Health Highlights: Oct. 7, 2008
Most Over 75 Shouldn't Have Colon Cancer Tests: Report Diet High in Meat, Dairy May Increase Prostate Cancer Risk Study Suggests Link Between Air Pollution, Appendicitis One-Quarter of Mammals Face Extinction: Report
Here are some of the latest health and medical news developments, compiled by editors of HealthDay:
Most Over 75 Shouldn't Have Colon Cancer Tests: Report
Routine colon cancer tests should not be given to most people over age 75, according to updated U.S. Preventive Services Task Force guidelines released Tuesday.
The government-appointed panel of independent medical experts reviewed available evidence and concluded that the benefits of detecting and treating colon cancer decline after age 75, while the risks increase. They noted that colonoscopy can cause complications such as infection, perforated colon and reactions to sedatives, the Associated Press reported.
A patient's medical history and risk factors may make colon cancer screening worthwhile for some people between the ages of 76 and 85. But, there's little reason for routine screening among patients older than 85, according to the guidelines, which were published in the journal Annals of Internal Medicine.
In a break with other medical and cancer organizations, the task force didn't give its stamp of approval to three new colon cancer screening tests -- a stool DNA test; the X-ray test called virtual colonoscopy; and CT colonography. The task force said these tests require more research, the AP reported.
The task force did endorse three tests and recommended all Americans ages 50 to 75 get screened with one of them: a colonoscopy of the entire colon every 10 years; a sigmoidoscopy of the lower colon every five years, combined with a stool blood test every three years; a stool blood test every year.
Diet High in Meat, Dairy May Increase Prostate Cancer Risk
Eating a lot of meat and dairy products may boost prostate cancer risk, say British researchers who analyzed the results of 12 studies than included a total of nearly 9,000 men.
A diet high in meat and dairy products increases levels of a hormone called Insulin-like Growth Factor-1 (IGF-1), which promotes cell growth. The University of Oxford team found that men with high levels of IGF-1 were up to 40 percent more likely to develop prostate cancer than men with low levels of the hormone, BBC News reported.
The amount of influence that diet has on IGF-1 levels is unclear, but levels of the hormone may be up to 15 percent higher in people who consume a lot of meat and diary products, said lead researcher Dr. Andrew Roddam.
"There is a need to identify risk factors for prostate cancer, especially those which can be targeted by therapy and/or lifestyle changes. Now we know this factor is associated with the disease and we can start to examine how diet and lifestyle factors can affect its levels and whether changes could reduce a man's risk," said Roddam, BBC News reported.
The study was published in the journal Annals of Internal Medicine.
Study Suggests Link Between Air Pollution, Appendicitis
There may be a link between air pollution and increased risk of appendicitis, suggests a Canadian study.
University of Calgary researchers looked at more than 45,000 patients hospitalized for appendicitis between 1999 and 2006 and found patients were about 15 percent more likely to be hospitalized on days with higher levels of ozone and other air pollutants, BBC News reported.
This association was strongest during the summer, when people were more likely to be outside.
"If the relationship between air pollution and appendicitis is confirmed, then improving air quality may prevent the occurrence of appendicitis in some individuals," said lead researcher Dr. Gilaad Kaplan, BBC News reported.
The study was presented at an American College of Gastroenterology conference.
One-Quarter of Mammals Face Extinction: Report
About 25 percent of the Earth's mammal species are at risk of extinction, says a report compiled over five years by 1,700 experts in 130 countries. That figure could be as high as 36 percent because data on some species is so scarce, the Washington Post reported.
"Mammals are definitely declining, and the driving factors are habitat destruction and over-harvesting," said lead author Jan Schipper, the global mammals assessment coordinator for the International Union for the Conservation of Nature.
The report covers all 5,487 wild mammal species identified since 1500 and is the most thorough tally of land and marine mammals since 1996. It found that land and marine mammals face different threats and that large mammals are more vulnerable than smaller ones, the Post reported.
Habitat loss and hunting are the major threats facing land mammals, while marine mammals are most threatened by accidental killing through fishing bycatch, ship strikes and pollution.
The study was published in the journal Science.