Patients with fibromyalgia and chronic fatigue syndrome tend to fall into two personality categories, of which one group has more severe symptoms — an insight that might improve both evaluation and treatment of patients based on their specific needs and psychological capabilities.
The study, “Distinctive personality profiles of fibromyalgia and chronic fatigue syndrome patients,” published in the journal PeerJ, underscored that such assessments would conform to the idea of personalized medicine, which is currently gaining ground.
Research in the early 1990s suggested that people have characteristic personality differences based on how they learn in situations of novelty, danger, punishment, and reward. A few earlier studies attempted to link certain personality traits to fibromyalgia, but failed.
Researchers at Tel Aviv Sourasky Medical Center and Ben-Gurion University of the Negev, both in Israel, attempted a different approach to explore how differences in personality may affect fibromyalgia.
The team enrolled 344 patients with self-reported fibromyalgia and chronic fatigue syndrome, who were asked to complete a questionnaire. The survey was completed by 204 patients, and an additional 140 participants provided answers to only parts of the survey.
Researchers used the Fibromyalgia Criteria and Severity Scales (FCSS) to identify patients who met diagnostic criteria for fibromyalgia, finding that 260 participants (75.6 percent) did so. But researchers also noted that those who did not meet the diagnostic criteria had high levels of chronic widespread pain, fatigue, and other fibromyalgia symptoms, indicating it was possible that they represented sub-threshold fibromyalgia cases.
Of the people who did qualify for a fibromyalgia diagnosis, 90.4 percent were women.
The study did not compare fibromyalgia with chronic fatigue syndrome patients, but rather viewed the conditions as overlapping among the study participants.
A tool called Temperament and Character Inventory Revised (TCI-R) was used on the survey, assessing seven different traits. In addition, a questionnaire for type D personality and the Positivity Orientation Scale was used.
Four particular personality aspects were the focus of the study: alexithymia, type D personality, positivity, and social support. Alexithymia is a condition in which a person has difficulty recognizing and describing emotions in her or himself. People with type D personality tend to have more negative emotions and avoid social interactions. Positivity, which is expressed through self-confidence, optimism, and satisfaction with life, and social support were also assessed.
There was no difference in the proportion of participants who had a type D personality between the groups with and without a fibromyalgia diagnosis.
Researchers performed a so-called cluster analysis to see if personality traits could be grouped together and found that the traits could be clumped into two clusters.
One group, composed of 97 people, was characterized by lower levels of self-determination and cooperativeness — the tendency to be agreeable in relations with other people compared to aggressively self-centered and hostile.
People in this group tended to have lower persistence — the capacity of perseverance in spite of fatigue or frustration; fewer tendencies toward sentimentality and dependence on the approval of others; and were more likely to be shy, easily worn out, and worry in a pessimistic way.
They also had higher levels of alexithymia; less social support; lower levels of positivity; and more often had type D personality compared to patients in the other group.
This group of patients had significantly more severe symptoms, but belonging to either group was not linked to differences in health assessment, pain, or levels of physical activity.
“The significant pattern of results indicates at least two distinct personality profiles of FM [fibromyalgia] and CFS [chronic fatigue syndrome] patients,” the team wrote in their report. “Findings from this research may help improve the evaluation and treatment of FM and CFS patients, based on each patient’s unique needs, psychological resources, and weaknesses, as proposed by the current trend of personalized medicine.”