An international research team has discovered that reduced levels of serotonin in the blood may be linked to heightened somatic awareness, a condition where people experience physical discomforts for which there is no physiological explanation.
Symptoms of heightened somatic awareness may include headaches, sore joints, nausea, constipation or itchy skin. Patients are also twice as likely to develop chronic pain, as the condition is associated with illnesses such as fibromyalgia, rheumatoid arthritis and temporomandibular disorders. The illness tends to cause great emotional distress, particularly since patients are often told it’s “all in their head.”
“Think of the fairy tale of the princess and the pea,” said Dr. Samar Khoury, a postdoctoral fellow at McGill University’s Alan Edwards Centre for Research on Pain.
“The princess in the story had extreme sensitivity where she could feel a small pea through a pile of 20 mattresses. This is a good analogy of how someone with heightened somatic awareness might feel; they have discomforts caused by a tiny pea that doctors can’t seem to find or see, but it’s very real.”
The study, recently published in the Annals of Neurology, found that patients who suffer from somatic symptoms share a common genetic variant. The mutation leads to the malfunctioning of an enzyme important for the production of serotonin, a neurotransmitter with numerous biological functions.
“I am very happy and proud that our work provides a molecular basis for heightened somatic symptoms,” said Dr. Luda Diatchenko, lead author of the new study and a professor in McGill’s Faculty of Dentistry.
“We believe that this work is very important to patients because we can now provide a biological explanation of their symptoms. It was often believed that there were psychological or psychiatric problems, that the problem was in that patient’s head, but our work shows that these patients have lower levels of serotonin in their blood.”
The findings have laid the groundwork for the development of animal models that could be used to better characterize the molecular pathways in heightened somatic awareness. But mostly, the researchers hope their work will pave the way for treatment options.
“The next step for us would be to see if we are able to target serotonin levels in order to alleviate these symptoms,” said Diatchenko, who holds the Canada Excellence Research Chair in Human Pain Genetics.
Source: McGill University