Obstructive sleep apnea and other sleep disorders have long been associated with cognitive dysfunction, but so far not in a prospective study. So, Yaffe et al followed 298 older women (~82 years) who had already had polysomnography as part of an osteoporosis study. 105 had sleep disordered breathing (cases), defined as an apnea-hypopnea index >= [… read more]
A minority of people develop central sleep apneas during polysomnography with continuous positive airway pressure titration for obstructive sleep apnea. Others develop central apneas later, discovered on interrogation of their CPAP machine. The fact is, no one knows much about this so-called complex sleep apnea — its natural course, prognosis / risks, and whether or [… read more]
Kuniyoshi et al prospectively observed people admitted to Mayo for myocardial infarction, performing polysomnography and measuring flow-mediated dilation in their brachial arteries. A whopping 69% (45 of 64) were found to have obstructive sleep apnea. Those with moderate to severe OSA had poorer arterial responsiveness, a surrogate marker for subsequent cardiovascular risk, compared to people [… read more]
Teo et al randomized 24 people with newly diagnosed obstructive sleep apnea (AHI > 15) to crossover between nasal and oronasal (full-face) masks during 2 consecutive nights of CPAP titration. The nasal mask had more leaks and people wearing it had more arousals. However, they liked it better than the face mask, and there was [… read more]
Flexible pressure CPAP reduces pressure briefly during expiration, to try to make it more comfortable. Bakker & Marshall meta-analyzed 10 randomized trials in >500 patients testing flexible pressure vs standard CPAP in people with obstructive sleep apnea; there were no differences in compliance or any other outcome. CHEST 2011;139:1322-1330.
Update in sleep medicine 2010. Mokhlesi B, Gozal D. AJRCCM 2011;183:1472-1476. Sleep review.
Lee et al report phase III trial results for this prodrug of gabapentin. It improved symptoms in people with moderate-to-severe RLS at the end of 12 weeks, compared to placebo. However, time (placebo) also worked well. The FDA approved the drug for moderate-to-severe RLS in April 2011. J Clin Sleep Med 2011;7:282-292.
In 63 Swedish men with obstructive sleep apnea, a one-year weight loss program initiated by a supervised 9-week crash diet resulted in a ~12 kg weight loss. At one year, patients’ apnea-hypopnea index improved by ~17 events / hour; 48% no longer needed CPAP, and 10% were cured. The more weight lost, the greater the [… read more]
Allen et al surveyed 266 people under treatment for RLS for symptoms of augmentation. Fully 20% treated for ~2.7 years had definite or very likely augmentation; only 25% were completely free of augmentation symptoms, as assessed using NIH guidelines. Sleep Med 2011;12:431-439.
Bitter et al performed CPAP titration on 192 patients with congestive heart failure and obstructive sleep apnea, unmasking residual central sleep apnea (so-called complex sleep apnea) in 34 (18%). Providing adaptive servoventilation (dynamic delivery of pressure support to achieve a target minute ventilation) improved AHI, NYHA class, BNP levels, ejection fraction, and other variables, at ~1 year [… read more]
Canessa et al observed 17 people with untreated obstructive sleep apnea and 15 age-matched healthy controls, performing sleep studies, cognitive testing, and MRIs on all. At baseline, OSA patients had shrinkage in brain areas responsible for memory and executive function (hippocampus, posterior parietal cortex, and superior frontal gyrus, as quantitated by voxel based morphometry) and were neurocognitively impaired [… read more]
Kuna et al randomized 296 veterans with suspected obstructive sleep apnea (OSA) to home sleep testing with a type 3 portable monitor followed by auto-titrating CPAP, or in-lab polysomnography and CPAP titration. After 3 months of CPAP treatment (in the 260 or 88% overall who did have OSA), surveyed functional outcomes were identical between groups, [… read more]
Parra et al diagnosed OSA in 140 patients hospitalized for stroke in Spain and randomized them to nasal auto-titrating CPAP or no therapy. The CPAP-treated patients had better Rankin and Canadian stroke outcome scores at all follow-up visits. They had the same rate of subsequent cardiovascular events, but events occurred at a median 15 months [… read more]
Nocturnal monitoring of home non-invasive ventilation: Janssens JP, Thorax 2011;66:438-445. Sleep and obesity hypoventilation review.
Non-CPAP therapies in obstructive sleep apnea, European Respiratory Society task force statement. ERJ 2011;37:1000-1028. Sleep review, OSA review.
Sleep medicine training across the spectrum, Strohl KP, CHEST 2011;139:1221-1231. Sleep review.
Patients taking pramipexole for 6 months had a 14-point fall in their IRLS score, and 59% “responded” (had at least a 50% fall in their score). But time worked well, too: placebo patients had an 11-point decline in scores and 43% responded. So 1 in 6 responded to pramipexole, practically speaking (they don’t say this, [… read more]
Fen-phen died in court, but phenteramine was cleared of all serious charges. Gadde et al report phase III results for Qnexa (by Vivus), a phenteramine-topiramate combination. Over 56 weeks, takers of a double-dose of study drug lost 10 kg; single-dose, 8 kg; and placebo, 1.4 kg. There were plenty of side effects (dry mouth and paresthesias [… read more]
Gooneratne et al selected 289 people over 65 (nondemented, nondepressed), half of whom had excessive daytime sleepiness (EDS). All got polysomnograms and were followed for a mean of 14 years. Those with EDS and sleep disordered breathing (SDB) had a hazard ratio for mortality of 2.7, that fell to 2.3 after adjusting for covariates. People [… read more]
Sleep medicine, a 3,000-year history: Kirsch DB, CHEST 2011;139:939-946.