Incidence trend and age-period-cohort analysis of reported hepatitis C among residents aged 30 to 79 in northeastern China, 2008 to 2017

The purpose of this study was to acquire the epidemic trend of age-standardized reported incidence and to analyze the age effect, period effect, and cohort effect on the reported incidence of hepatitis C in Jilin Province, China. We collected the annual reported incidence data of hepatitis C by gender (2008-2017). Annual percentage change and annual average percentage change were calculated by joinpoint Poisson regression analysis. The age effect, period effect, and cohort effect on the incidence of hepatitis C were estimated by an age-period-cohort model, and the relative risk was determined. Joinpoint regression analysis showed that the age-standardized reported incidence of hepatitis C indicated a declining trend integrally. Among people aged 30 to 44 (youth), the incidence trend declined the fastest, while trends declined the slowest among women and the overall population aged over 66 (elderly people) and men aged 45 to 65 (middle-aged group). The results of the age-period-cohort model showed that the reported incidence increased first and then decreased with age. Throughout the period, the risk of hepatitis C also increased first and then decreased. Compared with the median birth cohort of the same age group, the birth cohort of the patients with the highest incidence of hepatitis C was in the 1930s, followed by the 1940s and 1950s. The birth cohort of the patients with the lowest incidence was in the 1980s, followed by the 1970s and 1960s. Although the overall reported incidence trend of hepatitis C is declining and the risk of the young birth cohort is low, many factors affecting infection and testing with hepatitis C still exist in China. We should focus on high-risk population management and formulate corresponding public health strategies to accelerate the implementation of the global health strategy to eliminate hepatitis C published by the World Health Organization.