Temporal trend and difference decomposition analysis of hepatocellular carcinoma mortality in Kunshan city of Jiangsu province, 1981-2014

Objective To estimate the temporal trend of hepatocellular carcinoma(HCC) death rates and to quantitatively evaluate influence factors for the mortality in Kunshan city of Jiangsu province from 1981 through 2014.Methods HCC death cases were derived from vital registration data.Crude death rate and age standardized death rate(ASR) of HCC were calculated and annual percent changes(APC) in the rate were estimated for age and gender groups.Difference decomposition method was applied to estimate the contribution of demographic and non-demographic factors to the mortality change.Results The crude mortality of HCC showed no significant temporal trend for total population(APC=-0.1%, 95% confidence interval95% CI:-0.6%-0.4%), the males(APC=-0.1%, 95% CI:-0.6-0.4%), and the females(APC=-0.2%, 95% CI:-0.7%-0.3%)(P>0.05 for all).The age standardized death rate of HCC declined significantly from 1981 to 2014 for total population(30.25/100000 to 14.50/100000; APC=-2.6%, 95% CI:-3.0%--2.2%), for the males(40.69/100000 to 19.70/100000; APC=-2.6%, 95% CI:-3.1%--2.1%), and for the females(21.15/100000 to 9.50/100000; APC=-2.7%, 95% CI:-3.3%--2.1%)(P<0.05 for all).The decrease in the mortality of HCC was due to the combined effect of demographic and non-demographic factors; compared to 1981, the proportion of effect of demographic factor on HCC mortality in 2014 for the males, females and total population were -578.40%, -1403.60%, and -700.37%, respectively.Conclusion The mortality rate of HCC in Kunshan city has declined over the past three decades due to non-demographic factors, but the decline was hindered by demographic factor.