Gender differences in brain volume of patients with multiple sclerosis across disease phenotypes (P6.153)

OBJECTIVE: Explore gender differences in brain volume of patients with MS. BACKGROUND: Higher prevalence of MS in women, and a more progressive course in men have been demonstrated previously. Although gender differences in brain volumes have been studies in healthy population, such studies in patients with MS are lacking. DESIGN/METHODS: We used the baseline morphometric 3D-T1-weighted MRI to evaluate the effect of gender on brain volume. MANCOVA was performed as an omnibus test to detect any gender differences on gray matter, white matter, and CSF volumes, adjusting for age, EDSS, and disease duration. Effect of gender and phenotype, i.e relapsing-remitting, secondary progressive, and primary progressive (RRMS, SPMS, PPMS, respectively) on gray matter (GM) and white matter (WM) were explored further using two-way ANOVA. RESULTS: 263 MS patients (174 women, 89 men) were included in the study, with mean±SD age of 42± 10.76 , 42±11.32 , EDSS 174±1.84, 89±1.76, and disease duration of 172 ±8.3, 86±6.8 years for women and men, respectively. A significant gender effect was apparent in the MANCOVA analysis (p = 0.0079). Univariate analysis of GM and WM volumes, after adjustment for the covariates, showed a larger GM volume in women as compared to men in the RRMS and SPMS groups (women: 737±18mm³ for SPMS, 711±5mm³for RRMS, men: 665±25mm³, 694±7mm³, respectively), with a trend towards phenotype interaction (p=0.074, for SPMS augmenting the gender differences). In contrast, WM volumes differences between genders was entirely due to interaction with phenotype (women: 815±15 for SPMS, 824±4 for RRMS, men: 770±21, 829±5, respectively, p= 0.0470 for phenotype-by-gender effect). CONCLUSIONS: GM volume in women with MS is larger than men, irrespective of phenotype, whereas the higher WM volume in women with MS is associated with the SPMS phenotype. Exploration into biological basis of these variations is warranted. Study Supported by: Sastry Foundation Disclosure: Dr. Seraji-Bozorgzad has nothing to disclose. Dr. Bao has nothing to disclose. Dr. Pullukat has nothing to disclose. Dr. Aronov has nothing to disclose. Dr. Bhangu has nothing to disclose. Dr. Santiago Martinez has nothing to disclose. Dr. Chorostecki-Vigrass has nothing to disclose. Dr. Caon has received personal compensation for activities as a speaker, advisor, and consultant. Dr. Zak has nothing to disclose. Dr. Khan has received personal compensation for activities with Biogen Idec, Genzyme, Novartis, and Teva Neuroscience. Dr. Khan has received research funding from National Institutes of Health, National Institute of Neurological Disorders and Stroke, Nati