Married, ladies? Best check your blood pressure. Women in strained relationships are more likely to be overweight, have high blood pressure and suffer from the signs of "metabolic syndrome" – a range of risk factors that can lead to heart disease, stroke and diabetes.
Whereas women are likely to suffer ill health as a result of living in a bad marriage, the same does not appear to be the case with men, who were unaffected physically by stressful wedlock.
Scientists believe the underlying reason for the gender differences lies in the fact that depression in women brought on by marital rows and arguments is more likely to lead to metabolic disorders than depression in married men. "We hypothesised that negative aspects of marriages like arguing and being angry would be associated with higher levels of metabolic syndrome. We further anticipated that this relationship would be at least partly due to depressive symptoms," said Nancy Henry of the University of Utah in Salt Lake City.
"In other words, those who reported experiencing more conflict, hostility and disagreement with their spouses would be more depressed, which in turn would be associated with a higher risk of heart disease due to metabolic syndrome. We found this was true for wives, but not husbands."
Ms Henry added: "We know from previous research that women are more sensitive and responsive to relationship problems than men. The results of this study suggest those problems could harm their health.
"The gender difference is important because heart disease is the number one killer of women as well as men, and we are still learning a lot about how relationship factors and emotional distress are related to heart disease."
The scientists interviewed nearly 300 couples aged between 40 and 70 who had been married for an average of 20 years to assess each relationship's positive and negative aspects. Every man and woman also underwent a medical check-up to monitor such things as waistline and cholesterol levels.
Tim Smith, professor of psychology at Utah, said that personal relationships may play a significant role in increasing the known risk factors that can affect heart disease and stroke – but it is too early to say now whether some women would be better off leaving their husbands, not least because divorce also increases the risk of heart problems.
"The immediate implication is that if you are interested in your cardiovascular risk – and we all should be because it is the leading killer for both genders – we would be concerned about not just traditional risk factors, but the quality of our emotional and family life," Professor Smith said.