Fracture risk and fracture risk factor assessment among men at prostate cancer diagnosis.

Abstract

Background: Older men with prostate cancer, particularly those receiving androgen deprivation therapy, have an increased fracture risk. However, contemporary studies assessing baseline fracture risk in ethnically diverse populations of men at initial prostate cancer diagnosis remain limited.

Methods: Men aged 50-89 years with newly diagnosed prostate cancer (2010-2022) in a US integrated healthcare system were identified. Demographic data, smoking, prior fracture, rheumatoid arthritis, recent glucocorticoid therapy, body mass index (FRAX variables), and other risk factors (diabetes, low 25OH-vitamin D level) were ascertained from electronic health records. Ten-year risks of hip (10yHIP) and major osteoporotic fractures (10yMOF) were calculated using the US FRAX (race/ethnicity-specific, without bone density); additional scores removed race/ethnicity calibration. High fracture risk was defined as 10yMOF ≥ 20% and 10yHIP ≥ 3%.

Results: Among 25,413 men with prostate cancer (mean age 66.1 ± 8.1 years; 64.8% White, 12.3% Black, 10.7% Hispanic, 11.5% Asian/Pacific Islander (PI)), 87.5%, 3.4%, and 9.1% had local or locally advanced disease, node-positive, and metastatic disease, respectively. Overall, 7.2% smoked, 20.4% had diabetes, and 6.4% had a prior fracture with demographic variation; <1% had rheumatoid arthritis or extended glucocorticoid therapy. Few (0.2%) had 10yMOF ≥ 20% but 11.6% had 10yHIP ≥ 3%, ranging from 15.5% (White), 7.3% (Asian/PI), 4.8% (Hispanic) and 1.4% (Black) and increasing to 14.9% (Asian/PI), 10.9% (Hispanic), and 8.1% (Black) without race/ethnicity calibration. Age was a major risk factor; 20.5% of men aged ≥65 years, increasing to 87.3% of men aged 80-89 years had 10yHIP ≥ 3%. Diabetes and hypovitaminosis D were especially prevalent among non-White populations.

Conclusion: 1 in 9 men with prostate cancer had a high calculated hip fracture risk at diagnosis, increasing to 1 in 5 men aged ≥65 years, with key demographic differences. These observations in real-world populations underscore the importance of skeletal health assessment among older men with prostate cancer and evaluation of fracture risk assessment tools to inform clinical management.