High Sensitivity C-Reactive Protein Realted to Chronic Kidney Disease in Asymptomatic Adults: The Bogalusa Heart Study

Background:Low grade systemic inflammation depicted by high sensitivity C-reactive protein (hs-CRP) has emerged as an independent predictor of cardiovascular (CV) disease and type 2 diabetes. However, limited data are available regarding its role in predicting early onset of chronic kidney disease (CKD) which remains asymptomatic until its late stage.  Cystatin C is a low molecule protein that is excreted through kidney and used as a biomarker of CKD. However, information linking hs- CRP to CKD measured by cystatin C in a community-based cohort is scant.

Methods:We examined the cross-sectional study of hs-CRP to cystatin C in a cohort of 583 black and white subjects (26 % black, 41 % male) aged 29-51 years (mean 42.6 years) enrolled in the Bogalusa Heart Study during years of 2007 to 2010. We conducted multivariate regression analysis relating hs-CRP to cystatin C adjusting for CV risk factors.

Results: Blacks vs. whites and females vs. males had significantly higher hs-CRP level (2.70 mg/L vs. 1.90 mg/L, p=0.007 and 2.47 mg/L vs. 1.59 mg/L, p=0.0009 respectively). Blacks vs. whites had no difference of cystatin C levels (0.82 m/L vs. 0.80 mg/L, p =0.82) but males vs. females had higher cystatin C level (0.84 mg/L vs. 0.80 mg/L, P=0.02). There was no evidence of effect modification by race and sex. Therefore, in a multivariate regression model in total sample adjusting for sex, systolic blood pressure and current smoking status, hs-CRP remained independently and positively associated with cystatin C (p=0.0003).

Conclusion: The observed deleterious effect of hs-CRP on cystatin C in asymptomatic adults underscores the utility of hs-CRP as a biomarker of early onset of CKD also.