1026 Associations Between Physiological Arousal and Executive Function in Adults With Chronic Widespread Pain and Insomnia Complaints

Abstract

Introduction: Individuals with chronic widespread pain (CWP) commonly experience increased physiological arousal, insomnia symptoms, and cognitive disturbance. Higher arousal (as measured by heart rate variability, HRV) is associated with worse executive function in healthy adults, suggesting that hyperarousal selectively disrupts prefrontal cortical activity. However, the HRV/cognition relationship in CWP, the moderating impact of insomnia severity, as well as the components of executive function affected, are unclear. The present study assessed independent associations between HRV and components of executive functioning in patients with CWP and insomnia complaints, and evaluated whether these associations depend on insomnia severity. Methods: Forty-two adults (Mage=46.2, SD=13.7) with comorbid CWP and insomnia complaints (difficulty falling/staying asleep plus daytime dysfunction) underwent 5-minutes of Holter monitoring to assess resting HRV. The root mean standard deviation of successive normal to normal heartbeats (RMSDNN) was computed as the HRV index. Participants completed the Insomnia Severity Index (ISI). Participants also completed three computerized tasks measuring executive function: Stroop task (inhibition), Sternberg task (working memory), and the Balloon Analogue Risk Task (risk taking behavior). Multiple regressions examined whether RMSDNN independently predicted or interacted with ISI to predict cognition, controlling for age. Results: RMSDNN independently predicted Stroop performance, with higher RMSDNN (lower arousal) associated with lower interference scores (better inhibitory function), B=-.003, SE=.001, p=.029, Full Model R2=.31. RMSDNN and ISI did not independently predict or interact to predict Sternberg/ BART performance. Conclusion: In patients with CWP and insomnia symptoms, reduced physiological arousal was associated with better inhibition, and this did not depend on insomnia severity. Findings highlight the potential underlying role of hyperarousal in a specific component of executive disruption in CWP. Results suggest that treatments aimed at reducing physiological arousal in comorbid CWP and insomnia (e.g., relaxation, HRV biofeedback) may selectively improve inhibitory function. Findings warrant further consideration in larger samples and prospective analyses.