By Bahar Gholipour, Staff Writer
Published: 08/23/2013 08:02 AM EDT on LiveScience
Men who show signs of early balding may be at an increased risk of the rare but incurable disease amyotrophic lateral sclerosis (ALS), also called Lou Gehrig's disease, a new study finds.
The link between the two conditions may provide a new direction in investigating the poorly understood neurodegenerative condition, the researchers said.
The researchers looked at more than 50,000 men ages 46 to 81, and asked them to recall the shape of their hairline at age 45, and choose from a series of pictures depicting no balding, moderate or extensive balding.
Nearly 44 percent of men reported no balding, about 42 percent of men reported moderate balding and 14 percent reported extensive balding at 45 years old.
Sixteen years later, 11 of 5,500 men who had reported extensive balding were diagnosed with ALS, while 13 of 17,500 men with no balding were affected by the disease. The researchers calculated that men with extensive early balding were about three times as likely to develop ALS, compared with men who hadn't lost hair early in life.
The researchers said their results should be interpreted cautiously until the link between early balding and ALS is confirmed in future studies.
"This doesn't mean that bald people should worry," said study author Elinor Fondell, researcher at Harvard School of Public Health. Moreover, the link may not be true for everyone -- there were 11 people diagnosed with ALS who didn't have early balding, Fondell noted.
ALS is a disease of the nerve cells in the brain and spinal cord that control muscle movement. The early symptoms of the condition usually include weakness and shrinking of muscles, and as the condition progresses, patients develop disabling movement problems, and ultimately cannot breathe on their own.
About 5,600 people in the United States are diagnosed with ALS each year, according to the ALS Association. Men are at higher risk for ALS than women. Half of people affected by the disease live more than three years after diagnosis, but less than 10 percent of patients live more than 10 years after diagnosis.
"We know very little about what causes ALS, and there's only one approved drug that prolongs life, for about three months," Fondell said.
"If the link between early balding and ALS can be confirmed in other populations, and if other researchers look at this on a molecular level and see if there's some basis to this, then that in the future may lead to new drugs for ALS," she told LiveScience.
Men in the study with moderate early balding had a 50 percent higher risk of ALS compared with men with no balding. The results showed a clear trend: with increasing levels of balding at age 45, the risk of ALS increased, the researchers said.
The results were controlled for potential risk factors of both early balding or ALS, such as smoking, weight, as well as vitamin E intake, which may protect against ALS.
What may underlie the link
One possible mechanism for a link between ALS and early balding may involve a protein called the androgen receptor, a protein that regulates the hormone testosterone and has been shown to be associated with an increased risk of early balding.
In 1980, researchers proposed the possibility that androgen receptor is involved in ALS. The idea originated when researchers observed that the disease affected all motor neurons except those that lacked the androgen receptor.
"Everybody got so excited about this theory," Fondell said. "So they tested it, but found that the androgen receptor does work," so the idea wasn't pursued further.
"I think they dropped it too early," Fondell said.
Another possible explanation could involve a genetic variation in early balding recently identified in an analysis of genetic studies of the condition. The variation is in a gene located close to another gene that has been implicated in ALS. Given the physical proximity of the two genes, it is possible that one affects the other, the researchers said.
The study was published Aug. 13 in the American Journal of Epidemiology.
Email Bahar Gholipouror follow her @alterwired. Follow LiveScience @livescience, Facebook & Google+. Original article on LiveScience.
Copyright 2013 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. ]]>
Our 2024 Coverage Needs You
It's Another Trump-Biden Showdown — And We Need Your Help
The Future Of Democracy Is At Stake
Our 2024 Coverage Needs You
Your Loyalty Means The World To Us
As Americans head to the polls in 2024, the very future of our country is at stake. At HuffPost, we believe that a free press is critical to creating well-informed voters. That's why our journalism is free for everyone, even though other newsrooms retreat behind expensive paywalls.
Our journalists will continue to cover the twists and turns during this historic presidential election. With your help, we'll bring you hard-hitting investigations, well-researched analysis and timely takes you can't find elsewhere. Reporting in this current political climate is a responsibility we do not take lightly, and we thank you for your support.
Contribute as little as $2 to keep our news free for all.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
The 2024 election is heating up, and women's rights, health care, voting rights, and the very future of democracy are all at stake. Donald Trump will face Joe Biden in the most consequential vote of our time. And HuffPost will be there, covering every twist and turn. America's future hangs in the balance. Would you consider contributing to support our journalism and keep it free for all during this critical season?
HuffPost believes news should be accessible to everyone, regardless of their ability to pay for it. We rely on readers like you to help fund our work. Any contribution you can make — even as little as $2 — goes directly toward supporting the impactful journalism that we will continue to produce this year. Thank you for being part of our story.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
It's official: Donald Trump will face Joe Biden this fall in the presidential election. As we face the most consequential presidential election of our time, HuffPost is committed to bringing you up-to-date, accurate news about the 2024 race. While other outlets have retreated behind paywalls, you can trust our news will stay free.
But we can't do it without your help. Reader funding is one of the key ways we support our newsroom. Would you consider making a donation to help fund our news during this critical time? Your contributions are vital to supporting a free press.
Contribute as little as $2 to keep our journalism free and accessible to all.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
As Americans head to the polls in 2024, the very future of our country is at stake. At HuffPost, we believe that a free press is critical to creating well-informed voters. That's why our journalism is free for everyone, even though other newsrooms retreat behind expensive paywalls.
Our journalists will continue to cover the twists and turns during this historic presidential election. With your help, we'll bring you hard-hitting investigations, well-researched analysis and timely takes you can't find elsewhere. Reporting in this current political climate is a responsibility we do not take lightly, and we thank you for your support.
Contribute as little as $2 to keep our news free for all.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
Dear HuffPost Reader
Thank you for your past contribution to HuffPost. We are sincerely grateful for readers like you who help us ensure that we can keep our journalism free for everyone.
The stakes are high this year, and our 2024 coverage could use continued support. Would you consider becoming a regular HuffPost contributor?
Dear HuffPost Reader
Thank you for your past contribution to HuffPost. We are sincerely grateful for readers like you who help us ensure that we can keep our journalism free for everyone.
The stakes are high this year, and our 2024 coverage could use continued support. If circumstances have changed since you last contributed, we hope you'll consider contributing to HuffPost once more.
Support HuffPostAlready contributed? Log in to hide these messages.