Sleep reactivity as a vulnerability to posttraumatic stress disorder: Identifying patients at risk of acute insomnia within the immediate aftermath of trauma

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) 2025 APA, all rights reserved).

Figure 1. Interaction Between Trait Sleep Reactivity and Insomnia Symptoms One Month After Trauma on Future PTSD Symptoms Two Months After Trauma

Note. Trauma patients were recruited during hospitalization (Time 1 [T1]) and prospectively followed to one-month (Time 2 [T2]) and two-month (Time 3 [T3]) post-trauma follow-up. Trait sleep reactivity = Ford Insomnia Response to Stress Test (T1) score ≥ 20; Insomnia symptoms = Insomnia Severity Index sum score (T2); PTSD Symptoms = PTSD Scale for DSM-5 sum score (T3).

Figure 2. Highly Sleep Reactive Trauma Patients Report Higher Rates of Acute Insomnia and PTSD After Trauma

Note. Rates of acute insomnia (A) and PTSD (B) one- and two-months post trauma based on trait sleep reactivity as assessed during hospitalization. Data are from participants with no lifetime diagnosis of insomnia disorder prior to the trauma, as confirmed by self-report and electronic medical records. Chi-square analyses indicated that insomnia and PTSD rates significantly differed across groups (ps <0.05). Trait sleep reactivity = Ford Insomnia Response to Stress Test score ≥ 20; Acute insomnia = Insomnia Severity Index score ≥ 15; PTSD = PTSD Checklist for DSM-5 score ≥ 31.

Figure 3. Acute Insomnia One Month After Trauma Predicts More Severe PTSD Two Months After Trauma Among Patients with High Sleep Reactivity

Note. Sleep reactivity strengthens the relationship between post trauma insomnia and future PTSD (β = 0.62, SE = 0.53, p = 0.025). Trait sleep reactivity = Ford Insomnia Response to Stress Test score ≥ 20 assessed during hospitalization; Insomnia = Insomnia Severity Index sum score; PTSD = PTSD Checklist for DSM-5 sum score. Model accounts for lifetime diagnosis of insomnia prior to trauma assessed via self-report and electronic medical records, clinically significant acute stress symptoms assessed one month post trauma, sex, current sleep medication usage, and days since trauma.