There are sulky silences, slammed doors and deafening rows. But for a woman in a strained marriage these are the least of her troubles. Scientists have found that marital misery takes a real toll on a wife's health.

She is more likely to show warning signs of heart disease, stroke and diabetes.Husbands in the same circumstances, however, seem unaffected. American psychologists studied 276 couples aged 40 to 70 who had been married about 20 years. Each filled out questionnaires on the good and bad aspects of married life.

Among the positives were mutual support and emotional warmth, while the negatives included arguments, hostility and disagreements over everything from children to money. The men and women were also given 'depression scores' based on self-reported symptoms.

They were then tested for 'metabolic syndrome' - a collection of symptoms known to increase the risk of heart disease, stroke and diabetes. In women, marital strain was associated both with depression and a larger number of metabolic syndrome symptoms.

Although husbands in unhappy marriages were also depressed, they avoided the adverse health effects suffered by their wives. The findings were presented yesterday at the American Psychosomatic Society's meeting in Chicago.

Metabolic syndrome is characterised by five symptoms: high blood pressure, a bulging waistline, high blood sugar, high triglyceride levels, and low levels of 'good' cholesterol. 'It's a little premature to say women would lower their risk of heart disease if they improved the tone and quality of their marriages - or dumped their husbands,' said Professor Tim Smith, who helped lead the University of Utah researchers.  'The immediate implication is that we should be concerned about not just traditional risk factors such as blood pressure and cholesterol but the quality of our emotional and family lives.'