Impact of splenectomy on fracture risk via the bone-immune axis: A nationwide Korean cohort study.

Abstract

Splenectomy compromises bone health by disrupting the immune-bone axis. In this nationwide cohort study, splenectomy was associated with increased risk of fractures, particularly hip fractures, with the strongest association observed after traumatic splenectomy. These findings support the need for bone quality monitoring and preventive strategies in post-splenectomy patients. Splenectomy may interfere with immune-mediated bone remodeling, potentially compromising bone quality and strength. However, large-scale, long-term evidence linking splenectomy to bone health remains limited. We aimed to investigate the association between splenectomy and fracture incidence using a nationwide cohort. The analysis included 3,125,549 individuals who participated in national health screenings conducted by the Korean National Health Insurance Service, of which 769 had undergone splenectomy. The primary outcome was the incidence of new-onset fractures (hip, vertebral, or other fractures). Multivariable Cox proportional hazards models were used to assess fracture risk, adjusting for potential confounders. Over a median follow-up of 10.3 years, the splenectomy group exhibited a significantly increased risk for any fracture (hazard ratio [HR] 1.61, 95% confidence interval [CI] 1.33-1.95), hip fracture (HR 2.57, 95% CI 1.76-3.76), and other fractures (HR 1.36, 95% CI 1.05-1.76). Although splenectomy was not significantly associated with vertebral fracture risk in the overall population, analyses stratified by the indication of splenectomy revealed a pronounced increase in risk among individuals who underwent traumatic splenectomy, with a 3.27-fold higher risk of vertebral fracture (95% CI 1.06-10.15) and a 7.86-fold higher risk of hip fractures (95% CI 2.95-20.95). Subgroup analyses identified significantly higher vertebral fracture risks among males and current drinkers. Our findings indicate that splenectomy is associated with an increased risk of fractures, particularly hip fractures, with the association being most pronounced among individuals who underwent traumatic splenectomy. These findings highlight the necessity of individualized bone health monitoring and targeted preventive strategies for post-splenectomy patients.