Abstract
BACKGROUND: Kidney cancer (KC) is a major global health concern. Considering the significant impact of premature morbidity and mortality in young adults on the global disease burden, it is essential to conduct a longitudinal study on KC in young adults to develop cost-effective interventions. METHODS: Age-standardized rates (ASRs) including incidence rate (ASIR), mortality rate (ASMR), and disability-adjusted life-years (DALYs) rate (ASDR), and ASDR attributable to risk factors (obesity, smoking, exposure to trichloroethylene, etc.) of KC were analyzed using Global Burden of Disease Study 2021 data (1990-2021), in the whole population and among young adults aged 20-39 years by sex, age, and socio-demographic index (SDI). Mortality to incidence ratio (MIR), percentage change, estimated annual percentage change (EAPC) and the correlation between ASR and SDI were evaluated. Future forecasts of KC burden until 2050 were performed. RESULTS: ASIR among young adults aged 20-39 years increased (EAPC = 1.13%, P < 0.001), ranking second only to those over 80 years old. ASMR declined, with the slowest decrease observed among those aged 20-39 years (EAPC = -0.12%; P = 0.003), mainly due to the upward trend observed among males (EAPC = 0.11%, P = 0.022). No change of ASDR was detected among young adults despite of decreasing trend in the whole population. ASDR attributable to high BMI exhibited an overall increasing trend, particularly among young adults (EAPC = 1.28%, P < 0.001), whereas that attributable to smoking decreased most significantly (EAPC = -1.96%, P < 0.001). High SDI countries contributed the most to this declined trend, however they possess the highest baseline ASRs. ASMR and ASDR continued to rise in middle and low-middle SDI countries. By 2050 young male adults show a significant upward trajectory in KC burden, while the declining trends were observed in the whole population. CONCLUSIONS: This study highlights the urgent need to address the increasing KC burden among young adults, particularly males, as well as in high, middle, and low-middle SDI countries.