Profiles and disparities of the global cancer and subtypes burden among adults aged 65 years and older: changing patterns in incidence and mortality, 1990–2021

This study aimed to elucidate the global temporal and geographic characteristics of 29 cancers in older people aged ≥ 65 years, based on data from the Global Burden of Disease Study 2021. The average annual percentage changes (AAPCs) were calculated to estimate temporal trends of age-standardized incidence rates (ASIRs) and age-standardized mortality rates (ASMRs). Globally, there was an increase of 8.52 million cancer cases and 3.16 million cancer deaths among older people from 1990 to 2021. The ASIR of cancers combined presented an annually increased trend (AAPC: 0.49%), and regions with high sociodemographic index (SDI) experienced the highest increase (AAPC: 0.94%). Over the same period, the ASMR of cancers combined annually decreased (AAPC: -0.40%) globally, whereas regions with low SDI (AAPC: 0.32%) and low-middle SDI (AAPC: 0.48%) exhibited significantly increased ASMRs. Prostate cancer, lung cancer, and colorectal cancer were the three most common cancers for older people globally, and decreased relative inequalities were observed in higher-SDI countries from 1990 to 2021. For these three cancers, concentration index of ASMR respectively decreased from 0.26 to 0.06, from 0.20 to 0.17, and from 0.24 to 0.18. In contrast, the ASIR and ASMR of these cancers exhibited significant upward trends in lower-SDI regions. Our findings revealed that cancer burden for older people presented disparities globally, where higher-SDI countries faced a greater burden of cancer incidence and lower-SDI countries experienced an upward trend in cancer mortality. More attention should be given to prostate cancer, lung cancer, female breast cancer, and gastrointestinal cancers, especially in lower-SDI regions.