Amyotrophic lateral sclerosis selectively affects motor neurons, both central and peripheral, and is characterized by muscle stiffness, muscle contractions and gradual weakness due to decreased muscle size. This results in difficulty speaking, swallowing, and ultimately breathing .
In 90% -95% of cases the cause is not known. About 5% -10% of cases are inherited from the parents and about half of these are due to one of two specific genes. Diagnosis is based on observing the patient's signs and symptoms and some diagnostic tests performed to rule out other possible causes.
There is no known cure for ALS. The study: Incidence of and Mortality From Amyotrophic Lateral Sclerosis in National Football League Athletes, published on the JAMA network open, explained: "Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease; understanding ALS risk factors is a critical public health issue.
To evaluate the incidence of and mortality from ALS in National Football League (NFL) athletes and to describe characteristics associated with ALS within this cohort. This population-based cohort study included all 19 423 NFL athletes who debuted between 1960 and 2019 and played 1 or more professional game.
It was conducted between October 3, 2020, and July 19, 2021. Cases of ALS and death information were identified based on public records from NFL statistics aggregators, news reports, obituaries, and National Death Index results.
The standardized incidence ratio and the standardized mortality ratio were calculated based on data acquired from surveillance studies of ALS accounting for age, sex, and race. Secondary analyzes examined the association of body mass index, NFL career duration, race, birth location, and markers of fame, using a nested case-control design, matching athletes with ALS to athletes without ALS, by NFL debut year.
Results: A total of 19 423 male former and current NFL players (age range, 23-78 years) were included in this cohort study and were followed up for a cumulative 493 168 years. Thirty-eight players received a diagnosis of ALS, and 28 died during the study time frame, representing a significantly higher incidence of ALS diagnosis and mortality among NFL players compared with the US male population, adjusting for age and race.
Among NFL athletes, nested-case-control analyzes found that those who received a diagnosis of ALS had significantly longer careers than athletes without ALS. There were no differences in ALS status based on proxies of NFL fame, body mass index, position played, birth location, or race.
The age and race-adjusted incidence of and mortality from ALS among all NFL players who debuted between 1960 and 2019 were nearly 4 times as high as those of the general population. Athletes with a diagnosis of ALS had longer NFL careers than those without ALS, suggesting an association between NFL duration of play and ALS.
The identification of these risk factors for ALS helps to inform the study of pathophysiological mechanisms responsible for this fatal neurodegenerative disease. "