Scientists in the US have found a possible link between smoking and motor neurone disease.
Figures from five long-term studies showed smokers had a 42% higher risk of developing a form of the disease than those who had never smoked.
Ex-smokers had an even greater risk – 44% – of having amylotrophic lateral sclerosis (ALS) than people who had never smoked, the study by researchers from the Harvard School of Public Health in Boston found. The risk rose 9% for every 10 years of smoking.
Heavy smokers were at greater risk than lighter smokers, according to the scientists, who found the risk increased by 10% for every 10 cigarettes smoked each day.
Writing in the journal Archives of Neurology, the researchers said: 'Several possible mechanisms by which cigarette smoking might influence the risk of ALS have been suggested, including direct neuronal damage from nitric oxide or other components of cigarette smoke (such as residues of pesticides used in tobacco cultivation) or from oxidative stress.
'Better understanding of the relation between smoking and ALS may further the discovery of other risk factors and help elucidate the nature of the disease.'
ALS causes degeneration of nerves and leads to wasting, weakness and decreased control over muscles. There is no cure.
"One of the best things about this research is that it puts the responsibility for the occurrence of als right where it belongs, with people. Rather than acting as if als or mnd develops randomly, without apparent logic, this research shows a connection between people's choices and their health situations, and this one little insight is just the beginning. Over time it will become increasing obvious that mnd or als is indeed a created problem underlied by chosen factors and patterns in peoples lives" - Marty Murray, US
"I have just been reading about formaldehyde and mnd or als my husband is in the end stages now on a ventilator after only 14 months of being diagnosed he was a smoker and this is in cigarettes is it not interesting wish someone could figure it out so we can work on a cure" - Tracey Gibb-Hudson, Leeds