Post-traumatic stress disorder (PTSD) is an anxiety disorder that is triggered by memories of a traumatic event. Building on research from the late 1990s, researchers at the Harvard School of Public Health have discovered a new aspect of PTSD: it may increase the risk of heart disease.

Triggering Traumatic Memories

PTSD can occur following the trauma of military combat, as well as natural disasters, terrorist attacks, and physical or sexual abuse. The disorder’s many symptoms may include flashbacks, emotional deadening, arousal symptoms such as anger and difficulty sleeping, and physiological reactions such as increased blood pressure, rapid heartbeat and breathing, and muscle tension. These symptoms typically appear within three months of the event, but in some cases they take years to surface.

In the brain, PTSD affects the amygdala and hippocampus, which regulate components of cognition. The amygdala, an almond-shaped structure located deep within the brain, governs the expression of emotions and the detection of potentially threatening stimuli. The hippocampus encodes emotional events and provides context for responses to fear. During these events, the amygdala and hippocampus communicate with each other.

PTSD Symptoms Increase Risk

The Harvard study, published in the January Archives of General Psychiatry, examined data from the Veterans Administration Normative Aging Study, a long-term research project that tracks the health of military veterans in the Boston area. Laura Kubzansky, who studies psychological factors that may be involved in the etiology of heart disease, and her colleagues analyzed the responses of male World War II and Korean War veterans to questionnaires measuring PTSD symptoms. Topics included sleep difficulties, nightmares, and disturbing memories of traumatic events.

One questionnaire was administered in 1986, the other in 1990. Some of the veterans answered only one questionnaire, although many responded to both. On average, the men were in their 60s when they answered either questionnaire. 

In the years since completing the surveys, the veterans with stronger PTSD symptoms suffered higher rates of coronary heart disease, suggesting that “prolonged stress and significant levels of PTSD symptoms may increase the risk of coronary heart disease in older male veterans,” Kubzansky writes.