Women with fibromyalgia have a shorter attention span and process information at a slower pace than do women with rheumatoid arthritis or those in good health, a study reports.
According to its investigators, these deficits may be a direct result of the increased sensitivity of neural circuits responsible for pain processing, which are believed to be involved in fibromyalgia’s onset.
The study, “Attentional function in fibromyalgia and rheumatoid arthritis,” was published in the journal PLOS One.
Fibromyalgia is a complex disorder characterized by widespread muscle pain, fatigue, sleep problems, depression, and anxiety. Cognitive issues, including lack of attention, forgetfulness, and mental slowness, are also frequent, with studies indicating they might be found in up to 90% of people with fibromyalgia.
Rheumatoid arthritis (RA) is an autoimmune disease that mainly affects the joints, causing pain, stiffness, and swelling. Similar to fibromyalgia, RA may also be associated with cognitive issues, with existing research pointing to deficits in attention, memory, and verbal function.
Few studies, however, have compared cognition in people with fibromyalgia or RA, and those that have are limited by small numbers of participants.
Researchers at the University of Jaén in Spain and a colleague in Austria conducted a study comparing cognitive skills in 56 women with fibromyalgia, 41 with RA, and 50 healthy women serving as controls. All were between the ages of 30 and 65.
These women completed the Attentional Network Test–Interaction (ANT-I), a cognitive test designed to evaluate three domains of attentional performance: alertness, cuing, and congruency.
During the test, women had to look at a row of three faces on a computer screen and indicate the gaze direction (right or left) of the central face. Alertness consisted of a given (or not given) short tone before the faces were displayed on the screen, cuing by placing or not placing an asterisk near one of the faces — either the target or a different one — and congruency (executive control) by varying the gaze direction of the faces left and right of the target. (Executive control refers to processes that control behavior such as planning, organizing, and paying attention.)
Test performance was based on reaction time — the time participants took to give an answer — coupled with the errors made on each trial.
Statistical analyses were then used to compare performance among these three groups.
Pre-test evaluations of clinical records, and responses in interviews and through questionnaires given all participants showed that women with fibromyalgia had more pain, and higher (worse) anxiety, depression, fatigue, and insomnia levels than those with rheumatoid arthritis and controls.
ANT-I results showed fibromyalgia patients had the longest reaction time, meaning they took longer to give a final answer than did the others, and they made more errors.
Test results for women with RA were similar to the control group in both reaction times and numbers of errors.
These differences were observed in all test variations, suggesting that fibromyalgia patients seem to have an overall attention deficit, rather than impairments in specific domains. Co-existing psychiatric conditions (depression and anxiety disorders) and medication use — antidepressants, anxiolytics, non-opioid analgesics and opiates — had no significant effect on reaction times or numbers of errors.
Differences evident in attentional performance between women with fibromyalgia and those RA might be the result of the different disease mechanisms at play in each disorder, the scientists suggested. Specifically, in the case of fibromyalgia, the excessive sensitivity and activity of brain circuits responsible for pain processing may limit the resources needed for attention and information processing.
“In summary, the study suggests of a more general deficit in attention and speed of information processing in [fibromyalgia], rather than specific impairments in the domains of alerting, orienting, and executive control,” they wrote.