HIGHER SLEEP EFFICIENCY IMPROVES ATTENTION AND PROCESSING SPEED IN PATIENTS WITH SEVERE PAIN AND IMPLANTABLE CARDIOVERTER DEFIBRILLATORS

Patients with implantable cardioverter defibrillators (ICDs) commonly experience sleep disruption, and research suggests they may perceive physical pain more strongly than individuals without ICDs. Prior work points to associations between objective (i.e., actigraphic) sleep and cognitive performance in patients with ICDs, but whether pain affects associations between measures of sleep fragmentation (e.g., sleep efficiency, SE) and cognition is unknown. The goal of the present study was to examine the independent and interactive associations between SE and pain on cognition in patients with ICDs. Thirty-seven patients with ICDs (Mage=60.0, SD=12.4) and self-reported sleep disturbance completed 14 days of actigraphy. Sleep efficiency (SE) was computed as the total sleep time/time in bed x 100%. Patients completed the pain section of the Short Form 36 Health Survey (SF36), with lower scores indicating worse pain. Patients also completed computerized tasks measuring executive functioning (i.e., letter series, n-back task), and attention/processing speed (i.e., simple reaction time; symbol digit modality task, SDMT). Multiple linear regressions examined whether SE independently predicted or interacted with pain ratings to predict performance across cognitive tasks. SE interacted with pain ratings to predict SDMT performance (B=-.0001, SE=.00, p=.04), accounting for 12% of the unique variance in performance. In patients reporting more severe pain, higher SE was associated with better SDMT performance (B=.004, SE=.002, p=.03). Similar patterns of association between SE and pain on SDMT were not observed in patients with average or low pain (ps>.05). SE and pain ratings did not independently predict SDMT performance (ps>.05). Performance on other cognitive tasks was not associated with any predictors (ps>.05). Better sleep efficiency may play an important role in improving attention/processing speed performance in patients with ICDs and perceived severe pain. Future research should examine whether interventions aimed at improving sleep fragmentation provide benefit to lower order cognition, particularly in patients with more severe pain. Project supported by: National Heart, Lung, and Blood Institute (R21HL087831,PI:McCrae), National Institute on Aging of the National Institutes of Health (K23AG049955,PI:Dzierzewski).