Background: Hip fractures are associated with increased mortality and are a known adverse effect of androgen deprivation therapy (ADT) for prostate cancer (PCa). It was our aim to evaluate how mortality after hip fracture is modified by PCa and ADT.
Methods: PCa dataBase Sweden (PCBaSe 2.0) is based on the National PCa Register and also contains age and county-matched PCa-free men. We selected all men (n = 14,205) who had been hospitalized with a hip fracture between 2006 and 2010; 2,300 men had a prior PCa diagnosis of whom 1,518 (66%) were on ADT prior to date of fracture. Risk of death was estimated with cumulative incidence and standardized mortality ratios (SMRs) to make comparisons with the entire PCa population and the general population.
Results: Cumulative incidences indicated that there was a higher risk of death following a hip fracture for PCa men on ADT than for PCa men not on ADT or PCa-free men, particularly in the first year. The SMRs showed that PCa men on ADT with a hip fracture were 2.44 times more likely to die than the comparison cohort of all PCa men (95%CI: 2.29-2.60). This risk was especially increased during the first month (5.64 (95%CI: 4.16-7.48)). In absolute terms, hip fractures were associated with 20 additional deaths per 1,000 person-years in PCa men not on ADT, but 30 additional deaths per 1,000 person-years for PCa men on ADT, compared to all PCa men.
Conclusion: Hip fractures are associated with higher all-cause mortality in PCa men on ADT than in PCa men not on ADT or PCa-free men, especially within the first three months.