Study: Decline in Cervical Cancer Mortality Among Young Women Suggests Link to HPV Vaccination

A recent study analyzing trends in cervical cancer mortality among US women aged younger than 25 years from 1992 to 2021 found a decline in mortality rates. Between 2016 and 2021, cervical cancer deaths in this group decreased by 62%, suggesting a notable impact of human papillomavirus (HPV) vaccination on reducing mortality in this population.

HPV vaccination has been recommended for routine use in US women since 2006, with prior studies showing a substantial reduction in cervical cancer incidence among young women. Given the decline in incidence and the association between incidence reduction and mortality, this study aimed to evaluate whether similar declines in mortality could be observed in the years following widespread HPV vaccination.

The researchers analyzed cervical cancer mortality data from the National Center for Health Statistics for women aged younger than 25 years between 1992 and 2021. Mortality rates were age-adjusted to the 2000 US standard population and analyzed using the National Cancer Institute's Joinpoint Regression Program. The researchers assessed trends in mortality rates over time and used statistical models to estimate annual percentage changes, identifying significant shifts in mortality trends during specified intervals.

The results indicated a gradual decline in cervical cancer mortality of 3.7% per year from 1992-1994 to 2013-2015. However, between 2013-2015 and 2019-2021, the rate of decline increased, with a 15.2% annual reduction. The total number of cervical cancer deaths decreased from 55 in 1992-1994 to 35 in 2013-2015 and 13 in 2019-2021. When comparing these observed mortality trends to a projected continuation of the prior trend, the researchers estimated that 26 additional cervical cancer deaths would have occurred if the mortality rate had not accelerated after 2015.

The study has several limitations, including its ecological design, which precludes establishing causal relationships between HPV vaccination and mortality reduction. Additionally, the small number of cases in some years, due to the rarity of cervical cancer in young women, and the lack of HPV vaccination data in cancer registries, prevent more detailed analysis of the vaccine’s direct impact on mortality.

“Since the beginning of the COVID-19 pandemic, HPV vaccination coverage has not improved and a troubling decline occurred (from 79.3% in 2022 to 75.9% in 2023) among the most recent generation of US adolescents,” the study authors concluded. “The findings from this study highlight the urgency to improve HPV vaccination coverage.”

Reference

Dorali P, Damgacioglu H, Clarke MA, et al. Cervical cancer mortality among US women younger than 25 years, 1992-2021. JAMA. Published online November 27, 2024. doi:10.1001/jama.2024.22169