Global, regional, and national bladder cancer burden from 1990 to 2021 and forecasts to 2050: a systematic analysis of the global disease burden study in 2021.

BACKGROUND

Bladder cancer (BCa) remains a global health challenge, marked by geographic variations and evolving epidemiology. Despite new therapies, comprehensive assessments of long-term trends, risk factors, and predictive modeling are scarce. This study aimed to quantify the global, regional, and national burden of BCa in 2021, with stratification by age, sex, and geography. We further assessed temporal trends from 1990 to 2021 and projected future prevalence and mortality up to 2050. Finally, we analyzed demographic and regional disparities to identify high-risk populations and inform targeted prevention and resource allocation.

METHODS

We utilized sex/age-stratified global registry data (29,377 sources) to model mortality via Bayesian spatiotemporal smoothing and incidence through hierarchical regression. DALYs were calculated by integrating mortality and disability using standardized life tables. Multilevel Bayesian age-period-cohort models, incorporating UN population projections and metabolic risk trajectories, generated 2050 estimates, with uncertainty quantified through 1,000 bootstrap replicates.

RESULTS

In 2021, global BCa prevalence was 540,310 cases (95% UI: 494,721-582,579), with an age-standardized prevalence of 0.00635%. Geographic variations were marked: Western Europe reached 0.078% (95% CI: 0.073-0.083%), with six countries exceeding 0.08%, while the United States had the highest at 0.101% (95% CI: 0.095-0.105%), with 31 states surpassing 0.1%. Males bore a substantially higher burden (sex ratio 4.2), with prevalence peaking in ages 85-89 (0.308%, 95% UI: 0.264-0.334%). From 1990 to 2021, the global age-standardized prevalence increased by 4% (95% UI: 2-14%).

CONCLUSION

BCa continues to exert a rising and uneven global burden. Temporal analyses revealed heterogeneous trends across regions, while projections indicate sustained increases by 2050, particularly in aging populations and resource-limited settings. Marked disparities by sex, age, and geography highlight high-risk groups requiring targeted interventions. These findings provide critical evidence to inform global health planning and prevention.