Score One for At-Home Sleep Testing

Vol. 21 • Issue 26 • Page 8

Since 1987, officials running the nation’s Medicare program have reimbursed for continuous positive airway pressure (CPAP), the mainstay therapy for patients diagnosed with obstructive sleep apnea (OSA).

For 21 years, to qualify for reimbursed CPAP, a Medicare patient with OSA had to evidence 30 or more apnea/hypopnea episodes per hour-as documented by sleep techs in a sleep lab, subjecting the patient to a full night of polysomnography (PSG) testing.

Then, on March 13, Medicare reversed course-and stunned the sleep community.

Looking to save money for its beleaguered program and to relieve mounting patient backlogs at sleep centers, Medicare announced it would reimburse for a cheaper, alternative way to diagnose OSA: portable sleep apnea monitoring done in the patient’s home.

Critics stomped all over the ruling. Home testing on a national scale will significantly increase false readings, they said, delaying treatment for millions.

Proponents, though, saw a net positive. Reimbursement for at-home sleep testing will result in more Medicare patients being diagnosed and treated for OSA.

It remains to be seen which view prevails. One thing is certain: Medicare’s decision to cover at-home apnea testing with portable monitors (PMs) “has made some people very happy and others very sad,” noted sleep physician Samuel Kuna, MD.

Head-to-Head Comparison

Medicare may be convinced that PMs are equivalent to in-lab PSG for diagnosing OSA. But researchers are still testing the thesis.

Kuna, chief of pulmonology, critical care and sleep medicine at Philadelphia’s VA Medical Center, is heading up the newest trial to compare the diagnostic prowess of PMs with that of in-lab PSG. Joining Kuna is Charles Atwood, MD, director of the VA Pittsburgh Healthcare System Sleep Disorders Program. Their study of more than 300 OSA patients should be completed by June.

Both physicians treat military veterans, who happen to be ideally suited for sleep medicine research. “We send 50 percent of patients home on portable monitors,” Kuna told ADVANCE. “Very few come back negative. We have a high frequency of apnea. We’re dealing with largely male and overweight individuals.”

Available literature comparing portable and in-lab monitoring has found no significant differences between the two, he said.

Most Type 3 PMs don’t record sleep staging, have no EEG, EOG or ECG capabilities, and “tend to underestimate OSA severity compared to in-lab monitors,” Kuna said. “On the other hand, night-to-night variability is found in in-lab testing using the same equipment in the same environment but on different nights.”

In-lab PSG, he said, remains a “flawed gold standard” for diagnosing apnea-hypopnea indices.

In the wake of Medicare’s precedent-setting ruling, private insurers “will now accept and perhaps even demand portable monitoring for OSA,” Kuna predicted.

Another sign of home sleep testing’s growing sophistication is the emergence of auto-titrating CPAP, or APAP. Investigators want to determine whether APAP, performed unattended in the home, can match in-lab CPAP titration.

This newer generation CPAP “titrates to snoring, apnea/hypopneas and inspiratory flow limitations,” Kuna said. “Many are capable of simultaneous pulse oximetry or interface with a Type 3 PM.”

Atwood said fixed-pressure, lab-titrated CPAP remains the standard, while APAP now comprises about 15 percent of the market.

He referenced a 2004 study that randomized 306 OSA patients to receive either standard in-lab CPAP titration, APAP, or a predicted formula titration with the ability for adjustment at home.

No differences were seen in the objective compliance of CPAP treatment or dropout rate among the three groups.1“The literature now supports equivalency between APAP and fixed-pressure CPAP,” Atwood said. “You should be comfortable and familiar with both” and chose the one that works best for individual patients.


1. Masa J, Jim‚nez A, Dur n J, et al. Alternative methods of titrating continuous positive airway pressure: a large multicenter study. Am J Respir Crit Care Med. (2004; 170, 11: 1218-24).

Michael Gibbons, senior associate editor, can be reached at [email protected].