THURSDAY, DAY 4
THE MIND
New York Yankee Lou Gehrig (1903–1941) is remembered for his major league baseball records and his consecutive game streak in the 1920s and ’30s—and for his tearful retirement at age 36, when he was diagnosed with the fatal disease that now bears his name. Amyotrophic lateral sclerosis (ALS), often referred to as Lou Gehrig’s disease, causes motor neurons in the brain and spinal cord to degenerate, leading to muscle weakness, coordination problems, and, eventually, total paralysis and death. Throughout the progress of the disease, mental function is not affected.
ALS attacks voluntary motor muscles, including those used for walking, talking, gesturing, and breathing. (Breathing is both involuntary and voluntary, because you can stop breathing—at least temporarily—on cue.) As neurons die, these muscles waste away: Limbs begin to look thinner, and people with ALS may experience weakness, twitching, cramping, slurred speech, and difficulty using their arms and legs. They may trip, drop things, or go through periods of uncontrolled laughter or crying. In more advanced stages, they may need a permanent ventilator in order to breathe.
About 15 new cases of ALS are diagnosed in the United States every day; 60 percent of these individuals are male, and 93 percent are Caucasian. Most people develop symptoms between the ages of 40 and 70 and live for 3 to 5 years after diagnosis—although for some, the disease advances less quickly or, in rare cases, may halt completely. The medication riluzole (Rilutek) can minimize the release of the chemical glutamate, an effect that appears to help slow the illness’s progression in some cases. Scientists aren’t sure why, but people with ALS have more glutamate in their spinal fluid than healthy people do.
Most cases of ALS are sporadic, meaning they affect people with no family history of the disease. The illness is hard to diagnose; doctors must perform blood tests, x-rays, and electrical nerve stimulation tests, and rule out all other diseases. About 5 to 10 percent of cases appear to run in the person’s family, and in 1991, scientists linked this type of ALS to a gene on chromosome 21. Today, a genetic test can determine familial ALS, although diagnosis is still based mainly on symptoms.