Associations of general obesity and central obesity with the risk of hepatocellular carcinoma in a Korean population: A national population-based cohort study

Numerous previous studies have shown an association between general obesity and hepatocellular carcinoma (HCC). However, relatively few reports on the association of central obesity and HCC are available in Asian populations. Therefore, we investigated the association between WC representing central obesity and the risk of HCC in addition to BMI representing general obesity and the risk of HCC in Korea. A total of 10 505 818 participants who received the National Health Insurance Service (NHIS) health checkups in 2009 were screened for study eligibility, and 26 979 cases of HCC occurred during the 7.3 years of mean follow-up. General obesity increased the risk of HCC with hazard ratios (HRs) of 1.14 (95% CI, 1.11-1.18) for BMI 25.0-<30.0 kg/m² and 1.52 (95% CI, 1.43-1.61) for BMI ≥30 kg/m² compared to those whose BMI is within the normal range. Central obesity was also associated with a higher risk of HCC. For the participants with a WC ≥105 cm in men and WC ≥100 cm in women, the risk of HCC was higher than that of the reference group (HR = 1.69, 95% CI, 1.54-1.85). The HRs were 1.13 (95% CI, 1.07-1.19) for nonobese participants with central obesity, and 1.34 (95% CI, 1.30-1.38) for obese participants with central obesity compared to those without both conditions. Our findings suggest that the risk of HCC increases even more when general obesity is combined with central obesity. Moreover, central obesity is associated with the risk of HCC, regardless of general obesity.