Category: Obstructive Sleep Apnea

Daytime functional impairments in older men with obstructive sleep apnea (OSA) are largely explained by total sleep time rather than OSA severity, according to a new study.

A modest link between OSA severity and daytime sleepiness, measured by the Epworth Sleepiness Scale, was no longer statistically significant after controlling for total sleep time. Neither sleep disturbances, measured by the Pittsburgh Sleep Quality Index, nor sleep-related quality of life, measure by the Functional Outcome of Sleep Questionnaire, were associated with OSA severity; all three measures were modestly associated with total sleep time.

According to lead author Dr. Eric J. Kezirian, director of the division of sleep surgery in the department of otolaryngology at the University of California in San Francisco, the study shows that the functional consequences of OSA in older men may differ from those in younger populations and may need to be measured with instruments designed specifically for the demographic.

"While the disorder is associated with behavioral and health-related effects that improve with treatment in young and middle-aged adults, there is little evidence concerning its adverse consequences or treatment benefits in older adults," said Kezirian. "This study showed that in a community-dwelling group of older men, the severity of OSA was not associated with daytime sleepiness, sleep symptoms, or sleep-related quality of life, after controlling for sleep duration."

Data were collected from 2,849 men with a mean age of 76.4 years. Thirteen percent (365/2849) of participants had an ESS of at least 10, a level commonly considered to be excessive sleepiness. The presence and severity of OSA were measured by in-home polysomnography. Overall the study group demonstrated mild to moderate OSA with an average apnea-hypopnea index (AHI) of 17.0. Forty-three percent had an AHI of 15 or more.

Average total sleep time was measured by actigraphy over multiple nights. Thirty-one percent (889/2849) had a short sleep time of less than 360 minutes per night, and the prevalence of short sleep time increased with AHI. Individuals with higher AHI levels also were slightly older than men with lower AHI levels, and they had a higher body mass index, poorer self-reported health status and a higher Geriatric Depression Scale score.

Keizirian said that having a better understanding of OSA in older adults will help medical professionals treat the condition more effectively.

According to the American Academy of Sleep Medicine, OSA is a sleep-related breathing disorder that involves a decrease or complete halt in airflow despite an ongoing effort to breathe. It occurs when the muscles relax during sleep, causing soft tissue in the back of the throat to collapse and block the upper airway. This leads to partial reductions (hypopneas) and complete pauses (apneas) in breathing that can produce abrupt reductions in blood oxygen saturation. Brief arousals from sleep restore normal breathing but can cause a fragmented quality of sleep. Most people with sleep apnea snore loudly and frequently, and they often experience excessive daytime sleepiness.

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Journal Reference:

1. . Behavioral Correlates of Sleep-Disordered Breathing in Older Men. Sleep, Feb 1, 2009

Obstructive sleep apnea decreases blood flow to the brain, elevates blood pressure within the brain and eventually harms the brain’s ability to modulate these changes and prevent damage to itself, according to a new study published by The American Physiological Society. The findings may help explain why people with sleep apnea are more likely to suffer strokes and to die in their sleep.

Sleep apnea is the most commonly diagnosed condition amongst sleep-related breathing disorders and can lead to debilitating and sometimes fatal consequences for the 18 million Americans who have been diagnosed with the disorder. This study identifies a mechanism behind stroke in these patients.

The study, “Impaired cerebral autoregulation in obstructive sleep apnea” was carried out by Fred Urbano, Francoise Roux, Joseph Schindler and Vahid Mohsenin, all of the Yale University School of Medicine in New Haven, Connecticut. It appears in the current issue of the Journal of Applied Physiology.

During sleep apnea episodes, the upper airway becomes blocked, hindering or stopping breathing and causing blood oxygen levels to drop and blood pressure to rise. The person eventually awakens and begins breathing, restoring normal blood oxygen and blood flow to the brain.

Ordinarily, the brain regulates its blood flow to meet its own metabolic needs, even in the face of changes in blood pressure — a process known as cerebral autoregulation. This study found that the repeated surges and drops in blood pressure and blood flow during numerous apnea episodes each night reduces the brain’s ability to regulate these functions.

Condition a health risk

Up to 4% of the population suffers from obstructive sleep apnea. In a previous study, Dr. Mohsenin and his colleagues showed that people with sleep apnea are three times more likely to suffer a stroke or die, compared to people in a similar state of health but without sleep apnea.

“After we found that sleep apnea is a risk factor for stroke and death, independent of other risk factors, we hypothesized that there must be something wrong with the regulation of blood flow to the brain,” Dr. Mohsenin said. Participants included people with severe sleep apnea who experienced more than 30 apneas an hour during sleep time. The participants were about 47 years old, were free of cardiac disease and had not experienced any strokes. The study also included a control group which did not have sleep apnea but was similar in most other ways.

The researchers monitored the participants’ blood pressure while standing and squatting. Standing from a squatting position lowers blood pressure as can be experienced during normal daily activity. They also monitored the participants as they slept. The study found that the sleep apnea group:

• had lower cerebral blood flow velocity
• had significantly lower blood oxygen levels during sleep
• took longer to recover from a drop in blood pressure
• took longer to normalize blood flow to the brain
• Identification is key

Overall, the findings indicate that repeated surges and drops in blood pressure and low oxygen levels eventually impair the body’s ability to regulate blood flow to the brain. Sleep apnea may occur over a long period of time before the person becomes aware of it and seeks medical treatment. Here are the symptoms Dr. Mohsenin says to watch out for:

• After eight hours of sleep, you don’t feel rested. During the day, you feel more and more tired, and by afternoon, you want to nap.
• You experience loud, habitual snoring that disturbs others.
• Your bed partner observes pauses in your breathing.

The treatment of obstructive sleep apnea with an airway pressurization mask has been shown to normalize cerebral autoregulation, although there are not yet any studies to show that it reduces the rate of stroke. Those who are being treated for sleep apnea should remain compliant with treatments, according to Dr. Mohsenin, including use of

• air pressurization mask or CPAP
• nasal inserts
• dental appliances
• weight reduction for the obese

In some cases, surgery may be advised.

A new study demonstrates that the frequent arousals from sleep that occur in heart failure patients with central sleep apnea (CSA) may reflect the presence of another underlying arousal disorder rather than being a defensive mechanism to terminate apneas.

Principal investigator, Douglas Bradley, professor of medicine at the University of Toronto said that researchers involved in the study were surprised that using CPAP to alleviate CSA had no effect on arousals and no effect on sleep structure.

Bradley said, "These results indicate that unlike OSA, arousals from sleep in CSA are not protective, but probably have the opposite effect: they appear to be causative. This finding suggests that future studies should explore preventing arousals from sleep in order to treat CSA."

Results indicate that after three months of treatment with continuous positive airway pressure (CPAP) therapy, heart failure patients with CSA show no significant improvement in the frequency of their arousals or in their sleep structure even though breathing pauses are significantly reduced by 55 percent from 35.4 central apneas and hypopneas per hour to 16.1 events per hour. Arousals remain high (24.3 arousals per hour on CPAP compared to 28.8 at baseline), total sleep time stays the same at 318 minutes, and sleep efficiency remains low at 70 percent.

Data were analyzed from 205 heart failure patients with CSA who were enrolled in the Canadian Continuous Positive Airway Pressure for Patients with Central Sleep Apnea and Heart Failure trial, a prospective, randomized, multicenter clinical trial. Participants were between 18 and 79 years of age, and they were randomly assigned to a CPAP treatment group (97 members) or a control group (108 members). CSA was defined as an apnea-hypopnea index (AHI) of 15 or more with more than 50 percent of apneas and hypopneas central in nature. Members of both groups were assessed by overnight polysomnography at baseline and again after three months. Participants in the treatment group were instructed to use CPAP nightly for six or more hours, and their actual usage time was 4.6 hours per day.

According to the authors, arousals in patients with obstructive sleep apnea (OSA) are considered to be an important defense mechanism to terminate apneas, and treating OSA with CPAP immediately reduces the frequency of arousals. In contrast, arousals in heart failure patients with CSA often occur several breaths after apnea termination.

The authors suggest that hear failure patients with CSA may have a "predisposition to hyperarousability," and in some there may be an underlying arousal disorder accompanied by sleep disruption that is neither a consequence of CSA nor of impaired cardiac function. In heart failure patients with CSA, arousal from sleep may be incidental to, or play a causative role in, the development of CSA by rendering the respiratory control system unstable. Thus factors other than sleep apnea such as pulmonary congestion during the night, other comorbidities, or medications, may explain the frequent arousals that heart failure patients experience.

According to the American Academy of Sleep Medicine, central sleep apnea involves recurrent breathing pauses that occur during sleep with no associated breathing effort. A form of central sleep apnea, Cheyne Stokes breathing pattern, is most common in men over the age of 60 who have had heart failure or a stroke.

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Journal Reference:

1. . Effect of continuous positive airway pressure on sleep structure in heart failure patients with central sleep apnea. Sleep, Jan. 1, 2009

A new study suggests that screening type 2 diabetes patients for obstructive sleep apnea (OSA) and treating those who have OSA with continuous positive airway pressure (CPAP) therapy could improve the management of their hyperglycemia and might favorably influence their long-term prognosis.

Results show that in a group of 20 type 2 diabetics who were mostly obese and were newly diagnosed with OSA, sleeping and nocturnal hyperglycemia were reduced and the sleeping interstitial glucose level was less variable during CPAP treatment. The average glucose level during sleep decreased by approximately 20 mg/dl after an average of 41 days of CPAP. The sleeping glucose also was more stable after treatment, with the median standard deviation decreasing from 20.0 to 13.0 and the mean difference between maximum and minimum values decreasing from 88 to 57.

According to Arthur Dawson, MD, senior consultant in the Division of Chest and Critical Care Medicine and co-director of research at Scripps Clinic Sleep Center in La Jolla, Calif., it is not surprising that many diabetics have sleep apnea since type 2 diabetes and OSA are both conditions that are becoming much more common because of the obesity epidemic.

Dawson said, "The low blood oxygen level and the arousals associated with an apneic event activate the sympathetic nervous system and cause the release of stress hormones, both of which tend to raise the blood glucose. If we could prevent these apneic events with CPAP then we might keep the glucose level lower and more stable through the night."

According to the authors, population surveys, the Wisconsin Sleep Cohort and the Sleep Heart Health Study estimate the prevalence of type 2 diabetes in patients with OSA to be about 15 percent. OSA is associated with increased insulin resistance independent of obesity; 50 percent of patients with OSA have type 2 diabetes or impaired carbohydrate metabolism.

Twenty patients with type 2 diabetes who were on a stable diabetic regime were recruited at the time of their initial consultation with a sleep physician. All participants were newly diagnosed with moderate to severe OSA, and none had any previous experience with CPAP. Glucose level was monitored with a continuous glucose monitoring system (CGMS) over a period of 36 hours, which included a night in a sleep laboratory for evaluation by polysmnography. On the first night of the study, patients' OSA was untreated. A second night of glucose monitoring and sleep recording was done after the participants had been on CPAP therapy for a duration of one-to-three months. No changes were made in participants' diets or medication for diabetes throughout the study.

The authors report that previous studies have shown that variability of the glucose level increases the risk of eye complications and death in type 2 diabetics. Dawson said that the authors believe that recognizing and treating sleep apnea could improve the outlook for diabetics who also suffer from OSA. Researchers involved in this study theorized that by using the CGMS they were able to pick up short-term changes in the glucose level that would not be detected by traditional measurements.

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Journal Reference:

1. . CPAP Therapy of Obstructive Sleep Apnea in Type 2 diabetics Improves Glycemic Control during Sleep. Journal of Clinical Sleep Medicine, Dec 15, 2008

A new study shows that objectively measured snoring intensity is correlated with subjective sleepiness independent of the apnea-hypopnea index (AHI) in patients with moderate to severe obstructive sleep apnea (OSA).

Results indicate that the sound intensity of objectively measured snoring in patients with OSA is independently correlated with subjective sleepiness as measured by the Epworth Sleepiness Scale (ESS), and subjective sleepiness is better explained by snoring intensity than by AHI. Independent variables such as snoring intensity, desaturation severity, daily sleep time, subjective snoring frequency and nasal obstruction symptoms accounted for 22 percent of the variance in ESS scores. Snoring intensity and AHI together, however, could explain only 15 percent of the variance in ESS scores.

Principal investigator Hiroshi Nakano, MD, PhD, of the department of pulmonology at the Fukuoka National Hospital in Fukuoka, Japan, says that the results of the study indicate that daytime sleepiness is affected not only by the severity of OSA, but also by the loudness of snoring.

"The results were not so surprising, because previous studies in general population have shown an independent relationship between the degree of snoring, by a questionnaire, and sleepiness," said Nakano.

Records of 507 patients who were referred to Fukuoka National Hospital for suspected OSA and who underwent diagnostic polysomnography (PSG) between September 2002 and January 2005 were retrospectively reviewed. Subjective sleepiness was assessed using the ESS, and snoring intensity was assessed using the highest one percentile ambient sound-pressure level attained while asleep during PSG.

Patients were placed into groups of non-to-mild OSA (AHI less than 15) and moderate-to-severe OSA (AHI greater than 15) in order to clarify the effect of OSA severity on the relationship between snoring intensity and sleepiness in subsequent analyses.

Findings suggest that snoring intensity is significantly correlated with age, body mass index (BMI) and AHI. Insufficient sleep in daily life was taken into consideration as a possible cofounder, as it may enhance snoring intensity and sleepiness. Although sleepiness is one of the most important symptoms of OSA, the authors report that the correlation between the degree of sleepiness and the severity of OSA has been found to be relatively weak in many studies.

Because objectively measured snoring is related to sleepiness independent of OSA, the authors conclude that quantitative measurements of snoring are desirable in ordinary sleep studies.

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Journal Reference:

1. . Relationship between Snoring Sound Intensity and Sleeplessness in Patients with Obstructive Sleep Apnea. Journal of Clinical Sleep Medicine, Dec. 15, 2008

Continuous positive airway pressure (CPAP) treatment seems to improve cognitive functioning in patients with Alzheimer's disease who also suffer from obstructive sleep apnea, according to the results of a randomized clinical trial conducted at the University of California, San Diego.

The study – led by Sonia Ancoli-Israel, Ph.D., professor of psychiatry at the UC San Diego School of Medicine and one of the nation's preeminent experts in the field of sleep disorders and sleep research in aging populations – was published in the November issue of the Journal of the American Geriatric Society.

The research team, including physicians from UC San Diego's departments of psychiatry, medicine, neurosciences and family and preventive medicine, and Veteran's Affairs San Diego Healthcare System, looked at 52 men and women with mild to moderate Alzheimer's disease and obstructive sleep apnea (OSA). OSA is a breathing disorder characterized by brief interruptions of breathing during sleep, caused by a temporary, partial, or complete blockage in the airway. The prevalence of OSA in patients with dementia has been estimated to be as high as 70 to 80 percent.

"Although it is unlikely that OSA causes dementia, the lowered oxygen levels and sleep fragmentation associated with OSA might worsen cognitive function," said Ancoli-Israel. "This study, which showed significant improvement in patients' neurological test scores after treatment with CPAP, suggests that clinicians who treat patients with Alzheimer's disease and sleep apnea should consider implementing CPAP treatment."

"Any intervention that improves cognition in patients with Alzheimer's disease is likely to result in greater independence for the patient and less burden on their caretakers," said co-author Jody Corey-Bloom, M.D., Ph.D., professor of neurosciences at UC San Diego and research at UCSD's Shiley-Marcos Alzheimer's Disease Research Center. She added that earlier results from the same study – published in the Journal of the American Geriatric Society in 2006 – had shown that CPAP also reduced daytime sleepiness, a common complaint of Alzheimer's patients and their caregivers.

A CPAP machine is a breathing assist device worn over the mouth or nose, providing constant pressurized air and giving nighttime relief for individuals who suffer from sleep apnea. Participants were randomized to either therapeutic CPAP for six weeks, or a placebo CPAP for three weeks followed by therapeutic CPAP for an additional three weeks. Both groups received a complete battery of neuropsychological tests before treatment, at three and at six weeks.

A comparison of the randomized subjects receiving therapy over the first three-week period did not result in a statistically significant improvement in cognition, although all measures changed in the expected directions. However, after the placebo group was switched to therapeutic CPAP treatment, the group as a whole showed a significant improvement in cognition after three weeks of treatment.

Ancoli-Israel explained the discrepancy, stating that because of the smaller size of the first group of subjects – the half measured after three weeks on the therapy – a statistically significant difference couldn't be shown. However, when the before-CPAP scores of the entire group of Alzheimer patients were compared to post-therapy scores, the larger sample size demonstrated improved cognition.

"The change in scores for individual tests suggested improvements in verbal learning and memory as well as some aspects of executive function such as cognitive flexibility and mental processing speed," said Ancoli-Israel.

A relationship between symptoms of OSA and cognitive impairment has been identified in normal adults as well as in patients with dementia. According to the study's authors, most past studies examining the effect of CPAP on OSA in patients without dementia have reported improvements in cognition.

In a report published in the American Journal of Geriatric Psychiatry in February 2006 by these researchers, examining 30 patients with Alzheimer's disease and OSA, showed they were able to tolerate and adhere to the CPAP therapy. A fourth study by the research group, published in 2006 in the journal Behavioral Sleep Medicine, showed that elderly patients with dementia – particularly Alzheimer's disease – suffered more severe symptoms from sleep apnea, such as frequent awakenings, than OSA patients without dementia.

"The severity of these sleep disruptions may parallel the decline in cognitive functioning seen in elderly patients with Alzheimer's disease," said Ancoli-Israel. "While CPAP by no means treats the underlying cause of Alzheimer's disease, by improving patients' sleep patterns, the hope is that their overall cognitive functioning can also improve."

 A new study shows that unrelated to obesity, people with severe SDBs consume a more unhealthy diet, which may be a factor contributing to greater cardiovascular morbidity and mortality. These findings were most evident among women.

Stuart Quan, MD, division of sleep medicine at Harvard Medical School, said, "We found that persons who had severe obstructive sleep apnea ate a diet that was unhealthy with increased intake of cholesterol, fat and saturated fatty acids."

Findings showed that, on average, all participants with extremely severe SDB, or those with respiratory disturbance index (RDI) above 50 disruptions per hour, consumed 88.16 more milligrams of cholesterol per day compared to people who have less severe OSA. On average, women participants with severe SDB consumed 21.96 more grams of protein, 27.75 more grams of total fat and 9.24 more grams of saturated fatty acids. These results remained significant after controlling for BMI, age and daytime sleepiness.

Results indicated that among the 320 participants, increasing RDI severity was associated with greater consumption of cholesterol, protein and trans-fatty acids. There also was a trend towards greater ingestion of total saturated fatty acids and total fat, but not carbohydrates, sucrose or dietary fiber. With the exception of cholesterol, these associations occurred primarily in women. The mechanism producing the higher dietary consumption of unhealthy nutrients in persons with extremely severe SDB appears to exaggerate behaviors already observed among obese women.

Compared with the 2005 U.S. Dietary Guidelines, participants "ate less than the recommended proportion of calories from carbohydrate and more than recommended from total and saturated fat."

It is unlikely that sleep deprivation or obesity explain the results of the study. It has been suggested that fatigue and sleepiness, as well as sleep deprivation influence dietary intake via alterations in neuroendocrine control of feeding behavior; however, controlling for Epworth Sleepiness Scale score did little to affect our results and in bivariate analysis, total sleep time was not associated with alterations in dietary intake.

According to Quan, the physical activities findings in the study were unexpected. "All of us suspect that patients with sleep apnea engage in less recreational activity. This was confirmed in the study," said Quan. "However, the findings were explained entirely by obesity. We thought that because sleep apnea patients are sleepy they would engage in less physical activity even after accounting for the effect of obesity."

It is well known that obese people are more likely to consume diets high in fat and cholesterol. The persistence of these results even after controlling for BMI suggests that a high RDI has an independent effect on dietary intake. Researchers of this study suggest that independent of sleep duration, OSA may affect levels of appetite-regulating hormones. Also, sleep disruptions related to OSA may in some way increase the craving for fatty foods.

Obstructive sleep apnea, (OSA), which is a form of SDB is characterized by repetitive episodes of complete or partial airway obstruction during sleep is currently estimated to affect 18 million Americans. OSA is associated with alterations in leptin and ghrelin, which are important in appetite regulation. It has been demonstrated that sleep deprivation, a common occurrence among people with OSA, is associated with increased body max index (BMI) and increased cravings for carbohydrates. The change in hormones results in leaves that may increase appetite and thus impact dietary intake.

To investigate the relationships between dietary intake, physical activity, OSA, sleep and obesity, the study used data from a subset of the Apnea Positive Pressure Long-Term Efficacy Study (APPLES), a randomized, double-blinded, two-arm, sham-controlled, multicenter, six-month, intent-to-treat study of continuous positive airway (CPAP) efficacy on neurocognitive function in OSA.

The study included 320 participants – 263 from the University of Tucson in Arizona and 57 from the St. Mary Medical Center in Walla Walla, Washington. More than half of the participants were obese. In addition to receiving polysomnography (PSG) studies and neurocognitive assessment, participants were asked to complete detailed dietary and physical activity questionnaires prior to the initial diagnostic PSG and at the end of the four-month clinical APPLES examinations.

Poor sleep quality, a consequence of OSA, is associated with fatigue and sleepiness, which may curtail physical activity; low sleep quality may also result in a compensatory increase in caloric intake in an effort to boost energy levels, both of which promote weight gain. This study provides important new information on the dietary habits of people with OSA, which may be another mechanism through which SDB leads to serious health conditions such as cardiovascular disease, hypertension and stroke. Based on the study's findings, unhealthy dietary and activity patterns warrant further study of their role in cardiovascular and metabolic syndrome development in patients with OSA.

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Journal Reference:

1. . Associations of Dietary Intake and Physical Activity with Sleep Disordered Breathing in the Apnea Positive Pressure Long-Term Efficacy Study (APPLES). Journal of Clinical Sleep Medicine, October 15, 2008

— About two-thirds of children with sleep-disordered breathing (SDB)— snoring or obstructive sleep apnea (OSA)— have some degree of cognitive deficit, but the severity of the cognitive deficit has been notoriously difficult to correlate to the severity of the SDB, suggesting that other important issues may be at play, or that the right factors were simply not being measured.

A new study that will be published in the first issue for November of the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine opens the door to understanding the complex relationship between sleep, breathing and brain function in a whole new way.

"A history of snoring is a predictor for cognitive deficit in children with SDB," said principle investigator Raouf Amin, M.D., professor of pediatrics and the director of the Division of Pulmonary Medicine at Cincinnati Children's Hospital Medical Center. "However, the frequency of apnea events during sleep does not predict cognitive deficit and does not correlate with the degree of cognitive deficit. Such a paradox raised the question of whether there are some variables that we do not traditionally measure in the sleep laboratory that might modify the effect of SDB on cognition."

Dr. Amin and colleagues measured a new parameter to determine whether it could explain the variability in cognitive dysfunction better than the severity of SDB: the degree to which the brain's blood remains oxygenated during sleep. Using a technology called near infrared spectroscopy, which is able to penetrate the skull with high-powered light beams to assess oxygen saturation, they measured the "regional cerebral oxygen concentration" (SrO2) in children 7 to 13 years old with SDB to varying degrees. They also measured blood pressure (BP) during sleep.

As expected, they found that children with snoring had lower regional cerebral oxygen concentration than healthy children. But, paradoxically, they found that children with sleep apnea, which is usually considered a more severe degree of sleep-disordered breathing, have higher regional cerebral oxygen concentration than children with just snoring.

"During normal sleep, when breathing appears to be stable, there seems to be higher oxygen in the brain among children with sleep apnea compared even to normal children," said Dr. Amin, who attributes the unexpected finding to the sleep apnea raises blood pressure. "Children with sleep apnea have higher BP compared to children with snoring. This may explain why paradoxically we find higher oxygen levels in children with OSA."

This study opens the door to a new area of study, said David Gozal, M.D., professor of pediatrics and director of the Kosair Children's Hospital Research Institute at the University of Louisville, who wrote the accompanying editorial in the journal. "It shows us that what is happening in children with OSA and that neurocognitive deficits are not just in the brain matter but involve the cardiovascular system as well."

More than anything, the study opens up avenues of inquiry for investigating the perplexing link between SDB and cognitive deficits in children. Understanding the source of that association will be key in future efforts to treat or prevent it.

"By taking into account the role of blood pressure in regulating the amount of oxygen concentration in the brain, we might have a better understanding of the relationship between sleep-disordered breathing and cognitive deficit," concluded Dr. Amin.

For some, a full night’s rest can be anything but restful. That’s because they have sleep apnea, which causes them to struggle for breath in bouts throughout the night. Six percent of the population is affected by the condition—but many don’t even know they have it.

“They don’t make the connection between the fact that they snore loudly at night and they complain about being tired during the day,” says Samuel Krachman, D.O. , professor of medicine and director of the Sleep Disorders Center at Temple University School of Medicine and Hospital. “They think that they’re just tired, not getting enough sleep or just working too hard. But in reality, it’s related to the sleep apnea.”

Krachman is leading research on an experimental device to help patients who suffer from positional sleep apnea. Positional sleep apnea refers to patients who have episodes where they stop breathing when they’re on their back, but when they are on their side, the abnormal breathing resolves. Fifty percent of patients with mild sleep apnea (those who experience anywhere from five to 15 events an hour) and 20 percent of people with moderate sleep apnea (15 to 30 events an hour) have positional sleep apnea. Krachman explains how wearing the device, called Zzoma, works to reduce those episodes.

“Zzoma is a device which is worn around the chest area like a belt, with a device on the back, which is a firm, foam material wrapped in canvas to keep them from moving on their backs. Over the last year, we’ve been studying its use in treating patients with mild to moderate positional sleep apnea.”

The device was created by former Temple Fellow Joseph G. Crocetti. He and Krachman have worked together to treat positional sleep apnea. Their research has shown that the Zzoma device is less obtrusive and easier to use than the leading alternative, a continuous positive airway pressure machine or CPAP, a mask that blows air on a person’s face to keep the airway open.

“Although CPAP is very effective, the best studies have shown it’s only used correctly 50 percent of the time,” says Krachman. “That leaves many diagnosed with sleep apnea but not treated.”

Untreated sleep apnea can lead to a host of other medical problems. Just having sleep apnea is an independent risk factor for developing high blood pressure, coronary disease and heart failure. That’s why Krachman hopes the FDA approves Zzoma to treat positional sleep apnea, to give sufferers an effective alternative to the burden of CPAP.

A small, portable device used for the home diagnosis of obstructive sleep apnea has been deemed very reliable, according to new research presented at the 2008 American Academy of Otolaryngology-Head and Neck Surgery Foundation (AAO-HNSF) Annual Meeting & OTO EXPO, in Chicago, IL.*

According to the study, authored by researchers with the New York Otolaryngology group, 120 patients over a four-month period used Holter oximeters for home sleep testing, registering a 97 percent data recovery rate during that period.

Furthermore, patients reported an average comfort score of 2 (on a scale of 1 to 10, where 1 is the most comfortable). As a result, the authors have determined that Holter oximetry represents a new, easy to use, and reliable device for the home diagnosis of obstructive sleep apnea, useful in measuring outcomes for the surgical and non-surgical treatment of obstructive sleep apnea in adults and children.

Sleep apnea, which affects over 10 million Americans, with an estimated additional 10 million undiagnosed, is characterized by loud snoring interrupted by frequent episodes of totally obstructed breathing (obstructive sleep apnea). Serious episodes last more than ten seconds each and occur more than seven times per hour. Apnea patients may experience 30 to 300 such events per night. These episodes can reduce blood oxygen levels, causing the heart to pump harder.

Recently, the Centers for Medicare & Medicaid Services (CMS) changed their national coverage determination to include Type II, III, and IV devices for home sleep testing for sleep disorders including obstructive sleep apnea.

* Title: Reliability of Holter Oximetry for Home Sleep Apnea Testing. Presenters: Jordan C. Stern, MD (presenter); Conor Heneghan, PhD; Redmond Shouldice, BE, PhD. Date: September 23, 2008