DENVER – Home ambulatory peripheral arterial tonometry is an accurate, convenient, and far less costly alternative to polysomnography in the sleep laboratory for diagnosis of obstructive sleep apnea, Donald Townsend, Ph.D., said at the annual meeting of the Associated Professional Sleep Societies.
He reported on 103 consecutive patients who presented to a sleep clinic with symptoms suggestive of obstructive sleep apnea.
The patients were randomized to receive overnight home peripheral arterial tonometry (PAT) or standard polysomnography in the sleep clinic, Dr. Townsend reported.
Test results were available the next morning, and the 86% of patients who were in each study arm who were diagnosed with obstructive sleep apnea then received continuous positive airway pressure.
The cost of diagnosis was $653 per patient in the PAT group, compared with $2,181 in the polysomnography group, according to Dr. Townsend, who is with the Metropolitan Sleep Disorders Center, St. Paul, Minn.
Obstructive sleep apnea was deemed sufficiently severe in eight patients based upon PAT results that they required confirmatory testing via polysomnography, which is considered the standard for diagnosis of the disorder.
In a follow-up survey, patients in both study groups indicated a high degree of satisfaction with the testing procedures. At 8 weeks, patients in both groups showed similar significant improvements in scores on the Epworth Sleepiness Scale and Beck Depression Inventory.
PAT measures changes in peripheral arterial tone in response to bursts of sympathetic nervous system activity.
The spikes in sympathetic activity are triggered by arousals from sleep as a result of apneic episodes. PAT is recorded using a device worn on the wrist.
A practical obstacle to wider diagnostic use of PAT is that insurance coverage for the ambulatory test is mixed.
Many insurers continue to be reluctant to reimburse for anything other than overnight polysomnography in the sleep laboratory, although this situation is changing in light of the significant cost savings obtained with PAT, Dr. Townsend explained.
Dr. Townsend's study received no external funding.
However, the Metropolitan Sleep Disorders Clinic has an exclusive arrangement with Itamar Medical, maker of the PAT device, to manage the device in the Twin Cities area.
