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There’s more bad news for women with sleep apnea. A new study from the UCLA School of Nursing shows that the body’s autonomic responses — the controls that impact such functions as blood pressure, heart rate and sweating — are weaker in people with obstructive sleep apnea but are even more diminished in women.

Women with obstructive sleep apnea may appear to be healthy — having, for instance, normal resting blood pressure — and their symptoms also tend to be subtler, which often means their sleep problem is missed and they get diagnosed with other conditions.

“We now know that sleep apnea is a precursor to bigger health issues,” said Paul Macey, lead researcher on the study, which appears Oct. 23 in the peer-reviewed journal PLOS ONE. “And for women in particular, the results could be deadly.”

Obstructive sleep apnea is a serious disorder that occurs when a person’s breathing is repeatedly interrupted during sleep, sometimes hundreds of times. Each time, the oxygen level in the blood drops, eventually resulting in damage to many cells in the body. The condition affects more that 20 million adults in the U.S. and is associated with a number of serious health consequences and early death. Women are much less likely to be diagnosed than men.

For the study, men and women — both with and without obstructive sleep apnea — had their heart-rate responses measured during three physical tasks:

  • The Valsalva maneuver: Subjects breathe out hard while the mouth is closed.
  • A hand-grip challenge: Subjects squeeze hard with their hand.
  • A cold pressor challenge: A subject’s right foot is put in almost-freezing cold water for a minute.
In all three tests, changes to the normal heart rate were lower and delayed in patients with obstructive sleep apnea, compared with healthy controls. The researchers found that the difference was even more pronounced in women.

 

“The heart-rate results for these tests show that the impact of sleep apnea, while bad in men, is more severe in women,” Macey said. “This may mean that women are more likely to develop symptoms of heart disease, as well as other consequences of poor adaptation to daily physical tasks. Early detection and treatment may be needed to protect against damage to the brain and other organs.”
The next step in the research is to see if the autonomic responses improve with treatments such as continuous positive airway pressure (CPAP), the usual sleep apnea therapy, in which a machine is used to help an individual breathe easier during sleep. Researchers also intend to investigate the affect of other treatments.

The study was funded by the National Institutes of Health and the National Institute of Nursing Research. Other authors of the study included Rajesh Kumar, Mary Woo, Frisca Yan-Go and Ronald Harper, all of UCLA.

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Obstructive sleep apnea is known to be associated with an increased incidence of cardiovascular disease. Now a new study indicates that OSA is associated with subclinical myocardial injury, as indicated by increased high sensitivity troponin T (hs-TnT) levels. Elevated hs-TnT levels are predictive of both coronary heart disease (CHD) and heart failure (HF) in the general population. This is the first study to demonstrate an independent association between sleep apnea severity and this marker of early myocardial injury.

“Although OSA is associated with increased cardiovascular risk, a causal association has been hard to establish because of the association of OSA with other risk factors,” said researcher Amil M. Shah, MD, MPH, of the Brigham and Women’s Hospital in Boston. “In our study, we were able to demonstrate that greater OSA severity is independently associated with higher hs-TnT levels, suggesting a role for subclinical myocardial injury in the relationship between OSA and heart failure.”

The findings were published online ahead of print publication in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.

Source: Science Daily

The risk of death goes up with the severity of a person’s obstructive sleep apnea, according to a new study in Korea.

The Journal of Clinical Sleep Medicine study is the first to find that sleep apnea severity is linked with death risk in an Asian population, said researchers from Chosun University Hospital, Seoul National University College of Medicine and the Seoul National University Bundang Hospital. Previous studies had only looked at Western populations.

Researchers analyzed data from 2,240 people ages 40 and older with sleep apnea or snoring who visited the Sleep Center of Seoul National University Bundang Hospital at some point between 2003 and 2009. All the study participants underwent a full-night polysomnography testing, through which researchers were able to deduce the number of times they stopped breathing throughout the night due to their sleep apnea. They were then grouped into categories based on sleep apnea severity (no sleep apnea, moderate sleep apnea, moderate sleep apnea and severe sleep apnea).

All the participants who had at least mild sleep apnea (about 1,800 of the participants) were assigned to undergo surgery, CPAP, a mandibular advancement device, or a combination of the three.

The participants were followed up with until Dec. 31, 2011; the average participant was observed for 61.4 months, or a little more than five years. Of those with at least mild sleep apnea, 735 received treatment for the condition; the other 1,065 were not treated either because they refused treatment, they became lost during the follow-up period, they wanted to try losing weight, or they wanted to try sleeping in a different position.

Over the study period, 69 people (3.08 percent of the study group) died. Researchers found that the death rate was higher in the groups of people with more severe sleep apnea, compared with less severe or no sleep apnea. Specifically, 1.81 percent of people with no sleep apnea died over the study period, 2.18 percent of people with mild sleep apnea died, 3.54 percent of people with moderate sleep apnea died and 4.2 percent of people with severe sleep apnea died. Heart disease and strokes were the cause of about a third of the deaths.

Overall, the risk of dying was 2.47 times higher among people with severe sleep apnea compared with people without sleep apnea.

Source: Huffington Post

 

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The severity of sleep apnoea can independently predict the aggressiveness of malignant skin melanoma, according to a new study.

The research, presented at the European Respiratory Society (ERS) Annual Congress, adds new evidence to a number of studies that have found a link between cancer and the sleep disorder.

Previous studies have looked at a link between sleep apnoea and both mortality and incidence rates from cancer. Some experimental studies in mice have also shown that reduced oxygen levels in the blood, which is common in sleep apnoea, enhanced tumour growth. This is the first study in humans to look at the link between a specific type of cancer (skin melanoma) and sleep apnoea.

Researchers studied 56 patients diagnosed with malignant skin melanomas. They measured the aggressiveness of the cancer along with the presence and severity of sleep apnoea.

60.7% of the patients had sleep apnoea and 14.3% had severe sleep apnoea. The results found that the melanoma was more aggressive as the severity of sleep apnoea increased. This was the case for all three measurements for sleep apnoea severity. The severity measurements were also linked with other factors of aggressiveness, including the growth rate or the depth of invasion of the tumour.

Lead author, Dr Francisco Campos-Rodriguez, from the Hospital de Valme in Seville, Spain, said: “This is the first study in a human sample to show that sleep apnoea can worsen the outcomes of melanoma. The findings are from a preliminary small sample, but if the results are confirmed in larger studies, this would have important clinical implications, particularly as sleep apnoea can be easily treated and this could open up new therapeutic possibilities for people with both conditions. We have just begun a bigger prospective trial enrolling 450 patients with cutaneous melanoma to analyse this link further.”

 

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ResMed has announced at the ESC Congress 2013, that SERVE-HF has completed enrollment. SERVE-HF is an international, randomised study of 1,325 participants investigating if the treatment of central sleep-disordered breathing (central sleep apnea) improves survival and outcomes of patients with stable heart failure.

Approximately 14 million people in Europe are living with heart failure and central sleep-disordered breathing is known to be a highly prevalent co-morbidity in these patients. With an estimated 30-50 percent of heart failure patients potentially at risk from this condition, the results from SERVE-HF may have important consequences for the future management of these patients.

“Completing recruitment of SERVE-HF has been an important milestone in this landmark trial,” said co-principal investigator, Professor Martin Cowie of the Royal Brompton Hospital in London. “We owe much to the commitment and dedication of SERVE-HF investigators and to a strong collaboration between sleep specialists and cardiologists. We now look forward to results in 2016 and to a fuller understanding of just how important the treatment of central sleep-disordered breathing is in heart failure patients.”

SERVE-HF will, for the first time, provide conclusive evidence of the health impact of effectively treating heart failure patients who have central sleep-disordered breathing. The trial, which began in 2008, is sponsored by ResMed. Designed as an event-driven study, its completion is anticipated by mid-2015 and results are expected to be available in the first half of 2016.

 

 

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Medical Xpress reports that women diagnosed with gestational diabetes are nearly seven times more likely to have obstructive sleep apnoea than other pregnant women, according to a recent study accepted for publication in The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM). Gestational diabetes causes glucose levels in the bloodstream to rise above normal levels. This form of diabetes occurs during pregnancy, typically in the second trimester. Between four and eight of every 100 pregnant women in the United States develop gestational diabetes.

The new study found a link between gestational diabetes and sleep apnoea, which causes brief interruptions in breathing during sleep. If sleep apnea goes untreated, it can raise the risk for stroke, cardiovascular disease and heart attacks.

“It is common for pregnant women to experience sleep disruptions, but the risk of developing obstructive sleep apnea increases substantially in women who have gestational diabetes,” said Sirimon Reutrakul, MD, who conducted the research at Rush University Medical Center in Chicago. “Nearly 75 percent of the participants in our study who had gestational diabetes also suffered from obstructive sleep apnoea.”

In a series of observational case control studies, researchers monitored 45 women for sleep apnoea and other sleep disruptions. The research examined sleep health in 15 pregnant women who had gestational diabetes, 15 pregnant women who did not have the condition and 15 women who were not pregnant and did not have diabetes.

The study found a strong association between obstructive sleep apnoea and gestational diabetes in this group of mostly overweight or obese women. Pregnant women who did not have gestational diabetes were able to get an additional hour of sleep and had less fragmented sleep than women who had gestational diabetes. Past research has shown lost sleep, fragmented sleep and shorter periods spent in deep sleep – all symptoms of sleep apnoea – are likely to raise the risk a person will develop diabetes.

“Based on these findings, women who have gestational diabetes should be considered for evaluation for obstructive sleep apnoea, especially if other risk factors such as hypertension or obesity are present, and women already diagnosed with sleep apnoea should be monitored for signs of gestational diabetes during pregnancy,” Reutrakul said.

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New research published in the American Journal of Physiology – Regulatory Integrative and Comparative Physiology, suggests the estimated 12 million Americans who have obstructive sleep apnea should take better care to sleep in a very dark room. Scientists at The Ohio State University Wexner Medical Center have found exposure to dim light at night can interact with sleep apnea and lead to increased levels of depression and anxiety in mice.

“Although it is unclear at the present time whether sleep apnea causes depression, both conditions are commonly seen together in patients. Our research suggests that sleeping even with a minimum amount of light may increase symptoms of depression in those with sleep apnea,” said Dr. Ulysses Magalang, director of Ohio State’s Sleep Disorders Center and a co-author of the study.

The study involved mice that were placed in sleep apnea-like conditions that mimic the repetitive lowering of oxygen levels that sleep apnea patients experience. Half were kept in normal lighting conditions during the day and total darkness at night. The other half was exposed to dim light at night using a 40-watt light bulb in the lab. The group in dim light had higher anxiety behaviors and more depressive behaviors than the mice kept in the dark environment. Scientists also observed impaired learning and memory among both sets of mice.

“Not only were these changes observed during field and maze tests, but we also recorded physical changes, including a reduction of cell size in the hippocampus, an area of the brain important in memory and spatial navigation,” said Taryn Aubrecht, first author of the study and a neuroscience graduate student at Ohio State. “The combination of dim light exposure and sleep apnea appears to result in increased depressive and anxiety-like behaviors in mice, so limiting exposure to light at night could be a very simple strategy to help patients with sleep apnea,” Magalang said. “We’re currently exploring further human testing.”

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Science Nordic reports ona new which study reveals that children with obstructive sleep apnoea have a 6.5 times higher mortality rate than other children. Children who suffer obstructive sleep apnoea experience repetitive pauses in breathing during sleep. This interrupts their sleep, which can lead to irritability, poor concentration and slower growth. However, these children often have other and more serious ailments to deal with.

”This is the first systematic study of mortality after children have been diagnosed [with obstructive sleep apnoea], and we were surprised to see that it was this high,” says the lead author of the study, Professor Poul Jørgen Jennum, the head of research at the Clinical Neurophysiological Research Unit at Glostrup Hospital, Denmark.

“Our study also shows that children with sleep apnoea are more prone to illness – both before and after being diagnosed.”

Sleep apnoea can occur on its own, but it is frequently described as an ‘accompanying disease’, as it is often accompanied by other serious diseases. This is one of the reasons why it is so hard to figure out why these children lose their lives. We know that sleep apnoea in itself is dangerous, but often there are other diseases too, and that may be where the explanation for the high mortality rates can be found.

“We cannot say with certainty what it is that kills these children,” says Jennum. “We know that sleep apnoea in itself is dangerous, but often there are other diseases too, and that may be where the explanation for the high mortality rates can be found.”

Obesity has become an increasingly prevalent cause of sleep apnoea. In rare cases, sleep apnoea is caused by neurological or genetic disorders, he explains. Children with sleep apnoea often experience learning difficulties and an erratic appetite as a consequence of the constant interruption of their sleep.

Since they rarely or never reach REM sleep, they do not produce sufficient amounts of growth hormones. This is why they are usually shorter, on average, than other children. The long pauses in breathing also strain the heart and may in the worst case cause brain damage. If the underlying cause of the sleep apnoea can be removed, the children will grow taller.

“Our study suggests that many children with sleep apnoea are probably not being diagnosed and treated correctly,” says Jennum.

The study is published in the journal Thorax.

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An Australian study at Royal Melbourne Hospital has found a link between epilepsy and obstructive sleep apnoea (OSA). OSA is a type of ‘sleep-disordered breathing’. It is when a person has problems breathing while they are asleep, caused by obstruction (blockage) of the airway.

Previous research has suggested that people with epilepsy have a higher risk of sleep-disordered breathing than other people. Some people also experience weight-gain as a side-effect of epilepsy medication – which can also increase this risk.

Prof Terry O’Brian and his team recruited 87 people with epilepsy and monitored their sleep patterns. In the general population, between three and seven per cent of people experience sleep-disordered breathing. Of the 87 people with epilepsy studied, 22 per cent (almost a quarter) had trouble breathing that was severe enough to need treatment.

Fortunately, treating OSA is relatively simple. The people experiencing OSA were given a continuous positive airway pressure (CPAP) device to wear during sleep. The device maintains a steady pressure that prevents disordered breathing.

Prof O’Brian said in a press release: “It is important to diagnose [OSA] in patients with epilepsy, as treatment with CPAP can improve sleep quality and seizures, and associated problems like day time drowsiness, difficulty concentrating and cardiovascular disease, often without the requirement of medication.”

The full study findings were published in an online edition of Epilepsy Research on 27 March.

Source: Epilepsy Today

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WebMD reports on a new study published in the BMJ in which researchers took a close look at the effect of poor sleep on the chance of work-related injuries. They pooled the results of 27 studies, which included more than 268,000 working adults. Through interviews, questionnaires, and doctors’ diagnoses, the studies identified which people had sleep problems. The researchers then looked at whether workplace injuries were more likely among people with sleep difficulties than among those without these problems.

The researchers found a strong link between sleep problems and work injuries. People with sleep difficulties were around 60 percent more likely to have an injury at work than those without these problems. Overall, the researchers estimated that 13 in every 100 work injuries were related to poor sleep.

When the researchers looked at different types of sleep problems, they found that people who had sleep apnoea or took sleep medicines had the highest chance of work injuries. Perhaps surprisingly, the risk of injury related to poor sleep was lower for workers in industrial jobs and other physically demanding work (such as farming, mining, and building) than for workers overall.

This was a well-conducted review of studies, and it should provide a reliable summary of what the current research tells us about sleep problems and work injuries. However, it’s worth noting that the review didn’t include studies looking at poor sleep and driving-related work injuries. If these studies were included, the overall risk of work injuries related to poor sleep could be even higher.

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