Cervical cancer incidence time trends and age period cohort analysis in Hong Kong Sweden Uganda and the United States

Abstract In 2020, an estimated 604,127 new cases of cervical cancer and 341,831 related deaths occurred worldwide, accounting for 6.5% and 7.7% of all new female cancer cases and deaths, respectively. Global cervical cancer incidence has followed markedly different trajectories across regions, shaped by access to healthcare, screening programs, human papillomavirus (HPV) vaccination, and socioeconomic development. We examined temporal trends and performed age-period-cohort analysis of cervical cancer incidence in Hong Kong, Sweden, Uganda, and the United States. We conducted a time-series analysis of cervical cancer incidence across four populations selected to represent Africa, Asia, Europe, and North America: Hong Kong (1983–2021), Sweden (1970–2022), Uganda (1993–2017), and the United States (1975–2021). Age-specific incidence data were obtained from the Hong Kong Cancer Registry, the Swedish Cancer Registry, the Cancer Incidence in Five Continents Plus (CI5-Plus) database, and the United States Surveillance, Epidemiology, and End Results (SEER) database. Joinpoint regression was used to estimate the average annual percentage change (AAPC) and annual percentage change (APC) with 95% confidence intervals (CI), fitting calendar year as a regression variable to the natural logarithm of the observed incidence rate and testing whether AAPCs differed from zero using a Z-test. Age-period-cohort analysis was performed using a web-based tool developed by the United States National Cancer Institute to assess the independent effects of age, period, and birth cohort on incidence. A total of 67,961 cervical cancer cases were diagnosed across the four populations over the observation period. Age-standardized incidence rates (ASIR) declined significantly in Hong Kong (AAPC − 2.5%, 95% CI -2.7 to -2.3), Sweden (AAPC − 1.1%, 95% CI -1.5 to -0.7), and the United States (AAPC − 1.7%, 95% CI -1.8 to -1.6). In Uganda, incidence rose between 1993 and 2014 before declining modestly from 2014 to 2017, yielding a non-significant AAPC of -0.1% (95% CI -1.8 to 1.8) for the full period. Distinct age, period, and cohort patterns were observed across the four populations. The ASIR of cervical cancer remained well above the World Health Organization elimination threshold of 4 per 100,000 in Uganda and Hong Kong, and slightly above it in the United States. Temporal trends in cervical cancer incidence vary considerably across these four populations, reflecting disparities in the implementation of preventive measures. Incidence is declining in Hong Kong, Sweden, and the United States, consistent with established screening and HPV vaccination programs, while Uganda continues to show a high and inconsistently declining burden. Expanding vaccination coverage, screening access, and treatment capacity in low- and middle-income settings remains essential to achieving global cervical cancer elimination targets.