Traumatic experiences are common and linked to cardiovascular disease (CVD) risk, yet the mechanisms underlying these relationships is less well understood. Few studies have examined trauma exposure and its relation to autonomic influence over cardiac function, a potential pathway linking trauma exposure to CVD risk. Investigating autonomic influence over cardiac function during both wake and sleep is critical, given particular links of sleep autonomic function to cardiovascular health. Among midlife women, we tested whether trauma exposure would be related to lower high frequency heart rate variability (HF-HRV), an index of vagal influence over cardiac function, during wake and sleep. Three hundred and one nonsmoking midlife women completed physical measures, a 24-hr electrocardiogram, actigraphy sleep measurement, and questionnaires about trauma (Brief Trauma Questionnaire), childhood abuse (Child Trauma Questionnaire [CTQ]), mood, demographics, and medical/psychiatric history. Relations between trauma and HF-HRV were assessed in linear mixed effects models adjusting for covariates (age, race, education, body mass index, blood pressure, psychiatric history, medication use, sleep, mood, childhood abuse history). Results indicated that most women had experienced trauma. Any trauma exposure as well as a greater number of traumatic experiences were associated with lower HF-HRV during wake and particularly during sleep. Relations were not accounted for by covariates. Among midlife women, trauma exposure was related to lower HF-HRV during wake and sleep. Trauma may have an important impact on vagal influence over the heart, particularly during sleep. Decreased vagal influence over cardiac function may be a key mechanism by which trauma is associated with CVD risk.

Objectives 
Whereas some work links trauma exposure to poor subjective sleep quality, studies largely rely upon limited trauma measures and self-reported sleep at one time point. It is unknown whether trauma is related to persistent poor sleep, whether associations differ based on childhood versus adulthood trauma, and whether trauma exposure is related to poorer objectively assessed sleep. We tested whether childhood or adult trauma associated with persistent poor objectively and subjectively measured sleep at two time points in midlife women.
Methods 
One hundred sixty-seven women aged 40-60 at baseline were assessed twice 5 years apart. At baseline, women reported childhood trauma (Child Trauma Questionnaire), adult trauma (Brief Trauma Questionnaire), demographics, depressive symptoms, apnea symptoms, and medical history, and provided physical measures. At both visits, women completed 3 days of actigraphy (total sleep time [TST], wake after sleep onset [WASO]) and reported sleep quality (Pittsburgh Sleep Quality Index). Relations of childhood and adult trauma exposure, respectively, with persistent poor sleep at both baseline and follow-up visits (TST [<6 hours], WASO [>30 minutes], Pittsburgh Sleep Quality Index [>5]) were assessed in logistic regression models, adjusted for age, race/ethnicity, education, body mass index, sleep medications, nightshift work, apnea, depressive symptoms, vasomotor symptoms, and alcohol use.
Results 
Childhood trauma was related to persistent high WASO (odds ratio [95% confidence interval] = 2.16 [1.04-4.50], P = 0.039, multivariable). Adult trauma was related to persistent poor sleep quality (odds ratio [95% confidence interval] = 2.29 [1.07-4.93], P = 0.034, multivariable). Trauma was unrelated to persistent short TST.
Conclusions 
Childhood and adult trauma, respectively, were related to persistent poor objective sleep continuity and subjective sleep quality in midlife women, independent of risk factors.