Trends in cancer death rate and difference decomposition in Kunshan city, Jiangsu province, 1981 to 2015

Abstract

Objective To explore the temporal trend of cancer death rates in different age and the influencing factors in Kunshan, Jiangsu province, 1981 to 2015. Methods Data were derived from cancer registry and vital registration system. The Chinese age structure in 2000 was used to calculate age-standardized death rates (ASR), and annual percentage changes (APC) and 95% confidence interval (CI) were used to estimate the temporal trend of cancer death rates. Difference decomposition method was applied to analyze the contribution of demographic and non-demographic factors for the change of cancer mortality. Results Between 1981 and 2015, the age standardized all cancers death rate decreased from 162.49 to 93.74 per 100,000 (APC=-1.6%, 95% CI:-1.8%--1.5%). However, the ASR for those aged 70 years or above was stable over time (APC=0.2%, 95% CI: -0.2%-0.5%), whereas aged 30-69 years was decreased from 240.01 in 1981 to 93.28 in 2015 (APC=-2.8%, 95% CI: -3.0%--2.6%). In addition, the proportion of leading cancers were changed obviously. The proportion of lung cancer increased from 1981 to 2015, while gastric cancer, liver cancer, esophageal cancer and colorectal cancer decreased. Compared with the crude cancer mortality in 1993, the effect of the demographic and non-demographic factors to the increased death rate in 2015 were 308.93% and -208.93%, respectively. Conclusion The ASR death rate of all cancers was decreasing, and the rate in those aged 30 to 69 years decreased significantly, whereas stable in those aged 70 years or above. The effect of demographic characteristics on cancer mortality was significantly greater than that of non-demographic characteristics. Key words: Mortality; Age groups; Demographic factors; Difference decomposition