THURSDAY, Dec. 11, 2008 (HealthDay News) -- Too much togetherness can raise women's heart risks, a new Japanese study finds.
Those living in multigenerational households that include children and grandparents were two to three times more likely to be diagnosed with serious heart disease than those living with just a spouse, a group led by researchers at Osaka University reported in the Dec. 11 online issue of Heart.
No similar increase for men in such households was seen in the study, which followed almost 91,000 family members for as long as 14 years.
While none of the participants had serious diseases like cancer, heart ailments or stroke when the study began, the researchers found that when the monitoring period ended in 2004, 671 had been diagnosed with coronary artery disease and 339 had died of coronary heart disease.
Multigenerational living did not increase harmful habits such as smoking and heavy drinking, the researchers said. For example, only 2.7 percent of the women living with a spouse, child and parent smoked, compared to 6.3 percent of those living only with a spouse.
Instead, it appears to be the stress created because Japanese women are required not only to fulfill their duties as housekeepers but also go out to work, the researchers said.
"More Japanese middle-aged women are employed full time than ever before," they wrote. "Yet the burden of domestic labor [including child care and care of aging relatives] continues to fall primarily on women, even as their workforce participation has increased."
It's a familiar pattern in America, said Dr. Suzanne Steinbaum, director of women and heart disease at Lenox Hill Hospital in New York City. "I talk about this all the time," she added. "Women are becoming more educated and are more and more in the work force, yet culturally they still are the caretakers of the family."
Americans also might be moving more toward the Japanese pattern of several generations living in the same household, Steinbaum said. Since women not only earn money on the job but also look after an extended family, "there is an enormous amount of stress and pressure required to do all these things," she said.
Today's dire economic situation appears to be adding to the stress, as families squeeze together to reduce costs, Steinbaum said.
"Perhaps we are becoming more like the Japanese, a more multigenerational society, and in that case ,it is very important that we don't put all the burden on women," she added.
The existing American concept of family might have to be changed, Steinbaum noted. "Roles need to be redefined," she said. "There needs to be either a return to tradition or there needs to be a better sharing of responsibilities."
The main conclusion of the report appears to be accurate, said Dr. Lori Mosca, a physician scientist at New York Presbyterian Hospital. "Certainly, caring for others can increase the risk of heart disease," she added.
But caution is needed about reaching any final conclusions, Mosca said. "It is a small study, and it did not adjust for socioeconomic status," she said. "Many women living in multiple generations in the house are from lower-income families, and that increases the risk of heart disease."
Still, the risk of heart disease for such women is real, Mosca added. "We should incorporate this potential risk factor into our screening, and refer women for support services when needed," she said.
Learn about women and heart disease from the American Heart Association.