Pain, executive functioning, and affect in patients with rheumatoid arthritis.

OBJECTIVES: Rheumatoid arthritis (RA) is a chronic inflammatory disease resulting in substantial pain. The physical and emotional effects of RA are well known, but little attention has been given to the potential cognitive effects of RA pain, although intact executive functioning in patients with chronic illness is crucial for the successful completion of many daily activities. We examined the relationship between pain and executive functioning in patients with RA, and also considered the influence of positive and negative affect in the relationship between pain and executive functioning.
METHODS: A sample of 157 adults with RA completed measures of pain and positive and negative affect and were tested for working memory and selective attention using the Letter Number Sequencing subtest from the Wechsler Adult Intelligence Scale-Third Edition and the Stroop Color Word Test tests, respectively.
RESULTS: Consistent with prior research, pain was inversely related to executive functioning, with higher pain levels associated with poorer performance on executive functioning tasks. This relationship was not moderated or mediated by negative affect; however, positive affect moderated the relationship between pain and executive functioning. For patients high in positive affect there was a significant inverse relationship between pain and executive functioning, whereas there was no such relationship for patients low in positive affect. DISCUSSION: These findings are discussed in the context of cognitive research on the effects of positive affect on executive functioning and functional neuroanatomical research suggesting neurocognitive mechanisms for such moderation.