Meta-analysis of recent studies into post-exertional malaise (PEM) reveals it as a unique, defining feature of ME/CFS
Post-exertional malaise (PEM), refers to a worsening of ME/CFS symptoms following even just minimal physical or mental exertion, which can be delayed 24-72 hours or more.
While for most conditions, patients experience some relief in their symptoms after exercise, the opposite is true for people with ME/CFS and fibromyalgia. for whom sometimes even the slightest exertion can cause a flare-up of symptoms. People with ME/CFS often refer to these post-exertional setbacks as ‘crashes’. Recovering from these ‘crashes’ is often prolonged and can take days, weeks or sometimes months.
A meta-analysis of a number of the recent studies on PEM has identified it as a condition unique to people with ME/CFS.
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