Cigarette smoking may speed progression of amyotrophic lateral sclerosis (ALS) and reduce survival in patients with the disease, according to a new collaborative study from Italian universities and research institutes.
The study, “Influence of cigarette smoking on ALS outcome: a population-based study” was published in The Journal of Neurology Neurosurgery and Psychiatry.
To assess the prognostic influence of premorbid smoking habits and vascular risk profile in the development of ALS, Adriano Chio, MD, medical and scientific director of the Department of Neuroscience at the University of Turin in Italy, and colleagues conducted a population-based cohort study involving 650 Italian patients with ALS. The researchers collected data on ALS patients’ smoking habits and also looked at chronic obstructive pulmonary disease (COPD) among these patients.
At time of diagnosis, about 19 percent of the ALS patients were regular smokers, 28% were former smokers and about 53% had never smoked.
COPD was diagnosed in 44 ALS patients, and half of those were former smokers. Patients with COPD had shorter lives than those without the disease. The researchers also identified that cigarette smoking seemed to shorten patients’ lives whether or not they had COPD when their ALS was diagnosed.
Current smokers with ALS had a significantly shorter median survival (1.9 years) compared with former smokers (2.3 years) and those who never smoked (2.7 years). Furthermore, current smokers were younger than others when their ALS was diagnosed.
“This study indicates that environmental factors and personal habits represent risk factors for ALS onset and can also influence its phenotype and prognosis. The discovering of the mechanisms, either genetic or epigenetic, through which exogenous factors influence disease phenotype is of major importance toward a more focused approach to cure of ALS,” the researchers concluded.
ALS is a fatal degenerative disorder of upper and lower motor neurons that affects muscle functions, including breathing, speaking and swallowing. In about 50% of cases, ALS also is associated with cognitive impairment ranging from frontotemporal dementia to milder forms of executive or dysexecutive impairment. In most cases ALS appears sporadically in the population; only about 10% of patients have a positive family history for ALS or frontotemporal dementia.
There is no cure for ALS, but evidence has shown that age, gender, genetics and underlying health issues are risk factors for this debilitating disease.