Married men with prostate cancer have a much better chance of survival than bachelors - and "nagging wives" could be the reason, according to one New Zealand expert.
New research reported in the Canadian Journal of Urology showed that single men with the disease were 40 per cent more likely to die than husbands.
The study of more than 115,000 prostate cancer cases between 1988 and 2003 found that single men, including those who were divorced, widowed and separated, were more at risk even when factors such as age and tumour grade were eliminated.
Otago University lecturer Dr Elspeth Gold said the findings were likely to reflect that married men were encouraged by their wives to go to the doctor.
"It could be a certain amount of the nagging wife syndrome. They encourage men to go and get checked out rather than put up with them moaning about not feeling well."
Prostate cancer is the most common cancer in New Zealand men, with about 2500 cases diagnosed every year.
Dr Gold said it may be detected earlier by those in a sexual relationship because erectile dysfunction could be an early indicator.
"If you're in a committed relationship, and it's a sexual relationship, anything wrong with anything down there, you want to get it fixed fairly quickly."
She said a separate Australian study had concluded that bachelors were less likely to seek help for reproductive health problems.
The 2006 study found men who had never married were less likely to visit a doctor, while divorced or separated men were less likely to have had a prostate test.
She said the key message for men was to talk to their doctor.
"Prostate cancer, if picked up early, is treatable. It's not a death sentence, and the only way it's going to be picked up early is to start the dialogue with your health professional."
Other studies have also shown that married people have better health outcomes than their single counterparts.
One US study last year showed married people were three times more likely to survive lung cancer than patients who are single, while a 2011 Norwegian study found men who were never married were 35 per cent more likely to die from cancer than married men. Women who had never married were 22 per cent more likely to die from cancer.
An Otago University study also showed that long relationships, not necessarily marriage, were good for mental health.