Tailored therapy seen for smokers

Jeff LaBahn, a 39-year-old technical support engineer from Raleigh, has tried to quit smoking five times, using nicotine patches and the prescription medication Chantix.

Each of his failures has added to a 20-year history of addiction.

"Nothing worked for more than three months," he said.

Now, for people such as LaBahn, a new treatment for tobacco addiction may be on the horizon - and it could be designed just for them.

Doctors may soon be able to customize therapies for individual smokers by tracking two personal tidbits: genetic makeup and dependence on nicotine.

A made-to-order treatment can increase the chances a smoker will quit for good the first time around, researchers say.

That's the chief conclusion of a joint study by scientists at Duke University and the National Institute on Drug Abuse, published this month in the academic journal Molecular Medicine.

The scientists found they could forecast a smoker's success at quitting by looking for telltale genes and how hooked the person was on nicotine.

"This is the first step to tailor treatment, based on information that can be collected before someone quits smoking, to help maximize the chances of succeeding," said Dr. Jed Rose, lead author and director the Duke Center for Nicotine and Smoking Cessation Research.

The findings point to a near future of personalized medicine, the movement to abandon a one-size-fits-all approach to treating patients in favor of a custom-fit therapy based on genetics.

The horrible toll

Smoking causes 443,000 deaths in the United States each year, the Centers for Disease Control and Prevention reports. It also inflicts an economic burden of $96 billion in direct medical costs and $97 billion in lost productivity.

But kicking the habit is not easy, and most smokers relapse within a few weeks or months.

Of the smokers who try to quit cold turkey, a mere 5 percent never go back. In the 1980s, Rose co-invented the nicotine patch, which ups the odds of succeeding to about 25 percent. Recent studies have suggested that starting a smoker on the patch two weeks before quitting can increase success rates even more.

Even so, too many people fail. It's never been clear why some people can quit smoking and others can't.

Scientists in the Duke-NIDA study think they might have some answers, and part of it has to do with genes.

Quitters' markers

In the study, each of 479 smokers underwent a genetic scan looking for certain markers shared by successful quitters.

These markers, which currently number more than 12,000, were discovered by the previous work of Rose and co-author Dr. George Uhl, chief of molecular neurobiology research at NIDA. The more of those traits smokers have, the more likely they will be able to stub out cigarettes for good.

The second factor, nicotine dependence level, was determined by a questionnaire.

The smokers were randomly divided into two groups, with half getting a standard 21 milligram daily dosage of patch and the others receiving a double dosage of 42 milligrams a day.

When the success rates were tallied 10 weeks later, the researchers came across some interesting patterns.

Nicotine dosage effects

Smokers who were unlucky on two fronts - with few successful-quitter genes and high levels of dependence - did much better when using the 42 milligram patch.

However, those who had weak genes offset by low dependence levels actually did worse on the higher dosage. They fared better on the 21 milligram standard.

Meanwhile, the genetically lucky did about the same on either therapy.

The take-away message, researchers say, is that different nicotine doses are more effective for different types of smokers.

Best advice: Keep trying

Still, some argue that genetic scans - even if accurate forecasters - may not add much to the assortment of predictive tools doctors already use.

"As a general rule, I would say that whilst research on genetic differences in smoking ... cessation is interesting, it is not yet likely to be of benefit for tailoring treatment for individual smokers," said Dr. Lindsay Stead of the Cochrane Tobacco Addiction Group at Oxford University. "The message is to keep on trying to quit, using any evidence-based method."

With the costs of a genetic scan dropping rapidly, Rose estimates that the findings may make their way into doctors' offices within three to five years.

"The technology is there to look for baseline genetic information," he said. "We want to use this information to yield a personalized approach to quitting smoking."

For LaBahn, taking advantage of any genetic information that could help him quit sounds like a good option.

"I think I'd have a better chance," he said.