No need to cast stones

Medical Matters:It may not be politically correct to say this, but I feel sorry for smokers. With so many social changes being imposed on them, many must feel they have become social pariahs.

While the public ban on smoking was based on the harm that passive smoking does to others, some sanctions against smokers ignore the fact that the habit is an addiction to a drug - nicotine - that for some people can be as difficult to come off as heroin or cocaine.

The British Health Secretary, Patricia Hewitt, has said that patients who smoke should be denied surgery until they give up smoking. This is an old chestnut, which is being actively debated by the medical profession.

Recent articles in a number of medical journals have discussed the issue of whether patients who smoke should be treated in the same way as non-smokers.

A vascular surgeon in Britain says when he is referred a patient who smokes and who has blockages to the leg arteries, he asks the GP to re-refer the patient when he has been six months off tobacco.

"By treating, for preference, those patients who have kicked this dangerous habit, I believe I am contributing to the nation's health and ensuring best value in terms of healthcare resource allocation," he says.

On the other side of the coin, the director of professional activities at the British Medical Association asks: "If treatment is denied to smokers, what about other illness-causing activity . . . Should we refuse treatment to those who attend an emergency room on a number of occasions after alcohol-induced accidents? Do we tell the overweight person that we will not treat their hypertension and diabetes?"

A professor of bioethics points out that doctors routinely treat patients who are despised by the society in which they live, such as enemy troops, terrorists and murderers.

In the light of this, he wonders why doctors would question whether they should treat smokers.

Personally, I think we need to consider the issue from the point of view of addiction.

Defined as the physical or psychological dependence on either a substance or an activity, addicts feel fine as long as their addiction is being fed.

But if they are deprived of the substance, then they suffer physical effects such as sweating and tremor. Tension, anxiety and depression are among the psychological effects of withdrawal.

Writing in his book Flagging the Problem - a new approach to mental health, Dr Harry Barry says that all addictions behave in a similar biological manner in the brain.

Normal pleasurable activities involve the stimulation of the neurotransmitter, dopamine, and the activation of the "pleasure box" in the centre of the brain.

In someone who is genetically or environmentally at risk of addiction, a persistent hyperstimulation of the dopamine system causes chemical and molecular changes within the pleasure box. The mood box at the front of the brain also plays a role in consolidating the addiction.

But perhaps one of the most interesting discoveries is that the chemical changes which cause the malfunction in the pleasure box are the same for all addictions. This opens up the prospect of developing drugs capable of treating all forms of addiction.

Until recently, the mainstay of anti-smoking treatment has been nicotine replacement therapy (NRT), given as a patch, gum, inhaler or tablet. The antidepressant drug buproprion (Zyban) is also used and has been shown to approximately double the odds of quitting.

But based on a greater understanding of the neurobiology of nicotine addiction, a new drug, varenicline (Champix), has been specifically developed for smoking cessation.

When nicotine binds to specific receptors in the brain, it causes a release of dopamine in the pleasure box. This causes feelings of pleasure and calmness. But when a person stops smoking, the drop in dopamine leads to withdrawal symptoms of irritability and stress.

Champix does two things; it prevents nicotine from binding to the receptors, while at the same time causing a smaller, steadier release of dopamine that helps reduce and minimise withdrawal symptoms.

Like all drugs, Champix has side effects which include insomnia, abnormal dreams and headache. Some 30 per cent of those who took the drug complained of nausea, although the quit rates in the clinical trails were impressive.

However, the new drug is not a magic pill, its inventor says. "The magic is believing in yourself and not underestimating your power to succeed," says Jotham Coe, a chemist with the drug company, Pfizer.

And while willpower will always be the key to beating any addiction, the development of Champix is likely to lead to the synthesis of other drugs that will help people kick alcohol, gambling and other addictions.

In the meantime, we must be wary of moving towards a more "healthist" agenda and of drifting away from the principle of treating every patient as an individual with particular needs.

Dr Houston is pleased to hear from readers at mhouston@irish-times.ie but regrets he is unable to reply to individual medical queries.