Evolving dynamics of ovarian cancer in midlife women: A three-decade age-period-cohort study.
BACKGROUND Ovarian cancer, being the most lethal female-specific cancers, presents a significant health threat to midlife women undergoing the menopause and perimenopause transition. This study aims to investigate the patterns and trends of ovarian cancer among this population from 1990 to 2021. METHODS Using 1990-2021 data, we calculated age-standardized rates (ASRs) and estimated annual percentage changes (EAPCs) for ovarian cancer among midlife women, including those aged 40-59 years (encompassing the perimenopausal transition) and those aged 45-54 years (the typical menopausal age range). Temporal trends in incidence, mortality, prevalence, and disability-adjusted life years (DALYs) were analyzed using joinpoint regression to identify significant inflection points, age-period-cohort modeling to estimate independent effects of age, period, and birth cohort, and Bayesian age-period-cohort projections to forecast disease burden up to 2035. RESULTS From 1990 to 2021, new ovarian cancer cases among women aged 45-54 years increased by 92.6% and among those aged 40-59 years by 90.4%, while ASRs declined (incidence EAPC: -0.46 and -0.42, respectively). An inverted U-shaped relationship between socio-demographic index (SDI) and burden was observed: ASRs decreased in high-SDI regions but increased in low-middle SDI areas. The 55-59-year age group consistently carried the highest burden, accounting for approximately 35% of incident cases and 40% of deaths among midlife women. Cohort effects showed a progressive decline in risk for women born after 1956. Bayesian projections predict continued global increases in new cases, deaths, and DALYs from 2022 to 2035, with rising ASRs for incidence and prevalence. CONCLUSION This pioneering analysis of Global Burden of Disease Study 2021 data reveals persistent socioeconomic disparities, distinct age-specific patterns (peak burden at 55-59 years), and ongoing epidemiological transitions in ovarian cancer among midlife women. Based on our findings, potential public health priorities could include sustaining recent progress in high-SDI regions to maintain declining trends and enhancing diagnostic capacity and risk-factor management in low-middle SDI settings to counter rising burden. These population-level patterns might further research and health policy planning tailored to regional sociodemographic contexts.