School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, PO Box 469, 405 30, Gothenburg, Sweden.
Department of Medicine K2, Solna, 171 76, Stockholm, Karolinska Institutet, Sweden.
Eur J Epidemiol. 2024 Jan;39(1):87-96. doi: 10.1007/s10654-023-01073-6. Epub 2024 Jan 4.
Colorectal cancer (CRC) incurs a significant disease burden globally. Organised CRC screening programmes have been widely implemented for early detection and prevention. To understand the public health impact of these programmes, quantitative evidence of changes in overall and age-specific population incidences is fundamental. We aimed to provide such evidence by exploiting a time lag in the implementation of organised screening in Sweden: two out of 21 regions (these two regions comprise nearly 20% of the total Swedish population) have offered organised screening since 2008; the other regions have offered CRC screening since 2021. Using registry data on diagnosed CRC cases and socio-demographics for all regions in Sweden over the period 1970-2019, Bayesian structural time series modelling and difference-in-differences were applied to analyse the impact of screening on age-specific population incidences over time (CRC cases per 100.000 persons/year). After inviting birth-year cohorts aged 60-69 years for stool-based testing, the incidence rate in the 70-74-year age group decreased significantly over time, with an average reduction of - 44·40 (95% CI - 58·15 to - 31·31) from 2011 to 2019 in the intervention regions. In the overall population aged 60-74 years, there was a net incidence decrease of - 7·99 (95% CI - 13·85 to - 2·39) since the initiation of organised screening in the intervention regions (2008-2019). Organised CRC screening for 60-69-year-olds generated a change in age-specific incidence patterns with a long-lasting incidence decrease in the 70-74-year-old population, implying reductions in the excess mortality and burden of the disease.
结直肠癌（CRC）在全球造成了巨大的疾病负担。有组织的 CRC 筛查计划已广泛实施，以进行早期发现和预防。为了了解这些计划对公共卫生的影响，基本需要定量证据来证明总体和年龄特定人群发病率的变化。我们旨在通过利用瑞典实施有组织筛查的时间差来提供这种证据：21 个地区中的两个（这两个地区占瑞典总人口的近 20%）自 2008 年以来提供了有组织的筛查；其他地区自 2021 年以来提供 CRC 筛查。利用瑞典所有地区 1970 年至 2019 年期间诊断为 CRC 的病例和社会人口统计学的登记数据，我们应用贝叶斯结构时间序列模型和差分分析来分析筛查对随时间推移的年龄特定人群发病率的影响（每 100.000 人/年的 CRC 病例数）。在邀请 60-69 岁的出生年份队列进行基于粪便的检测后，70-74 岁年龄组的发病率随着时间的推移显著下降，在干预地区，2011 年至 2019 年期间的平均降幅为 -44.40（95%CI-58.15 至-31.31）。在 60-74 岁的总体人群中，自干预地区开展有组织的筛查以来（2008-2019 年），总体发病率净下降了-7.99（95%CI-13.85 至-2.39）。60-69 岁人群的结直肠癌有组织筛查导致了年龄特定发病率模式的变化，70-74 岁人群的发病率持续下降，这意味着疾病的超额死亡率和负担有所减少。
