Kicking the habit improves smokers’ arteries

Many who quit gain weight, but study shows they still see health benefit

A year after kicking the habit, smokers' arteries showed signs of reversing a problem that can set the stage for heart disease, according to the first big study to test this.

The improvement came even though smokers gained an average of 9 pounds after they quit, researchers found. Their levels of so-called good cholesterol improved, too. 

"A lot of people are afraid to quit smoking because they're afraid to gain weight," said the study's leader, Dr. James Stein, a University of Wisconsin-Madison cardiologist.

The new research shows these people gain a health benefit even though they pick up pounds that hopefully can be shed once they've gotten used to not smoking, he said.

Smoking is one of the top causes of heart disease, and about one third of smoking-related deaths in the U.S. are due to heart disease. A heart attack often motivates longtime smokers to give it up.

Quitting is known to lower the risk of developing or dying of lung cancer. This is the first major clinical trial to show it quickly improves artery health. Results were published in the Journal of the American College of Cardiology and presented at the group's annual conference on Monday.

In the study, 1,500 smokers were given one of five methods to help them quit — nicotine patches; nicotine lozenges; the drug bupropion, sold as Wellbutrin and Zyban; or a combination of patches and lozenges or the drug and lozenges. A sixth group received a dummy treatment.

After one year, 36 percent had quit, and it made no difference which method they used, Stein said.

Before the study started and one year after smokers quit, doctors did ultrasound tests to see how well blood vessel linings relaxed and handled blood flow. Hardening of the arteries is an early step to heart disease. Using a tourniquet, they stopped blood flow in the forearm for a few minutes, then measured how a major artery responded when the flow was restored.

"It's a valid test" and is considered a good sign of how healthy the heart arteries are, said Dr. Alfred Bove, a Temple University heart specialist and president of the cardiology group.

Doctors found that artery function improved 1 percent in the quitters.

"That may not sound like much," but research shows that translates to a 14 percent lower risk of developing heart disease, Stein said.

"It's a small improvement at one year. The question is, do these folks keep getting better?" Bove said.

The study is continuing another two years to give an answer, Stein said.

London-based GlaxoSmithKline PLC provided smoking cessation medicines for that part of the study, and several authors have research funding from the company. Federal government grants paid for the artery study.

 

If you smoke too much 'blame your genes', say experts

A nicotine addiction drives some people to smoke more than others

Smokers who find it hard to cut down or quit may be able to blame their genes, new research suggests.

Scientists identified three genetic mutations that increase the number of cigarettes people smoke a day.

And several genes appear to dictate how likely you are to take up smoking and how easily you can quit.

Three separate studies collected data from 140,000 people, with the results published in the journal Nature Genetics.

A previous study two years ago found a common single-letter change in the genetic code linked to nicotine addiction and lung cancer risk.

This new research confirms this discovery and also pinpoints two more genetic variants that seem to increase cigarette consumption among smokers.

Lung cancer risk

The new single-letter mutations, known as single nucleotide polymorphisms or SNPs, lie in regions of the DNA molecule containing genes believed to influence nicotine addiction.

In smokers, each copy of the variants was associated with a small increase in smoking consumption equivalent to about half a cigarette a day.

However they also conferred a 10% increase in lung cancer risk, raising questions about their effect.

It is not clear whether the variants simply drive people to smoke more, or increase susceptibility to cancer as well.

The University of North Carolina, Oxford University and Icelandic company deCODE were all involved in the research.

Dr Kari Stefansson, researcher and executive chairman of deCODE, stressed that smoking is bad for anyone's health.

"But it is even worse for some, and our discoveries continue to strengthen our ability to identify who those people are and give them a compelling reason to quit."

Amanda Sandford, research manager at ASH, a public health charity, cautioned that any potential benefits from this research were still a long way in the future.

"Smokers who want to quit should not wait for treatment tailored to their genetic make-up.

"There is an abundance of advice and treatments available already to help people stop smoking," she said.

Giving up smoking 'raises diabetes risk'

Giving up smoking sharply increases the risk of developing type-two diabetes, a US study suggests.

Researchers found quitters had a 70% increased risk of developing type-two diabetes in the first six years without cigarettes compared with non-smokers.

This is because they tend to put on weight.

However, the Annals of Internal Medicine study stressed that this should not be used as an excuse to carry on smoking.

The Johns Hopkins team also stress that smoking is a well known risk factor for type-two diabetes - as well as many other health problems, such as heart disease, stroke and cancer.

Researcher Dr Jessica Yeh said: "If you smoke, give it up. That's the right thing to do.

"But people have to also watch their weight."

The study, based on 10,892 middle aged adults who were followed for up to 17 years, found the risk of developing type-two diabetes was highest in the first three years after giving up smoking.

Around 1.8% of people giving up smoking developed type 2 diabetes each year during that period.

If quitters avoided developing the condition for 10 years, then their long-term risk returned to normal.

People who made no effort to give up smoking had a constant 30% increased risk of type-two diabetes compared with non-smokers.

Blood sugar

Type-two diabetes means the body either fails to make enough of the hormone insulin, or cannot make proper use of it, leading to uncontrolled blood sugar levels.

Untreated this can cause serious disease, and complications such as blindness, kidney failure and nerve damage.

One of the major risk factors for the condition is being overweight, and the rise in obesity across the developed world has been blamed for a big increase in type-two diabetes.

The researchers found those who smoked the most and those who gained the most weight had the highest likelihood for developing diabetes after they quit.

On average, during the first three years of the study, quitters gained about 8.4lb (3.8kg).

The researchers said doctors should keep in mind the importance of weight control when counselling people about giving up smoking.

Quitters tend to put on weight because smoking acts to suppress appetite.

The use of nicotine replacement therapy has been shown to blunt the weight gain associated with giving up smoking.

Martin Dockrell, of the anti-smoking charity Ash, said: "The researchers are clear that smokers should quit but - especially if you are a heavy smoker or are already overweight - you might want to gently increase your exercise when you quit.

"If you are a smoker who is also overweight you should talk to your doctor about how to get the best from quitting.

"A little more exercise could help improve your sense of well being, reduce weight gain and undo some of the harm done by smoking leading to a healthier, happier you."

Natasha Marsland, of the charity Diabetes UK, said: "On no account should people use the theoretical results of this study as an excuse not to give up smoking.

"The health benefits of giving up smoking far outweigh the risk of developing type-two diabetes from modest, short-term weight gain."