Osteoporosis and osteopenia in young adults with spinal cord injury: The necessity of an early bone mineral density checkup

Objective: To identify the prevalence and risk factors for low bone density (LBD) in young adults with spinal cord injury (SCI). Design: Retrospective cross-sectional study. Setting: National Rehabilitation Center in Seoul, Korea. Participants: SCI patients aged 20-49 years hospitalized from January 2010 to October 2021. Interventions: Bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry of the lumbar spine, femoral neck, and total hip. Outcome Measures: Areal BMD, Z-score and T-score of each region and prevalence of LBD. Results: Osteopenia and osteoporosis were diagnosed in 451 (58.2%) and 156 (20.1%) of 775 patients, respectively. Among 181 patients within 3 months of onset, 105 (58%) and 20 (11%) were diagnosed with osteopenia and osteoporosis, respectively. Additionally, the percentage of LBD increased significantly as the time from injury increased. On multivariate analysis, the risk factors for LBD in patients with early SCI within 12 months of onset were female sex (odds ratio [OR] = 2.49; 95% confidence interval [CI], 1.34-4.46; p = 0.002), body mass index (OR = 0.86; 95% CI, 0.81-0.92; p < 0.001), and age (OR = 1.04; 95% CI, 1.01-1.07; p = 0.005). Alcohol or smoking history, etiology, neurological level, or completeness of injury, and the Korean version of the spinal cord independence measure-III score were not significantly correlated with LBD. Conclusions: The prevalence of osteopenia and osteoporosis is high in young adults with SCI. In addition, the diagnosis rate is high in the test performed at the initial stages after injury. Therefore, early bone health monitoring should be performed in young adults with SCI.