At-home sleep studies may be noninferior to those at centers

Outcomes for obstructive sleep apnea (OSA) patients tested at home with limited channel sleep-study equipment were not clinically inferior to outcomes in those patients managed with full polysomnography data at a study center, a study found.

Researchers conducted a multicenter, randomized, noninferiority study at seven academic sleep centers in Australia and New Zealand. Four hundred six patients ages 25 to 80 years with suspected OSA were randomized into one of three groups, which determined what sleep study information would be disclosed to treating physicians: level 1 (L1) or laboratory-based polysomnography (n=135), which included electroencephalography, electrooculography, chin and leg electromyography, airflow, thoracoabdominal bands, snoring sensor, body position, electrocardiography (EKG), and oxygen saturation; level 3 (L3) (n=136), which included airflow, thoracoabdominal bands, body position, EKG, and oxygen saturation; or level 4 (L4) (n=135), which included oxygen saturation and heart rate. In level 3 and level 4 testing, fewer recording channels are used without electroencephalography, electrooculography, or electromyography to score sleep stages. Level 2 testing, in which in-home devices record full polysomnography data, was not evaluated in this study.

The primary outcome was change in Functional Outcomes of Sleep Questionnaire score at four months. Secondary outcomes included the Epworth Sleepiness Scale, the Sleep Apnea Symptoms Questionnaire, continuous positive airway pressure adherence, and physician decision making.

Results were published online Jan. 24 by Annals of Internal Medicine.

Change in patients' Functional Outcomes of Sleep Questionnaire score was not inferior for L3 (mean difference, 0.01; 95% CI, −0.47 to 0.49; P=0.96]) or L4 (mean difference, −0.46; 95% CI, −0.94 to 0.02; P=0.058) compared to L1 (noninferiority margin, −1.0). Also compared with L1, the change in Epworth Sleepiness Scale score was not inferior for patients in the L3 group (mean difference, 0.08; 95% CI, −0.98 to 1.13; P=0.89), but results were inconclusive for the L4 group (mean difference, 1.30; 95% CI, 0.26 to 2.35; P=0.015) (noninferiority margin, 2.0). For L4 compared directly to L1, there was less improvement in Sleep Apnea Symptoms Questionnaire scores (−17.8 vs. −24.7; P=0.018), less continuous positive airway pressure use (4.5 vs. 5.3 hours per night; P=0.04), and lower physician diagnostic confidence (P=0.003).

Study results support the use of at-home sleep testing equipment in clinical practice, the authors wrote. “Although the primary outcome was not clinically inferior in patients managed with L4 data, several secondary outcomes seemed to be worse,” the study said. “Thus, although this study provides reassurance about the clinical utility of manually scored L3 studies in the management of patients referred to a sleep clinic with suspected OSA, caution may be needed when using L4 testing.”