[Fractions and trends of cancer burden attributable to population ageing in China].

Objective: To analyse the fractions and trends of cancer burden attributable to population ageing, adult population size, age-specific incidence and case fatality rate in China between 1990 and 2019. Methods: We extracted data from the database of Global Disease Burden Study, including the number of cancer cases, deaths and corresponding population of 29 cancer types for Chinese adults aged 25 years and older from 1990 to 2019. Using the cancer deaths in 1990 as a reference, we employed a decomposition method to express cancer deaths as the product of four factors among men and women from 1991 to 2019. The fractions attributable to cancer deaths among total cancer deaths in that year were calculated and its time trends were assessed. Results: In 2019, we estimated that there were 2 690 000 cancer deaths among adults aged 25 and older in China. Of which, cancer deaths attributable to population ageing, adult population size, age-specific cancer incidence and case fatality rate were 740 000 (27.5% of total cancer deaths in 2019), 1 091 000 (40.6%), 198 000 (7.3%) and -728 000 (-27.1%), respectively. In 2019, lung cancer, stomach cancer, esophageal cancer, liver cancer and colorectal cancer ranked the top five cancers among population ageing attributable to cancer deaths. For 29 cancer types, the fractions of population ageing attributable to cancer deaths among total deaths of that cancer were ranged from 9.3% to 40.5%. The ageing attributable to cancer deaths and its fractions were increased rapidly since 1997, while those estimates were negative before 1997. Conclusions: The population ageing process in China was one of the major contributors to the increase in cancer burden in recent years, which has caused more cancer deaths than that by age-specific cancer incidence. Accordingly, activities toward healthy ageing would be the key to cancer prevention and control.目的： 分析中国1990—2019年恶性肿瘤负担变化归因于人口老龄化、人口数增长、恶性肿瘤年龄别发病率、病死率的比例及趋势。 方法： 从全球疾病负担研究中提取1990—2019年中国≥25岁人群中29种恶性肿瘤的发病数、死亡数及其对应的人口数，以1990年为基准参照，采用因素分解法计算1991—2019年男性和女性中各恶性肿瘤历年可归因于人口老龄化、人口数增长、恶性肿瘤年龄别发病率、病死率的死亡数，并计算历年归因恶性肿瘤死亡数占当年全部恶性肿瘤死亡数的比例及其时间变化趋势。 结果： 2019年中国≥25岁人群恶性肿瘤死亡总数为269.0万例，其中归因于人口老龄化、人口数增长、恶性肿瘤年龄别发病率及病死率的恶性肿瘤死亡数分别为74.0万、109.1万、19.8万和-72.8万，分别占2019年总死亡数的27.5%、40.6%、7.3%和-27.1%。2019年人口老龄化归因死亡数前5位的恶性肿瘤分别为肺癌、胃癌、食管癌、肝癌和结直肠癌，29种恶性肿瘤归因于人口老龄化的死亡数占该癌种死亡总数的比例为9.3%~40.5%。归因于人口老龄化的恶性肿瘤死亡数及其占全部恶性肿瘤死亡数的比例在1997年前为负值，而从1997年开始为正值且逐年快速增加。 结论： 中国人口老龄化进程是近年来恶性肿瘤负担增加的主要驱动因素之一，其作用已经超过了发病率本身的增长，健康老龄化是恶性肿瘤防治不可或缺的关键一环。.