While women are twice as likely as men to experience post-traumatic stress disorder (PTSD), there’s historically been less research focused on the effects of PTSD on women’s health.
Two researchers at the University of Colorado Anschutz School of Medicine are working to reverse that trend. Emily Larson, PhD, a postdoctoral fellow in the Divisions of Geriatric Medicine and Renal Diseases and Hypertension, and Kerrie Moreau, PhD, a professor in the Division of Geriatric Medicine and research health scientist at the Rocky Mountain Regional VA Center, are conducting two studies that focus on the convergence of mental and physical health.
The goal of the research is to understand how PTSD-related nightmares impact cardiovascular health in women. The School of Medicine researchers are using a digital therapeutic sleep intervention called NightWare to investigate whether it can improve sleep and cardiovascular health.
Larson’s study includes two groups of premenopausal women, half of whom suffer from PTSD-related nightmares, and the other half who report no nightmares. She will also be monitoring kidney health in addition to heart health. Moreau chose to study women veterans, after concluding another study of non-veterans.
“We know sleep is very important for overall health, and that having poor sleep can increase a person’s cardiovascular disease risk. You can think of PTSD as an accelerated aging condition,” Moreau says. “If we can prove our concept that sleep quality improves with this digital therapeutic intervention, then we will be conducting a larger clinical trial with a longer treatment period.”
The link between sleep and heart health
Post-traumatic stress disorder has been linked to various cardiovascular conditions and sleep issues. It also increases the risk for Alzheimer’s disease and related dementia, and is associated with faster cognitive decline.
“Epidemiological studies have shown that people with PTSD have an increased risk of various cardiovascular diseases and that’s what prompted the study,” Larson says. “Oftentimes people with PTSD will also have increased arterial stiffness and vascular endothelial dysfunction, two functional markers of vascular aging.”
Sleep is a restorative time crucial to the regulation of hormones and autonomic nervous system activity, which in turn is important for regulating oxidative stress and inflammation. People who have PTSD can have chronic sleep disturbances and live in a state of elevated stress, contributing to disruptions of those pathways. It can also alter stress hormone signaling and increase arousal responses and sympathetic nervous system activity that, apart from the sleep disturbances, may contribute to adverse effects on cardiovascular health.
To understand the severity and frequency of nightmares experienced by research participants, Larson and Moreau’s research relies on survey-based screening tools such as the Nightmare Disorder Index. Study participants are also given at-home sleep monitors to look at sleep architecture including REM sleep.
The NightWare technology is a prescription-only device consisting of an Apple Watch and iPhone that work together through an application. Participants wear the watch every night, and it monitors body position, heart rate and movement to try to distinguish on an individual level what is normal sleep versus when someone might be going into a nightmare.
If vital signs indicate a participant crossing the threshold into a nightmare, the watch tries to disrupt the nightmare without waking the individual through a series of vibrations.
Half of study participants with PTSD-related nightmares wear a non-functioning device as a placebo, and the other half receives the intervention therapy. At the end of eight weeks, their cardiovascular function is measured and compared to function before the intervention.
Closing the research ‘gap’
“When we are doing lifespan research to try to understand the biology of aging, there are a lot of environmental stressors that could be impacting health, whether it be trauma exposure, childhood experiences, life adversity, a complicated pregnancy, or intergenerational trauma,” Moreau says. “We are trying to understand this from a whole health standpoint, and that includes life exposures that we’ve ignored for far too long.”
Moreau’s appointment at the VA led her to develop a niche of research. She started to put together proposals to study the impact of PTSD on the cardiovascular aging process in women veterans. Her curiosity was driven by seeing variations in how patients experienced the aging process and responded to treatments. The results of her first study, focused on non-veterans, are being tabulated.
Both Moreau and Larson are motivated to learn more about a population of women that experience PTSD but have been largely left out of previous research into how the disorder affects health. Even in conversations with the public, the duo has found that most people still associate PTSD more heavily with men in combat than they do with women, who are more likely to develop PTSD following trauma, generally from a broader array of life adversities.
In 2024, Larson received an early career seed grant through the Ludeman Family Center for Women’s Health Research, which is funding her current study on premenopausal women.
In addition to financing her research on PTSD and heart and kidney health, the center’s grant provided her with early career training, speaking opportunities, and networking. Larson says she is grateful for the help she’s received in pursuing such an important avenue of research.
“Although PTSD impacts so many women and so disproportionately, there really isn’t a representation of that on the research side,” Larson says. “My project is trying to close that gap.”