A comparison of home sleep apnea tests (HSAT) or in-lab sleep studies (PSG)
It's essential for sleep technologists to understand how home sleep apnea tests (HSAT) or in-lab sleep studies (PSG) compare to each other in performance and function
- How should HSAT be applied in clinical practice, and are the clinical outcomes similar compared to PSG?
- Is HSAT more cost efficient than an in-lab PSG?
An overview of recent study findings
A study was conducted that sought to compare the functional outcomes and CPAP adherence in patients with suspected OSA by comparing how PSG results compared to HSAT results.
While the authors found that HSAT is as effective in detecting OSA as a traditional PSG test, the study looked at a limited scope of study participants who were almost exclusively middle-aged obese men from two Veterans Health Administration (VA) facilities. However, in another study with a more diverse patient participant group, researchers found more evidence that using a HSAT for diagnosis and treatment of OSA was not inferior to an in laboratory PSG method in regard to CPAP adherence, titration pressures, time to treatment, and functional outcomes.
But which option is more cost effective in the long run? A study finds in favor of PSG
According to this study, in the long run, a full-night PSG is more cost-effective than a split-night and HSAT testing due to “superior diagnostic accuracy” and limiting of false-positive and false-negative studies that result in unnecessary therapies or untreated cardiovascular risk.
More areas of concern for sleep technologists
An Incomplete Measurement: As of today, current HSAT methods do not measure everything that a PSG can. PSG can accurately monitor sleep, blood oxygen levels, respiratory effort and airflow, limb movements, heart rate and body position. However, HSAT can not measure the Respiratory Disturbance Index (RDI), meaning that subtle breathing irregularities are often missed. Furthermore, it has been found that mild to moderate sleep disordered breathing is sometimes missed using home sleep apnea testing.
Patient Errors: HSAT requires a patient to correctly place equipment on themselves. This equipment can be moved during sleep, or be placed incorrectly, which leads to faulty results or no results, meaning significant disorders can be missed.
In addition, patients often err when estimating when they went to sleep, and how long they slept in total. In a sleep center, professionals monitoring the patient can ensure the correct placement of equipment, ongoing integrity of the recording, and the correct measurement of important variables. HSAT does not tell us whether the patient was sleep or what stages of sleep occurred, which is important to assess.
The bottom line
HSAT methods do have a competitive advantage over PSG in that these studies are more convenient for some patients. In the end, the fundamental issue for sleep technologists should be not whether home sleep apnea testing studies are better or worse than PSG, but rather under what conditions use of HSAT is appropriate.
Standards of practice indicate PSG is recommended to a patient if he or she has congestive heart failure, a pulmonary disease or a neuromuscular disease, or another suspected sleep disorder, such as narcolepsy, insomnia, periodic limb movement disorder or a less known variant of sleep apnea called upper airway resistance syndrome (UARS).
At our upcoming Branson meeting, experts will discuss how sleep technologists can successfully navigate the increasing usage of HSAT methods, and identify and get the appropriate patients into the sleep center for appropriate diagnosis and advanced treatment modalities. Sign up by clicking on the image below.