Age Distribution of Disease-Causal HPV Infection in Women With High-Grade Cervical Intraepithelial Neoplasia in Korea
Author(s)
Alhaji Cherif, DPhil1, Xuedan You, PhD1, Seyoung Oh, MD2, Manisha Yadav, MS3, Gargi Baluni, MA3, John Cook, PhD3, GyongSeon Yang, PhD2, Isaya Sukarom, PhD4, Ying Hui Wu, MD, MPH5, Kyung-jin Min, MD, PhD6.
1Merck & Co., Rahway, NJ, USA, 2MSD Korea, Seoul, Korea, Republic of, 3CHEORS, North Wales, PA, USA, 4MSD Thailand, Bangkok, Thailand, 5MSD Taiwan, Taipei, Taiwan, 6Korea University Ansan Hospital, Ansan, Korea, Republic of.
1Merck & Co., Rahway, NJ, USA, 2MSD Korea, Seoul, Korea, Republic of, 3CHEORS, North Wales, PA, USA, 4MSD Thailand, Bangkok, Thailand, 5MSD Taiwan, Taipei, Taiwan, 6Korea University Ansan Hospital, Ansan, Korea, Republic of.
OBJECTIVES: The Human papillomavirus (HPV) vaccine was introduced in Korea in 2007 and incorporated into the National Immunization Program (NIP) for girls aged 11-12 years in 2016. However, unvaccinated females remain at risk for acquiring disease-causal HPV infections. This study aims to estimate the age of acquiring a causal HPV infection that progresses to high-grade cervical intraepithelial neoplasia (CIN).
METHODS: A published discrete event model was modified to track the progression of 1,000 women diagnosed with CIN2+ (CIN2, CIN3, and adenocarcinoma in situ) from causal infection to the onset and diagnosis of CIN2+. The initial age distribution for causal infection was established by shifting the age distribution for CIN2+ diagnosis to an earlier age. The time from infection to disease onset was estimated based on clinical trial data. Diagnosis was determined by the first true positive screening test. The optimal shift was identified based on the goodness-of-fit between the predicted and observed age distribution of CIN2+ diagnosis. Various assumptions regarding the distributions of time from causal infection to disease onset were tested to assess their impact on the results.
RESULTS: The model estimated that only 25% of disease-causal HPV infections that lead to CIN2+ occur before age 30 years, indicating that most causal infections are detected later in life. In the 30-45 age group, each subgroup of 30-35, 35-40, and 40-45 accounted for approximately 14%. Beyond 50 years, the proportion of causal infections declined with increasing age. The model results remained robust to variations in distribution assumptions and were consistent across 10 independent model runs.
CONCLUSIONS: The analysis indicates that a significant burden of disease-causal HPV infection occurs among females aged 30 or older in Korea. These findings highlight the need for ongoing vaccination of females who missed the opportunity in NIP to prevent HPV-related cervical diseases.
METHODS: A published discrete event model was modified to track the progression of 1,000 women diagnosed with CIN2+ (CIN2, CIN3, and adenocarcinoma in situ) from causal infection to the onset and diagnosis of CIN2+. The initial age distribution for causal infection was established by shifting the age distribution for CIN2+ diagnosis to an earlier age. The time from infection to disease onset was estimated based on clinical trial data. Diagnosis was determined by the first true positive screening test. The optimal shift was identified based on the goodness-of-fit between the predicted and observed age distribution of CIN2+ diagnosis. Various assumptions regarding the distributions of time from causal infection to disease onset were tested to assess their impact on the results.
RESULTS: The model estimated that only 25% of disease-causal HPV infections that lead to CIN2+ occur before age 30 years, indicating that most causal infections are detected later in life. In the 30-45 age group, each subgroup of 30-35, 35-40, and 40-45 accounted for approximately 14%. Beyond 50 years, the proportion of causal infections declined with increasing age. The model results remained robust to variations in distribution assumptions and were consistent across 10 independent model runs.
CONCLUSIONS: The analysis indicates that a significant burden of disease-causal HPV infection occurs among females aged 30 or older in Korea. These findings highlight the need for ongoing vaccination of females who missed the opportunity in NIP to prevent HPV-related cervical diseases.
Conference/Value in Health Info
2025-09, ISPOR Real-World Evidence Summit 2025, Tokyo, Japan
Value in Health Regional, Volume 49S (September 2025)
Code
RWD60
Topic Subcategory
Health & Insurance Records Systems
Disease
SDC: Reproductive & Sexual Health