Children of divorced parents may have shorter life spans than those whose families remain intact, a new study suggests.
In the 70-year study of more than 1,200 men and women, those who were younger than 21 when their parents divorced died an average of 4 1/2 years earlier than those whose parents had not divorced.
Overall, people who were young when their parents divorced were 44 percent more likely to have died by the end of the study than people whose parents stayed married, according to the report, published today in the American Journal of Public Health.
The researchers, led by Joseph Schwartz of the State University of New York at Stony Brook, speculated that parental divorce causes increased stress in children that can lead to unhealthy behaviors -- such as substance abuse or following a poor diet -- when they grow up.
Divorce also could adversely affect children's social development and coping skills, resulting in a shorter life span, Mr. Schwartz said.
"This adds to the evidence that social relationships, even those that occur at a young age, have a powerful impact on health," said Dr. Thomas Campbell, an associate professor of family medicine and psychiatry at the University of Rochester in New York.
The researchers studied data from white, middle-class people born in California around 1910 who had participated in the Terman Life Cycle Study. That study followed people starting about age 11 and ending about 70 years later.
The new study was designed to determine what childhood traits in these people may have predicted their life expectancies.
According to the report, men who were children when their parents divorced lived an average of 75 years, compared to 80 years for men whose parents stayed married. Women who were children of divorced parents lived an average of 81 years, compared to 86 years for women of married parents.
Parental divorce may not only cause children to grow up to have bad health habits, it also may affect children's psychological health, Dr. Campbell suggested. This could result in increased stress and depression -- both of which are known to affect long-term health, the University of Rochester researcher said.
But the research should not change the way children of divorced parents are treated, he cautioned.
"Doctors should be aware of these issues," Dr. Campbell said. "But in terms of individual patients, most of these children as they grow are very resilient and are not adversely affected by divorce."
Lewis Kuller, an epidemiologist at the University of Pittsburgh, warned that studies using data originally gathered for different research purposes, as was the case in this study, should be viewed cautiously.
Yet the finding that "having divorced parents is not particularly good for your health is probably not surprising," he wrote in an editorial accompanying the study.