The more traumatic events a woman experiences during her lifetime, the more likely she is to become obese, researchers reported at the American Heart Association’s Scientific Sessions this week.

Michelle A. Albert, MD, MPH, and colleagues analyzed the relationship between obesity and major life events in a cohort of 21,904 middle-aged and older women, focusing on those with the highest obesity prevalence, according to a release from the American Heart Association (AHA). They split stressful events into two categories: traumatic life events such as the death of a child, which could occur at any time in life, and negative events over the past five years like unemployment. In both instances, higher records of stressful events translated to higher numbers on the scale.

“Little is known about how negative and traumatic life events affect obesity in women,” Albert said in the AHA release. “We know that stress affects behavior, including whether people under- or overeat, as well as neuro-hormonal activity by in part increasing cortisol production, which is related to weight gain.”

Twenty-three percent of the women studied in this trial were obese, Albert reported. In the general U.S. population, 70 percent of women are either overweight or obese, though extra weight is considered a preventable risk factor for cardiovascular disease. According to the release, older, heavier women are especially at risk for adverse heart events since women tend to live longer than men.

“This is important work because women are living longer and are more at risk for chronic illnesses, such as cardiovascular disease,” Albert said. “The potential public health impact is large, as obesity is related to increased risks of heart attack, stroke, diabetes and cancer, and contributes to spiraling healthcare costs.”

Albert and co-authors found that women who reported more than one traumatic life event compared with none at all saw an 11 percent increased risk of developing obesity. The same was true for negative life events, with women who said they’d experienced four or more negative events over the past five years seeing a 36 percent increased risk of obesity.

“Our findings suggest that psychological stress in the form of negative and traumatic life events might represent an important risk factor for weight changes and, therefore, we should consider including assessment and treatment of psychosocial stress in approaches to weight management,” Albert said.