Obstructive sleep apnea (OSA) is currently treated with mechanical devices - air pressure from CPAP, jaw movement with oral appliance therapy, or surgical therapy. No medications have been shown to be particularly helpful in treating OSA. This article discusses NIH funding given to a team of researchers at the University of Chicago.
The article describes the research already going on at the University that focuses on a small group of cells in the carotid artery called the carotid bodies. When levels of oxygen in the blood drop, these carotid bodies send signals to the brainstem to increase breathing, with the goal of increasing oxygen levels in the blood. The article describes that in sleep apnea, the carotid bodies may not react appropriately, and thus stop sending signals to the brain. The University of Chicago team has developed a compound that may help the carotid bodies to keep working properly during sleep apnea, and thus aid in their regulation of breathing - at least in rodents.
However, it's not clear what type of sleep apnea the researchers are working on. It sounds like central sleep apnea (CSA), which is a completely different, and less common form of sleep apnea, than OSA. In most cases of OSA, the drive to breathe is intact, but airflow is significantly reduced due to a blockage in the upper airway. In addition, not every patient with OSA has oxygen level reductions, even though airflow through the upper airway is reduced. But if a person with OSA has regular blood oxygen level reductions, perhaps a medication that helps the carotid bodies stimulate breathing may be effective, if that stimulation involves increasing the diameter of the upper airway.
Showing posts with label central sleep apnea. Show all posts
Showing posts with label central sleep apnea. Show all posts
Wednesday, February 4, 2015
Thursday, April 7, 2011
Treatment of Cheyne-Stokes Respiration
There is an article in Therapeutic Advances in Respiratory Disease that reviews Cheyne-Stokes respiration and its treatment. Viewer warning, this is a technically complicated subject.
There are two main types of sleep apnea. The most common is obstructive (OSA) characterized by repetitive closure of the throat while asleep. The other is central sleep apnea CSA), where the upper airway is open, but the brain does not tell the lungs to breathe often or deep enough. One type of CSA is Cheyne-Stokes respiration (CSR) characterized by brief, repetitive periods of waxing and waning breath depths and brief, repetitive complete pauses in breathing. It is most common in neurological and heart disease.
The exact reasons of why or how patients develop CSR is unknown. Breathing during sleep is controlled by carbon dioxide levels (and oxygen to some degree). In CSR, it is theorized that the brain is over- and under-reacting to changes in CO2 in such a way that the patient breathes too deep sometimes and not at all at other times.
Treatment of CSR is more challenging than OSA. Maximizing medical treatment of the underlyinig heart or brain disease is the first step. Supplemental oxygen used during sleep can help some CSR patients. Certain medications can help because, in theory, they are respiratory stimulants, but objective data do not overwhelmingly support their use.
CPAP has been shown to be effective in some, but not all CSR patients. There was a large trial in Canada that showed that CPAP can improve cardiac function, respiratory disturbances, sympatheticoadrenal activity, and exercise performance, but NOT survival times. However, a re-analysis of the Canadian trial showed a survival benefit in those patients whose breathing disturbances were sufficiently reduced as compared to those without improvement in respiratory disturbances. Therefore, optimal suppression of respiratory disturbances is essential in CSR patients.
Bilevel positive airway pressure (BiPAP) is occasionally used in CSR patients, but there is very limited data on this mode of therapy. Adaptive servo-ventilation (ASV) is a new type of airway pressure that adapts to the patient's waxing and waning breathing patterns. It has been shown to be effective in CSR patients and studies have shown it superior to CPAP and BiPAP.
There are two main types of sleep apnea. The most common is obstructive (OSA) characterized by repetitive closure of the throat while asleep. The other is central sleep apnea CSA), where the upper airway is open, but the brain does not tell the lungs to breathe often or deep enough. One type of CSA is Cheyne-Stokes respiration (CSR) characterized by brief, repetitive periods of waxing and waning breath depths and brief, repetitive complete pauses in breathing. It is most common in neurological and heart disease.
The exact reasons of why or how patients develop CSR is unknown. Breathing during sleep is controlled by carbon dioxide levels (and oxygen to some degree). In CSR, it is theorized that the brain is over- and under-reacting to changes in CO2 in such a way that the patient breathes too deep sometimes and not at all at other times.
Treatment of CSR is more challenging than OSA. Maximizing medical treatment of the underlyinig heart or brain disease is the first step. Supplemental oxygen used during sleep can help some CSR patients. Certain medications can help because, in theory, they are respiratory stimulants, but objective data do not overwhelmingly support their use.
CPAP has been shown to be effective in some, but not all CSR patients. There was a large trial in Canada that showed that CPAP can improve cardiac function, respiratory disturbances, sympatheticoadrenal activity, and exercise performance, but NOT survival times. However, a re-analysis of the Canadian trial showed a survival benefit in those patients whose breathing disturbances were sufficiently reduced as compared to those without improvement in respiratory disturbances. Therefore, optimal suppression of respiratory disturbances is essential in CSR patients.
Bilevel positive airway pressure (BiPAP) is occasionally used in CSR patients, but there is very limited data on this mode of therapy. Adaptive servo-ventilation (ASV) is a new type of airway pressure that adapts to the patient's waxing and waning breathing patterns. It has been shown to be effective in CSR patients and studies have shown it superior to CPAP and BiPAP.
Thursday, August 5, 2010
Sleep Duration and Cardiovascular Disease
The August edition of the journal Sleep has an article about the association of sleep duration and cardiovascular disease. It was based on a survey of over 30,000 Americans. The results showed that cardiovascular disease was more common in people who reported that they slept less than or greater than seven hours per night. These results were independent of age, sex, race, ethnicity, smoking, alcohol use, body mass index, physical activity, diabetes, high blood pressure, and depression.
The authors of the study did not determine the reason why sleep duration could affect cardiovascular disease, but they provided some theories. Hormonal and metabolic changes can occur in people who sleep less than seven hours, and these changes could impact cardiovascular health. People who sleep longer than seven hours could be sleeping that long due to an underlying sleep disorder, such as obstructive sleep apnea (OSA). OSA can impact cardiovascular health in a negative way.
Getting seven hours of sleep each night may not prevent you from having a heart attack, but getting the right amount of sleep can be an important part of overall good health.
The authors of the study did not determine the reason why sleep duration could affect cardiovascular disease, but they provided some theories. Hormonal and metabolic changes can occur in people who sleep less than seven hours, and these changes could impact cardiovascular health. People who sleep longer than seven hours could be sleeping that long due to an underlying sleep disorder, such as obstructive sleep apnea (OSA). OSA can impact cardiovascular health in a negative way.
Getting seven hours of sleep each night may not prevent you from having a heart attack, but getting the right amount of sleep can be an important part of overall good health.
Wednesday, July 7, 2010
The Other Sleep Apnea?
When patients ask me about sleep apnea, most often they are referring to obstructive sleep apnea, characterized by repetitive throat collapse while asleep. There is another type of sleep apnea, central sleep apnea, where a person will stop breathing, but the throat remains open.
Central sleep apnea occurs when a person breathes too slowly or not deep enough. It can occur in the setting of brain, heart, or lung diseases. In heart failure, central sleep apnea can be a problem, and not all cardiologists are aware of it.
The symptoms of central sleep apnea can be similar to those seen in obstructive sleep apnea, such as restless sleep, daytime sleepiness or extreme fatigue, and unusual breathing patterns while asleep (usually observed by a bed partner).
Although central sleep apnea gets less attention than the more common obstructive sleep apnea, both deserve to be treated since both conditions can increase mortality rates. However, the treatment for each sleep apnea type can be different, making it important to figure out the exact type of sleep apnea that is affecting the patient.
Central sleep apnea occurs when a person breathes too slowly or not deep enough. It can occur in the setting of brain, heart, or lung diseases. In heart failure, central sleep apnea can be a problem, and not all cardiologists are aware of it.
The symptoms of central sleep apnea can be similar to those seen in obstructive sleep apnea, such as restless sleep, daytime sleepiness or extreme fatigue, and unusual breathing patterns while asleep (usually observed by a bed partner).
Although central sleep apnea gets less attention than the more common obstructive sleep apnea, both deserve to be treated since both conditions can increase mortality rates. However, the treatment for each sleep apnea type can be different, making it important to figure out the exact type of sleep apnea that is affecting the patient.
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