To determine the extent of subclinical atherosclerosis in patients with relapsing-remitting multiple sclerosis (RR MS) receiving disease-modifying drugs (DMD).

Multiple sclerosis (MS) and atherosclerosis are inflammatory diseases associated with elevated proinflammatory cytokines. Ongoing inflammation, as seen in MS, may increase the susceptibility to subclinical atherosclerosis as measured by the carotid intima media thickness (IMT). Our previous study displayed an association between serum interleukin-6 levels and IMT in the RR MS group, hinting to a possible inflammatory driven susceptibiliy to subclinical atherosclerosis. However, no statistically significant difference in the IMT at the carotid artery bifurcation (CBIF) was found between the two groups. The long term evolution of IMT in MS and possible protective effects of DMD against atherosclerosis are yet to be explored.

The same group of participants was included as in our previous study. The study group consisted of 104 RR MS patients on DMD without cerebrovascular risk factors. The control group encompassed 43 healthy subjects matched by age and sex selected from hospital personnel. A follow-up ultrasound measurement of IMT at the CBIF was performed on a plaque-free area. Serum was collected for markers of atherosclerosis and inflammation. Individuals with cerebrovascular risk factors other than smoking were excluded from the study.

The mean age of patients was 45.66 ± 8.95 years and 69.2% were female. IMT CBIF was statistically significantly lower (p<0.003) in patients with RR MS (0.733 ± 0.129 mm) compared to the control group (0.819 ± 0.164 mm). No statistically significant difference between the serum markers of inflammation (Erythrocyte Sedimentation Rate, High-Sensitivity C-Reactive Protein) and atherosclerosis (Cystatin C, lipid levels) markers (p>0.05) was found between the groups.

The findings of our five-year follow-up study suggest a possible protective role of DMD in patients with RR MS against the development of subclinical atherosclerosis.