Abstract
OBJECTIVE: Insomnia within the immediate aftermath of trauma is a key risk factor for posttraumatic stress disorder (PTSD). However, it is unknown who is most at risk for insomnia after trauma, obstructing the ability to identify high-risk groups in need of early intervention. We examined whether individuals with high sleep reactivity-a trait vulnerability to sleep disturbance after stress-are vulnerable to posttrauma insomnia and subsequent PTSD. METHOD: We recruited 88 participants hospitalized in a Level I trauma center in Detroit, MI following traumatic injury (M(age) = 39.53 ± SD 14.31 years, 67.0% male, 67.0% Black, 47.7% income ≤$20,000). Patients reported trait sleep reactivity within 1 week of trauma (during hospitalization), posttrauma insomnia 1 month later (n = 61), and PTSD 2 months later (n = 59). RESULTS: Patients without a history of insomnia who had high sleep reactivity were twice as likely to report acute insomnia 1-month posttrauma (55.2% vs. 28.6%) and 4.1 times more likely to report PTSD 2-month posttrauma (45.5% vs. 11.1%). The pathogenicity of insomnia on future PTSD was stronger for patients with high sleep reactivity: among patients with insomnia 1-month posttrauma, those with high sleep reactivity reported more severe PTSD 2-month posttrauma (M(PTSD) = 29.94) than those with low reactivity (M(PTSD) = 9.84; g = 1.43; p = .002). CONCLUSIONS: These novel longitudinal findings indicate highly reactive sleepers are most vulnerable to acute insomnia immediately after trauma that confers future risk for clinically significant PTSD symptoms. (PsycInfo Database Record (c) 2026 APA, all rights reserved).