Clinicians have long speculated that poor sleep may be a mechanism involved in the higher risk of further cardiac events or death among those with post-traumatic stress disorder following a heart attack, but the association between PTSD and sleep after a heart event has been unknown. Recent data from Columbia University Medical Center researchers have shown that symptoms of PTSD after a heart attack are relatively common. One in 8 heart attack survivors suffer PTSD and that survivors with PTSD have a doubled risk of having another cardiac event or of dying within one to three years, compared with survivors without PTSD.
A paper published in the current issue of Annals of Behavioral Medicine, by Jonathan A. Shaffer, PhD, and colleagues at Columbia’s Center for Behavioral Cardiovascular Health, reports on an analysis of the association of PTSD and sleep in nearly 200 patients who had experienced a heart attack within the previous month, recruited from NewYork-Presbyterian Hospital/Columbia University Medical Center. The study—the first of its kind—found that PTSD following a heart attack is associated with poor sleep.
The results showed that the more heart attack-induced PTSD symptoms patients reported, the worse their overall self-reported sleep was in the month following their heart attack. Greater PTSD symptoms following a heart attack were associated with worse sleep quality, shorter sleep duration, more sleep disturbances, use of sleeping medications, and daytime dysfunction due to poor sleep the night before.
The data also showed that people with poor sleep following a heart attack were more likely to be female and to have higher body mass index and more symptoms of depression; they were less likely to be Hispanic.
Dr. Shaffer and colleagues hypothesize that the strong association between heart attack-induced PTSD and sleep may be due to the fact that disturbed sleep is a standard characteristic of PTSD. Results of recent treatment studies for PTSD and sleep disturbance suggest that the two conditions should be viewed as comorbid, rather than one being merely a symptom of the other.
In addition, dysregulation of the autonomic nervous system (the part of the nervous system responsible for regulating involuntary bodily functions, such as breathing, heartbeat, and digestive processes), which is associated with both PTSD and disrupted sleep, may represent a common mechanism underlying their association.
Further research is needed to better understand the associations of PTSD due to heart attack, poor sleep, and risk for future heart attacks.