Subjective sensory hypersensitivity in chronic acquired brain injury patients: the relationships with insomnia, hyperarousal and perceived stress.

Sensory hypersensitivity following acquired brain injury (ABI) is frequently reported and affects well-being, yet remains poorly understood. Research in neurotypical individuals suggests a link between hypersensitivity, insomnia, hyperarousal and perceived stress. This study examined the relationship between sensory sensitivity and insomnia in ABI patients and whether hyperarousal and/or perceived stress mediates this relationship. In an online cross-sectional cohort study among 188 chronic ABI patients of University Medical Centre Utrecht and 61 neurotypical controls, sensory hypersensitivity was measured using the Multi-Modal Evaluation of Sensory Sensitivity, insomnia using the Insomnia Severity Index, hyperarousal using the Hyperarousal Scale, and perceived stress using the Perceived Stress Scale. Associations were examined using multiple regression and mediation analyses with bootstrapping. The results confirmed that sensory hypersensitivity was frequent (66%) and persistent following ABI, mainly in visual and auditory modalities. Increased sensory hypersensitivity was related to higher severity of insomnia in ABI patients. This relationship was partially mediated by hyperarousal and perceived stress. Hyperarousal and perceived stress may underlie the link between sensory hypersensitivity and insomnia, although the direction of these effects remains unclear.