Association of intraabdominal fat with the risk of incident chronic kidney disease according to body mass index among Korean adults.

BACKGROUND: The association between abdominal visceral adipose tissue and the risk of incident chronic kidney disease according to body mass index in the Asian population, remains unclear. We evaluated the impact of abdominal adiposity stratified by body mass index on the risk of incident chronic kidney disease. METHODS: A cohort study included 11,050 adult participants who underwent health check-ups and re-evaluated the follow-up medical examination at a single university-affiliated healthcare center. Cross-sectional abdominal adipose tissue areas were measured using computed tomography. The primary outcome was progression to chronic kidney disease (estimated glomerular filtration rate <60 ml/min/1.73m2). The highest quartile of visceral adipose tissue was used for the cut-off of central obesity. RESULTS: During the mean of 5.6 follow-up years, 104 incident chronic kidney disease cases were identified. The risk for chronic kidney disease incidence was significantly increased in the 3rd and 4th quartile ranges of visceral adipose tissue [hazard ratio (95% confidence interval)]: 4.59 (1.48-14.30) and 7.50 (2.33-24.20), respectively. In the analysis stratified by body mass index, the chronic kidney disease incidence risk was increased in the highest quartile range of visceral adipose tissue in the normal weight group: 7.06 (1.35-37.04). However, there was no significant relationship between visceral adipose tissue and chronic kidney disease in the obese group. Compared to the subjects with normal weight and absent central obesity, the hazard ratio for chronic kidney disease incidence was 2.32 (1.26-4.27) among subjects with normal weight and central obesity and 1.81 (1.03-3.15) among subjects with obesity and central obesity. CONCLUSION: Visceral adipose tissue was a significant risk factor for subsequent chronic kidney disease progression, and the association was identified only in the normal weight group. Normal-weight central obesity was associated with excess risk of chronic kidney disease, similar to the risk in the group with obesity and central obesity.

Impact of Visceral Obesity on the Risk of Incident Metabolic Syndrome in Metabolically Healthy Normal Weight and Overweight Groups: A Longitudinal Cohort Study in Korea.

BACKGROUND: Although both obesity, measured by body mass index, and visceral obesity are known to be major risk factors of metabolic syndrome and its components, there have been debates on the relative contribution of general obesity and visceral obesity to the development of metabolic syndrome. METHODS: We performed a large longitudinal cohort study of 3,093 subjects (age range, 18-65 years) who were metabolically healthy and had a normal weight who received health screenings over a 3-year follow-up period. Cox proportional hazards models were used to estimate the adjusted hazard ratios (HRs) and 95% confidence intervals (CI) for incident metabolic syndrome and its components per sex-specific 1-standard deviation (SD) increase in visceral adipose tissue (VAT) and body mass index. RESULTS: Both obesity and visceral obesity increased the risk of incident metabolic syndrome, but when HR was compared per sex-specific 1-SD, visceral obesity appeared to confer more risk than simple obesity. The HR for 1-SD of body mass index was 1.19 (95% CI, 1.07-1.32; P=0.001) in men and 1.29 (95% CI, 1.10-1.52; P=0.002) in women, while the HR for 1-SD of VAT was 1.29 (95% CI, 1.15-1.44; P<0.001) in men and 1.50 (95% CI, 1.28-1.75; P<0.001) in women. CONCLUSION: Visceral obesity and obesity were longitudinally associated with an increased risk of incident metabolic syndrome among metabolically healthy adults, and visceral fat accumulation appears to be better predictor of metabolic syndrome.