"Growing evidence suggests that the quality and patterns of one's social relationships may be linked with a variety of health outcomes, including heart disease," says Dr. Thomas Kamarck, professor of psychology and Biological and Health Program Chair in the University of Pittsburgh Kenneth P. Dietrich School of Arts and Sciences.
Researchers observed the interactions of 281 middle-aged adults either married or in domestic partnerships over a four-day period. All were healthy and employed.
Subjects judged their interactions as positive or negative and researchers measured the thickness of their carotid arteries, finding a correlation between negativity and thicker arteries.
Lead study author Dr. Nataria Joseph of the VA Greater Los Angeles Healthcare System says that those with frequent negative interactions increase their risk of heart attack or stroke by eight percent.
She says the findings could not be rooted in other biological or social risk factors and did not depend on the frequency of partner interaction, although Joseph admits the study has limitations due to its short duration.
Although causality has not been proven, it is important to add that no inconsistencies were found concerning partners' age, sex, race or education level.
"What it does show," says Joseph, "is that health care providers should look at relationships as a point of assessment. They are likely to promote health or place health at risk."
In a study presented in March of this year at the American College of Cardiology conference, researchers at the New York University Langone Medical Center concluded that being married makes for a healthy heart, while divorce and widowhood could increase risk for cardiovascular disease.
"These findings certainly shouldn't drive people to get married, but it's important to know that decisions regarding who one is with, why, and why not may have important implications for vascular health," said lead author Carlos Alviar, cardiology fellow at New York University Langone Medical Center.
This is certainly so in light of Joseph's study.
Divorces had the highest rate of cardiovascular health problems, followed by widows, with a rate only slightly higher than married people.
Joseph's study was published in the journal Psychosomatic Medicine.