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People with sleep apnea, a common sleep disorder, may be at increased risk for the bone-thinning disease osteoporosis, especially women and older people, a new study suggests.

Sleep apnea causes repeated, brief interruptions in breathing during sleep. Untreated sleep apnea can increase a person’s risk of heart disease, heart attack and stroke.

“Ongoing sleep disruptions caused by obstructive sleep apnea can harm many of the body’s systems, including the skeletal system,” said study co-author Dr. Kai-Jen Tien, of Chi Mei Medical Center in Tainan, Taiwan.

“When sleep apnea periodically deprives the body of oxygen, it can weaken bones and raise the risk of osteoporosis,” Tien said. “The progressive condition can lead to bone fractures, increased medical costs, reduced quality of life and even death.”

For the study, published April 15 in the Journal of Clinical Endocrinology & Metabolism, researchers analyzed the medical records of nearly 1,400 people in Taiwan diagnosed with obstructive sleep apnea between 2000 and 2008. They compared them with more than 20,600 people who did not have the sleep disorder.

Over six years of follow-up, people with sleep apnea were 2.7 times more likely to be diagnosed with osteoporosis. The risk for the bone-thinning disease was highest among women and older people with sleep apnea, according to the study.

“As more and more people are diagnosed with obstructive sleep apnea worldwide, both patients and health care providers need to be aware of the heightened risk of developing other conditions,” Tien said in a journal news release. “We need to pay more attention to the relationship between sleep apnea and bone health so we can identify strategies to prevent osteoporosis.”

However, the study only noted an association between sleep apnea and osteoporosis. It does not prove that one causes the other.

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Sleep apnea is common in people with multiple sclerosis and may contribute to their fatigue, a new study shows. Fatigue is one of the most frequent and debilitating symptoms experienced by MS patients. The study included 195 people with MS who completed a sleep questionnaire and were assessed for daytime sleepiness, insomnia, fatigue severity and sleep apnea.

One-fifth of the patients had been diagnosed with sleep apnea and more than half were found to have an elevated risk for the condition. The researchers also found that sleep apnea risk was a significant predictor of fatigue severity.

MS is a chronic, frequently disabling disease that attacks the central nervous system, according to the National Multiple Sclerosis Society. Symptoms range widely, from mild signs such as numbness in the limbs to severe symptoms including paralysis or loss of vision.

The new findings suggest that sleep apnea may be a common but under-recognized contributor to fatigue in MS patients, and doctors should not hesitate to check these patients for sleep problems, study author Dr. Tiffany Braley, an assistant professor of neurology at the University of Michigan Multiple Sclerosis and Sleep Disorders Centers, said in an AASM news release.

“Obstructive sleep apnea is a chronic illness that can have a destructive impact on your health and quality of life,” and MS patients at high risk for sleep apnea should undergo a comprehensive sleep evaluation, academy president Dr. M. Safwan Badr said in the news release.

The study appears in the Feb. 15 issue of the Journal of Clinical Sleep Medicine, an AASM publication. About 400,000 people in the United States have MS, according to the National Multiple Sclerosis Society. Up to 7 percent of men and 5 percent of women have sleep apnea, according to the AASM.

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A link has already been found between sleep apnea and hypertension but recent research suggests that if people have sleep apnea and hypertension, they should treat sleep apnea first and it will take care of hypertension.

The study involved 194 patients who were diagnosed with hypertension and also suffering from sleep apnea. Some patients were randomly administered CPAP while others were not. The patients continued to take their blood pressure medications.

It was found that those patients who received CPAP showed reduction in their blood pressure. Their average blood pressure of 24 hours was lowered 3.1 mm/Hg more than those who didn’t receive CPAP. Diastolic blood pressure also gets reduced by 3.2 mm/Hg. The study lasted for 12 weeks. At the end of the study, researchers noted that 36% of CPAP receiving patients showed 90% decline in their night time blood pressure as compared to 22% of those who didn’t receive CPAP.

Researchers found that prevalence of sleep apnea in patients who are suffering from hypertension is very high and undergoing from a standard sleep apnea treatment is beneficial for the patient. The further advised that individuals having sleep apnea should undergo sleep study to determine whether they are suffering from constructive sleep apnea.
Further studies are needed to evaluate long term benefits of this treatment.

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It’s well-established that obstructive sleep apnea is linked with increased heart risks. But now, a new study teases apart what exactly it is about the sleep disorder, characterized by pauses in breathing during sleep leading to disrupted sleep, that seems to predict these cardiovascular events.

Obstructive sleep apnea is measured by the number of times a person stops breathing during sleep (the apnea-hypopnea index, or AHI). However, researchers found that there were a number of other elements of sleep apnea that seemed to be predictive of cardiovascular events. The biggest one: the amount of time spent sleeping when the oxygen saturation was below 90 percent.

Other elements associated with a cardiovascular event included heart rate, daytime sleepiness, number of awakenings during the night, sleep time and leg movements, the researchers found. While the apnea-hypopnea index was associated with cardiovascular events when it was looked at by itself, it was no longer considered a significant predictor once all the other elements were factored in.

The study, published in the journal PLOS Medicine, is based on 10,149 people with obstructive sleep apnea who underwent diagnostic polysomnography between 1994 and 2010; 1,172 of those people developed cardiovascular disease.

“We believe a revision of the operative definition of OSA [obstructive sleep apnea] may be necessary, to reflect not simply the frequency of apneas and hypopneas, but the actual physiologic consequences that result — the severity of oxygen desaturation, sleep fragmentation, sleep deprivation and sympathetic activation,” the University of Toronto and St. Michael’s Hospital researchers said in the study. “It is these ‘downstream’ phenomena that we have found to be more predictive of CV [cardiovascular] risk.”

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A new study suggests that patients with spinal cord injuries could benefit from careful assessment for sleep apnoea.

Results show that 77 percent of spinal cord injury survivors had symptomatic sleep-disordered breathing, and 92 percent had poor sleep quality. The study also found that the nature of sleep-disordered breathing in patients with spinal cord injury is complex, with a high occurrence of both obstructive and central sleep apnea events. The occurrence of central sleep apnea, which requires special consideration in diagnosis and treatment, was more common in patients with a cervical injury than in those with a thoracic injury.

“The majority of spinal cord injury survivors have symptomatic sleep-disordered breathing and poor sleep that may be missed if not carefully assessed,” said principal investigator and lead author Dr. Abdulghani Sankari, physician scientist at John D. Dingell VA Medical Center and Wayne State University School of Medicine in Detroit, Mich. “Our findings help in identifying the mechanism of sleep-disordered breathing in spinal cord injury and may provide potential targets for new treatment.”

The study results appear in the Jan. 15 issue of the Journal of Clinical Sleep Medicine, which is published by the American Academy of Sleep Medicine.

“Sleep-disordered breathing may contribute to increased cardiovascular mortality in spinal cord injury patients,” said American Academy of Sleep Medicine President Dr. M. Safwan Badr, who was involved in the study. “All spinal cord injury patients should undergo a comprehensive sleep evaluation using full, overnight polysomnography for the accurate diagnosis of sleep apnea.”

Sankari and his team studied 26 chronic spinal cord injury patients, including 15 with cervical and 11 with thoracic injuries. All subjects had baseline spirometry, a battery of questionnaires and attended polysomnography with flow and pharyngeal pressure measurements.

According to the authors, this is the first study to assess sleep-disordered breathing and ventilation changes comparing two different levels of spinal cord injury — cervical vs. thoracic

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People with sleep apnoea and hard-to-control high blood pressure may see their blood pressure drop if they treat the sleep disorder, Spanish researchers report.

Patients in this study were taking three or more drugs to lower their blood pressure, in addition to having sleep apnoea. Participants who used the CPAP device for 12 weeks reduced their diastolic blood pressure (the bottom number in a blood pressure reading) and improved their overall night-time blood pressure, the researchers found.

“The prevalence of sleep apnoea in patients with resistant [high blood pressure] is very high,” said lead researcher Dr Miguel-Angel Martinez-Garcia, from the Polytechnic University Hospital in Valencia. “This [sleep apnoea] treatment increases the probability of recovering the normal nocturnal blood pressure pattern,” he said.

Patients with resistant high blood pressure should undergo a sleep study to rule out obstructive sleep apnoea, Martinez-Garcia said. “If the patient has sleep apnoea, he should be treated with CPAP and undergo blood pressure monitoring.”

The report, published in the issue of the Journal of the American Medical Association, was partly funded by Philips-Respironics, maker of the CPAP system used in the study. The CPAP system consists of a motor that pushes air through a tube connected to a mask that fits over the patient’s mouth and nose. The device keeps the airway from closing, and thus allows continuous sleep.

Dr Gregg Fonarow, a spokesman for the American Heart Association and professor of cardiology at the University of California, Los Angeles, agrees that most patients with hard-to-control high blood pressure also suffer from sleep apnoea.

“Close to three out of four patients with resistant [high blood pressure] have been found to have obstructive sleep apnoea, and this sleep apnoea may contribute to the difficulty to control the blood pressure in these patients,” he said.

Although this study showed a benefit from CPAP in controlling blood pressure, questions remain about the treatment’s overall effectiveness, Fonarow said.

“Whether these improvements in blood pressure can be sustained in the long term and will translate to improved health outcomes will require additional studies,” he said.

Source: health24

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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