The report—a review of 234 clinical studies published through 2010—finds that a CPAP machine is highly effective at improving sleep and related symptoms of OSA by improving airflow. However, the report also finds that use of a CPAP machine includes possible side effects—such as feeling trapped, dry nose and mouth, nosebleeds, and chest discomfort—that may lead patients to abandon treatment. Additionally, the report notes that the CPAP machine is effective only if it is used every night.

The report finds MADs are also effective but have possible side effects of their own, including potentially loose or damaged teeth.

The report further finds that there is not enough evidence to determine if surgery to clear airway blockage, the third major treatment for OSA, is more or less effective than nonsurgical treatments. Other treatments—including weight loss programs and medication—were also examined, but the evidence was insufficient to draw conclusions about these treatments, according to the report.

Additionally, the report looks at the evidence supporting the effectiveness of portable monitoring to diagnose OSA. The report concludes, “The strength of evidence is low that Type II monitors are accurate to diagnose OSA (as defined by PSG), but have a wide and variable bias in estimating the actual AHI.” Meanwhile, the report finds, “The strength of evidence is moderate that Type III and IV monitors are generally accurate to diagnose OSA (as defined by PSG), but have a wide and variable bias in estimating the actual AHI.” The report notes that evidence is insufficient to adequately compare specific monitors to each other.

In addition to the report, the AHRQ has also made a series of companion comparison guides available for consumers and clinicians that summarize the report’s findings. The consumer guide defines sleep apnea for patients and their families, summarizes treatment options, and offers a list of questions for patients to discuss with their doctor. The clinician guide, meanwhile, covers the same topics as the consumer guide, while also providing “confidence ratings” for existing scientific evidence and offering a “clinical bottom line” to give clinicians tools to discuss treatment options with the patients.

Source: Sleep Review

The Apnex HGNS System is an implantable therapy that is intended to work by activating the muscles in the upper airway to ensure that the airway remains open during sleep. The system detects the patient’s breathing and delivers mild stimulation to the hypoglossal nerve, the nerve that controls the muscles of the tongue, to keep the airway open.

“Many patients who suffer from OSA are unable to tolerate existing therapies such as continuous positive airway pressure (CPAP). The HGNS System provides a fundamentally new approach to the treatment of OSA. This study will help us further understand the potential role this device will have in treating the millions of people who suffer from OSA,” said the study’s co-principal investigator, Dr Atul Malhotra, clinical chief, Division of Sleep Medicine, Brigham and Women’s Hospital.

Sponsored by Apnex Medical, the Apnex Clinical Study is a prospective, randomized, multicenter clinical trial. It is being conducted in leading medical centers in the United States, Europe, and Australia. The trial is designed to demonstrate the safety and effectiveness of the HGNS therapy in treating patients with moderate to severe OSA. To be enrolled in the study, patients must not have received lasting benefit from CPAP or other OSA treatments.

“We have seen very encouraging results from the HGNS feasibility studies. Results recently presented at the international SLEEP meeting showed that most patients treated with the HGNS System experienced significant improvements in their sleep apnea, sleepiness, and quality of life. This study will help us determine if these results can be demonstrated in a second larger patient population,” said the study’s co-principal investigator, Dr Eric Kezirian, Department of Otolaryngology—Head and Neck Surgery, University of California, San Francisco.

Source: Sleep Review Mag

The findings appear online in the articles-in-press section of the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.

“In patients with obstructive sleep apnea who are established on CPAP treatment, withdrawal of the therapy is associated with a rapid recurrence of OSA and sleepiness within a few days” said Malcolm Kohler, MD, senior consultant at the Sleep Disorders Centre and Pulmonary Division of the University Hospital in Zurich. “After 14 days of CPAP withdrawal, OSA patients experienced considerable increases in heart rate and blood pressure as well as a deterioration in vascular function.”

The researchers recruited patients who had been previously diagnosed with OSA and treated with CPAP and were registered in a database of the Sleep Disorders Centre in Zurich. Patients were randomized to either continue CPAP therapy or to withdraw CPAP (maintaining a sub-therapeutic level) for two weeks. After baseline polysomnography, patients underwent nightly at-home assessment of respiration and oxygen saturation each day of the study period. Patients were also assessed for subjective and objective sleepiness, psychomotor performance, blood pressure and heart rate, endothelial function (a marker of vascular function), systemic inflammation, insulin resistance and urinary catecholamines (a marker of sympathetic nervous system activity.) The polysomnography was repeated at the end of the two-week period.

Not surprisingly, at the end of the study period there was a significant increase in apneic events, oxygen desaturations and the number of arousals during sleep. As a consequence of the recurrence of sleep-disordered breathing, subjective sleepiness increased in the CPAP withdrawal group “Withdrawal of CPAP was associated with a rapid return of sleep-disordered breathing within a few days,” said Dr. Kohler.

Importantly, endothelial function deteriorated considerably in the CPAP withdrawal group, and there was a marked increase in blood pressure and heart rate after two weeks. Additionally, the researchers found a significant increase in urinary catecholamines, hormones consistent with sympathetic nervous system activation. These findings imply that withdrawal of CPAP therapy for even a short time has a measurable negative effect on the cardiovascular system.

“We have shown that CPAP withdrawal leads to a return of OSA within the first night off CPAP,” said Dr. Kohler. “In addition to strongly suggesting that OSA patients should bring along their CPAP machines on holiday, these findings have implications for OSA research going forward. CPAP withdrawal represents a new way to investigate the physiological effects of OSA and evaluate novel treatments,” he explained.

“Many clinical trials involving OSA patients suffer for low recruitment rates of eligible participants. This study points to a simple solution that would circumvent the problem of poor recruitment and could dramatically improve both the quantity and quality of OSA research. Rather than recruiting eligible patients from the sleep laboratory or clinic the proposed approach uses databases including data from a large number of OSA patients. Thus the required number of eligible patients with specific characteristics can be recruited selectively within a short-time,” he went on. “This would allow us to improve the efficacy of randomized controlled trials in this area.”

Source: Keely Savoie, American Thoracic Society, via EurekAlert

The findings, published in the August 10, 2011 issue of the Journal of the American Medical Association, showed for the first time what sleep specialists have long suspected but hadn’t proved: that sleep apnea, also known as sleep-disordered breathing, can deprive the brain and other organs of the oxygen they need and, may, over time, trigger declines in cognitive ability.

“This is the first study to show that sleep apnea MAY lead to cognitive impairment,” said study leader Kristine Yaffe, MD, professor of psychiatry, neurology and epidemiology at UCSF and chief of geriatric psychiatry at SFVAMC. “It suggests that there is a biological connection between sleep and cognition and also suggests that treatment of sleep apnea might help prevent or delay the onset of dementia in older adults.”

“While we cannot conclude from these results that SDB causes cognitive impairment, our study suggests that it may at least be a contributing factor,” said Yaffe.

The senior author of the study is Katie Stone, PhD, of the California Pacific Medical Center Research Institute.

In people with sleep apnea, the airways leading from the lungs to the nose and mouth collapse as the individuals sleep, interfering with the ability to inhale. People with sleep apnea usually snore, sometimes loudly, and are wakened many times a night for tiny fragments of time as they gasp for air.

While previous research had found an association between sleep apnea and dementia, those studies weren’t structured to follow the impact of sleep apnea on people who had normal cognitive abilities at the onset. The strength of the new findings comes from the fact that the 298 subjects began the study without dementia or measurable cognitive impairments, allowing researchers to measure the relationship between sleep apnea and mental acuity.

These women, drawn from a larger, ongoing study examining osteoporosis in more than 10,000 women over 65, were first examined at clinics in Pittsburgh and Minneapolis and given tests that assessed their mental and cognitive abilities. Those who were found to be suffering from dementia or mild cognitive impairment at the initial assessment weren’t included in the study.

About four years later, sleep specialists came to the study subjects’ homes and monitored the women as they slept using specialized equipment that measured brain activity, heart rhythm, leg movements, airflow, breathing activity in their chest and abdomen and the oxygen content of blood as it passed through their fingers.

These instruments allowed researchers to track how often the women experienced apneas (the complete blockage or airflow) or hypopneas (a reduction of airflow of 30 percent or more) and how much time they spent in an oxygen-deprived state.

About five years after their first visit, the women returned to the clinics and were given a larger battery of tests that measured their cognitive abilities, memory and verbal fluency. The tests included the Mini-Mental State Examination, the California Learning Verbal Test and a test of executive function called Trails B.

Women whose test results suggested they had dementia or mild cognitive impairment had their records reviewed by a panel of clinical experts who decided whether to confirm the diagnosis.

When Yaffe and her colleagues tabulated the results of the study, they found that about one third (35.2 percent) of all the women developed dementia or mild cognitive impairment. They also found that those with sleep apnea were almost twice as likely to become cognitively impaired.

Among the women found to suffer from sleep-disordered breathing, 44.8 percent of them developed dementia or mild cognitive impairment, compared with 31.1 percent of those who didn’t have impaired breathing and sleep.

The findings suggest that the key factor leading to diminished cognition was oxygen deprivation, also called hypoxia. Women who had frequent episodes of low oxygen or spent a large portion of their sleep time in a state of hypoxia were more likely to develop cognitive impairment. By contrast, no independent connection was seen between dementia and the number of times patients were awakened in their struggle to breathe.

Some previous studies have suggested that providing oxygen therapy to patients with Alzheimer’s disease and sleep apnea slows their cognitive decline. The new findings suggest that providing oxygen therapy to elderly people with sleep apnea may reduce the chances of them becoming cognitively impaired or delay the onset of mental decline.

Source: Jennifer O’Brien, University of California – San Francisco, via EurekAlert

Sleep apnoea, a condition in which people stop breathing momentarily while sleeping, affects up to 20 percent of the population. The researchers found treatment with a continuous positive airway pressure (CPAP) device reduced post-meal blood fat (triglyceride) levels.

The study was conducted at the University of Sydney’s NHMRC Centre for Integrated Research and Understanding of Sleep (CIRUS) and published in the American Journal of Respiratory and Critical Care Medicine.

The researchers investigated blood fat levels across a 24-hour period after standard meals in 38 patients with sleep apnoea. Patients were studied both before and after two months of CPAP and two months with a placebo CPAP device.

“We know that blood fat levels after meals are an important predictor of future cardiovascular disease. This research provides a possible reason why patients with sleep apnoea are at increased risk of heart attacks and strokes,” said lead author Dr Craig Phillips, who holds joint appointments with CIRUS and Royal North Shore Hospital.

“Although the results need to be confirmed in larger studies, we estimate that the extent of the improvement in triglycerides with CPAP could reduce the risk for heart attack in these patients by as much as 25 percent.”

Study senior author, Professor Ron Grunstein from CIRUS, commented: “Another interesting aspect of the study was that triglyceride levels were particularly high in the middle of the night during sleep, almost seven hours after the evening meal.

“There may be an influence of the body clock that pushes up blood fat levels at these times,” he said. “If this is the case, the higher rates of cardiovascular disease in night shift workers may be caused by eating high fat meals at a time when the body can’t properly control blood fat levels.”

The researchers are currently studying this possibility using special shiftwork simulation facilities located at the University of Sydney’s Woolcock Institute.

Source: MedIndia

“We found that in patients with chronic venous insufficiency, compression stockings reduced daytime fluid accumulation in the legs, which in turn reduced the amount of fluid flowing into the neck at night, thereby reducing the number of apneas and hypopnea by more than a third,” said Stefania Redolfi, MD, of the University of Brescia in Italy, who led the research.

CVI occurs when a patient’s veins cannot pump enough oxygen-depleted blood back to the heart. It occurs most often in the veins of the legs.

The findings appear online ahead of the final publication of the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.

Continuous positive airway pressure machines, known as CPAP, are one of the only treatment options currently recommended for people with OSA. However, many find wearing a mask all night prohibitively uncomfortable, and compliance is low, resulting in many patients living with untreated OSA and its serious health consequences. Finding a more effective means of treating OSA, therefore, is a high priority.

Dr. Redolfi and colleagues sought to determine whether a simple intervention like wearing compression stockings might be effective in some OSA patients.

In active people, fluid accumulation in the legs is counteracted by leg muscle contractions that squeeze the veins. However, prolonged sitting can prevent this process, and the accumulated fluid in the legs then shifts rostrally overnight. This shift results in fluid accumulation in neck tissue and is thought to increase apneic events by increasing the volume of the tissue, leading to repetitive collapse of the pharynx during night breathing. In otherwise healthy subjects who have heart failure or hypertension, the amount of this overnight rostral fluid shift is strongly correlated with the degree of overnight increase in neck circumference and the number of apneas and hypopnea per hour of sleep.

“We hypothesized that the fluid accumulation that occurs in the legs of people with chronic venous insufficiency would be reduced by wearing compression stockings, and that the reduction in the fluid would also reduce the shift of that fluid to the neck during the night,” said Dr. Redolfi. “There is strong evidence linking that rostral shift of fluid overnight to apnea. If we could reduce that, we would expect that apneic events would likewise be reduced.”

To investigate whether compression stockings could alleviate this problem, the researchers recruited subjects from the chronic venous insufficiency clinic at La Pitié-Salpêtrière hospital in Paris. Twelve patients were randomly assigned to one week of wearing the compression stockings or to a one-week control period without compression stockings. At the end of the first week, they crossed over to the other arm of the study. Each subject underwent polysomnography and overnight changes in leg fluid volume and neck circumference were measured at baseline and at the end of the compression stockings and control periods.

At the end of the compression stocking period, subjects had an average of a 62 percent reduction in overnight leg fluid volume change as compared to when they did not wear the stockings. Patients also had a 60 percent reduction in neck circumference increase, which the researchers used as a proxy measurement to estimate fluid shift into the neck and a 36 percent reduction in the number of apneas and hypopnea per hour of sleep.

“Our findings provide proof-of-concept that among subjects with CVI, overnight rostral fluid displacement is a mechanism of disease for OSA. The effect of compression stockings on OSA is based on counteracting this fluid displacement. Prevention of dependent fluid accumulation could constitute a new therapeutic approach to OSA,” said Dr. Redolfi.

“These findings are what we expected,” she continued, “but the extent to which simply wearing compression stockings reduced apnea in just one week was not expected. It would be very interesting to see whether the wearing of the stockings over longer periods would have an even greater effect.

“Whether prevention of overnight rostral fluid displacement can attenuate OSA in other patient populations is an important issue that remains to be addressed in future studies,” she added.

Source: Keely Savoie, American Thoracic Society, via EurekAlert

Provent strips are disposable, nude-colored, one-way resister valves that adhere to both nostrils. Provent requires a prescription and has been FDA-approved for about two years, but is not commonly used by patients because it is still fairly new and sometimes not covered by insurance.

According to Dr. Amit Patel, assistant professor of medicine at Weill Cornell Medical College, anyone can be susceptible to sleep apnea. “Because it is an anatomical issue, a narrowing of the airway, the obvious patient types are people who are obese, people who have a lot of extra tissue, because that tissue can gain in the upper airway, causing a collapse. Patients who have a jaw that’s a little bit pushed back, therefore compromising the space in the back of the airway, and patients potentially with neurological diseases are at risk because what keeps the back of the airway open are muscles, so when you sleep, everything relaxes.”

Previously, Nemoga used a C-Pap, or continuous positive airway pressure machine. This apparatus works in 90 percent of patients with sleep apnea, Dr. Patel told Fox News, but can be uncomfortable and cumbersome. The C-Pap consists of a face mask, which is connected to a hose and pumps air into the patients’ nose. Although the C-Pap treated Nemoga’s sleep apnea by not allowing her airway to close, it created multiple complications in her personal life.

“My family teased me about sounding like one of the Star Wars characters [Darth Vader],” she said.

And there was another conflict: The bulky machine was difficult for Nemoga, who loves to travel, to take on the road.

“I basically have my suitcase packed and if somebody needs a companion, I’m ready to go,” she said.

A C-Pap machine is considered a carry-on item on all airplanes, meaning she could only carry a purse and her C-Pap machine when traveling, rather than an overnight bag.

Provent strips are small enough to slip into a purse or pocket, making it much easier for Nemoga to travel.

Dr. Patel told FoxNews.com that Provent strips are a great alternative to a C-Pap machine.

“In those patients that come on to the Provent device, after having really tried C-Pap, often times the first reaction is very positive,” Patel said. “The results are fantastic because it is a new device which completely eliminates the machine, a hose, a tube, and is very freeing for a lot of patients.”

Certain patients with high risk factors accompanying their sleep apnea, like hypertension or cardiovascular issues, should be prescribed C-Pap initially but can, after remedying other medical factors, transfer to the Provent, according to Patel.

Nemoga said she is thrilled with the results of switching to Provent, calling it “miraculous, simple and fabulous.”

Source: Jacqueline Tozzi, Fox News

Obstructive sleep apnea may cause changes in blood vessel function that reduces blood supply to the heart in people who are otherwise healthy, according to new research reported in Hypertension: Journal of the American Heart Association.

However, treatment with 26 weeks of continuous positive airway pressure (CPAP) improved study participants’ blood supply and function.

Obstructive sleep apnea, which causes periodic pauses in breathing during sleep, affects about 15 million adults in the United States, according to the American Heart Association. The sleep disorder may be a contributing factor to high blood pressure and cardiovascular diseases.

“The findings should change how doctors treat patients with obstructive sleep apnea,” said Gregory Y.H. Lip, M.D., lead author of the study and professor of cardiovascular medicine at the University of Birmingham in the United Kingdom. “Even apparently healthy patients with sleep apnea show abnormalities of small and large blood vessels, as well as impaired blood supply to the heart muscle, and these can improve with CPAP therapy.”

CPAP treatment provides a constant airflow that holds the airway open to maintain uninterrupted breathing during sleep. This eliminates sleep apnea events and allows the patient to get a restful sleep.

The study is the first to show blood vessel abnormalities in sleep apena patients. Previous studies have linked blood vessel dysfunction to cardiovascular disorders.

Reversing blood vessel abnormalities could help patients with obstructive sleep apnea who are otherwise healthy avoid developing and dying from cardiovascular disorders, researchers said.

Researchers looked for changes in blood vessel function in 108 participants who were otherwise healthy, with no differences in age, sex, body mass index and smoking status across three groups:

• 36 people with moderate or severe obstructive sleep apnea without high blood pressure
• 36 high blood pressure patients without obstructive sleep apnea
• 36 patients with neither high blood pressure nor obstructive sleep apnea

Researchers used several techniques to assess blood vessel function, including myocardial contrast echocardiography to check the blood supply to the heart muscle.

All the sleep apnea patients received CPAP therapy; so proper randomized studies will still be needed to confirm the intervention’s beneficial effects on the blood vessels, Lip said.

Furthermore, patients in the control groups weren’t treated with CPAP therapy, which would have been clinically unjustified because none had obstructive sleep apnea, researchers said.

Lip hopes his research will bring greater awareness to the relationship between obstructive sleep apnea and cardiovascular diseases. “The condition can be treated, and it is important that clinicians look out for it,” he said.

Source: Karen Astle, American Heart Association, via EurekAlert

Results show that several sound features of breathing were statistically significant between participants with OSA and healthy controls. In an analysis that combined the two most significant sound features, the presence or absence of OSA was predicted with more than 84% accuracy. Sound analysis also allowed for the stratification of OSA severity.

According to the authors, people with OSA tend to have a narrower and more collapsible pharynx with more negative pharyngeal pressure, which creates greater resistance when breathing through the nose. Breathing sounds are directly related to pharyngeal pressure, making sound analysis a viable diagnostic option for OSA.

“Despite being able to breathe at the same high flow rate, the pharyngeal pressure in people with OSA during wakefulness is usually more negative than that in the non-OSA group,” said principal investigator and lead author Zahra Moussavi, PhD, professor and Canada Research Chair on Biomedical Engineering at the University of Manitoba in Winnipeg, Canada.

Moussavi and co-investigator Aman Montazeri studied 35 patients with varying severity levels of OSA and 17 age-matched controls. The presence or absence of OSA was validated by full-night polysomnography.

The subjects were instructed to breathe through their nose at their normal breathing level for at least five breaths and then breathe at their maximum flow level for another five breaths. Then the process was repeated as they breathed through their mouth with a nose clip in place. The breathing sounds were picked up by a microphone placed over the neck, and the recordings were repeated in two body positions: sitting upright and lying on the back. Data were digitized and then analyzed using spectral and waveform fractal dimension techniques.

Moussavi added that detecting OSA through sound analysis could become an attractive alternative to the more costly and labor-intensive method of performing overnight polysomnography.

Source: Sleep Review Mag

Approximately 60% to 70% of patients with sleep apnea are either overweight or obese. Previous studies in other patient groups have concluded that losing weight can improve the condition.

The authors, led by Kari Johansson from the Karolinska Institute in Stockholm, investigated whether a low energy diet followed by counseling to keep weight under control benefited patients with sleep apnea.

The study follows a previous trial by the same authors, published in the British Medical Journal in 2009, that investigated the effects of a very low energy diet for 9 weeks. The most recent study looks at the longer term effects of weight maintenance over 1 year.

The study included 63 men between 30 and 65 years of age who had moderate to severe obstructive sleep apnea. The participants had a body mass index (BMI) range of 30-40.

Of the 63 patients, 58 followed a very low energy diet for 9 weeks and then started a 1-year weight maintenance program (this included counseling and advice about nutrition and exercise). The very low energy diet was based on the Cambridge weight plan.

The results show that patients who lost weight after 9 weeks on the low energy diet maintained the loss after a year, and this had a positive effect on their sleep apnea. For instance, at 1 year, 48% of patients no longer required CPAP and 10% had total remission of obstructive sleep apnea.

Patients who had severe forms of the disease at the beginning of the study had larger improvement than those with moderate disease, says the study. The authors also found that patients who lost the most weight improved the most.

Source: Sleep Review Mag