BACKGROUND & AIMS
Despite the significant association between obesity and several cancers, it has been difficult to establish an association between obesity and hepatocellular carcinoma (HCC). Patients with HCC often have ascites, making it a challenge to accurately determine body mass index (BMI), and many factors contribute to the development of HCC. We performed a case–control study to investigate whether obesity early in adulthood affects risk, age of onset, or outcomes of patients with HCC.
METHODS
We interviewed 622 patients newly diagnosed with HCC from January 2004 through December 2013, along with 660 healthy controls (frequency-matched by age and sex) to determine weights, heights, and body sizes (self-reported) at various ages before HCC development or enrollment as controls. Multivariable logistic and Cox regression analyses were performed to determine the independent effects of early obesity on risk for HCC and patient outcomes, respectively. BMI was calculated, and patients with a BMI ≥30 kg/m2 were considered obese.
RESULTS
Obesity in early adulthood (age, mid-20s to mid-40s) is a significant risk factor for HCC. The estimated odds ratios (OR) and 95% confidence intervals (CI) were 2.6 (1.4–4.4), 2.3 (1.2–4.4), and 3.6 (1.5–8.9) for the entire population, men, and women, respectively. Each unit increase in BMI at early adulthood was associated with a 3.89-month decrease in age at HCC diagnosis (P<.001). Moreover, there is a synergistic interaction between obesity and hepatitis virus infection. However, we found no effect of obesity on the overall survival of patients with HCC.
CONCLUSION
Early adulthood obesity is associated with increased risk of developing HCC at a young age in the absence of major HCC risk factors, with no effect on outcomes of patients with HCC.