ALS is one of a group of disorders known as motor neuron diseases and is characterized by the progressive degeneration and eventual death of nerve cells in brain, brainstem and spinal cord. ALS can affect the neurons in the brain or the neurons in the spinal cord which can affect the ability to initiate and control voluntary movement. ALS can ultimately lead to respiratory failure as individuals lose the ability to control muscles in the chest and diaphragm.
The exact cause of ALS is not known; however, several factors have been proposed such as infection with unidentified virus, abnormal immune response, toxic exposure to certain minerals, and/or other factors. Approximately 10% of all cases are suspected are familial. The median age at which symptoms develop is 55 years and it affects males (60%) more than females (40%). It is believed to affect 30,000 people in the US with 5000 new cases diagnosed each year.
Early symptoms include muscle weakness, clumsy hand movements, and/or difficulty with tasks requiring fine motor skills. Weakness of lower limb can cause tripping and falling. Affected individuals may have difficulty swallowing, and speech may be slowed. Other symptoms include progressive weakness of the lips ad impairment and/or loss of function of the tongue, mouth, and/or voice box. Leg cramps affecting the calf and/or thigh muscles at night is also often observed. Over time additional muscles get involved and has a different speed of progression in different individuals.
Other symptoms include uncontrolled twitching of muscles, stiffness in leg, and/or coughing. As the disease progresses, the ability to move decreases and is associated with a marked reduction in weight (~5%). As the ability to move becomes progressively impaired, there is an increased risk of respiratory failure. There are also risks associated with inhalation of food or stomach contents into the lungs leading to inflammation. A declining ability to swallow may result in inadequate nutrition.
Diagnosis is primarily made by ruling out other potential conditions. Treatment typically requires a team approach and includes physicians, physical therapists, speech pathologists, pulmonary therapists, medical social workers, and nurses. Information about current clinical trials can be found at www.clinicaltrials.gov and www.centerwatch.com. Supporting organizations include ALS Association, Cure SMA, Muscular Dystrophy Association, and Spastic Paraplegia Foundation