Amyotrophic lateral sclerosis (ALS), commonly known as Lou Gehrig's Disease, destroys the function of motor neurons, nerves that connect the brain and spinal cord with skeletal muscle (muscles that are under voluntary control); it does not affect cerebral function or peripheral sensation. Most cases begin with weakness in an extremity while about 30% begin with "bulbar symptoms," such as slurred speech or difficulty swallowing; in either case, the muscular dysfunction gradually spreads and eventually impairs the patient's ability to eat and breathe without artificial assistance. The majority of ALS patients succumb to the disease within three years while some cases progress more slowly and a small minority of patients experience a temporary or permanent halt in its progression; ALS may develop from early adulthood through advanced age and, in younger age groups, is more common in males.
According to the ALS Association, the disease affects 2 in 100,000 Americans; about 5600 new cases are diagnosed each year and, at any given time, approximately 30,000 Americans have the disease. Ninety percent of ALS cases are sporadic while 10% are inherited; several genetic abnormalities have been associated with the disease though their specific effects remain poorly understood. Other clues to the pathophysiology of ALS are an increased concentration of glutamate in the brain and abnormal accumulation of specific proteins in the motor neurons, apparently reflecting defective transport within the neuronal axons. The incidence of ALS is significantly higher in athletes and military Veterans, raising the suspicion that brain trauma or other environmental factors may play a role in the disease; indeed, the incidence of ALS in Italian soccer players was found to be 11 times that of the general population.
Many researchers suspect that ALS is caused by a combination of genetic and environmental factors. Genetic research, linking specific gene abnormalities to motor neuron dysfunction, likely offers our best hope for treatments that will prevent, ameliorate or cure this devastating disease. Donations to support that research may be directed to the ALS Association.
