The effect of level of injury on diabetes incidence and mortality after spinal cord injury – a longitudinal cohort study

Study design: Retrospective longitudinal cohort study of veterans with SCI. Objectives: Spinal cord injury (SCI) is associated with an increased risk of developing diabetes mellitus (DM), likely due to body composition alterations and autonomic nervous system dysfunction. These factors are more pronounced in persons with tetraplegia (TP) versus paraplegia (PP). However, the effect of level of injury (LOI) on DM incidence is largely unknown. Therefore, the objective is to examine the effect of LOI on DM incidence in persons with SCI. Setting: South Texas Veterans Health Care System. Methods: We obtained electronic record data on age, sex, race/ethnicity, LOI and HbA1c concentration from January 1st 2001 through December 31st 2021. Cox proportional hazard regression analyses were used to assess the association between LOI, DM and all-cause mortality. Results: Among 728 non-diabetic veterans with SCI (350 TP/ 378 PP, 52 ± 15 years, 690 male/38 female) 243 developed DM, of which 116 with TP and 127 with PP. Despite chronological variations between TP and PP, DM risk over the entire follow-up did not differ between the groups (hazard ratio (HR): 1.06, 95% CI: 0.82–1.38). Mortality was higher in TP versus PP (HR: 1.40, 95% CI: 1.09–1.78). However, developing DM did not increase the risk of death, regardless of LOI (HR: 1.07, 95% CI: 0.83–1.37). Conclusion: Despite chronological variations between both groups, the level of injury had minimal effect on long-term DM development in this cohort of veterans with SCI. Sponsorship NIH (DK105379; MS), RR&D SPiRE (I21RX003724-01A1; MT and SH).