Putting Out The Fire

Putting Out The Fire
Deccan Herald

Those who stop smoking experience positive health changes that are detectable within days, but it may take years for the medical risks in ex-smokers to drop to the levels enjoyed by those who have never smoked.


Smoking increases the risk of respiratory infections and chronic obstructive pulmonary disease. Smoking predisposes to oral, lung, and other cancers. Smokers are more likely to suffer from high blood pressure, and to experience a heart attack or stroke. Smokers are also at increased risk of disturbances ranging from dental caries to osteoporosis. Women smokers are more likely to have abortions. Their children are more likely to have behavioural disorders. Nonsmokers, who regularly inhale cigarette smoke also suffer higher medical risks.

A study of half a million Americans who were followed-up for an average of nine years showed that the risk of death was doubled in smokers. In contrast, those who stop smoking experience positive health changes that are detectable within days; but, it may take years for the heightened medical risks in ex-smokers to drop to the levels enjoyed by those who have never smoked. A message here is that one should not start smoking; but what can be done for those who already smoke and can’t stop?

Many medicines can help smokers drop their deadly habit. Smokers are addicted to the nicotine in cigarettes, but the chemicals in the tobacco tar are what especially harm health. So, nicotine replacement can help smokers quit cigarettes without suffering the symptoms of nicotine withdrawal. Nicotine replacement is available as a patch, gum, lozenge, inhaler, and spray. The patch is applied to the skin, the gum is chewed, the lozenges are sucked, the spray is sprayed into the mouth, and the inhaler is breathed in. Each method of delivery of nicotine has its advantages and disadvantages.

Bupropion is another effective treatment. Patients take this drug for about three weeks before attempting a clean break with smoking.

About half of treated patients successfully quit smoking within two months, but most gradually relapse during the rest of the year. It appears that, to remain tobacco-free, patients need to take bupropion for a year or longer; but stopping bupropion thereafter is again associated with relapse during the succeeding year. This tells us that smoking is a chronic disease for many; treatment merely keeps the disease at bay. A plus with bupropion is that it reduces the risk of weight gain and depression after successful withdrawal from tobacco.

Why does bupropion work? One reason is that it increases the availability of dopamine in the reward centres of the brain; dopamine is the reward chemical activated during smoking. Another reason is that the principal metabolite of bupropion blocks the receptors on which nicotine acts in the brain; this makes smoking less pleasurable.
Varenicline is the latest drug. It received approval in the USA in May 2006. It is the best treatment available to-date. Its efficacy was demonstrated in six trials in which 3,659 chronic smokers participated. Five of these studies were randomised controlled trials conducted on smokers who had previously averaged 21 cigarettes a day for about 25 years. In all five trials, varenicline outperformed placebo in smoking cessation rates. In two of the studies, varenicline was also superior to bupropion.

About 70 per cent of smokers can expect to remain tobacco-free if they take varenicline for six months; more than half of these smokers can expect to remain tobacco-free during the next six months even if they stop the treatment.

Varenicline produces nausea in about a third of patients but is otherwise well tolerated; few patients stop treatment because of side effects. Varenicline does not prevent weight gain associated with abstinence from smoking. Patients who successfully quit smoking during three months of treatment can extend treatment for a further three months to increase the chances of long-term abstinence. The drug weakly stimulates a part of the nicotine receptor in the brain. Thus, in a way it mimics nicotine replacement therapy. It also blocks the nicotine receptor, diminishing the effect of nicotine from cigarettes should smoking resume.

Clonidine and nortriptyline are older drugs with modest efficacy against smoking. Topiramate, which helps alcoholics kick their habit, may also reduce smoking in these patients. Rimonabant, an anti-obesity drug, modestly reduces smoking rates. A vaccine against nicotine is under development.

Merely providing a medicine is insufficient; smokers also need counselling on how to stay tobacco-free. This guidance is provided through cognitive behaviour therapy (CBT), a highly successful approach used to treat depression and other psychiatric disorders. Combinations of medicines may be more effective than one medicine alone.

It is unfortunate that, despite the terrible health price that smokers pay, few hospitals run special clinics for smokers. The National Institute of Mental Health and Neurosciences, Bangalore, is one centre with a tobacco cessation clinic.

By Chittaranjan Andrade

(The writer is a professor, NIMHANS, Bangalore)

Online at: http://www.deccanherald.com/Content/May312007/panorama200705314742.asp