Traumatic spinal cord injury and its correlation to risk of autoimmune/-inflammatory disease

Abstract

Study design: Nationwide epidemiological open cohort study. Objectives: To evaluate whether individuals with traumatic spinal cord injury (TSCI) are more prone to develop autoimmune diseases compared to a general non-TSCI population. Setting: Danish public national registries. Methods: An open nationwide cohort, including individuals born in Denmark from or alive during 1945-2018 was collected and the study period was 1980-2018. Poissons Log-linear regression estimated the incidence rate ratio (IRR) for developing eight groups of autoimmune diseases. A dose-response relationship based on the cervical/thoracic level of injury was assessed by stratification. Results: The cohort included 3,272 individuals with TSCI and 4.8 million background individuals, accounting for 50,865 and 140 million person-years respectively. The TSCI population had an overall IRR of 1.81 (95% CI, 1.59 to 2.05) of getting any autoimmune disease. Subgroup analysis found positive associations for; a) Other neurologic IRR 5.19 (95% CI, 2.79 to 9.65), b) multiple sclerosis IRR 3.70 (95% CI, 2.54 to 5.40), c) Dermatologic IRR 2.57 (95% CI, 1.86 to 3.55), d) Type 1 diabetes mellitus IRR 2.01 (95% CI, 1.54 to 2.61), e) Systemic 1.92 (95% CI, 1.44 to 2.55), and f) Gastroenterologic IRR 1.42 (95% CI, 1.05 to 1.92). Cervical levels of TSCI showed an IRR of 1.70 (95% CI, 1.43 to 2.02), while thoracic levels had an IRR 1.98 (95% CI, 1.63 to 2.39). Conclusions: TSCI may be an individual risk factor of developing an autoimmune disease. There does not appear to exist a dose-response relationship from the level of injury. Sponsorship: None.