Monday August 19 2013
It is estimated that 40% of the UK adult population snores
"Could singing stop snoring? Doctor says vocal exercises could be the key to a peaceful night's sleep," the Mail Online website reports after a study found that people who followed a daily exercise programme of singing saw improvements in their snoring.
The news is based on a trial comparing the effects of daily singing exercises with not singing in 127 people with a history of snoring or mild to moderate sleep apnoea. Sleep apnoea is a condition where a person's breathing is interrupted in their sleep. This prevents them from falling into a deep sleep, leading to excessive daytime sleepiness.
The study found that those who did the singing exercises for three months reported less daytime sleepiness and less frequent snoring than those who didn't.
But the study's results are limited by the number of people who dropped out. Among the singing group, 40% of the people assigned to the group did not complete their final assessments, with 14% of the control group dropping out. It is possible that the dropouts' performance may have had a significant impact on the study's final results.
Overall, these results show preliminary evidence that regular singing exercises may benefit people who snore or have mild to moderate sleep apnoea. The effect of singing on breathing at night would ideally need to be further established by larger studies using detailed sleep monitoring.
Where did the story come from?
The study was carried out by researchers from the Royal Devon and Exeter NHS Foundation Trust. The study did not have any funding, but the CDs the participants used to perform the singing exercises were provided by the local singing teacher who developed them.
It was published in the peer-reviewed International Journal of Otolaryngology and Head and Neck Surgery. The journal is open access, so it is possible to read the complete study free of charge.
The story was covered reasonably well by the Mail Online. Both the media and the study's authors report that although the severity of snoring was improved, the difference was not big enough to be considered robust evidence that singing can help improve snoring.
As the researchers point out, the effects ideally need to be confirmed in a sleep centre where a number of devices can be used to monitor the participants' quality of sleep and breathing. The researchers could not do this as part of the current study as they did not have enough funding.
What kind of research was this?
This was a randomised controlled trial (RCT) looking at the effect of regular singing exercises on the symptoms of sleep apnoea and snoring. The two conditions are caused by resistance to air flow in the upper airways. Snoring can be a symptom of sleep apnoea, but not all people who snore have the condition.
The main treatments for both snoring and mild sleep apnoea are lifestyle changes, including weight loss, stopping smoking and limiting alcohol intake, particularly before sleeping. There are also anti-snoring nasal devices and dental appliances that can be worn at night.
A treatment called continuous positive airway pressure (CPAP) is sometimes used to treat moderate to severe sleep apnoea, which involves being attached to a breathing apparatus at night. In rare cases, surgery may also be used for severe snoring or severe sleep apnoea.
The current study was prompted by the observations of a local singing teacher, who felt that some people having formal singing training reported reduced snoring and improved sleep.
The researchers thought this could be because singing training improved muscle tone in the upper airways. They wanted to formally test whether regular singing exercises would improve snoring in an RCT, as this is the best way of testing the effects of a treatment.
What did the research involve?
The researchers recruited 127 adults who presented to their Otolaryngology (ENT) department with snoring only (72 people) or mild to moderate sleep apnoea (55 people). The participants were randomised to singing exercises or no singing, and the effect on their daytime sleepiness and snoring was assessed three months later.
People with severe sleep apnoea or morbid obesity (a body mass index greater than 40) were excluded, as were those who were already using a treatment for sleep apnoea called CPAP. All participants were given general advice about optimising their body weight and reducing evening alcohol and sedative use, as these can worsen symptoms.
The singing group received a set of three CDs of singing exercises called "Singing for Snorers". They were asked to spend at least 20 minutes a day on the exercises for three months. The singing teacher who developed the exercises called each participant four to six weeks into the programme to offer support and answer any questions.
The control group received no CDs or instruction other than general advice, but were called by a researcher at four to six weeks to check on their general progress. The control group were also given the singing CDs after the study was finished so that they could try the intervention if they wanted to.
At three months the participants filled out the Epworth Sleepiness Scale, a standard questionnaire about their daytime sleepiness. Scores on this scale range from 0 to 24, with a higher score indicating more daytime sleepiness. They also rated their quality of life, and the participants or their partners reported on their snoring loudness and frequency.
Participants in the singing group reported how often they did their singing exercises on a scale from 0 (never) to 10 (every day). Researchers assessing the scores did not know who had been assigned to the singing group or control group.
What were the basic results?
Of the 127 participants, only 93 (73%) had complete data available. More people were lost from the singing group (25 people, 40%) than the control group (9 people, 14%). In the singing group, participants rated how often they did their exercises on average as 6.6 (median) on a scale from 0 (never) to 10 (every day).
Singing exercises significantly improved daytime sleepiness compared with no singing. On the Epworth Sleepiness Scale, the singing group had scores that were 2.5 points lower on average than the control group.
The singing group also snored significantly less frequently, scoring 1.5 points less on average on a 10-point scale of snoring frequency. However, there was no significant difference between the groups in the loudness of their snoring or in their quality of life.
There was no significant difference in results between patients who snored and those with sleep apnoea. Participants did not report any side effects associated with singing.
How did the researchers interpret the results?
The researchers concluded that improving the tone and strength of pharyngeal (throat) muscles with a three-month programme of daily singing exercises reduced snoring and improved symptoms of mild to moderate sleep apnoea.
This study suggests that regular singing exercises may reduce daytime sleepiness and snoring frequency in people who snore or have mild to moderate sleep apnoea. The fact that the study was an RCT increases confidence in the results, but there are some limitations.
The main limitations are the small size of the study, the loss of participants to follow-up, and the fact that the participants could not be blinded to the treatment they were receiving because of the nature of the study.
- As participants weren't blinded, their views on the likely effects of the singing could influence their self-rated results. However, if this were the case, all measures might be expected to improve in the singing group, which was not the case.
- The singing group had a high loss to follow-up (40%), a loss that was higher than the control group (14%). If all participants had been followed up and assessed, this might have given different results.
- The study only used self- or partner-reported outcomes. Although the sleepiness measure used is an accepted way of assessing the impact of sleep apnoea, the impact of singing would ideally be confirmed by sleep studies that could give an objective measure of the flow of air in the airways overnight. Such assessments are costly and could not be carried out in the current study.
- Although there were improvements in sleepiness, this did not lead to significant improvements in quality of life.
Overall, these results give preliminary evidence that regular singing exercises may help people who snore or have mild to moderate sleep apnoea. The effects of singing would ideally be confirmed in larger studies that look at people who snore and those with sleep apnoea separately, using sleep studies to confirm subjective reports of improvement.
If such studies confirmed these results, it would prove that singing could provide another non-invasive way of reducing the symptoms of sleep apnoea or snoring.
Regular singing has no known side effects and has also been used to help people with other respiratory conditions, such as severe asthma or chronic obstructive pulmonary disease (COPD).
Read more about the benefits of singing.
Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.