Sex-specific impact of dietary patterns on liver cancer incidence: updated results from two population-based cohort studies in China

Purpose The associations between dietary patterns and liver cancer risk have received much attention, but evidence among the Chinese population is scarce. This study aims to update the results of two cohort studies and provide the sex-specific associations in the Chinese population. Methods This study was based on two cohorts from the Shanghai Men’s Health Study (SMHS) and the Shanghai Women’s Health Study (SWHS). Diet information was collected by validated food frequency questionnaires. Dietary patterns were derived by factor analysis. Cox regression model was utilized to estimate the hazard ratio (HR) and 95% confidence interval (CI) for associations between dietary patterns and liver cancer risk. Results During median follow-up years of 11.2 (male) and 17.1 (female) years, 427 males and 252 females were identified as incident primary liver cancer cases. In males, vegetable-based dietary pattern was inversely associated with liver cancer (HR Q4-Q1 : 0.67, 95%CI 0.51–0.88, P trend < 0.001). Interaction analysis indicated that in males lower vegetable-based dietary pattern score and older age/medical history of chronic hepatitis combined increase the hazard of liver cancer more than the sum of them, with a 114% and 1061% higher risk, respectively. In females, the fruit-based dietary pattern was associated with a reduced risk of liver cancer (HR Q4-Q1 : 0.63, 95%CI 0.42–0.95, P trend = 0.03). In both males and females, null associations were observed between the meat-based dietary pattern and the risk of liver cancer. Conclusion A vegetable-based dietary pattern in males and a fruit-based dietary pattern in females tended to have a protective role on liver cancer risk. This study provided updated information that might be applied to guide public health action for the primary prevention of liver cancer.