Cognitive complaints are associated with depression, fatigue, female sex, and pain catastrophizing in patients with chronic pain

Objective: To examine the relation between demographic, pain-related, psychosocial, affective, and treatment factors and complaints of cognitive dysfunction among patients with chronic pain. Design: Cross-sectional survey. Setting: A university hospital outpatient multidisciplinary chronic pain program. Participants: Chronic pain patients (N=222; 135 women, 87 men) completed a battery of psychometric questionnaires as part of an initial evaluation on referral to the program. Interventions: Not applicable. Main Outcome Measures: Cognitive impairment was assessed with items from the Brief Symptom Inventory; measures of depressive symptoms, pain intensity, posttraumatic stress disorder (PTSD), and pain catastrophizing were obtained from the Beck Depression Inventory (negative affect, negative self, somatic/physical function), McGill Pain Questionnaire, Modified Posttraumatic Chronic Pain Test, and Coping Strategies Questionnaire, respectively; and measures of subjective sleep disturbance, fatigue, opiate use, compensation/litigation status, pain location, and relevant demographic data were obtained from an open-ended questionnaire. Results: Correlational analysis indicated that female sex, pain intensity, PTSD symptoms, depressive symptoms, catastrophizing, pain location (neck), and fatigue were all positively related to cognitive complaints. Simultaneous regression analysis showed that all factors combined accounted for 52% of the variance in self-report of cognitive difficulties and that 6 variables had a significant unique contribution to the report of cognitive complaints in the following order of importance: depression-negative affect (beta = 28, P < .05), fatigue (beta = .17, P < .05), depression-somatic/physical function (beta = .16, P < .05), depression-negative self (beta = .14, P = .05), pain catastrophizing (beta = .12, P = .08), and female sex (beta = .12, P < .05). Conclusions: Complaints of cognitive impairment among chronic pain patients appear to be associated with multiple factors, with particular attention to depressive symptoms, fatigue, and catastrophizing. Our results also suggest that women with chronic pain are particularly vulnerable to cognitive dysfunction.