ATLANTA, Georgia (CNN) -- During the first seven years of their relationship, Judy Kelly doesn't remember her boyfriend, Bill Horrisberger, ever going to a doctor.
Bill Horrisberger, right, put off going to the doctor for more than a month, despite chest pains and shortness of breath.
"On a scale of one to 10, Bill was a zero," Kelly remarked when asked about her partner's willingness to get an annual checkup.
It turns out Horrisberger, 62, a retired English teacher from Atlanta, Georgia, isn't the only man who is reluctant to put on a hospital gown.
The Agency for Healthcare Research and Quality estimates that American men are 25 percent less likely than women to visit a doctor.
"A lot of times, it's very difficult for them to be convinced that they need to see a physician for a problem," said Dr. Allen Dollar, a cardiologist with Emory School of Medicine in Atlanta. "To a large extent, there is a lot of denial going on, and in some cases, that denial can be deadly." Watch the battle to get men to the doctor »
Denial is an understatement for Horrisberger, one of Dollar's patients.
Horrisberger was short of breath and experiencing chest pains in early December. Despite Kelly's repeated requests, he put off a doctor's visit for more than a month.
"There might have been some fear. My father had heart disease," admitted Horrisberger, who ended up having an operation to replace a faulty aortic valve and triple bypass surgery.
"There are a lot of things in Bill's story that could have been done preventionwise," Dollar said. The heart problems "didn't show up overnight."
Horrisberger admitted he's learned his lesson about getting regular checkups. "You don't know everything about yourself, so it would be a good idea to have someone else look at you," he said.
That closer look by a doctor shouldn't be just every now and then when a patient feels bad.
Dr. David Dodson, an expert on men's health at the Marino Center in Wellesley, Massachusetts, recommends that healthy men under 50 get a regular checkup every 18 months. After 50, he suggests, men should see their doctors annually.
"Men should take their health seriously," said Dodson, who is also the chairman of the Men's Health Committee for the Massachusetts Medical Society. "It's not just for their own sake. It's because men are part of families, and families depend on them."
Health problems don't just affect older men, he said. Certain cancers, such as those of the testes and skin, are more common in young men.
Younger men are also at higher risk than older men for sexually transmitted diseases, Dodson noted. And some men should talk to their doctor about being tested for gonorrhea, syphilis, chlamydia and HIV, the health care research agency suggests.
As men age, Dodson said, they are more likely to develop high cholesterol and high blood pressure. Those conditions can increase the risk of heart disease, stroke and diabetes.
"The older you get, the more important those exams are," Dodson said.
Around age 50, he wants men to be screened for colon and prostate cancer, in addition to regular blood pressure, cholesterol and blood sugar tests.
"There are so many things that go on in the human body that have no warning signs whatsoever until disaster strikes," he said.
At least half his male patients end up making an appointment only after they've been prodded by a wife or other loved one, the doctor added.
Looking back, Horrisberger wished he had listened to his girlfriend earlier and not waited to see the doctor.
"Once he got started and realized what was at stake, he was a good patient," Kelly said with a smile.