Short-Term and Long-Term Risk of Diabetes Mellitus among Patients with Spinal Cord Injury: A Nationwide Retrospective Cohort Study

Objectives: Estimating the risk of diabetes mellitus (DM) is important for the proper management of patients with spinal cord injury (SCI). We investigated the short-term and long-term risks of DM among patients with SCI, according to the presence or severity of post-SCI disability and the level of injury. Methods: We conducted a retrospective cohort study using the Korean National Health Insurance Service (2010–2018) database. After matching by age and sex, 6129 SCI patients and 22,979 controls were included. The primary outcome was incident DM, and risk was evaluated for both the short term (within 1 year after SCI) and the long term (after 1 year of SCI diagnosis). Results: The risk of DM was higher among patients with cervical- and thoracic-level SCI accompanied by disability compared to the controls during follow-up (4.6 ± 2.6 years). The short-term risk of DM was higher among patients with SCI (odds ratio [OR] 2.51, 95% confidence interval [CI] 1.91–3.27) than among the controls and it was even higher among patients with severe disability (OR 5.38, 95% CI 2.91–9.27). According to the level of injury, patients with cervical SCI had the highest short-term risk of DM (with disability, OR 4.93, 95% CI 3.07–7.63). There was no significant increase of DM risk in the long term, after 1 year of SCI diagnosis. Conclusions: Patients with SCI accompanied by severe disability and cervical-level injury had higher risks of pronounced DM in the short term. The findings of this study emphasize the need for active surveillance of DM among patients with high-level SCI and disability, especially in the short term, in addition to continuous monitoring and proper management of DM in the long term.