About two in 100 patients getting warfarin will have a serious hemorrhage, according to experts.

The blunt effect of warfarin is perhaps not surprising given that it was used as rat poison when it was discovered by University of Wisconsin researchers for its anti-clotting effect.

Excessive bleeding from the drug is one of the most common prescription-related causes of emergency room visits, according to the U.S. Institute of Medicine and other studies. ER visits are a major cost burden for hospitals.

Genetic testing for warfarin users could avoid 85,000 serious bleeding events and 17,000 strokes, saving up to $1.1 billion annually in health-care costs, a joint study by the Brookings Institute and American Enterprise Institute said last month.

Warfarin works by suppressing Vitamin K, which plays a key role in a coagulation cascade that leads to blood clotting. But it can go overboard and suppress too much Vitamin K, causing the excess bleeding.

"It is a public health issue. There is a small but steady problem that worries many clinicians about giving warfarin," Dr. Jay Preston Mohr, director of the stroke center at Columbia University Health Sciences, said.

Although drug companies are working on alternatives, the choices are few for certain patients, such as those with atrial fibrillation, a dangerous heart rhythm disturbance that boosts stroke risk, he said.

"It is not clear in the foreseeable future that there will be a challenge to warfarin as an oral anticoagulant," Mohr said.

Several sites are working on the problem, including the Mayo Clinic hospital system in Rochester, Minnesota. It said this week that its for-profit arm will begin testing whether its genetic test can predict patients' responses to warfarin and it will record the potential cost savings.

Mayo will use data from about 1,000 clients of Medco Health Solutions Inc., the biggest pharmacy benefits company, which runs drug plans for health insurers and employers with about 55 million patients.

Copyright © 2006 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.

Early drinking boosts risk of later alcohol abuse

Last Updated: 2006-12-06 14:18:54 -0400 (Reuters Health)

By Anne Harding

NEW YORK (Reuters Health) - Young men who start drinking earlier are significantly more likely to abuse alcohol later on in life, a new study of more than 40,000 Marine recruits confirms.

"Early alcohol use does seem to be a national problem," Dr. Margaret A. K. Ryan of the Naval Health Research Center in San Diego, one of the study's authors, told Reuters Health. And preventing this early use, she added, could make a "huge difference" in preventing alcohol abuse down the road.

Ryan and her team surveyed 41,482 men who began military training between 2002 and 2006, all of whom were 18 to 20 years old. The survey was done to gather initial data on these young men as they entered the military, in part, to better understand who decides to join the service and why, Ryan said.

Nearly 15 percent met the definition of risky drinking, 45.1 percent drank but were not risky drinkers, and 40.2 percent did not drink at all. The younger a man was when he started to drink, the more likely he was to abuse alcohol.

For example, boys who started drinking at age 13 were 5.5-times more lately to become a high-risk drinker. Men who smoked cigarettes were also about five times more likely to abuse alcohol. Other factors linked to problem drinking included coming from a rural area or a small town, household alcohol abuse or mental illness, and childhood sexual or emotional abuse.

The researchers also found that higher education and having many close friends and relatives made risky drinking more likely.

It's possible that the men who attended some college may have had greater exposure to binge drinking and heavy alcohol use, which is known to be more common among college students than 18- to 22-year-olds not attending college, Ryan and her team note.

The "unexpected" link between greater social support and risky drinking may have been because these young men were more likely to drink heavily "for reasons of conviviality and peer group pressure," the researchers add.

Ryan and her team found that men who reported joining the military because they sought travel or adventure or to escape problems at home were also more likely to abuse alcohol. Those who joined to serve their country were slightly less likely to be problem drinkers.

"That's not a comment on what's a good or bad reason to join the military," noted Ryan. "All of this is a comment on young people right at the point of joining the military. It says nothing about how they do in the service, about their drinking behavior in the service."

She added that she and her colleagues hope the military may prove a healthy environment for people who do join to leave problems at home, and their further research will help to answer this question.

SOURCE: Archives of Pediatrics and Adolescent Medicine, December 2006.

Copyright © 2006 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.