Institute for Continuing Education

The Evolution of Portable OSA Monitoring

Course Objectives

Upon successful completion of this module, you will be able to:

• Define OSA
• List the various roles played by monitoring equipment with regard to OSA
• List the key steps in the “evolution” of portable monitoring of OSA
• List the key elements of the newly approved Clinical Practice Guidelines for Portable Monitoring for Diagnosing Obstructive Sleep Apnea

Course Information

In this module, the authors retrospectively evaluated patients who had been referred to their sleep laboratory after undergoing a home sleep study with a portable device (SNAP; SNAP Laboratories; Glenview, IL). The home sleep study had been ordered by each patient’s primary care physician. The results show that the SNAP results frequently differed considerably from the polysomnography results. In approximately 65% of the patients studied, the severity of sleep apnea had been misclassified by the SNAP device relative to polysomnography! These differences included both “overdiagnoses” and “underdiagnoses,” and have the potential for serious ramifications.

Obstructive sleep apnea (OSA) is a highly prevalent disease with estimates that 20% of white men and women with body mass index between 25 and 28 kg/m2 have an apnea-hypopnea index (AHI) of 5.1 In recent years, OSA has been associated with a number of common morbid conditions, including heart disease, stroke, diabetes, and motor vehicle accidents. These links and the fact that the disease is readily treatable with nasal continuous positive airway pressure (CPAP) have accelerated the need for prompt and accurate diagnosis.