'Smoking increases risk of MS'

Smoking can more than double a person's chances of developing multiple sclerosis, scientists revealed today.

A study found that smokers generally were nearly twice as likely to suffer the disease as people who had never taken up the habit.

Researcher Dr Trond Riise's study of 22,312 Norwegians found that smokers were 1.81 times more likely to develop MS than non-smokers.

For men, the risk of MS was 2.75 times higher, and for women 1.61 times higher, if they had ever smoked. The findings were reported in scientific journal Neurology.

A combination of genetic and environmental factors is thought to cause MS, which affects about 85,000 British people. Dr Riise said that tobacco chemicals might damage the immune and nervous systems, which would explain the increased risk among smokers.

And American scientist Dr Gary Franklin said factors such as smoking and diet might cause the disease to develop in people who are genetically susceptible to it.