People with excessively flexible joints may be at greater risk of long covid and persistent fatigueindicates research.
Hypermobility is where some or all of a person’s joints have an unusually large range of motion due to differences in the structure of their connective tissues that support, protect and give structure to organs, joints and other tissues.
Up to 20% of adults are hypermobile and many of them are perfectly healthy. Hypermobility can even be beneficial, with many musicians and athletes have very flexible joints. However, it can also create problems, such as an increased tendency to pain, fatigue, joint injuries and stomach or digestive problems.
Dr Jessica Eccles, from the University of Sussex, and her colleagues investigated a possible link between hypermobility, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and fibromyalgia (a condition that causes pain all over the body) when the Covid pandemic hit.
“We started thinking, if hypermobility is possibly a factor in ME/CFS, is it also a factor in long Covid?” Eccles said.
Teaming up with researchers from King’s College London, she examined data from 3,064 participants in the Covid Symptom Study (now the Zoe Health Study) to see if they had hypermobile joints, had fully recovered from their last bout of Covid, and or they experience persistent fatigue.
The research, published in BMJ Public Healthfound that people with hypermobile joints were about 30% more likely to say they had not fully recovered from Covid-19 than those with normal joints, and were significantly more likely to be affected by high levels of fatigue.
Although the study does not prove that hypermobility caused their disease, there is a plausible mechanism by which it may contribute to symptoms such as fatigue, brain fog and postural tachycardia syndrome (PoTS) – where people’s heart rate increases rapidly when they stand up.
Eccles added: “We’ve known for some time that PoTs are closely associated with hypermobility.” The theory is that loose connective tissue in people’s veins and arteries can cause blood to pool in their tissue, meaning the heart has to work harder to pump blood to their brain when they stand up, causing symptoms such as palpitations and dizziness.
“It may be that some of these abnormalities have always been there, but Covid has unmasked them in a vulnerable person,” Eccles said.
One theory she is investigating is whether reduced blood flow to the brain could contributes to brain fog and fatigue in a subset of individuals. However, there are other possibilities.
Eccles said: “We also know that hypermobility is linked to conditions like ADHD and autism, and ME/CFS and fibromyalgia, so fatigue can be a consequence of that.”
She emphasized it long covid was unlikely to be a single entity, but said a better understanding of the link with hypermobility could aid the development of new treatments.
“What this work suggests is that there may be a subgroup of people with long Covid who are more likely to be hypermobile,” she said.
“It is important to identify. It may be that some of the same things that help people with hypermobility and pain, such as strengthening and supporting the core muscles, can help in general.”
