Population growth and changes in demographic structure are linked to trends in colorectal cancer incidence.
Dr Joseph Sung and colleagues from Hong Kong estimated future colorectal cancer incidence in the ageing population, and compared trends across developing and developed regions.
The team extracted cancer and population data 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.
The team selected 8 jurisdictions that reported 20-year cancer incidence rates since 1988.
Time series models were constructed to project cancer incidence, by sex and age, to 2030.
|The incidence increases were 61% for China|
|Clinical Gastroenterology & Hepatology|
Incidence rates for persons older than 65 years were combined and further adjusted for change of ageing population.
The research team compared age-adjusted incidence rates among the jurisdictions.
The team found that 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 colorectal cancer incidence is predicted to decrease by 16% in the United States, increase by 5% in the United Kingdom, and increase by 5% in Sweden by 2030.
The researchers observed that in developing countries such as China, Croatia, and Costa Rica, colorectal cancer 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 61% for China, 47% for Croatia, and 19% for Costa Rica.
The team also predicted that colorectal cancer incidence will increase greatly by 2030 in Japan and Hong Kong, which are developed regions.
Dr Sung's team concludes, "With the exception of the United States, the incidence of colorectal cancer 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."