More evidence that marriage may benefit overall health comes from findings that in the first year after having blocked blood vessels leading to the heart cleared, married patients fared much better than their unmarried counterparts.
Even after researchers adjusted for other cardiovascular risk factors such as smoking, family history and high cholesterol, unmarried patients were more than twice as likely to die and to experience major cardiovascular events like heart attacks, in the year following the procedure, known as angioplasty.
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Heart patients need a lot of support, and their care does not end in the hospital, the study's senior author, Dr. Ron Waksman of the MedStar Washington Hospital Center in Washington, D.C., said. "The implication is if you do not have someone to take care of you, you should be flagged for special care."
Previous research has found an apparent health benefit from marriage, but it is poorly understood and the results are not always consistent. For instance, bad marriages have been linked to heightened stress hormones and inflammation, both of which raise risks for heart disease and other illnesses.
But enough evidence suggests a positive marriage effect that Waksman's team set out to try to measure it in patients getting angioplasty to clear blocked coronary arteries - either to stave off a heart attack or as a result of already having had one.
The researchers analyzed the records of 11,216 patients gathered over 18 years through telephone contact or office visits. The patients' average age was 64, and 55 percent were married while 45 percent were unmarried. The singles group included people who were never married, widowed or divorced; 65 percent of them were men, 66 percent were white and 26 percent were African American.
Although high cholesterol and family history of heart disease were both more common among married individuals, it was the singles who were more likely to have major heart problems - including death, a heart attack or need for another angioplasty - in the year following their procedure.
The trend started right after patients underwent angioplasty, with 1.1 percent of unmarried patients dying in the hospital, compared to 0.4 percent of married patients, according to the results published in American Heart Journal.
Within 30 days of their procedures, 3.1 percent of unmarried patients had major cardiovascular events, compared to 1.2 percent of marrieds. At one year, 13.3 percent of singles versus 8.2 percent of marrieds had major cardiovascular events, and singles were also more than twice as likely to die of any cause.
The apparent marriage benefit was more pronounced for men compared to women. And the researchers caution that the singles were generally sicker before their procedures, for example they were more likely to have had a heart attack that prompted the angioplasty.
Theories about the role of marriage in health mainly come down to the possibility that healthier people tend to get married, or that spouses take care of one another better than individuals living alone take care of themselves or that the social and emotional support of a spouse has positive physiological effects.
Waksman thinks the stress-buffering effects of marriage are important. He also noted that patient compliance, including adherence to a medication or exercise regimen is generally a major issue in cardiac care, and that a partner is more likely to assist with this.
"What drove us to do this study is we see that many patients do not adhere to their medications, and when we ask why we get all kinds of answers," he told Reuters Health.
"These findings should heighten awareness of physicians to socioeconomic risk factors beyond the standard cardiovascular disease risk factors and may encourage domestic partners to be more engaged in the health care process after cardiac interventions," Waksman said.
In another recent study, Harry Reis, professor of psychology and Kathleen King, professor emerita at the School of Nursing at University of Rochester, found that married patients were 2.5 times more likely to be alive 15 years after coronary artery bypass surgery compared to unmarried patients.
And the quality of the marriage did make a difference: those with high-satisfaction marriages were 3.2 times more likely to be alive 15 years after bypass surgery compared to those reporting low marital satisfaction.
Multiple factors probably account for the marriage benefit, Reis said, "most likely a combination of spousal support and survivor motivation to adopt a healthy lifestyle, along with the provision of emotional support." All this, in turn, could influence physical processes responsible for slowing the advance of cardiovascular disease, he added.
Mary Whooley, a professor of medicine at the VA Medical Center in San Francisco, and at the University of California, San Francisco, said patients with poor social support are less likely to exercise, to eat well and to seek medical attention.
Whooley, who studies the interactions between depression and heart health in particular, told Reuters Health unhealthy behaviors can lead to biological changes that can increase the risk and severity of heart disease.
"We know that most of this is about health behaviors," she said, noting there are measures that can help people improve their medical adherence when they do not have a spouse. The important intervention is to ensure that individuals feel "there is someone they are accountable to."
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