# Body composition paradox: high muscle mass and adiposity jointly predict incident chronic kidney disease in a Korean cohort

## TL;DR

This study finds that both high muscle mass and high body fat increase the risk of developing chronic kidney disease, challenging the focus on fat alone.

## Contribution

Identifies high muscle mass as a novel independent risk factor for chronic kidney disease in a Korean cohort.

## Key findings

- High muscle mass increases the risk of chronic kidney disease by 2.314 times compared to low muscle mass.
- Metabolic syndrome is associated with a 5.256-fold higher risk of developing chronic kidney disease.
- Leptin levels are significantly higher in individuals who develop chronic kidney disease compared to those who do not.

## Abstract

•First large cohort study to identify high muscle mass as a novel and independent risk factor for incident CKD.•Reveals a body composition paradox: both high adiposity and high muscle mass increase CKD risk.•Gender-specific adipokine roles: Leptin (women) is a stronger predictor than adiponectin.•Metabolic syndrome confers a 5-fold higher risk of developing CKD over 10-years.•Findings challenge the traditional focus solely on fat and highlight muscle mass as a key prognostic factor.

First large cohort study to identify high muscle mass as a novel and independent risk factor for incident CKD.

Reveals a body composition paradox: both high adiposity and high muscle mass increase CKD risk.

Gender-specific adipokine roles: Leptin (women) is a stronger predictor than adiponectin.

Metabolic syndrome confers a 5-fold higher risk of developing CKD over 10-years.

Findings challenge the traditional focus solely on fat and highlight muscle mass as a key prognostic factor.

Diabetes, hypertension, and obesity are common traditional risk factors for Chronic Kidney Disease (CKD). In this population-based longitudinal study, the authors identified risk factors associated with CKD development.

A total of 6,238 Korean adults aged 40- to 69-years without baseline CKD were included. Among them, 4,057 participants with baseline estimated Glomerular Filtration Rate (eGFR) measurements were analyzed. Logistic regression models were used to evaluate significant predictors of CKD.

Over a 10-year follow-up period, CKD developed in 354 subjects (8.7 %). Leptin levels were significantly higher in participants who developed CKD compared to those who did not (8.89 ± 8.00 vs. 6.44 ± 5.52, p < 0.001). After adjusting for confounding factors, logistic regression analysis indicated that participants in the highest quartile of muscle mass were 2.314-times more likely to develop CKD compared to those in the lowest quartile (Odds Ratio [OR = 2.314]; 95 % Confidence Interval [95 % CI: 1.372–3.902]; p = 0.014). In multivariable-adjusted models, the OR for incident CKD when comparing the lowest to the highest quartiles of body fat was 2.166 in men; however, the significance disappeared after adjusting for eGFR. Among women, higher leptin levels and lower adiponectin levels were independently associated with incident CKD (p = 0.003 and p = 0.038, respectively), regardless of traditional CKD risk factors. Furthermore, compared to subjects without CKD, those with metabolic syndrome had an OR (95 % CI) of 5.256 (2.813–9.820) for incident CKD after controlling for confounding factors.

These findings suggest that muscle mass and body fat may serve as better predictors of incident CKD.