Burden and Trends of Crohn’s Disease Among Women of Reproductive Age in China, India, and the United States, 1990–2023, with Projections to 2040: A Systematic Analysis for the Global Burden of Disease Study 2023

Purpose: Crohn's disease (CD) represents a growing public health concern, yet comprehensive epidemiological data on women of reproductive age are limited. This study aimed to explore the incidence trends and underlying drivers of CD among women of reproductive age in China, India, and the United States (US). Patients and Methods: Using data from the Global Burden of Disease (GBD) Study 2023, we analyzed age-standardized incidence rates (ASIR), prevalence, and disability-adjusted life years (DALYs) from 1990 to 2023. Temporal trends were assessed using the estimated annual percentage change (EAPC) and Joinpoint regression analysis. A decomposition analysis was conducted to evaluate the influencing factors, and a Bayesian Age-Period-Cohort (BAPC) model was utilized to project trends through 2040. Results: Globally, CD incidence among women of reproductive age showed a slow upward trend. China experienced the most rapid increase (EAPC 2.89; 95% CI: 2.23-3.55), with ASIR rising from 0.29 to 0.70/100,000. Increases were modest in India (EAPC 0.99; 95% CI: 0.79-1.18) and the US (EAPC 0.41; 95% CI: 0.22-0.61). Joinpoint regression identified varying temporal patterns across countries. Peak incidence occurred earlier in China (ages 35-39) compared to the US and India (ages 40-44). Decomposition analysis attributed China's increasing burden primarily to epidemiological changes, whereas demographic factors drove trends in the US and India. By 2040, China's ASIR is projected to reach 0.74/100,000, while the US rate is expected to decline. Notably, age-standardized DALY rates will decrease across all three countries, though the reduction in China was marginal compared to the US. Conclusion: The present study characterizes both distinct regional patterns of CD evolution as well as age-related changes in its course. The association with the peak period of fertility also highlights the need to have localized plans and multidisciplinary models of care.