Trends in the Mortality of Hepatocellular Carcinoma in the United States.

INTRODUCTION: Primary liver cancer mortality rates have been increasing in the US, but reported decreases among 35-49 year olds may foreshadow future declines. We sought to use age-period-cohort (APC) modeling to evaluate the contribution of cohort effects to hepatocellular carcinoma (HCC) mortality trends in the US.

METHODS: Data on HCC mortality were obtained from the Centers for Disease Control and Prevention National Center for Health Statistics WONDER Online Multiple Cause of Death database, 1999-2015. Crude mortality rates were plotted by gender and age at death. Gender-specific restricted cubic spline APC models were fit to determine influence of birth cohort on incidence of HCC mortality, in reference to the 1940 birth cohort.

RESULTS: Highest mortality rates were found among men ages 70+, with steepest increase in mortality observed among men 55-69 years old. Similar trends were found among females. Accounting for the cohort effect in the APC model markedly improved model fit (likelihood ratio test p < 0.001). Relative to the 1940 birth cohort, risk of mortality due to HCC was significantly higher in later as well as earlier cohorts.

CONCLUSIONS: HCC-associated mortality continues to increase, secondary to an increase in the risk of HCC-associated mortality in more recent birth cohorts among both men and women.