THURSDAY, Sept. 22 (HealthDay News) -- Almost 7 percent of men 65 and older who have a prostate biopsy are hospitalized within 30 days of the procedure, a new study indicates.

By comparison, only about 3 percent of similarly aged men who do not get prostate biopsies can expect to be hospitalized, according to the report in the November issue of the Journal of Urology.

"The overall hospitalization rate is about twice as high as the average rate of hospitalization for the average person," said study senior author Dr. Edward Schaeffer, an associate professor of urology and oncology at the Johns Hopkins University School of Medicine in Baltimore

And, the increase in hospitalizations wasn't just for reasons that are clearly related to the biopsy itself. While the rate of infections increased significantly, there were also some hospitalizations related to flare-ups of heart failure and pneumonia, Schaeffer noted.

"That means that something about the biopsy is causing people to get sick and need admission to the hospital. We've always thought of prostate biopsy as a simple outpatient procedure, but it does stress the body," said Schaeffer.

Prostate cancer is one of the most common causes of cancer in American men, according to background information in the study. It is generally diagnosed through a trans-rectal biopsy. The doctor guides the needle through the rectum to take a sample from the prostate. This is done with the guidance of ultrasound imaging.

More than 1 million prostate biopsies are done each year in men who are on Medicare, according to the study.

The current research included a random sample of 5 percent of the men 65 and older who were on Medicare between 1991 and 2007. There were 17,472 men who had prostate biopsies and 134,977 men in the control group who did not have a prostate biopsy.

The mid-point age of the men was 73. Prostate cancer was diagnosed in just over 17 percent of the men who underwent a biopsy, according to the study.

The study found that 1,209 men -- 6.9 percent -- who underwent biopsy had to be hospitalized within 30 days of the biopsy. That compares to just 2.9 percent for the control group.

Infections were the primary reason for hospitalization in men who'd had a biopsy. In fact, men undergoing biopsy had almost 2.3 times the risk of an infection compared to men who did not have the procedure.

Schaeffer said the researchers believe the higher rates of infection likely correlate with a rise in antibiotic-resistant bacteria.

All men are put on antibiotics before undergoing a prostate biopsy to reduce the chance of infection, he said.

Hospitalizations for non-infectious complications were also higher in men who underwent biopsy, although they did not increase over time, according to the study. These hospitalizations were for reasons such as heart failure or pneumonia.

"What this tells us is that we really need to be aware if you are having this procedure that you have an underlying problem. And, we need to know when was the last flare-up," said Schaeffer.

Dr. Lee Richstone, director of laparoscopy and robotic surgery at The North Shore-LIJ Health System in New Hyde Park, N.Y., said: "This really is a major health concern. We have to really think very carefully about who to screen and who to biopsy for prostate cancer.

"Biopsies are not benign. You have to assess each patient's risk individually, and tailor screenings for each patient. Once you've made the decision, with the patient, to biopsy, you need to do what you can to prevent infectious complications," explained Richstone, who's also an associate professor of urology at Hofstra University School of Medicine.

It's important to know what types of bacteria are developing resistance in your particular geographic region, he said. And, he added, doctors should consider giving stronger antibiotics as a preventative. In his own practice, Richstone said they use two antibiotics before a biopsy to prevent infection.

Schaeffer said doctors can do a rectal swab prior to the biopsy procedure to check an individual patient to see if he carries antibiotic-resistant bacteria. In addition, he said, if you've had antibiotics recently for another reason, you may be more susceptible to infection, and should likely put off the procedure for a few months.

Some men may decide to forego the biopsy entirely. In some men with slow-growing prostate cancers, particularly if they are older, if they have other health conditions and if they are expected to die of another cause besides the cancer, experts often recommend "watchful waiting."

More information

Learn more about the tests that help your doctor evaluate the health of your prostate from the National Institute of Diabetes and Digestive ... Kidney Diseases.