Association Between Obesity and Chronic Kidney Disease, Defined by Both Glomerular Filtration Rate and Albuminuria, in Korean Adults.

BACKGROUND

Chronic kidney disease (CKD) has often been defined based on glomerular filtration rate (GFR) alone. The Kidney Disease: Improving Global Outcomes guideline highlights albuminuria in the CKD definition. Thus, we investigated the association between obesity and CKD, as defined by both GFR and albuminuria, in Korean adults.

METHODS

We used Korea National Health and Nutrition Examination Survey 2011-2014 data (N = 19,331, ≥19 years old) representing the national Korean population. CKD was classified by (1) estimated GFR (eGFR) < 60 mL/min/1.73 m2 (CKDGFR); (2) albumin-to-creatinine ratio (ACR) ≥30 mg/gram (CKDACR); and (3) eGFR < 60 mL/min/1.73 m2 or ACR ≥30 mg/gram (CKDRisk). Associations between obesity and each CKD category were evaluated using multivariate logistic regression analysis.

RESULTS

The prevalence rates of CKDGFR, CKDACR, and CKDRisk were 2.2%, 6.7%, and 8.1%, respectively. Compared with the normal body mass index (BMI; 18.5-22.9 kg/m2) group, men with BMI ≥ 25 kg/m2 had 1.88 times greater risk of CKDGFR in the adjusted model [95% confidence interval (CI), 1.26-2.80; P = 0.002]; BMI was not significantly associated with CKDGFR in women. In contrast, both men and women with BMI ≥ 25 kg/m2 had 1.58 and 1.40 times higher risk of CKDACR (95% CI, 1.21-2.07 and 1.08-1.81, respectively, both P < 0.01). Obese men and women had 1.65 and 1.38 times higher risk of CKDRisk (95% CI, 1.29-2.12 and 1.09-1.75, respectively, both P < 0.01).

CONCLUSIONS

Obesity was significantly associated with an increased ACR-based CKD risk. Longitudinal studies are needed to investigate the role of overweight and obesity in the development and progression of CKD.