2023 HSR&D/QUERI National Conference

4050 — Ischemic stroke incidence in US Veterans living with spinal cord injury: Preliminary data

Lead/Presenter: Rafer Willenberg,  Harvard Medical School, Boston MA; Spaulding Rehabilitation Hospital, Charlestown MA; VA Boston Healthcare System, Boston MA
All Authors: Willenberg R (Harvard Medical School, Boston MA; Spaulding Rehabilitation Hospital, Charlestown MA; VA Boston Healthcare System, Boston MA,), Smith B (Center of Innovation for Complex Chronic Healthcare (CINCCH), Hines VA Hospital, Hines, IL; Center for Healthcare Studies, Institute of Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL), Stroupe K (Center of Innovation for Complex Chronic Healthcare (CINCCH), Hines VA Hospital, Hines, IL; Parkinson School of Health Science and Public Health, Loyola University Chicago, Maywood, IL), Sippel JL (Spinal Cord Injuries & Disorders National Program Office (11SCID), Veterans Health Administration, Washington, DC), Huo Z (Center of Innovation for Complex Chronic Healthcare (CINCCH), Hines VA Hospital, Hines, IL), Sabharwal S (Harvard Medical School, Boston MA; VA Boston Healthcare System, Boston MA)

Objectives:
People with spinal cord injuries and disorders (SCI/D) have been reported to have an elevated risk of ischemic stroke, based on a study in the population of Taiwan [Wu et al, Neurology. 2012;78:1051–1057]. This prior study reported a cumulative incidence rate of ischemic stroke of 1.9% over 4 years in people with SCI, vs 0.6% in matched controls. We initiated this preliminary study to estimate the 4-year incidence of ischemic stroke and to elucidate associated risk factors in United States (US) Veterans living with SCI/D.

Methods:
We used the Veterans Health Administration Service Support Center (VSSC) SCI/D Registry and the Veterans Health Administration (VHA) Enterprise Corporate Data Warehouse (CDW) to examine the incidence of new ischemic stroke in Veterans living with SCI between fiscal years (FY) 2018-2021. Veterans in this cohort were alive by the end of FY 2021. Veterans with ischemic strokes were identified using ICD-10 codes for cerebral infarction or sequalae of cerebral infarction. The diagnosis of sequelae of cerebral infarction was used with the intent of being inclusive of Veterans who may have first presented for stroke care to non-VA facilities. Veterans having a history of stroke noted by diagnoses of ischemic strokes or stroke sequelae during FY 2013-2017 were excluded. Statistical analyses included frequencies and multiple regression models.

Results:
From FY 2018-2021, 394 of 12,547 Veterans with SCI had a newly-recorded ischemic stroke diagnosis, reflecting a 4-year incidence of 3.14%, and an average annual incidence of 0.79%. Compared to Veterans < 40 years of age with SCI/D, Veterans >85 years old with SCI/D had a 13.92 Incidence Rate Ratio (IRR) of stroke (95%CI: 5.09 – 38.11). Compared to Veterans with traumatic SCI, Veterans with non-traumatic SCI/D had a higher likelihood of ischemic stroke (IRR = 1.43, 95%CI: 1.13 – 1.80).

Implications:
US Veterans living with SCI/D have a higher incidence of ischemic stroke than that reported for the Taiwanese population with SCI. Within the population of Veterans with SCI/D, older Veterans and those with non-traumatic SCI/D have a notably higher stroke risk.

Impacts:
Clinicians should have a heightened awareness for the risk of ischemic stroke in Veterans with SCI/D, particularly in older adults and those with non-traumatic SCI. Further study is underway to evaluate ischemic stroke risk in Veterans with SCI/D relative to ischemic stroke risk in age- and sex-matched US Veterans without SCI. Additional study is needed to elucidate physiologic vs non-physiologic etiologies of stroke risk in Veterans with SCI/D, particularly in consideration of whether increased frequency of preventive care is needed, or whether persons with SCI/D should have additional diagnostic testing, screening and interventions to mitigate their stroke risk.