Progression of ALS Disease

ALS, also known as amyotrophic lateral sclerosis or Lou Gehrig disease, is a progressive, incurable disease of the nervous system. It is fatal on average within a few years, though some people live longer. ALS causes muscle weakness, trouble speaking and swallowing, trouble breathing and changes in emotions and thinking. The first symptoms of ALS may be different from one person to the next, and the rate of progression also varies among people. This makes it difficult for doctors to predict what the disease course will be like for a specific person.

Muscle Weakness

According to the ALS Association, muscle weakness is the first symptom in 60 percent of people. It may start out in the hands or feet and can affect both sides to a different extent. Symptoms include trouble buttoning clothes, dropping things and tripping. Muscles twitch, can become stiff and cramp, and ultimately waste away. Over months to years, in most cases, the weakness spreads until all of the limbs are paralyzed. This progression happens at a steady rate for each person, although the overall rate of progression may be different between one person and another.

Difficulty Speaking and Swallowing

Difficulty speaking and swallowing can occur at any point in the progression of ALS, but they tend to be most pronounced later on in the disease. There is a form called bulbar-onset ALS in which these symptoms appear at the beginning, which is associated with a shorter survival. Speech may be soft, thick-sounding or slurred. There may be drooling. When swallowing, liquid may come out of a person's nose, or solids may stick in a person's throat. There is a risk in this situation of aspiration -- food going into the lungs -- which could cause pneumonia.

Respiratory Symptoms

Trouble breathing -- causing such symptoms as shortness of breath, fatigue, disturbed sleep, or morning headaches -- can occur at any point in the progression of ALS. It worsens over time and is generally the cause of death. For some people, trouble breathing is the first symptom of ALS, and this is associated with shorter survival. According to an article in the December-October 2009 issue of "Amyotrophic Lateral Sclerosis," a person's respiratory muscle strength measured at the time of diagnosis is the single most important factor in predicting how quickly the disease will progress.

Other Factors That Affect Progression of ALS

According to the ALS Association, ALS is fatal on average within 2 to 5 years. But 10 percent to 20 percent of people with ALS live longer, according to an article in the December-October 2009 issue of "Amyotrophic Lateral Sclerosis." Age may be a factor -- those who are over 80 when they develop ALS tend to have a faster progression of the disease, while those under 40 may survive longer than average.

About half of all people with ALS have some problems with thinking, and 5 percent to 10 percent of them have a more severe problem called frontotemporal dementia. Both are associated with faster progression of the disease. Many other factors that affect the progression of ALS are being studied, including improved respiratory and nutritional care and psychological support.

When to Seek Medical Attention

You should seek immediate medical attention if you have difficulty breathing, trouble swallowing your saliva or your food, trouble speaking or muscle weakness.