Abstract: FR-PO417

C-Reactive Protein Mediates the Association between Central Obesity and Microalbuminuria among Persons with the Metabolic Syndrome, Especially in African Americans

Session Information

Category: Chronic Kidney Disease (Non-Dialysis)

  • 301 CKD: Risk Factors for Incidence and Progression

Authors

  • Sinha, Satyesh K., Charles R Drew University of Medicine and Science, Los Angeles, California, United States
  • Shaheen, Magda, Charles R Drew University of Medicine and Science, Los Angeles, California, United States
  • Pan, Deyu, Charles R Drew University of Medicine and Science, Los Angeles, California, United States
  • Norris, Keith C., None, Westchester, California, United States
  • Nicholas, Susanne B., None, Westchester, California, United States
Background

C-reactive protein (CRP), an inflammatory marker, is associated with the metabolic syndrome (MetS) and chronic kidney disease (CKD). However, little is known about the racial disparities of the effect of CRP on the association between individual components of the MetS and microalbuminuria (MA).

Methods

We analyzed National Health and Nutrition Examination Surveys (NHANES) data, (1999-2010) for adults (aged >20 years) with MetS (N=5700). We used multiple logistic regression to assess the independent relationship between MetS components and MA, adjusting for age, gender, race/ethnicity and estimated glomerular filtration rate (eGFR). We used the Sobel-Goodman mediation tests to examine the extent of how CRP influences the effect of MetS components on MA by race/ethnicity. We examined the association between CRP and MA and tested the ability of CRP to reclassify risk using the net reclassification index with and without CRP.

Results

In the multivariate model, CRP, as well as central obesity, blood pressure, fasting plasma glucose, and high-density lipoprotein (HDL), were independent predictors of MA, p<0.05. The mediation test showed that the proportion of total effect of the MetS components on MA, mediated by CRP, is: 0.11 for HDL and 0.40 for central obesity, p<0.05. These levels varied by race/ethnicity. The mediation effect of CRP for central obesity (highest prevalence in African Americans; AAs) was highest for AAs (0.94) compared to Whites (0.55) or Hispanics (0.18), p<0.05The addition of CRP to the adjusted model of MetS components, demographics and eGFR resulted in net reclassification improvement of 0.11 (standard error=0.03, p=0.002) but no significant change in the prediction of MA (receiver-operating characteristics–area under the curve; without CRP=0.66; with CRP=0.67).

Conclusion

We conclude that CRP mediates the association between MA and both HDL and central obesity. Importantly, for AAs, CRP mediates the relationship between MA and central obesity. Grant Support: Supported in part by NIH grants U54-MD-008149, UL1TR000124, P30AG021684, U54MD007598, and S21 MD000103.

Funding

  • Other NIH Support