The Relationship Between Spinal Cord Atrophy and Cardiovascular Risk

Lower brain volume is associated with various cardiovascular (CV) risk factors, but less is known about the spinal cord (SC). Concomitant SC atrophy may contribute to motor weakness and slowness that are prominent features of frailty, known to increase mortality. The objectives of this study were to determine potential relations between SC size, age, individual CV risk factors, and overall CV risk.  Methods and results: We retrospectively reviewed 121 patients (age 60 ± 13 years, 75.2% females) who were referred to our institution for magnetic resonance imaging (MRI) of the cervical SC. Patients with known degenerative neurological or congenital disease were excluded from review. CV risk factors were obtained from medical records, and the Atherosclerotic Cardiovascular Disease (ASCVD) risk score was calculated. Cross-sectional SC area (SCA) was traced on each slice of the C2-C6 cervical images with electronic calipers and averaged. Mean SCA was inversely correlated with age (r = -.19; p = .04) and creatinine level (r = -.20; p = .03), but not with height (r = .04; p = .69), weight (r = .03; p = .72), or body mass index (r = .02; p = .80). There was a stepwise decrease in SCA in patients without hypertension (HTN) or diabetes mellitus (DM) (n = 23) compared to those with only HTN (n = 55) (84.4 ± 9.4 mm² vs 79.6 ± 11.2 mm²) and to patients with DM and/or HTN (n = 43) (84.4 ± 9.4mm² vs 76.6 ± 8.3mm² (p = .01). On multivariate regression, DM was an independent predictor of lower SCA (β = -4.4; p = 0.03), and there was a trend toward lower SCA in patients with only HTN (β = -4.0; p = 0.1) (p = 0.02 for the multivariate model after adjusting for age and creatinine). Among 74 patients with ASCVD risk scores, SCA had a moderate inverse correlation with the ASCVD score (r = -.42; p < 0.001), which remained an independent predictor of lower SCA on multivariate analysis (β = -2.9; p = 0.002).  Conclusion: Lower SCA appears related to existing DM and possibly HTN, as well as overall CV risk. SC atrophy in patients with CV disease and risk factors may contribute to frailty, which is associated with increased mortality. This study is subject to the limitations of a retrospective cross-sectional study of a relatively small sample size.