Feature: ACS may induce post-traumatic stress
“Cardiologists have been on the cutting edge and early adopters of what’s become well known now, that the mind and the body are one,” said Donald Edmondson, PhD, of the Center for Behavioral Cardiovascular Health at Columbia University Medical Center in New York City. “They were very quick to understand the implications of depression after a heart attack.”
Most people, including many physicians, view PTSD as a disorder of veterans and sexual assault victims who have been exposed to a traumatic event. But the occurrence of ACS can be traumatic for patients as well. Improvements in survival after STEMI have led to more patients who may be living with ACS-induced PTSD.
“Cardiologists see what may seem routine to them,” Edmondson said. But patients may perceive an event such as MI as life-threatening, which may have a long-lasting psychological impact.
Most studies evaluating the prevalence and risk associated with PTSD in ACS patients have been small and marginally powered for answering questions about outcomes. To better understand the prevalence of ACS-induced PTSD and its association with recurrent cardiac events and mortality, Edmondson and colleagues designed a meta-analysis based on 24 observational cohort studies. Their findings were published online June 20 in PLos One.
The authors identified studies in Ovid MEDLINE, PsycINFO and Scopus published between 1948 and 2011 that assessed PTSD and referred to ACS (STEMI, NSTEMI and unstable angina) with the event occurring at least one month prior. The timing was important because while an event like STEMI is traumatic initially, after a month the patient’s distress should diminish, Edmondson explained. For the analysis, the researchers extracted estimates of prevalence of PTSD as well as other data.
Using a random effects model, they found an aggregated prevalence estimate of 12 percent of clinically significant symptoms of ACS-induced PTSD. Younger age was associated with greater prevalence. From the three prospective studies with findings on the association of PTSD and clinical outcomes, they calculated that having PTSD symptoms doubled the risk of mortality and recurrent cardiac events in ACS patients.
“Cardiologists have been reasonable, conservative and smart not to take any one of those studies too seriously,” Edmondson said, referring to the individual studies. “But by putting these studies together we can now say that about one in eight of your patients is going to develop clinically significant PTSD symptoms due to the heart attack.”
Edmondson said that a primary goal of their research is to raise awareness in the cardiology community that PTSD exists in the ACS patient population and is related to a doubling of risk of mortality and future cardiac events. But they also want to give physicians and patients a language to create a dialog about the symptoms and treatments.
“When patients don’t know that PTSD is a possible outcome of heart attacks and doctors don’t know that PTSD is a possible outcome of heart attacks, then how is the patient to know that it is abnormal for them a month later to still not think about the event, to get anxious when they think about it and have nightmares about it. They need to know that it (PTSD) is fairly common and there are treatments for it that work,” he said.
The researchers wrote that to date no studies have sufficiently explained the mechanisms or effect modifiers for the link between ACS-induced PTSD and adverse clinical outcomes nor have there been many studies on ACS-induced PTSD treatments. Edmondson recommended that a large randomized clinical trial be conducted to determine if screening of ACS patients for PTSD would be beneficial. But in the meantime, he proposed that cardiologists be willing to broach the subject with their patients.
Edmondson cited as a model the growing awareness of the prevalence of depression in ACS patients and that it leads to adverse outcomes. But while depression can be treated in these patients, he said it has yet to be shown definitively that treatment can reduce the risk.
“We hope that by detecting and treating PTSD due to heart attacks that we will be able to decrease future events,” he said. If that can be supported by evidence, then treatment may provide a pathway for better outcomes and the associated cost savings.
“We know we can improve quality of life and treat PTSD,” Edmondson said. “We hope we can also decrease secondary risk and health system expenditures.”