Visceral Adipose Tissue Cut Points for Increased Metabolic Risk in Chinese Adults Using Low-Dose Computed Tomography: A Nationwide Multicenter Study.

[INTRODUCTION] Visceral adipose tissue (VAT) is a significant driver for metabolic disease risk. Low-dose computed tomography (LDCT) imaging obtained for other clinical indications is useful for the opportunistic screening of osteoporosis and demonstrates additional potential for the screening of metabolic risk through the measurement of VAT. In this study, we explored LDCT-derived VAT and calculated VAT thresholds indicative of elevated metabolic risk in a population cohort of Chinese men and women.

[METHODS] A total of 21,772 adults (64.2% men, 35.8% women) received a LDCT chest scan for routine lung cancer screening between 2018 and 2019, and abdominal VAT area (L2 region) was derived from these scans using QCT software. The presence of metabolic syndrome (MetS) was ascertained from clinical records and based on the Chinese national guidelines. All data for this current study were obtained from the China Biobank Project, a prospective, nationwide, multicenter population study.

[RESULTS] MetS was prevalent in 29.5% of men and 10.5% of women. Using receiver operating characteristic (ROC) curves, we determined the optimum VAT area cut points for identifying MetS: 210 cm2 in men (odds ratio [OR] 6.15, 95% confidence interval [CI] 5.65, 6.69) and 136 cm2 in women (OR 9.25, 95% CI: 7.58, 11.4). A population attributable risk for MetS by VAT area above sex-specific cut points was 70.9% in men and 74.1% in women. The area under the ROC curves (AUCs) of VAT area for distinguishing MetS are 0.780 (95% CI: 0.772, 0.788) in men and 0.854 (95% CI: 0.842, 0.866) in women, both exceeding the AUCs for body mass index (BMI). ROC curves showed that VAT area demonstrates superiority over BMI and WC in identifying hypertension and hyperglycemia in men, as well as hypertension, hyperglycemia, and hypertriglyceridemia in women.

[CONCLUSION] LDCT-based opportunistic measured VAT area is a superior predictor of metabolic risk, better than BMI and WC, and should be monitored and interventions made to control the metabolic risk. This study proposes VAT risk thresholds for the Chinese population: 210 cm2 for men and 136 cm2 for women.