Increased exposure to vascular comorbidity in patients with multiple sclerosis (MS) was associated with markers of neurological dysfunction and neurodegeneration, according to study results published in the Multiple Sclerosis Journal.
Researchers at Johns Hopkins University analyzed data from the MS Partners Advancing Technology and Health Solutions network, a partnership of 7 MS centers in the US and 3 in Europe supported by Biogen. Participants (N = 11,507) underwent MS neuroperformance testing, and a subgroup had magnetic resonance imaging scans (MRIs; n = 6409) that were quantified.
Scores from self-administered neuroperformance tests were normalized with z-scores (equal to 0). Increased vascular comorbidities (³2) were associated with a slower walking speed (standard deviation) [SD]-0.49; 95% CI, -0.78 to -0.19; P = 0.001), manual skill speed (SD, -0.41; 95% CI, -0.57 to -0.26; P <0.0001) and cognitive processing speed (SD, -0.11; 95% CI, -0.20 to -0.02; P = 0.03).
Among the patients with MRI data, 35.7% had hypertension and 11.9% had hypertension with hyperlipidemia.
Quantitative MRI showed that patients with increased vascular comorbidities had reduced brain parenchyma (mean difference) [MD]-0.41%; 95% CI, -0.64% to -0.17%; P = 0.0007) and gray matter fractions (MD, -0.30%; 95% CI, -0.49% to -0.10%; P = 0.0007). Within the gray matter, the volume of the cortical gray matter was reduced (MD, -10.10; 95% CI, -15.42 to -4.78 ml; P = 0.002).
Stratified according to individual comorbidities, patients with diabetes (n = 589) had reduced walking speed (MD, -0.46; 95% CI, -0.78 to -0.15; P <0.0001) and manual dexterity (MD , -0.33; 95% CI), -0.47 to -0.18; P <0.0001) and patients with dyslipidemia (n = 1631) had decreased manual dexterity (MD, -0.14; 95% CI, -0.24 to -0.03; P = 0.01) and processing speed (MD, -0.08; 95% CI, -0.14 to -0.02; P = 0.006). No other vascular comorbidity alone was associated with a decrease in neuroperformance.
This study may have been limited by its cross-sectional nature and the investigator’s strict definitions of comorbidities. Some patients with well-controlled hypertension or diabetes may not have stratified properly.
The study’s authors concluded that their results imply “a burden on vascular comorbidity as a potential contribution to decreased neuroperformance as well as to a lower volume of the compartments of the brain and gray matter, the latter due to its likely relevance to neurodegeneration and the long-term disability is particularly noteworthy. ”
Disclosure: Several authors have stated that they are part of the pharmaceutical industry. For a full list of details, see the original article.
Fitzgerald KC, Damian A, Conway D, Mowry EM. Vascular comorbidity is associated with lower brain volume and lower neuroperformance in a large cohort of multiple sclerosis. Mult Scler. Published online January 8, 2021. doi: 10.1177 / 1352458520984746