August 2010

Summer Bulletin Online Now
The Summer edition of our Section Bulletin is ONLINE now, with great articles on central sleep apnea and complicated breathing patterns, why everyone is an educator, and sleep deprivation.

Study Links Air Pollution to SDB
A new study out of Brigham and Women’s Hospital and the Harvard School of Public Health has for the first time established a link between air pollution and sleep disordered breathing (SDB). The investigation involved more than 3000 people taking part in the Sleep Heart Health Study. Linear regression models that controlled for seasonality, mean temperature, and other factors known to be associated with SDB, such as age, gender, and smoking, were conducted to gauge the association. A separate seasonal analysis was performed as well. Results linked short-term elevations in temperature with increases in the respiratory disturbance index (RDI). Increases in PM10 during the summer months were also associated with an increase in the RDI, along with an increase in the percentage of sleep time with an oxygen saturation below 90% and a decrease in sleep efficiency. Similar results were not seen during other seasons. The study was published in a recent issue of the American Journal of Respiratory and Critical Care Medicine. READ PRESS RELEASE READ FULL PAPER

Even Mild SDB May Raise Cardiovascular Disease Risk
Another study in the American Journal of Respiratory and Critical Care Medicine looked at the relationship between morning and evening levels of three pro-thrombotic markers—plasminogen activator inhibitor-1 (PAI-1), fibrinogen, and D-dimer—and SDB severity as defined by the apnea/hypopnea index (AHI) in 537 subjects. After controlling for variables, the Case Western Reserve School of Medicine researchers found for every 5-unit increase in AHI under 15, there was a corresponding significant increase of about 10% in PAI-1, and an increase in fibrinogen of about 8.4 mg/dL. D-dimer did not increase significantly in relation to the AHI. “These data suggest that individuals with even modest levels of SDB (which describes a large proportion of the adult population) may have an enhanced pro-thrombotic biochemical profile, increasing their CVD risk,” study author Reena Mehra, MD, MS, was quoted as saying. READ PRESS RELEASE READ FULL PAPER

Sleep Disorders Could be an Early Warning Sign of Neurological Conditions
Could sleep disorders be a precursor to dementia or Parkinson’s disease? A new study in Neurology suggests they might. Researchers who used Mayo Clinic records identified 27 people who experienced rapid eye movement sleep behavior disorder for at least 15 years before developing one of three conditions: Parkinson’s disease, dementia with Lewy bodies, or multiple system atrophy. The time between the start of the sleep disorder and the symptoms of the neurologic disorder averaged 25 years, and in some cases was as long as 50 years. Among the subjects, 13 were diagnosed with dementia, 13 with Parkinson’s disease, and one with multiple system atrophy. READ PRESS RELEASE

Visual Scale Measures HRQL in Sleep Apnea Patients
Spanish researchers publishing in this month’s Sleep & Breathing find good results for a simple visual analogical well-being scale (VAWS) used to gauge health-related quality of life (HRQL) in patients with sleep apnea-hypopnea syndrome (SAHS). They validated the scale in patients who had been treated with CPAP for 12 weeks, finding it correlated with other HRQL tests. They conclude, “VAWS is a very simple test which measures HRQL in SAHS. It could be a useful tool in clinical practice, primarily for the responsiveness of treatment.” READ ABSTRACT