Association between nonalcoholic liver disease and chronic kidney disease: an ultrasound analysis from NHANES 1988-1994

Abstract

Background/aims: Nonalcoholic fatty liver disease (NAFLD) has been proposed to contribute to chronic kidney disease (CKD) independently of traditional cardiometabolic risk factors. We hypothesized that NAFLD is associated with CKD and that greater severity of NAFLD is associated with higher odds of CKD.

Methods: A cross-sectional analysis of 11,469 adults who participated in the National Health and Nutrition Examination Survey (NHANES) 1988-1994. NAFLD was defined by ultrasonographic detection of steatosis in the absence of other liver diseases. CKD was defined as an estimated glomerular filtration rate of ≤60 ml/min/1.73 m(2) or the presence of albuminuria in subjects with an estimated glomerular filtration rate of >60 ml/min/1.73 m(2).

Results: 2,891 (25.4%) patients in the cohort had CKD. The prevalence of NAFLD was higher in individuals with CKD compared to those without CKD (42.2 vs. 34.5%, p < 0.0001). NAFLD was associated with CKD in unadjusted logistic regression analysis (OR = 1.47, 95% CI: 1.29-1.67, p < 0.0001). Adjustment for demographics and components of metabolic syndrome attenuated this relationship (OR = 1.04, 95% CI: 0.88-1.23, p = 0.64). Moderate and severe NAFLD on ultrasound were increasingly associated with prevalent CKD in unadjusted analysis, but not after adjustment for metabolic syndrome components.

Conclusion: After adjusting for features of metabolic syndrome, ultrasound-diagnosed NAFLD is not associated with prevalent CKD among US adults. Aggressive public health efforts are needed to prevent and treat metabolic syndrome.

Figure 1. Study population

Of the initial 14,797 eligible candidates for the study, a total of 11,469 subjects met inclusion and exclusion criteria and were included in analysis.

Figure 2. Odds of prevalent CKD in patients with different ultrasonographic severity of NAFLD as compared to patients without NAFLD

In unadjusted analysis, moderate and severe NAFLD were associated with a statistically significant increase in the odds ratio for CKD. This remained significant after adjusting for age, sex and race, but was attenuated after further adjustment for metabolic syndrome components.