Long-term snoring can cause nerve damage in throat
People who snore can, over time, develop nerve damage in their throats. Eva Svanborg, a professor in clinical neurophysiology involved in sleep disorder research, shows how. She has documented nerve damage in patients with sleep apnoea, a condition affecting at least 200,000 Swedes and which can, among other things, increase the risk of heart attack.
It is well documented that people who work with vibrating tools over the long term often develop nerve damage in their hands. It has also been shown that rats subjected to vibrations in their hind legs develop damage in only a few weeks. Svanborg’s research group has shown that even snoring can give rise to nerve damage.
One of the studies measured how different test groups registered temperature changes in their throats. The people were divided into three groups:
- people with sleep apnoea.
The differences were striking. The non-snorers could, on average, detect a temperature difference of between one and three degrees Celsius. Among snorers the range was greater, from those who were relatively sensitive to those who barely detected a temperature difference at all.
For the group with sleep apnoea, sensitivity was consistently considerably worse.“In certain patients we could drop the temperature down towards 0°C before they thought it felt cold. This confirms my thesis that snoring can cause vibration damage in the nerves of the throat,” Svanborg says.
Besides her position as a professor of neurophysiology at the Faculty of Health Sciences , Svanborg also works as chief physician and departmental director at the neurophysiology clinic at the University Hospital in Linköping. Patients with various types of sleep disorders, for example obstructive sleep apnoea syndrome, are treated there. This is a variant of the illness that affects one out of every ten snorers and which is characterized by habitual snoring and repeated interruption of breathing, which disrupts sleep and causes severe fatigue.
The lack of oxygen that occurs can also lead to severe headaches, high blood pressure, and increased risk for heart attack and stroke. Moreover, the condition has been linked to both obesity and diabetes and, according to several studies, people with sleep apnoea are five to eight times more likely to get into traffic accidents.
Patients with at least five breathing interruptions per hour of sleep are diagnosed with sleep apnoea. But the boundaries are fluid. The condition is most critical for children.
“For older people, a large number of interruptions in breathing doesn’t need to be a cause for concern. People over 60 aren’t at increased risk for cardiovascular damage, so the question of treatment depends on how tired the patient is during the day,” Svanborg says.
Svanborg’s interest in sleep disorders came about in 1985 when she was working at the Neurophysiology Clinic at Södersjukhuset in Stockholm. The staff thought that one of the patients in intensive care was breathing oddly.
“We ran what’s called a polysomnographic test, which showed that he had suffered over 400 interruptions in his breathing that night. I’d never seen anything like it before, and thought I’d never see something like that again. But now I’ve met several thousand patients with sleep apnoea.”
Svanborg talks more about her research into sleep disorders in the Forskning i Framkant (Cutting Edge Research) lecture series under the title ‘Is Snoring Dangerous?’
“The answer to the question is no. It’s not dangerous. On the other hand, there’s a risk that snoring over the long term causes sleep apnoea, which in turn can cause a number of difficulties and serious conditions. So if you have problems with snoring and fatigue, it would be a good idea to seek help as early as possible. There’s good help available,” she says.
Treatment can be anything from a splint that makes breathing easier to what’s called a CPAP, where the patient sleeps with a mask attached to a compressor that creates a slight over-pressurisation. Losing weight, avoiding alcohol, and learning to sleep on your side usually also help. Surgery is only performed in exceptional cases. According to previous studies, approximately 70 % of all those that underwent surgery for sleep apnoea suffered a relapse.
“But for young people whose weight is normal and who have no serious conditions, an operation can be effective. We just conducted a 15-year follow-up of patients we’d operated on. Those who were cured after two years still retained normal breathing patterns at night.”
Text: Karin Allander
The lecture is on September 22 at 3:30 PM in Victoria Hall, University Hospital Campus US. It will be filmed and will be viewable on the web starting September 29.
Last updated: Mon Dec 10 13:09:53 CET 2012