May 5, 2000 -- First comes love, then comes marriage, then comes ... Lou Gehrig's disease? This seems to be true for nine married couples in France. In each case, both husband and wife have been diagnosed -- after years of marriage -- with the rare nerve disorder amyotrophic lateral sclerosis (ALS, more commonly known in this country as Lou Gehrig's disease.) Researchers studying these couples -- and their children -- hope to learn more about what part environment and genes play in this devastating disease. They presented their findings here at the 52nd annual meeting of the American Academy of Neurology.
ALS results in a gradual and ongoing destruction of the nerves that control the body's muscles. Symptoms include muscle weakness and cramping, uncontrollable twitching of the hands and feet, and slurred speech. As the disease progresses, it attacks nerves that connect to the muscles that control breathing - usually leading to death within 5 years of being diagnosed. According to the ALS Association, about 5,000 new cases are diagnosed in the U.S. each year, and there are 30,000 Americans with ALS at any given time.
The cause of ALS is unknown but is believed to be a combination of genes and environment. For example, a toxin sometimes used as a folk medicine by Pacific islanders has been associated with symptoms of ALS. Exposure to the virus that causes polio has also been suspected as a cause.
The French researchers, led by Philippe Corcia, MD, studied nine couples in which husband and wife both developed ALS. The couples ranged in age from 40 to 80 and lived together for an average of 20 years before coming down with the disease. When one spouse developed ALS, there was a lag time of 1-30 years before their partner began showing symptoms, but the average delay was 8 years.
Although husband-wife cases of Parkinson's and Huntington's diseases have been seen, this is the first report of marital ALS, says senior author William Camu, MD, a neurologist at the University of Montpellier, France. He explains that the occurrence is unlikely to be a coincidence.
"The risk of ALS is one in one million, and there are 20 million [married] couples in France," he says. "However, we have found nine cases in nine years." The researchers believe this happens because of the environment the couples share, rather than because of genetic factors. Just to be safe, however, Camu and his co-investigators are now studying the children of these nine couples to determine if there is also a genetic factor they can pinpoint.
"It is always interesting to speculate what [results like these] might mean," says Robin L. Brey, MD, associate professor of neurology at the University of Texas Health Science Center in San Antonio.
According to Brey, who reviewed the study for WebMD, some diseases are partial to certain ethnic groups, "so you always wonder if there's a genetic aspect in terms of the husband and wife being [distantly] related," she says. The findings may also "suggest a possible infectious process, or environmental exposure when they were children," she says -- with the effects being postponed for many years.
"This study has important implications for patients and for care," says Brey. The finding of an environmental toxin would be "a major breakthrough, because it [could ultimately] allow us to prevent the [nerve] damage that causes ALS."
- French researchers report they have found nine married couples where both husband and wife have a rare nerve disorder called amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease).
- ALS causes the nerves serving the muscles to continue to break down. At first, it causes twitching and slurred speech Within five years, patients usually develop fatal breathing problems when the disease involves those nerves.
- In the new report, the couples were married an average of 20 years before one spouse was struck with ALS. The other partner got the disease an average of eight years later, but doctors don't know why. Other nerve diseases have been shown to affect both spouses, but this is the first time it has been seen with ALS.