Predicted Increases in Incidence of Colorectal Cancer in Developed and Developing Regions, in Association With Ageing Populations

Abstract

Population growth and changes in demographic structure are linked to trends in colorectal cancer (CRC) incidence. The aim of this study is to estimate future CRC incidence in the ageing population, and compare trends across developing and developed regions. Cancer and population data were extracted from the International Agency for Research on Cancer. Annual incidence rates for the major types of cancer in 118 selected populations were extracted from 102 cancer registries in 39 countries worldwide. We selected 8 jurisdictions (from the United States, Europe, and Asia) that reported 20-year cancer incidence rates since 1988. Time series models were constructed to project cancer incidence, by sex and age, to 2030. Incidence rates for persons older than 65 years were combined and further adjusted for change of ageing population. We compared age-adjusted incidence rates among the jurisdictions. The total population older than 65 years old was 12,917,794 in 1988, and the number increased by almost 40% to 17,950,115 in 2007. In developed countries in the West CRC incidence is predicted to decrease by 16.3% in the United States, increase by 4.8% in the United Kingdom, and increase by 4.7% in Sweden by 2030. In developing countries, such as China (Shanghai), Croatia, and Costa Rica, CRC incidence is predicted to increase in a steep curve by 2030 because of the growing population and ageing effect; in 2030, the incidence increases were 60.5% for China, 47.0% for Croatia, and 18.5% for Costa Rica. We also predict CRC incidence will increase greatly by 2030 in Japan and Hong Kong, which are developed regions. With the exception of the United States, the incidence of CRC is expected to continue to rise in most regions in the coming decades, due to population growth and changes in demographic structure. The predicted increases are more marked in developing regions with limited health care resources.