VCU news

By Lorraine Cichowski and Kenneth Kendler

RICHMOND, Va. – Researchers at Virginia Commonwealth University have documented the interrelationship of the personality trait of neuroticism and stressful life events in predicting episodes of major depression.

The study, published in the American Journal of Psychiatry, found that neuroticism increases the risk of major depression and that neuroticism also makes people more sensitive to stressful events that may cause depression.

Major depression is the most serious form of depression. It affects an estimated 17 million people in the United States annually and can be marked by persistent sadness, apathy, a feeling of worthlessness, irritability and recurring thoughts of death or suicide.

"We wanted to get a fine-grained look at how vulnerability and stress inter-relate in the development of depression," said psychiatric geneticist Kenneth S. Kendler, M.D., professor of psychiatry and director of the Virginia Institute for Psychiatric and Behavioral Genetics at VCU. "We clearly showed that, as your level of vulnerability goes up, the impact of stress becomes greater and greater. So, as we have suspected, a key part of the vulnerability to depression is high levels of sensitivity to the effects of stressful events."

Kendler was the lead author on the study, which assessed 14 symptoms for major depression in 7,517 male and female twins registered with the Mid-Atlantic Twin Registry at VCU. The study sought to evaluate the impact of the personality trait of neuroticism, gender and adversity on the risk of depression.

It found that at every level of stress exposure, neuroticism increased the risk of major depression. Higher levels of neuroticism for both men and women predicted an increased risk for major depression, particularly in situations where the individual felt a high-level of long-term stress or threat, such as a personal assault, divorce, major financial problem or serious illness.  At every level of neuroticism and adversity, the risk of depression was higher in women than men. However, high female-to-male ratios for major depression were found only with low levels of adversity.

Neuroticism was measured by a 12-item scale that included such questions as: "Are you the type of person who is easily hurt?" and "Are you the type of person who is a worrier?"

The study was supported by grants from the National Institute of Mental Health, the National Institute on Alcohol Abuse and Alcoholism and the National Institute on Drug Abuse.