Acetazolamide Improved Obstructive Sleep Apnea at High Altitudes by Blair Westerly, MD Obstructive sleep apnea (OSA) is common, and so is travel to the mountains for work and play, therefore encounters with patients with OSA who travel to mountain destinations is not infrequent. We all learn early in training that altitude affects oxygenation, and patients [... read more]
Visual learners can see continuous positive airway pressure (CPAP) work for obstructive sleep apnea in realtime in this NEJM video. But how on earth does someone sleep inside an MRI machine? See the Sleep Apnea Video
CPAP Improves Metabolic Syndrome in Obstructive Sleep Apnea Continuous positive airway pressure (CPAP) therapy reversed elements of the high cardiovascular risk profile known as metabolic syndrome in a substantial minority of Indians with treatment-naive obstructive sleep apnea, according to this article in the New England Journal of Medicine. More than 75% of people with obstructive [... read more]
Most people with mild to moderate obstructive sleep apnea (OSA with AHI of 5 to 30) have no bothersome daytime symptoms. In fact, less than a third (28%) experience daytime sleepiness that impairs their daily functioning (Epworth score > 10). No one had ever shown whether treatment with continuous positive airway pressure (CPAP) improves daytime [... read more]
Obstructive sleep apnea (OSA) might be the perfect disease to describe the American health care system. The condition is overwhelmingly due to our over-indulgence and under-activity; its expensive diagnosis (polysomnography) and best treatment (CPAP) help physicians and device manufacturers prosper while consternating those who pay (the government and insurance companies), who then threaten to cut off [... read more]
Want to keep up with sleep, without falling asleep? We’ll try to make it easy for you: Here are some of the latest and most notable articles in sleep medicine. (This summary will be updated and re-posted as new research is published. Please suggest articles for inclusion in the comments or by email.) Obstructive Sleep [... read more]
Provent is the trade name for disposable, stick-on nose plugs made by Ventus Medical that are a relatively new (second-line) treatment for obstructive sleep apnea. The bandage-like device has pinholes cut in the nostrils that let air in during inspiration, but create back pressure during exhalation, helping prevent airway collapse. The New York Times just [... read more]
Sleep docs don’t come off looking so hot in this recent NPR story, which paints some of them as opportunistic plunderers of the nation’s health care dollars, over-ordering expensive sleep studies to make a buck. As reporter Jenny Gold points out, the number of sleep studies performed in the U.S. has quadrupled over the past [... read more]
Diaphragmatic dysfunction can result from nerve damage, primary muscle problems, or problems with the muscle’s interaction with the chest wall. The true incidence of diaphragmatic paralysis is unknown, since many patients are asymptomatic. Treatment for diaphragmatic dysfunction usually consists of watchful waiting, addressing underlying causes, with mechanical ventilation if respiratory failure develops. Causes of Diaphragmatic [... read more]
Mayo investigators reported back in 2001 that people with obstructive sleep apnea had a higher rate of perioperative complications including hypoxia and longer lengths of stay. Since then, there have been other signals that this is a real phenomenon, but perhaps surprisingly, the evidence hasn’t exactly piled up to unequivocally prove the intuitive point. That’s [... read more]
In the face of criticism from insurers and the government for a perceived excessive zeal for profits, and mounting evidence that uncomplicated obstructive sleep apnea (OSA) can be diagnosed at home and managed by primary physicians, you can’t blame sleep specialists for feeling down-in-the-mouth lately. Sushmita Pamidi et al report some brighter news in the [... read more]
Here’s a great example of how weak findings in small, underpowered studies — findings which should be at most viewed as hypothesis-generating — become transmuted into Serious Studies With Important Implications when the lay press give them too much credit. In this case, the Los Angeles Times, Huffington Post, and CNN took the bait after [... read more]
Hypertension and obstructive sleep apnea are both highly prevalent, and share risk factors, so unsurprisingly, most people with OSA have HTN. This overlap has made it fiendishly hard to determine if OSA actually causes HTN. The widespread belief that OSA causes HTN was creeping close to dogma, egged on by cross-sectional studies that suggested an [... read more]
Did you ever wonder what that police officer is really doing while you wait forever in your car for him to write you your ticket? According to new research, it’s possible he’s taking a quick nap. And you’d best save your snarky comment when he brings you the citation: sleepy cops, it turns out, tend to be [... read more]
One thing I thought I knew was that overweight and obesity cause coronary artery disease and make it worse. People with CAD who are obese should lose weight … right? Recent research shows it’s not that simple (although the answer is still “yes, probably”). Did you know about the “obesity paradox?” Or the “lean paradox,” [... read more]
Mah et al followed 11 Stanford varsity basketball players for ~7-10 weeks. During the first ~3 weeks, players maintained their usual sleep schedules. For the next ~6 weeks, they were encouraged to sleep as long as possible each night, with a goal of 10 hours in bed. After the sleep extension period, their shooting accuracy [... read more]
Carter et al followed 244 children in New Zealand from birth to age 3-7. Between ages 3-5, each additional hour of sleep was associated with a 0.48 reduction in BMI, and a 61% reduction in the risk of being obese or overweight by age 7, after controlling for multiple covariates. BMJ 2011;342:d2712. FREE FULL TEXT
Wijesinghe et al randomized and crossed-over 24 people who were recently diagnosed with obesity hypoventilation syndrome to breathe either 100% oxygen or room air for 20 minutes on 2 separate days, while measuring their minute ventilation, expired tidal pCO2, and dead space-to-tidal volume ratio. In 44% of patients, pCO2 increased by at least 4 mm [... read more]
Obesity Hypoventilation Syndrome: Piper AJ, AJRCCM 2011;183:292-298.
If you spend your nights lying awake worrying about having a heart attack, you’re entirely justified. But you’re probably just making it more likely. Lars Laugsand et al followed 52,610 Norwegian people for 11 years after the subjects completed an initial survey (investigators can do this in Norway, since they’ve got everyone’s health records in [... read more]