Gender-related differences in MS: A study of conventional and nonconventional MRI measures

Background: Studies showed gender-associated differences in multiple sclerosis (MS) disease evolution and in the evolution of conventional magnetic resonance imaging (MRI) findings. Objective: The aim of this study was to investigate gender differences according to a number of conventional and nonconventional MRI measures in patients with MS. Methods: We examined 763 consecutive patients withMS [499 (19.2% men) relapsing-remitting (RR), 230 (24.8% men) secondary-progressive, and 34 (44.1% men) primary-progressive], 32 (21.9% men) patients with clinically isolated syndrome (CIS), and 101 (30.7% men) normal controls (NC). Patients were assessed using conventional and nonconventional MRI measures. Gender-related MRI differences were investigated using general linear model analysis, corrected for MS disease type. Results: In the total MS group, male patients showed lower normalized peripheral gray matter (GM) (P <0.001) and normalized GM (P = 0.011) volumes than female patients. Female patients presented lower normalized white matter (WM) volumes (P = 0.011). These gender effects were not observed in NC. Male patients also showed more advanced central atrophy (P = 0.022). In RRMS male patients, there was also a higher lateral ventricle volume (P = 0.001). The GM-WM normalized ratio was lower for male patients with MS compared with male NC (0.97 vs. 1.09, P <0.001) but not in patients with CIS compared with NC. Conclusions: There were no significant gender-related differences regarding nonconventional MRI measures. GM and central atrophy are more advanced in male patients, whereas WM atrophy is more advanced in female patients. These gender-related MRI differences may be explained by the effect of sex hormones on brain damage and repair mechanisms.