Comparison of the Cognitive Performance Between Healthy Controls, Rheumatoid Arthritis and Fibromyalgia Patients without Depression

Abstract

The purpose of this study was to assess the cognitive performance in fibromyalgia(FM) patients without depression and to compare it with rheumatoid arthritis(RA) patients and 15 healthy controls. Material and Method: 16 FM and 15 RA patients participated in the present study. All participants completed several psychological measures. The cognitive functions measured were global attention/working memory, language, visual and verbal memory, visuo-spatial processes and executive functions. Pain severity, fatigue and sleep quality in FM patients were evaluated by the visual analog scale(VAS)(0-10). Other symptoms of FM were evaluated using the Fibromyalgia Impact Questionnaire(FIQ). Results: FM and RA patients performed poorly on most cognitive measurements compared with healthy controls. The performance of the FM patients was similar to that of the RA patients on most cognitive measures. However, FM patients performed more poorly than RA patients on measures of executive functions(p<0,05). Self reported pain correlated with two cognitive measures: global attention/working memory and executive functions(r=0.51, p<0.05 and r=0,68, p<0,05 respectively). The fatigue correlated only with executive functions(r=0,51, p<0,05). Discussion: Our results indicated that FM patients without depression had poor cognitive performance on complex cognitive tasks. In addition, the present results show that some variables such as pain and fatigue were significantly related to cognitive performance.