e18589 Background: Polycythemia vera (PV) is a myeloproliferative neoplasm characterized by overproduction of red blood cells, increased risk of cardiovascular events, and progression to myelofibrosis and acute myeloid leukemia. Determining PV prevalence is essential for characterizing disease burden; however, it is methodologically challenging and inconsistently reported. This study aims to generate contemporary representative estimates of PV prevalence in the United States (US). Methods: A modified life table approach was used to estimate PV prevalence based on delay-adjusted, age-specific incidence and age-of-onset-specific relative survival. Age-specific incidence rates (IR) were derived from the US Surveillance, Epidemiology, and End Results (SEER) database between 2001-2022 using ICD-O-3 histology code for PV of 9950/3 (SEER-21 November 2024 submission). Despite year-to-year variation, joinpoint analyses identified no significant trend in IR over the period 2001-2022. To minimize the impact of IR fluctuations on prevalence estimation, the average IR for 2018-2022 was applied to all years for prevalent estimation. An age-specific delay-adjustment correction factor was applied to IR to account for reporting lags in SEER. Relative survival was derived from 20-year observed PV survival in SEER-21, long-term (21-40 year) observed survival in published data, and expected survival in the general population. Age-specific US population estimates from the United Nations were used to estimate 2025-2030 prevalence. Results: The average age-adjusted IR in 2018-2022 was 1.4 per 100,000 person-years, and with delayed adjustment, 1.7 per 100,000 person-years. Observed age-specific IRs increased with age (Table 1), and the modeled delay-adjustment rate was 18-20% across age groups. The estimated PV prevalence rate in 2025 was 25.6 per 100,000, corresponding to 88,943 patients living with PV in the US. The estimated prevalence rate increased from 25.9 to 27.3 per 100,000 over 2026-2030, with the estimated prevalent cases increasing from 90,522 to 97,011. Conclusions: Using a large, nationally representative data source, we generated contemporary US PV prevalence estimates from 2025-2030, leveraging age-specific incidence, delayed reporting adjustment, and life-table survival modeling. These estimates will support more accurate characterization of disease burden and inform healthcare resource allocation for individuals living with PV in the US. Observed and delay-adjusted average IR by age groups (per 100,000) from 2018-2022 (SEER-21 Nov 2024 submission). Age, years Observed Cases Population Observed IR Delay-adjusted IR 0-29 242 297,902,560 0.1 0.1 30-39 529 106,479,102 0.5 0.6 40-49 1,114 95,845,657 1.2 1.4 50-59 2,067 96,400,850 2.1 2.6 60-69 3,345 83,866,510 4.0 4.8 70-79 2,976 50,604,812 5.9 7.0 80+ 1,872 25,861,928 7.2 8.6
Vachhani et al. (Thu,) studied this question.