Home Sleep Testing - Provider FAQs
Previously, home sleep testing (HST) was considered an unproven technology and most third party payors would not cover treatment with continuous positive airway pressure (CPAP) when the diagnosis was made using a HST device, nor, in most cases, pay for the testing itself.
In March, 2008, Centers for Medicare and Medicaid Services (CMS) issued a National Coverage Determination (NCD) policy stating the evidence supported use of HST to establish the diagnosis of obstructive sleep apnea (OSA) in some patients and they would cover CPAP treatment based on that diagnosis.
In addition, payment by Medicare for CPAP for longer than 3 months requires documentation of improvement of the patient’s OSA. This mandates demonstration of effectiveness of treatment. In the NCD, CMS left development of guidelines for selection of patients and demonstration of improvement to the regional carriers.
Medicare placed new emphasis on making sure patients benefit from CPAP therapy. They felt there was sufficient data that the method of diagnosing OSA in certain patients was comparable and the method of diagnosis did not influence response to therapy. After the diagnosis of OSA is made, they emphasized the need to monitor and demonstrate that patients are using CPAP and benefiting from treatment.
At this time, there is no definition as to what will constitute compliance or treatment benefit. The NCD has left that determination to local carriers.
Eligibility and Screening
HST should be utilized only as part of a comprehensive sleep evaluation. Sleep HealthCenters (SHC) can conduct an evaluation to determine if the patient is appropriate for HST. The referring provider can order the test if they determine the patient meets criteria for HST.
The answer to this question is insurance provider-dependent. NHIC, the regional Medicare carrier for Massachusetts Part B (IDTFs and Physicians), issued a Local Coverage Determination (LCD) in March 2008, limiting the diagnosis of OSA to the in-laboratory setting. Aetna, Fallon and NHP have issued guidelines allowing HST for the diagnosis of OSA. In the next 6 months, other groups are likely to follow the NCD, including NHIC.
The American Academy of Sleep Medicine (AASM) has published suggested guidelines for the use of HST in the diagnosis of OSA. They recommend that HST be used only in the context of a comprehensive sleep evaluation and for the following patients:
The AASM recommended that HST is not appropriate for general screening of asymptomatic patients.
Is there a screening tool for the referring provider to use to determine who is a good candidate for HST?
A useful formula for estimating patients at high risk for moderate to severe OSA:
It is a formula used to predict the likelihood of having moderate to severe OSA. It incorporates several of the most common risk factors for OSA, including neck size (a marker of obesity), the symptoms of snoring and gasping at night and the presence of hypertension.
The Epworth Sleepiness Scale and answer key is below. Circle answers and tally up numbers to get score.
HST vs. PSG
In patients with a high pre-test likelihood of moderate to severe OSA, HST is comparable to in-laboratory PSG. HST tends to underestimate severity of OSA compared to in-laboratory PSG but has similar likelihood ratios for detecting the presence of OSA.
HST is used only to look for obstructive sleep apnea. Only 4-5 channels of physiologic data regarding respiration are obtained, as opposed to 14 channels during in-lab polysomnography.
Information on sleep stages and EEG is not obtained with HST. As a result, HST may underestimate the severity of OSA. If the HST is negative in a patient suspected of having OSA, the patient should have an in-lab PSG for confirmation.
You cannot determine amount of sleep with an HST. At least 2 hours of recording time is needed to make a diagnosis of OSA. Because of these limitations, HST should be performed and interpreted by someone trained and competent in using the devices.
These describe the different types of sleep monitors and the level is determined by the number of physiologic channels measured.
A recent CMS-commissioned Agency for Health Research and Quality (AHRQ) report found that portable monitors were able to predict an AHI suggestive of OSA with high positive likelihood ratios and low negative likelihood ratios. HST devices tend to under estimate the AHI because they do not measure sleep time but rather recording time.
Depending on the level and the specific device, they measure some combination of airflow, respiratory effort, oximetry, heart rate and/or snoring.
What portable monitors are on the market? How do they differ?
There are a wide variety of devices on the market, however, there is no data suggesting one portable monitor is superior to another. They differ by the number and type of physiologic channels measured.
For HST, SHC will use the following, as recommended by the AASM:
A Stardust® II Sleep Recorder from Respironics, Inc.
Stardust is a Level 3 device that meets all the specifications recommended by the American Academy of Sleep Medicine Clinical Guideline for the Use of Portable Monitors.
We have been using Stardust for many years and are quite familiar with its use and limitations. It is already fully compatible with our other sleep diagnostic equipment and software and we can use the same report templates we currently use with little modification. The cost to us of using the device is lower than other devices.
Additionally, our patients have found it easy to use.
The Stardust has 4 channels:
The Stardust also records:
The Stardust does not record EEG.
Ideally, patients are referred for an evaluation by a sleep specialist who can decide if a patient is appropriate for HST. If appropriate, the patient is given a device and instructed how to put it on by a sleep technologist. The patient returns or mails the device back to the center the following day. The study is scored and interpreted by a sleep specialist. The patient returns the following week to see the sleep specialist, who reviews the result of the study with the patient and selects appropriate treatment.
If the referring physician thinks the patient is appropriate for HST but wants SHC to manage the patient, they can send the patient for a 24-hour turnaround service. The patient picks up the device in the afternoon/evening with instruction on its use from the sleep technologist. The patient returns to the clinic with the device the next day and during the same visit the study is scored and interpreted, the sleep specialist reviews the study with the patient, the type of treatment is selected and treatment is initiated, all in the same visit.
If the referring physician thinks the patient is appropriate for HST and wants to manage the patient themselves, they can order the test and receive back a report interpreted by a sleep specialist. SHC will be able to assist with treatment if desired by the referring physician.
We instruct patients how to use the devices in our facilities and they take them home. Only patients unable to come to a center are set up at home.
Patients are given a 24-hour number to call if they are having problems with their devices.
Brighton, Framingham, Medford and Weymouth, Massachusetts.
Managing the Patient
If a patient has a “positive” HST, will the patient then need a full night titration or can they just come in for a setup?
The patient will either need a titration study to determine the optimal CPAP setting or have the optimal pressure determined using an auto titrating CPAP device in their home. If the patient is using an auto titrating device at home, they will return the machine after one week and convert to CPAP machine.
What happens if the HST shows a negative result, but the patient continues to have symptoms of a sleep disorder?
Because HST may underestimate OSA compared to in-laboratory PSG, a negative HST result in a patient with a high pretest suspicion for OSA (the type of patient who should be getting HST) should be followed by in-laboratory PSG to confirm the results.
Split night studies cannot be done with HST. If the HST shows the patient has OSA, that patient can either undergo an in-laboratory CPAP titration study or a home CPAP titration using an auto titrating CPAP machine that can be used to determine the optimal CPAP pressure. If the patient is using an auto titrating device at home, they will return the machine after one week and convert to CPAP machine.
Ideally, the patient should discuss the results with a sleep specialist who is knowledgeable about sleep disorders, HST interpretation and the variety of sleep disorders. All tests should be discussed directly with the patient by a physician.
If the test is positive for OSA the patient should have a comprehensive treatment plan made, including the best method for treating OSA, risk factor modification and improvement in sleep habits. If CPAP is selected as treatment, a compliance program should be developed and implemented. This includes frequent early follow-up to assure proper utilization, improvement in symptoms and resolution of side effects and adverse effects, if any. Ongoing follow-up is necessary to assure long-term compliance with therapy.
There are currently no regulations specifying qualifications of companies doing HST. We recommend using companies associated with an American Academy of Sleep Medicine accredited sleep center to ensure the highest possible quality.
Medicare has stated verbally that they do not want DME companies performing HSTs.
Yes. At Sleep HealthCenters, all studies are reviewed by a board-certified sleep specialist.
No. However, at SHC, all studies are reviewed by a board-certified sleep specialist.
As of 4/21/08: