'Exciting times' for migraine business

By Richard Warry
Health editor, BBC News website

Migraine attacks can be extremely debilitating

Have you been troubled by a persistent painful headache for weeks but are worried about bothering the doctor, because you think it is just down to stress?

Maybe you should take a trip to the surgery, because the major cause of persistent headache is migraine.

However, many patients struggle through without ever seeking help.

And those that do may find they get short shrift.

Migraine is estimated to affect about 15% of the population, and is three times more common in women than men.

MIGRAINE Estimated to affect 15% of the population Three times more common in women than men Appears to be linked in some cases to hormonal changes associated with the menstrual cycle Strongly linked to family history Triggers include: change of weather, too much/too little sleep, stress, missing meals and alcohol Migraine headaches can last for up to 72 hours, they tend to produce a throbbing sensation on one side of the head They can interfere with movement, cause nausea and vomiting and hyper-sensitivity to light and sound

But experts believe that doctors miss the condition in as many as 40% of women and 50% of men who seek professional help.

Professor Peter Goadsby, a migraine expert from London's Institute of Neurology, said lack of awareness from patients and doctors is partly to blame.

"If you break your leg, people give you a lot of sympathy, you get a cast, and people sign it," he said.

"But if you have migraine, you do not get a medal, or a cast - you look normal."

But although it is not always easy to diagnose, migraine can be extremely debilitating. The World Health Organization rated the effect a severe migraine attack on a par with being psychotic or quadriplegic.

The cost to the UK economy is estimated to be as much as £5bn a year.

Brain chemistry

Drugs are available to treat migraine attacks, and to reduce the risk of recurrence, but Professor Goadsby said they were not used enough.

It is estimated that just 8% of patients in the UK receive triptans which alter brain chemistry to ease the symptoms of an attack.

And figures from the US suggest just 15% of patients are using preventative medications - when nearly three times that number could potentially benefit.

Part of the problem is that most anti-migraine drugs carry a risk of side effects, such as drowsiness, weight gain and rashes.

About one in five patients who take Topiramate, one of the newest of the preventative drugs, experiences cognitive problems.

And of even more concern is that fact that drugs such as triptans constrict the blood vessels - raising the risk of heart attack and stroke in vulnerable patients.

This means that patients must weigh up the benefits against the risks - although most decide they are willing to take a chance to relieve the misery of their condition, even though some drugs only work in about half of cases.

Nerve cells

However, Professor Goadsby said new drugs were currently in development which promised to take migraine medication to the next level.

On the preventative side, early clinical trials are under way of a drug called tonabersat, the first of a new class called gap junction blockers, which work in a completely new way, influencing the chemistry at crucial points where nerve cells talk to each other.

Nobody knows quite how the drugs work, but it is thought they may be able to dampen down the nerve cell over-activity associated with migraine.

Professor Goadsby said it was too early to draw any firm conclusions about tonabersat, but he is hopeful that because it has a completely new method of action, it could represent a great advance.

New drugs are also being developed to ease migraine symptoms - and crucially they do not constrict the blood vessels.

These drugs work by blocking a chemical - calcitonin gene-related peptide (CGRP) - which is found at higher levels in the brains of people with migraine.

Results of the trials of the latest of these drugs, due be to unveiled at a meeting of the American Headache Society later this month, show that not only are they safer than currently available alternatives, they double the chances that a patient will stay headache-free for at least 24 hours.

"It is quite exciting being in the migraine business at the moment," said Professor Goadsby.

"A lot of new things are coming along based on entirely new mechanisms that have a sporting chance of making people's lives better."