Persistent sleep disturbances after mild traumatic brain injury: A prospective multimodal assessment with actigraphy and hormonal biomarkers.

Introduction: Sleep disturbance is among the most frequent and disabling persistent post-concussive symptoms (PPCS) following mild traumatic brain injury (mTBI). However, the relationship between subjective complaints, actigraphic parameters, and neurohormonal markers remains poorly characterized. Research question: To determine the frequency, severity, and physiological correlates of sleep disturbance after mTBI, and to identify early objective predictors of persistent symptoms at three months. Material and methods: A prospective study including 51 patients with mTBI and 39 age- and sex-matched controls. Sleep was assessed at 1 week and 3 months using the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), 7-day wrist actigraphy (a wearable motion sensor to continuously monitor sleep-wake cycles), and plasma/salivary melatonin and orexin A/B levels. Group comparisons and within-subject changes were analyzed using parametric or non-parametric tests; correlations were assessed using Spearman's ρ. Results: At 1 week, 73.9% of patients met criteria for subjective sleep disturbance, with 48.6% remaining symptomatic at 3 months. Compared with controls, mTBI patients showed reduced sleep efficiency and increased wake after sleep onset. Higher ESS and PSQI scores correlated with longer sleep latency and more awakenings (ρ = 0.37-0.47; p < 0.05). Evening orexin A levels were elevated in symptomatic patients (p = 0.048). Shorter minimal sleep latency was the only independent predictor of persistent disturbance. Discussion and conclusion: Sleep disturbances after mTBI are common and partly reflected in objective alterations of sleep continuity. Early actigraphic evidence of hyperarousal may predict persistent symptoms. These findings support multimodal assessment to identify individuals at risk for chronic post-traumatic sleep disturbance.