Latinx with multiple sclerosis have greater disability and loss of deep and cortical gray matter
Daniel Ontaneda1, Marisa McGinley1, Tucker Harvey2, Kathryn Fitzgerald3, Ellen Mowry3, Jeffrey Cohen1, Farren Briggs4
1Cleveland Clinic, 2Quantitative Health Sciences, Cleveland Clinic, 3Johns Hopkins University, 4Case Western Reserve University
To characterize clinical and MRI features of Latinx with multiple sclerosis (MS). 

MS affects an increasing number of Latinx patients. The clinical and radiological phenotype of Latinx MS is not well understood and may have biological or social underpinnings.

A retrospective cross-sectional study in the MS PATHS network was conducted with Latinx and White non-Latinx carrying a diagnosis of MS. Brain MRI conducted within 1 year of clinical visits were included in the MRI cohort. Clinical and quantitative MRI measures were extracted from MS PATHS including age- and education-adjusted processing speed tests. Comparisons between Latinx and White subjects were conducted using two-sample t-test and Wilcoxon rank-sum. Mixed effect models were used to examine clinical and MRI differences between Latinx and White subjects while adjusting for covariates including education, insurance, and employment. 

A total of 660 Latinx and 9957 White subjects were identified with 388 Latinx and 5726 White subjects in the MRI cohort. Compared with White subjects, Latinx were younger (45.4 years [12.2] vs: 52.9 years [12.7], p <0.001), had shorter disease duration (17.2 years [19.6] vs. 19.5 years [11.5], p <0.001), and had lower processing speed z-score (-0.81 [1.3] vs.-0.40 [1.2], p <0.001). Latinx had higher T2 lesion volume (8.0 ml [IQR 3.5-16] vs 6.5 ml [IQR 3.0-14.1], p = 0.009), and lower thalamic volume (12.8 ml [1.7] vs 13.3 ml [1.6], p <0.001) compared to White subjects. Adjusted mixed models showed that Latinx subjects had lower processing speed, brain parenchymal fraction, thalamic volume, cortical volume, and deep gray matter volume (all p <0.001) as well as slower walking speed (p=0.04), non-dominant manual dexterity (<0.01), and higher PDDS (p=0.045).


Latinx, despite being younger and having a shorter disease duration than Whites, had more physical disability, cognitive dysfunction, greater lesion burden, and loss of deep and cortical gray matter.