The disease course of multiple sclerosis before and during COVID-19 pandemic: A retrospective five-year study

COVID-19 pandemic is thought to influence the natural history of immune disorders, yet the knowledge on its effect on multiple sclerosis (MS) is unknown and not fully understood for which we conducted this retrospective study.

We included all patients with MS seen in King Faisal Specialist Hospital and Research Centre in Jeddah, Saudi Arabia, between January 2017 and October 20201. We determined clinical and radiological evidence of disease activities in all patients by the end of the study period, and we compared the disease patterns before and during the pandemic. We also identified patients with COVID-19 since March 2020, who had at least 3 months of follow-up following the infection.

We studied 301 patients; 216 (72%) were women, the mean age was 38 years (range; 16, 73 years), the mean disease duration was 10 years (range; 1, 36 years), and the median EDSS score was 0.5 (range; 0, 8). RRMS accounted for most of the cases (270 patients). MS disease activities were 25% less prevalent during the pandemic compared to the preceding 3 years (26 vs. 51%, respectively, p < 0.01). Bivariate analysis showed significant higher disease activities in patients younger than 35 years (73 vs 27%), on DMT (68 vs 32%), and complaint to therapy (69 vs 31%). Multiple logistic regression analysis showed that the likelihood of MS disease activities were 3 times more during the pre-pandemic era (adjusted OR = 3.1, p value < 0.05, 95% CI; 1.4, 7.1). Thirty patients (10%) were infected with COVID-19. All patients reported mild symptoms, and none required hospitalization. COVID-19 was prevalent among younger patients with RRMS, with low EDSS scores, irrespective of DMTs they received. COVID-19 infection was not associated with clinical relapses or MRI changes. Disease activities were dependent on DMT use and not COVID-19 status. Multivariate analyses also confirmed no effect of COVID-19 on disease activities (p = 0.3 and 0.4, for clinical and MRI changes, respectively).

MS disease activities did not increase during the pandemic, yet the apparent decrease in the disease activities is probably due to under reporting and not a real decrease in disease activities because of the pandemic. The COVID-19 infection in our MS patients showed a benign disease course, yet standard precautions to reduce the risk of COVID-19 transmission should be applied accordingly.