There have been many warnings about smoking and smokers being liable to die young, but they mostly fall on deaf ears to many.

Researchers have found that smoking increases the risk of early death from motor neurone disease.

Smokers are also likely to see the symptoms of the disease, also known as amyotrophic lateral sclerosis or ALS, appear at a younger age, new research has suggested.

ALS is a progressive degenerative disease affecting nerve cells in the brain and spinal cord, and there is currently no cure for the disease.

In a bid to find out if tobacco might play a role in the development of the disease, a team of researchers gathered information on the smoking habits and evidence of respiratory disease (COPD) among 650 people diagnosed with ALS between 2007 and 2011 in one region of northern Italy.

Of the patients, 121 (18.6 per cent) were regular smokers at the time they were diagnosed with ALS.

Meanwhile, 182 (28 per cent) had stubbed out their habit before diagnosis, while 347 (53.4 per cent) were life-long non-smokers.

In total, 44 of the patients had COPD, which is known to shorten a person’s lifespan; 22 of them were ex-smokers.

The average survival of patients with COPD was shorter than that of people without it.

But smoking seemed to be linked to faster disease progression and how long a patient lived after diagnosis, whether or not they had underlying COPD.

Current smokers had a significantly shorter lifespan than did either ex-smokers or lifelong non-smokers.

This is an observational study, so no firm conclusions can be drawn about cause and effect, and while the researchers describe their findings as “intriguing,” they point out that as yet it is unclear how smoking might affect the development and progression of ALS.

The findings are published online in the Journal of Neurology Neurosurgery and Psychiatry.