Seasonal Variations in Multiple Sclerosis Relapses in Oman: A Single Tertiary Centre Experience.

(1) Background and Aims: The seasonal factors influencing multiple sclerosis (MS) relapses remain elusive. This study aims to investigate the seasonal variation of MS relapses in Oman and compare it globally. (2) Subject and Methods: This retrospective study was conducted on N = 183 Omani MS patients treated at Sultan Qaboos University Hospital, a tertiary hospital in Muscat, Oman, over sixteen-year period (2007-2022). Demographic and clinical data of all MS patients were juxtaposed with the monthly weather data during this period, using descriptive and inferential statistical techniques. (3) Results: Among the N = 183 MS patients studied, 508 relapses were recorded during the study period. The average number of relapses per patient was 2.8 (range: 1-15). There were significant seasonal variations in MS relapse rate, with the highest prevalence in the winter months of January and February. However, no correlation was found between MS relapses and other climatic parameters (humidity, temperature, and rainfall). (4) Conclusion: The seasonal patterns of MS relapses in Oman differ from other parts of the world, which the local clinicians should take into account while diagnosing and making management decisions. The potential impact of climate change on the anomalous changes in the seasonality of MS relapses warrants further investigation.