Association of obesity with inflammation in chronic kidney disease: a cross-sectional study.

ABSTRACT

OBJECTIVE: As adipose tissue releases inflammatory cytokines, obesity is associated with elevated C-reactive protein (CRP) levels in the general population. We examined the cross-sectional association of body mass index (BMI) with CRP in patients with chronic kidney disease (CKD). DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: Ninety-four CKD patients with varying levels of renal function seen at the University of Utah outpatient renal clinic were studied. METHODS: Data on demographics (age, gender, race), comorbidity (diabetes mellitus, hypertension, myocardial infarction/angina, cerebrovascular disease, peripheral vascular disease, and smoking) and anthropometry (height and weight) were obtained by patient interview and chart reviews. High-sensitivity CRP was measured by the N-latex assay on a BN II nephelometer. MAIN OUTCOME MEASURE: Risk factors of high CRP. RESULTS: In a multivariable logistic regression model, when compared with patients with a BMI < 25, the odds of CRP > 3.0 mg/L were 2.5-fold (95% CI, 1.02 to 5.99) higher in patients with BMI > or = 30. In a stepwise multiple linear regression model, BMI (regression coefficient [beta] = 0.06; 95% CI, 0.03 to 0.1; P < .01), serum creatinine (beta = 0.16; 95% CI, 0.04 to 0.3; P = .01) and age (beta = 0.01; 95% CI, -0.001 to 0.03; P = .05) were significantly associated with log transformed CRP. CONCLUSION: These data suggest that as in the general population, in CKD patients, obesity, a traditional risk factor for atherosclerosis, is associated with inflammation, a novel risk factor for atherosclerosis.