Based on a prospective cohort study in middle-aged Chinese men, the current study characterized the dose-response relationships between fat distribution measurements and the incidence of primary liver cancer.
Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated by Cox regression models for the association between waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), a body shape index (ABSI), and body roundness index (BRI) with liver cancer incidence. Dose-response curves were characterized using a restricted cubic spline function.
After a mean follow-up time of 11.9 (SD = 2.4) years, 440 liver cancer cases were identified from 60,625 participants. WC, WHtR, ABSI, and BRI were found to be associated with an increased risk of liver cancer at a given level of body mass index (BMI), with multivariable-adjusted HRs of 1.19 (95% CI: 1.01–1.41), 1.26 (95% CI: 1.02–1.50), 1.12 (95% CI: 1.05–1.23) and 1.28 (95% CI: 1.08–1.53) for per SD increment, respectively. Dose-response curves suggested that the risk increased rapidly above the median levels of WC, WHtR, and BRI. For ABSI, the risk decreased from the minimum level to about the 35th percentile and increased slowly thereafter.
The current study suggested an association between abdominal obesity in middle age and increased risk of primary liver cancer at a given level of BMI. WHtR and BRI were better predictors of liver cancer risk compared with WC and ABSI.
Abdominal obesity in middle age was associated with an increased liver cancer risk at a given level of body mass index.
Dose-response curves suggested that the risk increased rapidly above the median levels of WC, WHtR, and BRI.
WHtR and BRI were better predictors of liver cancer risk than WC and ABSI.
Liver cancer is the 6th most commonly diagnosed cancer and the 3rd cause of cancer death worldwide. Recently released global cancer statistics showed that the estimated numbers of new cases and deaths caused by liver cancer in 2020 are about 906,000 and 830,000, respectively .
Despite hepatitis virus, aflatoxin, and alcoholic drinks , body fatness and its related metabolic complications were increasingly recognized as important risk factors for liver cancer. The association between body mass index (BMI), a measure of total body fatness, and the risk of liver cancer has been extensively investigated . Except for total body fatness, it has been recognized that metabolic status is also affected by fat distribution, particularly abdominal fat deposits. Waist circumference (WC), a well-accepted measure of abdominal obesity, was one of the components of metabolic syndrome and has been suggested to increase the risk of liver cancer independent of BMI . The role of other fat distribution measurements, such as waist-to-hip ratio (WHR), hip circumference (HC), and waist-to-height ratio (WHtR) has also been examined by some epidemiological studies . Recently, new indices for fat distribution have been developed and applied to predict health outcomes. A body shape index (ABSI) and body roundness index (BRI) stand out among these alternative indices for their unique advantages: ABSI reflects the extra effect of abdominal obesity and was independent of BMI by design ; BRI was identified as a good predictor of metabolic syndrome . Nonetheless, no formal study has evaluated the association between ABSI and BRI with liver cancer risk up to now.
Based on the Shanghai Men’s Health Study (SMHS), a large population-based, prospective cohort study conducted in middle-aged Chinese men, the current study aimed to characterize the dose-response relationship between fat distribution measurements and the incidence of primary liver cancer.