How do the seasons affect the risk of relapse in MS?

Seasonal variation in multiple sclerosis relapse

Harding K, Tilling K, MacIver C, et al

J Neurol 2017; 264:1059-1067

Abstract

Background:

Relapses are a characteristic clinical feature of multiple sclerosis (MS), but an appreciation of factors that cause them remains elusive. In this study, we have examined seasonal variation of relapse in a large population-based MS cohort and correlated observed patterns with age, sex, disease course, and climatic factors.

Results:

Relapse data were recorded prospectively in 2076 patients between 2005 and 2014. 3902 events were recorded in 1158 patients (range 0–24). There was significant seasonal variation in relapse rates (p < 0.0001) and this was associated with monthly hours of sunshine (odds ratio OR 1.08, p = 0.02). Relapse rates were highest in patients under the age of 30 (OR 1.42, p = 0.0005) and decreased with age. There was no evidence of different relapse rates for males compared to females (OR 0.90, p = 0.19).

Conclusion:

Significant seasonal differences in relapse rates highlight the importance of environmental factors in disease expression and should be taken into account when planning clinical trials in which relapse frequency is an outcome. In addition, identification of potentially modifiable factors associated with this variation may offer unique opportunities for alteration of risk of relapse and long-term outcome on a population level, and suggest putative biological mechanisms for relapse initiation.

This reference is now cited in the neurochecklist:

Multiple sclerosis (MS): risk factors and prognosis

Abstract link

Little sunshine. Followtheseinstructions on Flikr. https://www.flickr.com/photos/followtheseinstructions/5928673565
Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s