What are the latest developments in snoring and sleep apnea?
There have been a number of new advances in our understanding of sleep apnea and it’s consequences. When it comes to treatment, there are promising new devices and treatment approaches, as well as some unexpected results from a key research trial in to sleep apnea treatment in people with heart problems.
What’s new in treatment?
In treating snoring one new product, ‘Mute’ has been developed by a Melbourne-based company on the back of experience using the device in athletes. The ‘Mute’ device is a device that fits in both nostrils during sleep and opens up the nose to allow greater airflow during sleep. Rhinomed, the manufacturer of the device, reports that 73% of partners reported a reduction in snoring. This research hasn’t yet been published in full so it’s not clear what effect ‘Mute’ has on sleep apnea or who is likely to get a better response. It has it’s main effect on the outer part of the nose, so I would expect those who would respond best are people who have nasal obstruction in the front of the nose. The same company has also just received ethics approval to test their new device, intra-nasal positive expiratory airway pressure (INPEAP), in 20 people with moderate obstructive sleep apnea.
There was also a symposium at the Sleep 2015 meeting in Seattle specifically on combining treatments. This is something we are doing more in practice. For example if people are using an oral appliance such as a mandibular advancement splint but have ongoing symptoms, adding other treatments such as Provent nasal valves or positional treatment can help get more out of the oral appliance without necessarily just needing to change to CPAP.
Sleep apnea and heart failure – SERVE-HF
People with heart failure, that is weakened heart muscles, commonly have sleep apnea with some studies showing sleep apnea in up to 60%. In people with heart failure, sleep apnea is a marker for higher risk, and those with sleep apnea have been shown to have a shorter life expectancy. Because of this there has been a lot of interest in treating sleep apnea in people with heart failure.
In heart failure, people get a combination of obstructive sleep apnea (OSA), where there is narrowing of the upper airway, as well as central sleep apnea (CSA), changes in the rhythm of breathing with a pattern of over-breathing then under-breathing that repeats around once a minute throughout the night. Whilst continuous positive airway pressure (CPAP) is an effective treatment for OSA, it does not generally reduce CSA. For this reason, ResMed designed and conducted a study, SERVE-HF, of a device that manages both OSA and CSA. The device is called VPAP-Adapt and is a form of adaptive-controlled servo-ventilation.
The SERVE-HF study enrolled 1,325 subjects and was stopped early as it emerged that those with severe heart failure (ejection fraction <45%) and mainly CSA had a higher risk of heart rhythm abnormalities. In those treated with VPAP-Adapt, 10% had a sudden death each year, compared to 7.5% in those not treated with VPAP-Adapt. This finding was unexpected and as the full results haven’t yet been released, so we don’t really understand why this occurred.
Given the results of the study, physicians have been advised to review all their patients being treated with VPAP-Adapt to ensure they don’t fit in to this high risk group. If you are using a VPAP-Adapt device it is worth discussing the SERVE-HF results with your physician.
Weight loss is important in managing sleep apnea
An important study that was published in the last year in the New England Journal of Medicine, looked at the role of weight loss in improving health in people with obstructive sleep apnea (OSA). The researchers compared 24 weeks of CPAP, with weight loss and CPAP and weight loss combined. Those in the weight loss arm had 2-3 liquid meal replacements per day and four weekly gym sessions. With this they lost an average of 7kg. With this weight loss, there was a significant reduction in measures of heart risk such as blood pressure and cholesterol and improvements in metabolism. Those assigned just to CPAP had improvements in sleep apnea, but didn’t get the same improvements in cholesterol and metabolism that were seen in those who lost weight.
What are the risks of sleep apnea?
Adding to the evidence that obstructive sleep apnea (OSA) increases the risk of heart problems and other cardiovascular diseases was a study from Canada that followed over 10,000 people for up to 15 years. It showed in 5 years that 16% of people with severe OSA had a heart attack, stroke, developed heart failure or died compared with 6% of people without OSA. That means that 10 more people out of every 100 with severe OSA would be expected to develop one of these serious health problems in a 5 year period compared to people without sleep apnea. Some of the factors that produced higher risk were oxygen levels being lower during sleep and the degree of daytime sleepiness.
How does sleep apnea differ in older adults?
In practice, I often find that older patients don’t do as well with treatment like oral appliances or surgery as younger patients do. Research published in 2014 in Sleep helps to explain why this might be the case. The researchers looked at 10 younger (20-40 year old) and 10 older (>60 year old) people with sleep apnea. They showed that in the older people the airway tended to collapse more, or was floppier during sleep. This means that treatments that partially open the airway such as oral appliances or surgery may not be as effective.
Diagnosing sleep apnea
Traditionally sleep studies have been done in hospitals or sleep laboratories with scientists in attendance overnight monitoring what happens and ensuring accurate recordings. However, changes in technology over the last decade have meant that sleep studies can be done at home without needing a scientist present. Sleep studies done at home are usually not as detailed as those done in a sleep laboratory, but for people who are looking to have a diagnosis of obstructive sleep apnea (OSA) confirmed, or to rule out significant sleep apnea they can be enough.
Whilst home sleep testing (HST) is increasingly used, it is generally used to confirm a diagnosis of OSA in people felt to be at high risk. Research published in Sleep looked at using HST to diagnose sleep apnea in people with a history of snoring, but not at high risk of OSA. They performed a simple HST over 3 nights at home in 56 patients and compared that to results from a sleep laboratory-based detailed sleep study. They showed that a simple HST over 3 nights at home could help differentiate those with and without significant sleep apnea. If the number of breathing changes per hour (AHI) was less than 7 on the HST, people did not have moderate or severe OSA. Whereas, when the AHI was more than 22 on the HST, it confirmed moderate or severe OSA. This shows how simple HST can be helpful, to rule in or out moderate to severe OSA, when the AHI is <7 or >22. However, for people with a HST AHI of 7-22 further testing with a sleep-laboratory based sleep study is still needed to rule in or out sleep apnea.
Related posts & links:
Need more information about how you can sleep better?
At Sleephub we understand the struggle people endure with sleeping problems which is why we have created a comprehensive FAQs page with information for those seeking information about sleep disorders and potential solutions.