Researchers say there may be a link between the post-traumatic stress disorder (PTSD) and the cognitive impairment found in civilian workers who responded to the 2001 World Trade Center (WTC) terrorist attacks.

The study is the latest research into how PTSD can affect a person’s brain functions and potentially lead to certain forms of dementia.

cognitive impairment and ptsd

Past studies have developed potential links between PTSD and cognitive impairment in military veterans.

Researchers say their findings, published in an Alzheimer’s Association journal, may help identify people at higher risk for dementia as well as lead to earlier treatments for these conditions.

“It adds a little more to the puzzle,” Heather M. Snyder, Ph.D., the senior director of medical and scientific operations at the Alzheimer’s Association, told Healthline.

Read more: PTSD can last for years in people who witness traumas »

Looking at civilian workers

The researchers used the database from the World Trade Center Health Program overseen by the U.S. Centers for Disease Control and Prevention (CDC).

More than 33,000 people who responded to the September 11 terrorist attacks have registered for the program.

In this study, clinicians used the MoCA test battery to screen 818 civilians, such as construction workers, who helped with search, rescue, and cleanup efforts at the World Trade Center in New York.

The average age of those screened was 53 years. None of them were known to have suffered any serious head injuries.

Researchers said more than 12 percent (104 people) of those screened had test scores indicative of cognitive impairment. Another 1 percent (10 individuals) had scores suggesting possible dementia.

Researchers said PTSD and major depressive disorder (MDD) were associated with the cognitive impairment.

In addition, symptoms such as flashbacks and nightmares were also consistent with cognitive impairment.

The researchers said if the percentages in their study group were the same for the 33,000 enrollees in the CDC program, that would mean 3,700 to 5,300 individuals in that group would suffer from cognitive impairment. Another 240 to 810 people would have dementia.

Read more: PTSD linked to faster aging, earlier death »

Importance of the research

Snyder said unraveling the puzzle of Alzheimer’s and other dementia-related diseases is a complex undertaking.

Studying PTSD and its effects is one part of this research, and interest in this field is growing.

She said one of the important aspects of this latest study is that it was done on civilians as opposed to veterans or law enforcement officers.

Snyder said understanding the connection between PTSD and cognitive impairment could help doctors identify people at higher risk at an earlier stage.

“It really is an important question,” she said.

Snyder’s comments were echoed by others in the organization.

“This is a problem we must solve,” said Maria Carrillo, Ph.D., Alzheimer’s Association chief science officer, in a statement. “The silver lining in these troubling new findings is that they will help us better understand the relationship between PTSD, cognition, and dementia. More research is needed in this area. This is crucial so that we can provide better care for all individuals who experience PTSD.”