% CI 0.39-2.87; P = .9). Lower baseline BMI and greater weight loss over 12 months were the only factors related to kidney transplantation waitlisting (adjusted R(2) = 0.426). CONCLUSIONS: Participation in a structured weight loss program may be associated with improved outcomes in obese patients with CKD.