MON-788 Fracture Risk Assessment Among Men At The Time Of Prostate Cancer Diagnosis

Disclosure: M.J. Shulman: None. J. Darbinian: None. M. Chandra: None. G.H. Lee: None. J.C. Lo: None. INTRODUCTION: Men with prostate cancer (PCa) are at risk for fracture, especially those treated with androgen deprivation therapy. Studies have examined fracture risk factors and risk scores in smaller cohorts and treated populations, but few have examined fracture risk scores in large populations of men at PCa diagnosis. This study examines baseline fracture risk factors and 10-year fracture risk scores in a community-based population of older men at the time of PCa diagnosis. Methods: In a large US healthcare system, men aged 50-89y with newly diagnosed PCa (2010-2022) and ≥2 years prior health plan enrollment were identified using Cancer Registry data with confirmed pathology. Age, sex, race/ethnicity, current smoking, alcohol intake, body mass index (BMI), diabetes, rheumatoid arthritis (RA), prior fracture, and secondary conditions were ascertained from registry/health record data. PCa was categorized using SEER summary stage: localized, locally advanced, and metastatic disease. 10-year risk of hip fracture (10yHIP) and major osteoporotic fracture (10yMOF) were calculated using the US FRAX (with BMI), and additional scores included (a) diabetes as an RA-risk equivalent and (b) no calibration for race/ethnicity. High-risk thresholds were defined as 10yMOF ≥20% and 10yHIP ≥3%. Results: Among 25,413 men with PCa (mean age 66.1±8.1 at diagnosis), 64.8% were non-Hispanic White (NHW), 12.3% Black, 10.7% Hispanic, 11.5% Asian/Pacific Islander (PI) and 0.8% other/unknown race. Overall, 7.2% were current smokers, 20.4% had diabetes, 6.4% had prior fracture and only 0.5% had RA. Underweight affected 0.3%; the majority had overweight (40.9%) or obesity (31.7%). Fracture risk factors varied by race/ethnicity (alcohol intake higher for NHW; smoking higher for Black; and diabetes nearly 70% higher for Black, Hispanic, and Asian/PI vs NHW). Men with metastatic PCa were older and more likely to have prior fracture and diabetes. There were 11.6% with 10yHIP ≥3% (15.5% of NHW, 1.4% of Black, 4.8% of Hispanic, 7.3% of Asian/PI), but only 0.2% had 10yMOF ≥20% (median 10yMOF 4.8%, interquartile range 3.2-6.2%). Using DM as an RA equivalent increased 10yHIP ≥3% by 2 percentage points; removing race/ethnicity calibration increased 10yHIP ≥3% by 4-6 percentage points among Asian, Hispanic and Black men; but few had 10yMOF ≥20% (overall 0.2-0.3%). Conclusion: 1 in 9 men with PCa had high estimated risk of hip fracture, emphasizing the importance of skeletal health assessment at PCa diagnosis. Key demographic differences were evident, and very few had RA. While FRAX scores increased with diabetes as an RA equivalent and race/ethnicity calibration factors removed, most 10yMOF scores remained below threshold. The impact of BMD on these FRAX scores should be examined. Future studies should also examine whether fracture risk assessment can be optimized, with consideration of risk factors relevant to older men. Presentation: Monday, July 14, 2025