1,2,3Seraj Makkawi, 1,2Razaz Felemban, 1Ammar Mohammed Aljabri, 1Ghassan Saeed Bin Lajdam, 1Ammar Abdulwadood Albakistani, 1Abdulrahman Ismail Aljohani, 1Suhail Ali Labban

1College of Medicine, King Saud Bin Abdulaziz University for Health Sciences; 2King Abdullah International Medical Research Center, Jeddah, Saudi Arabia; 3Department of Medicine, Ministry of the National Guard-Health Affairs, Jeddah, Saudi Arabia


Multiple sclerosis (MS) is becoming a global subject of study in which some demographic variations are thought to be correlated to its activity. Relapsing remitting multiple sclerosis (RRMS) is the most common demyelinating disorder characterized by periods of exacerbating attacks followed by partial or complete remission. Several factors might play a role in disease progression and relapse frequency such as vitamin D, ultraviolet B radiation, estrogen levels, smoking, obesity and unhealthy lifestyle. In this study, we identified the relationship between seasonal variation and the relapse rate as well as correlated the latter with gender, age, and vitamin D levels in patients with RRMS in Jeddah, Saudi Arabia.

Material(s) and Method(s):

This retrospective study was carried out in the neurological department at King Abdulaziz Medical City (KAMC), Jeddah. The data was collected from 182 patients with RRMS in the period between 2016 to 2021.


219 relapses in 106 (58.2%) patients were documented. The relapse per patient ratio showed a sinusoidal pattern which peaked in February with a rate of 0.76 and troughed in July with a rate of 0.2. There was no evidence of different relapse rates for males compared to females, X2 (1, N = 182) = 1.166a, p = .280. There was a significant negative correlation between vitamin D levels and relapse rate (r= -.312, p =.024).


The relapse rate was higher during the winter months and correlated with low vitamin D levels. Large population-based studies are needed to understand the role of environmental variables in MS exacerbations in Saudi Arabia.