Sleep disturbance as a predictor of affective functioning and symptom severity among individuals with PTSD: An ecological momentary assessment study

- Poor sleep quality and efficiency predicted increased daytime PTSD symptoms.
- Poor sleep quality and efficiency predicted increased daytime negative affect.
- Poor sleep quality predicted decreased daytime positive affect.
- The effect of sleep quality on PTSD symptoms was mediated by negative affect.
- Daytime PTSD symptoms only predicted nightmares.

Recent research has highlighted the etiological role of sleep disturbance in posttraumatic stress disorder (PTSD); however it is currently unknown how daily changes in sleep are associated with next-day PTSD symptoms. Furthermore, sleep is critical for maintaining appropriate affect, leading some to hypothesize that affective dysfunction may account for the link between sleep disturbances and PTSD symptoms. Thus, the current study tested the relationship between sleep disturbances, affective valence, and PTSD symptoms utilizing an ecological momentary assessment (EMA) design among individuals with PTSD (n=30) who participated in 4 EMA-based assessments daily over 8 days. Multilevel modeling indicated that, after accounting for prior evening's PTSD symptoms, poor sleep quality and reduced sleep efficiency were associated with increased PTSD symptoms and negative affect. Furthermore, results supported the indirect effect of poor sleep quality on elevated PTSD symptoms through increased negative affect in the morning. Findings add to the body of research demonstrating the negative impact of poor sleep for individuals with PTSD by indicating that daily variations in sleep can affect next-day PTSD symptoms, and identifying negative affect as a mechanism of this relationship.