Changes in general and central fatness are associated with hepatocellular carcinoma: A Korean nationwide longitudinal study

We investigated the impact of short-term changes in general and central fatness on the risk of hepatocellular carcinoma (HCC) in a large, population-based cohort. We screened 7 221 479 subjects who underwent health examinations provided by the National Health Insurance Service of South Korea in 2009 and 2011. In total, 6 789 472 subjects were included in the final analysis. General fatness was defined as a body mass index (BMI) >= 25 kg/m(2), and central fatness was defined as a waist circumference (WC) >= 90 cm in men and >= 85 cm in women. Subjects were classified according to the change in body fatness between 2009 and 2011, as follows: (a) persistent no fatness as no fatness in both 2009 and 2011, (b) reversed fatness as fatness in 2009, but no fatness in 2011, (c) incident fatness as no fatness in 2009, but fatness in 2011 or (d) persistent fatness as fatness in both 2009 and 2011. During a median 6.4-year follow-up, we documented 9952 HCC cases. Compared to subjects with a persistent no general fatness, the risk of HCC significantly increased in those with incident (adjusted hazard ratio [aHR] = 1.10, 95% confidence interval [CI] = 1.01-1.20) and persistent (aHR = 1.28, 95% CI = 1.23-1.34) general fatness. Compared to subjects with persistent no central fatness, those with incident and persistent central fatness showed a significantly increased risk of HCC (aHR = 1.19, 95% CI = 1.11-1.27 and aHR = 1.33, 95% CI = 1.26-1.40, respectively). Taken together, these findings indicate the importance of strategies for preventing and reversing body fatness to reduce the incidence of HCC.