Category: Obstructive Sleep Apnea

Stroke victims tend to do worse if they also have diagnosed or undiagnosed obstructive sleep apnea prior to having the stroke, according to a study presented April 28, 2009, at the American Academy of Neurology (AAN) annual meeting in Seattle.

Latha Stead, M.D., professor and chair of the Department of Emergency Medicine at the University of Rochester Medical Center, and professor of Neurosurgery, reported the findings at AAN, along with several other stroke studies measuring the factors that lead to a poor prognosis.

"We know that obstructive sleep apnea has been linked to a multitude of cardiovascular problems, yet it is concerning that the vast majority of cases remain undiagnosed," Stead said. "In the context of recovering from a stroke, sleep apnea can have a serious impact, and for that reason we encourage people to become more aware of obstructive sleep apnea and to get treatment."

The prospective study included 174 patients who were diagnosed with an acute ischemic stroke in the emergency department at the Mayo Clinic between June 2007 and March 2008. (Stead was the inaugural chair of the Division of Emergency Medicine Research at Mayo before recently joining the URMC.) The stroke-sleep study was conducted in collaboration with Virend Somers, M.D., Ph.D., who is well known for his work in sleep apnea.

Researchers used a standard questionnaire to assess the risk of sleep apnea among all 174 patients, sometimes aided by the patients' sleep partners. They found that 60 percent were at high risk of sleep apnea, seven patients had a previous diagnosis of sleep apnea, and those seven patients had a higher risk of death within the first month following the stroke.

After adjusting for age and stroke severity, researchers also found that high risk of obstructive sleep apnea was a predictor of having a worse outcome. Stroke patients with diagnosed or undiagnosed sleep apnea were also more disabled at the point of discharge from the hospital. Other studies have shown similar results, Stead said, but the latest research included a larger sample size compared to earlier studies.

Strokes are the third leading cause of death and the leading cause of disability in the United States. Since sleep apnea is a breathing disorder associated with the collapse of the pharyngeal airway, it causes potentially dangerous fluctuations in blood pressure.

Researchers do not know the exact mechanisms associated with sleep apnea and poorer outcomes following a stroke. But Stead noted it is more difficult for the brain and related tissue to heal when blood is not properly oxygenated during a disrupted sleep cycle. Furthermore, patients do not respond well to stroke rehabilitation programs when they are repeatedly sleep deprived.

"The next step," she said, "is to begin routine screening for obstructive sleep apnea as part of the emergency department evaluation of stroke patients."

Stead and research colleagues also presented a study at AAN showing that high blood sugar, or hyperglycemia, is another predictor of early death following a stroke. While other studies have shown that diabetics face poorer outcomes after a stroke, this study focused on non-diabetics or undiagnosed diabetics who had higher-than-normal blood sugar levels in the emergency department.

"The important message is that in the Emergency Department setting, it's critical to investigate all of the known risk factors that indicate a poor prognosis following a stroke," Stead said. Other known risk factors include low blood pressure and irregular heart rhythm.

Stead's research is funded by a Mayo Foundation Emergency Medicine Research Career Development Award.

A new study is the first to assess the effectiveness of treating sleep disorders in adults with a traumatic brain injury (TBI). Results indicate that treatment may result in the objective resolution of the sleep disorder without improvements in daytime sleepiness or neuropsychological function.

Results show that in brain-injured subjects with obstructive sleep apnea (OSA), three months of treatment with continuous positive airway pressure (CPAP) therapy dramatically reduced the severity of OSA from 31.4 to 3.8 apneas and hypopneas per hour of sleep; however, there was no demonstrable improvement in measures of daytime sleepiness. Participants experienced no significant changes in measures of mood, quality of life and cognitive performance after treatment for a sleep disorder.

According to principal investigator Richard J. Castriotta, M.D., director of the division of Pulmonary, Critical Care and Sleep Medicine at the University of Texas Health Science Center in Houston, researchers were not surprised by the fact that patients with sleep disorders had more severe injuries; however the lack of improvement in excessive sleepiness and neuropsychological testing after treatment was unexpected.

"The TBI patients with sleep apnea and no improvement in sleepiness may have had a combination of pre-existing sleep apnea and posttraumatic hypersomnia, causing sleepiness after the injury," said Castriotta. "These patients may need stimulant therapy in addition to CPAP in order to improve symptoms."

The study involved 57 adults with an average age of 39 years who had suffered a traumatic brain injury at least three months earlier (average 68 months). Seventy-seven percent of the injuries (44) were incurred as a result of a motor-vehicle accident; other causes were assault, a fall or a falling object. Sixty-one percent of the subjects (35) were free of a sleep disorder, while 23 percent (13) had OSA, 7 percent (4) had periodic limb movements in sleep (PLMS), 5 percent (3) had narcolepsy without cataplexy and 3 percent (2) had post-traumatic hypersomnia.

Participants underwent objective evaluation by overnight polysomnography to detect the presence of sleep disorders, and both objective and subjective tests were used to measure daytime sleepliness, mood, quality of life and cognitive performance. Subjects who were diagnosed with OSA received individualized treatment with CPAP therapy while those suffering from narcolepsy, post-traumatic hypersomnia and PLMS received predetermined dosages of medications that were not adjusted after assessment.

According to the authors, research has shown that some OSA patients have residual hypersomnia despite adequate CPAP therapy, which may explain the lack of improvement in measures of daytime sleepiness. Castriotta stated that the study illustrates how difficult it can be to measure the burden of sleep disorders in people with traumatic brain injuries.

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Journal Reference:

1. . Treatment of Sleep Disorders after Traumatic Brain Injury. Journal of Clinical Sleep Medicine, April 15, 2009

Sleep disordered breathing, also known as sleep apnea, is highly prevalent among retired National Football League (NFL) players, and particularly in linemen, according to Mayo Clinic research. This study, involving 167 players, adds to the growing body of research examining the relationship between sleep apnea and heart disease, the investigators say.

The study will be presented March 31, 2009 at the American College of Cardiology Annual Scientific Session in Orlando (1048-86). The research was conducted in collaboration with the Living Heart Foundation.

The Mayo data showed that 60 percent of linemen, average age of 54, had sleep disordered breathing (SDB), as defined by having at least 10 sleep-related breathing disorder episodes, such as pauses in breathing, per hour. Linemen had an average of 18.1 episodes per hour. The monitoring of breathing at night was conducted while the retired players slept at home. In addition, researchers discovered that age and obesity (measured by the body mass index, which corrects the weight for a person's height) were significantly associated with sleep disordered breathing. Linemen had an average BMI of 34.2; a BMI of 30 or more is considered obese.

Dr. Virend Somers, a Mayo Clinic cardiologist who helped guide the study, noted that the prevalence of sleep apnea and obesity was higher than expected, and serves as a warning that athletes need to monitor their weight and health carefully when they retire, a time when physical activity levels may begin to decline abruptly. While more research is needed to uncover the link between sleep disorders and heart disease, there is evidence that sleep apnea may be a cause of high blood pressure, which is a risk factor for heart disease, he says.

For all other study participants (average age of 53), who played other positions, 46 percent had sleep apnea with an average of 13.4 sleep-related disorder episodes per hour. The average BMI was 30.5.

In addition, 45 percent of the linemen and 32 percent of nonlinemen reported having high blood pressure. "High blood pressure is another risk factor for cardiac disease, and may be linked to both obesity and sleep apnea," Dr. Somers says.

Retired football players, and particularly linemen, need to be aware of sleep disordered breathing and its connection to cardiac risk factors, says lead author Felipe Albuquerque, M.D. "Many people do not realize that they have a sleep disorder," he says. "They may have no symptoms that they are aware of, but perhaps they know they are tired during the day and they're told they snore very loudly. These can be clues to the presence of sleep apnea. Our results show that retired linemen need to realize that they are a very high risk population and may need evaluation and treatment."

Previous research by various institutions and investigators in recent years, much of which has been assisted by the Living Heart Foundation, showed concerning health trends for retired NFL players:

Retired NFL players are more prone to obesity and obstructive sleep apnea than the general population.

Retired NFL players have an increased rate of metabolic syndrome, a condition increasingly linked to excess weight and lack of activity, which can lead to type 2 diabetes.

Higher mortality is reported in linemen, as compared to people in the general population of the same age who are not professional football players. Research is needed to determine the causes.

Breathing during sleep is often impaired in patients with atrial fibrillation. In the current edition of Deutsches Ärzteblatt International,* Thomas Bitter and his coauthors from the Ruhr University in Bochum investigate how often sleep-disordered breathing occurs in this form of cardiac arrythmia and what the different types are.

The authors used cardiorespiratory polygraphy to investigate whether 150 patients (110 men and 40 women) with atrial fibrillation suffered from sleep-disordered breathing. To avoid statistical bias, they only included patients with normal systolic left ventricular function. The mean age of the patients was around 65 years.

Breathing during sleep was impaired in 74% of the patients. 43% of the group suffered from obstructive sleep apnea (OSA). This means that the upper respiratory tract is constricted during the night, leading to oxygen deficiency. The authors found that 31% of patients suffered from central sleep apnea (CSA). This type of disorder is characterized by periodic decreases and increases in the respiratory depth and rate. Breathing becomes flatter and flatter, until it is interrupted for an interval.

Awareness of OSA already plays an important role in the primary and secondary prevention of atrial fibrillation. According to the authors, the results indicate that central sleep apnea is also relevant.

* Dtsch Arztebl Int 2009; 106(10): 164–70

Truck crashes are a significant public health hazard causing thousands of deaths and injuries each year, with driver fatigue and sleepiness being major causes. A new study has confirmed previous findings that obesity-driven testing strategies identify commercial truck drivers with a high likelihood of obstructive sleep apnea (OSA) and suggests that mandating OSA screenings could reduce the risk of truck crashes.

OSA is a syndrome characterized by sleep-disordered breathing, resulting in excessive daytime sleepiness, sleep attacks, psychomotor deficits, and disrupted nighttime sleep. It increases the risk of motor vehicle accidents, and is common among truck drivers. Approximately 2.4 to 3.9 million licensed commercial drivers in the U.S. are expected to have OSA. In addition to being unrecognized or unreported by drivers, OSA often remains undiagnosed by many primary care clinicians despite the fact that OSA increases the risks of hypertension, diabetes mellitus, and heart disease.

Philip Parks, MD, MPH, medical director of Lifespan's employee health and occupational services, is the study's lead author. He worked with researchers at the Cambridge Health Alliance on the study published in the March 2009 edition of the Journal of Occupational and Environmental Medicine. Parks says, "It is well-known that obesity, a leading risk factor for obstructive sleep apnea, is on the rise in the United States. Truck drivers with sleep apnea have up to a 7-fold increased risk of being involved in a motor vehicle crash."

Over the 15-month study period, 456 commercial drivers were examined from over 50 different employers. Seventy-eight (17%) met the screening criteria for suspect OSA. These drivers were older and more obese, and had a higher average blood pressure. Of the 53 drivers who were referred for sleep studies, 33 did not comply with the referral and were lost to follow-up. The remaining 20 were all confirmed to have OSA, but after diagnosis, only one of these 20 drivers with confirmed OSA complied with treatment recommendations.

Parks also notes, "Although it is not surprising, it is concerning that we found that drivers with sleep apnea frequently minimize or underreport symptoms such as snoring and daytime sleepiness. In our study, the majority of truck drivers did not follow through on physician recommendations for sleep studies and sleep apnea treatment." He continues, "As a result, it is possible that many of the 14 million truck drivers on American road have undiagnosed or untreated sleep apnea."

Stefanos N. Kales, MD, MPH, Medical Director of Employee and Industrial Medicine at Cambridge Health Alliance, is the study's senior author. Kales says, "It is very likely that most of the drivers who did not comply with sleep studies or sleep apnea treatment sought medical certification from examiners who do not screen for sleep apnea and are driving with untreated or inadequately treated sleep apnea."

The study, published today by the Journal of Occupational and Environmental Medicine, has significant policy ramifications, as the Federal Motor Carrier Safety Administration is currently deliberating recommendations to require sleep apnea screening for all obese drivers based on body mass index or "BMI" (BMI is calculated based on height and weight). The Administration requires medical certification of licensed commercial drivers at least every two years. These occupational medicine exams present a unique opportunity for detecting OSA as part of determining a driver's safety behind the wheel.

"OSA screenings of truck drivers will be ineffective unless they are federally mandated or required by employers," said Kales. The study's authors also support the prohibition of "doctor shopping." Dr. Kales added, "Such action would prohibit drivers diagnosed with a serious disorder that might limit driving or require treatment to seek out more lenient or less rigorous medical examiners."

This study was supported by the Federal Motor Carrier Safety Administration, a research award from the American College of Occupational and Environmental Medicine, and the National Institute for Occupational Safety and Health Education and Research Center.

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Journal Reference:

1. Philip D. Parks, MD, MPH, MOccH; Gerardo Durand, MD; Antonios J. Tsismenakis, MA; Antonio Vela-Bueno, MD; Stefanos N. Kales, MD, MPH. Screening for Obstructive Sleep Apnea During Commercial Driver Medical Examinations. Journal of Occupational and Environmental Medicine, March 2009, Vol. 51, Issue 3

Diagnosing and treating obstructive sleep apnea may soon become much less expensive and arduous, thanks to new research showing that a simplified program using experienced nurses, home ambulatory diagnosis and auto-titrating continuous positive airway pressure (CPAP) machines to titrate CPAP pressures is not inferior to the traditional model which relies on specialist physicians and sleep studies.

The randomized, multi-center study directly compared the results of two OSA diagnosis and treatment protocols, "simplified" and traditional, as well as there respective costs.

The results were published in the second issue for March of the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.

"The main finding of the study was that the simplified model of care was not inferior to the usual physician-led, hospital-based model," said Nick A. Antic, Ph.D., at the Adelaide Institute for Sleep Health in South Australia.

Obstructive sleep apnea, which may affect as many as 20 to 30 million adult Americans and a growing number of people worldwide, is independently linked to cardiovascular problems, hypertension and other co-morbidities, as well as an increased risk of motor vehicle accidents. As obesity continues to be a growing problem in Western and developing countries, the prevalence of OSA is almost certainly rising with it.

The serious complications of OSA, together with its increasing prevalence, make its diagnosis a pressing public health issue. However, traditional diagnosis and treatment of OSA can be expensive and time-consuming. Diagnosis and treatment are also limited by the availability and accessibility of the sleep centers and specialist doctors required. "In Western countries, the waiting lists for sleep medicine service are often very long. In developing countries, there may be no sleep medicine services at all in many areas," said Dr. Antic.

To determine whether diagnosis and subsequent treatment could be simplified without health costs to the patient, Dr. Antic and colleagues developed a nurse-led diagnosis and treatment model that featured ambulatory overnight oximetry and auto-titrating CPAP machines to set fixed CPAP under nurse supervision. They compared the results of patients thus diagnosed and treated to those who underwent standard sleep medicine pathways, including laboratory-based polysomnography, CPAP titration and physician management of the patient.

They assessed the patients' sleepiness on the validated Epworth Sleepiness Scale (ESS) and set the minimal clinically significant change at +/- 2 points. They also assessed other outcomes of sleep, including quality of life measures, executive neurocognitive function on maze tasks and maintenance of wakefulness tests and CPAP adherence. In all, the study assessed almost 200 patients with moderate to severe OSA who were randomly assigned to the simplified or traditional model.

The patients in the nurse-led group spent about 50 minutes longer with the nurse than the patients in the physician-led groups, but were seen by physicians 12 percent of the time. Patients in the physician-led group, meanwhile, had an average of 2.36 consultations with physicians, as opposed to 0.18 for patients in the nurse-led group.

Despite these obvious differences, none of the secondary outcomes measured showed significant differences between the groups, and differences in ESS scores between groups were lower than the pre-determined minimum for clinical significance.

Notably, the patients in the nurse-led group were diagnosed and treated for $722 U.S. dollars less per patient than those in the physician-led group, but did not suffer from inferior care or outcomes.

"While we were not surprised at this finding, we were very pleased, as it indicates a robust new avenue for providing better access to sleep services for those with moderate-severe OSA in a timely yet cost effective fashion without sacrificing patient outcomes," said Dr. Antic.

Edward Grandi, Executive Director of the American Sleep Apnea Association welcomes the results of the study saying, "This approach could benefit a significant number of the less complicated apnea cases that are currently untreated due to cost constraints."

"The next step is to test these models in primary care settings," said Dr. Antic. "This project is underway and preliminary data will be presented at the American Thoracic Society's International Conference in May."

A study in the Feb. 15 issue of the Journal of Clinical Sleep Medicine shows that a 40 minute protocol for the Maintenance of Wakefulness Test (MWT40) is superior to a 20-minute protocol (MWT20) at detecting excessive daytime sleepiness (EDS) in adults who may be unable to maintain wakefulness while driving. Yet results also suggest that the test may not be completely reliable when the strong motivation to keep a driver's license enables individuals to overcome sleepiness during the test.

Forty-one out of the 164 subjects in the study (25 percent) fell asleep in one or more of the MWT40 trials; 10 participants (6.1 percent) fell asleep in all four trials. Out of 39 subjects with severe obstructive sleep apnea (OSA), 19 (48.7 percent) fell asleep in at least one of the trials. In a previous study of the MTW20 protocol, only five out of 54 subjects (9.2 percent) fell asleep in any of the trials.

According to the principal investigator Giora Pillar, M.D, Ph.D, with the Sleep Laboratory at Rambam Medical Center in Haifa, Israel, it is very difficult to objectively assess and quantify the capability of an individual to remain vigilant. Many of the study's participants may have been highly motivated to overcome their sleepiness during the test in order to prevent their license from being revoked.

"It could be expected that the MWT40 will be superior to MWT20, but it is somewhat surprising that despite a strong drive to sleep, as in cases of severe apnea, people could pass the test by remaining awake in all trials," said Pillar. "It emphasizes the strong effect of motivation."

The study included 164 consecutive subjects with an average age of 50, who were referred to the Technion Sleep Lab between June 2006 and January 2007 by the Medical Institute for Driving Safety of the Ministry of Transportation. Participants who were suspected of suffering from EDS were referred for evaluation for their ability to maintain wakefulness for the purpose of renewal of their license to drive. Seventeen of the participants were professional drivers and one participant was an aviation pilot.

All subjects underwent a full-night polysomnograph followed by an MWT40, (four 40 minute long trials). During the MWT, participants were told to sit on a bed in a reclining position in a private, dimly lit room. Subjects were not allowed to perform any unusual action to maintain wakefulness, such as reading, talking, consuming caffeine or making repetitive movements. Trials were stopped if the subject fell asleep or if 40 minutes had passed.

According to Pillar, none of the participants who were receiving continuous positive airway pressure (CPAP) treatment failed the MWT 40; this information emphasizes the importance of treating OSA in preventing auto accidents caused by EDS. Pillar noted that findings of this study indicate that further research is necessary in order to determine a more efficient way to objectively assess an individual's ability to remain vigilant while driving.

According to the American Academy of Sleep Medicine (AASM), 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.

AASM practice parameters for the MWT recommend the 40-minute protocol and advise that the MWT be used when sleep clinicians require objective data to assess an individual's ability to remain awake. The MWT should be used in association with the clinical history to assess the ability to maintain wakefulness.

Heavy snoring can be far from a nuisance. It can be a sign of obstructive sleep apnea, a condition where an individual briefly stops breathing during the night which raises the risk of heart failure and strokes.

“Sleep apnea or sleep disordered breathing is one that we’re getting more and more interested in because we see a very strong association with strokes, heart attacks and other cardiovascular problems,” says Melvyn Rubenfire, M.D., director of Preventative Cardiology at the University of Michigan Health System’s Cardiovascular Center.

The cardiovascular risk factors that most often come to mind are smoking, diabetes, high blood pressure, high cholesterol and family history. But it’s important to be aware of the possible health risks of heavy snoring.

Snoring is caused by a blockage in the back of the throat. What you hear is the tongue forced to the back of the throat when a person is lying on their back.

When people snore they don’t always stop breathing, but there are chemicals in the brain that should trigger breathing that are not stimulated when a person snores. Without the stimulation the person will often stop breathing.

When a person obstructs at night and stops breathing, oxygen levels drop dramatically and hormones and adrenaline surge. Those hormones contribute to high blood pressure, irregularities of the heart and can trigger heart attacks

People who snore do not necessarily have obstructive sleep apnea but the relationship is pretty strong.

And the relationship between snoring and cardiovascular problems goes both ways. Those with heart problems are more likely to have sleeping disorders. For example, heart failure can lead to water retention – water buildup in legs, lungs and tissues in the back of the throat.

“So heart failure can be one of the causes of obstructive sleep apnea and obstructive sleep apnea can seriously worsen heart function and aggravate heart failure,” Rubenfire said.

Studies had long suggested a connection between snoring and cardiovascular problems but men made up most of the study group. According to a large study published in the February 2000 issue of the Journal of the American College of Cardiology, women who snore regularly have about twice the risk of heart attacks and strokes than women who never snore.

“Still it may be too early to tell if snoring is an independent risk factor for heart disease,” says Rubenfire who continues to review research on sleep disordered breathing as it relates to cardiovascular disease. “What we do know is if you treat people with obstructive sleep apnea the risk of cardiovascular disease improves dramatically.”

Rubenfire explains that anyone who snores loudly, wakes without feeling rested or has hypertension, diabetes or is overweight is more prone to sleep disordered breathing or obstructive sleep apnea.

The most important step in treating snoring is recognition and appropriate diagnosis. A very effective treatment – one that helps 90 percent of those who are compliant with the method – is using a Continuous Positive Airway Pressure device.

“These are excellent devices, called CPAP, … these are masks that prevent you from obstructing by creating some pressure,” says Rubenfire. “Simple snoring that’s not very loud and without any other symptoms can usually be handled simply by turning on your side.”

A device tested by The University of Texas Health Science Center at San Antonio Dental School helps pull the lower jaw forward, creating an open airway in the throat to benefit those with moderate to severe sleep apnea. It is more appealing, affordable and easier to use than standard therapies.

Imagine choking and gasping for air every time you fall asleep. Between 18 million and 20 million people in the United States suffer from these frightening symptoms because of a common disorder called sleep apnea. Because of a lack of awareness among both health professionals and the public, up to 90 percent of sufferers aren’t diagnosed or treated, and that could prove deadly.

When left untreated, sleep apnea may lead to more serious health problems. According to national health statistics, nearly 38,000 cardiovascular deaths annually are in some way related to sleep apnea.

Dental researchers offer new treatment alternative

Although treatment is available, many don’t comply with standard therapies. Researchers in the Dental School at The University of Texas Health Science Center at San Antonio are offering another treatment option that is more appealing, more affordable and easier to use than standard therapies.

The Thornton Adjustable Positioner is a device that helps pull the lower jaw forward, creating an open airway in the throat.

Paul McLornan, B.D.S., assistant professor in the Department of Prosthodontics, is the lead investigator of an 18-month study involving sleep apnea patients at the South Texas Veterans Health Care System, Audie Murphy Division. Researchers used an oral appliance called the Thornton Adjustable Positioner (TAP) to treat those suffering from moderate to severe sleep apnea.

Patients did not use standard treatment

“What we found was that many of our patients with moderate to severe sleep apnea were not adhering to standard treatment with a Continuous Positive Airway Pressure (CPAP) machine,” Dr. McLornan said. Although the CPAP is considered to be the gold standard in treating sleep apnea and is very effective, Dr. McLornan said compliance by patients is well below 50 percent.

“Some patients say the machine (which uses a face mask connected to tubes and blows air down a patient’s throat during sleep to keep the airway open), is cumbersome or noisy,” Dr. McLornan said. “Some said it was uncomfortable or that it bothered their spouses, or that they were just too embarrassed to use the machine.”

Dr. McLornan’s study proved that the TAP device, which is much smaller and fits in a patient’s mouth, is now an option for patients with severe sleep apnea.

New device moves lower jaw forward, opening the airway

Patients were fitted with the TAP appliance and given a tiny key that fits in the front of the device. The patient was instructed to wear the appliance every night and to insert and turn the key several millimeters before bedtime. By turning the key, the patient pulls his lower jaw forward, thus creating an open airway in the throat.

Patients in his study improved significantly when using the TAP. “We saw patients who began the study with severe sleep apnea end the study with very mild or no sleep apnea. They reported sleeping better, feeling more rested in the morning and altogether healthier.”

Dr. McLornan said this research is vital to both the medical and dental communities.

Many health issues associated with sleep apnea

“Sleep apnea is a growing and serious problem for people of all ages and all ethnic groups,” Dr. McLornan said. “If left untreated, it becomes progressively worse. People suffering from sleep apnea are at increased risk for high blood pressure, heart attacks, strokes, obesity and diabetes. It takes both dentists and medical professionals working together to control this potentially deadly disorder. The TAP gives patients another viable treatment alternative.” It is also less invasive and costly than CPAP or surgery.

Consult doctor with concerns about sleep apnea

Dr. McLornan said patients who think they may suffer from sleep apnea should consult their family physician and undergo a standard sleep study in a lab. Costs are normally covered by medical insurance.

The American Academy of Sleep Medicine, the professional society that sets the standards for and promotes excellence in sleep medicine, now recommends that oral appliances can be the first line of treatment for people with mild to moderate sleep apnea. Dr. McLornan’s study demonstrates it can be used for patients with severe problems as well.

 A new study in the journal Sleep shows that sleep duration is associated with changes in the levels of specific cytokines that are important in regulating inflammation. The results suggest that inflammation may be the pathway linking extreme sleep durations to an increased risk for disease.

Each additional hour of self-reported sleep duration was associated with an eight-percent increase in C-reactive protein (CRP) levels and a seven-percent increase in interleukin-6 (IL-6), which are two inflammatory mediators. In contrast, each hour of reduction in sleep measured objectively by polysomnography was associated with an eight-percent increase in tumor necrosis factor alpha, another pro-inflammatory cytokine.

"The most surprising finding was that we found different relationships based on how sleep was measured," said lead author Dr. Sanjay R. Patel, assistant professor of medicine at Case Western Reserve University in Cleveland, Ohio.

According to the authors, research has linked both short and long sleep durations with an increased risk for mortality, coronary heart disease, diabetes and obesity. Chronic elevations in cytokines such as CRP and IL-6 also are associated with an increased risk of problems such as diabetes and heart disease.

The study involved 614 individuals from the Cleveland Family Study, a longitudinal family-based epidemiological cohort designed to study the genetics of obstructive sleep apnea (OSA). Participants completed questionnaires about sleep habits and underwent one night of polysomnography. In the morning a fasting blood sample was collected, and it was analyzed for five inflammatory cytokines.

Mean self-reported habitual sleep duration was 7.6 hours; mean sleep duration measured by polysomnography on the night prior to blood sampling was 6.2 hours. Those with long sleep durations, assessed by either measure, were significantly younger. Short sleep duration measured by polysomnography was associated with an increased prevalence of diabetes, hypertension and obstructive sleep apnea.

According to the authors the differing patterns of association with cytokine levels suggest that self-reported habitual sleep duration may measure chronic sleep exposure, while polysomnography may measure an acute exposure. They also note that the two methods of measuring sleep duration may be influenced differently by an underlying predictor of sleep habits such as stress or mood, which may have a direct effect on cytokine levels.

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Journal Reference:

1. . Sleep Duration and Biomarkers of Inflammation. Sleep, Feb 1, 2009