WEDNESDAY, April 11 (HealthDay News) -- The spouses of cancer patients are at increased risk of heart disease and stroke, a new study suggests.

Researchers said the explanation might be that stress takes a toll on the health of caregivers.

Using the national Swedish cancer registry and the Swedish inpatient registry, researchers found that risk for heart disease and stroke increased by 13 to 29 percent in people whose partner had cancer.

"Our study shows that preventive efforts aimed at reducing psychological stress and negative risk factors are important for people whose life partner has got cancer," Jianguang Ji, a researcher from the Centre for Primary Healthcare Research in Malmo, Sweden, said in a university news release. "Previous studies have shown that preventive work can considerably reduce stress and anxiety in close relatives of patients."

The study authors considered another explanation for the higher heart risks -- spouses may share lifestyle risk factors, such as tobacco and alcohol use as well as poor diet and lack of exercise. But the researchers found that spouses' added risk for heart disease was only slightly increased by about 3 to 5 percent right before their partner became sick.

The study is published in the March 13 issue of Circulation.

While the study uncovered an association between caring for a spouse with cancer and heart risks, it did not prove a cause-and-effect relationship.

More information

The U.S. National Cancer Institute has more about family caregivers for patients with cancer.