(RxWiki News) Smoking cigarettes may be linked to increased risk of developing amyotrophic lateral sclerosis (ALS), otherwise known as Lou Gherig's disease.
A new study from Harvard School of Public Health finds that of the 832 patients who developed ALS from a pool of 1.1 million study participants, those who had ever smoked cigarettes at the beginning of the study had an increased risk of ALS compared with those who had never smoked. Current smokers and former smokers showed increased risk of developing the fatal neurodegenerative disease by 42 percent and 44 percent, respectively.
The risk for developing ALS also increased for the number of pack-years smoked (meaning the number of packs per day and the number of years that quantity was smoked). This increase jumped 10 percent for each increment of ten cigarettes smoked per day and 9 percent for each decade spent smoking.
Researchers say several possible mechanisms may be at play, which may help explain the smoking-ALS correlation. Direct neuronal damage from nitric oxide from cigarette smoke as well as cigarette smoke's generation of free radicals might play a role. Furthermore formaldehyde was shown to increase ALS risk in a 2008 study. (Formaldehyde is a by-product of tobacco smoking.)
ALS affects 5,500 new patients each year in the United States, most of whom are over 50. The disease is characterized by muscle weakness and atrophy leading to paralysis and finally death, usually within six years from diagnosis.