A randomized controlled trial of nurse-led care for symptomatic moderate-severe obstructive sleep apnea.

RATIONALE: Obstructive sleep apnea (OSA) is a prevalent disease. Often limited clinical resources result in long patient waiting lists. Simpler validated methods of care are needed. OBJECTIVES: To demonstrate that a nurse-led model of care can produce health outcomes in symptomatic moderate-severe OSA not inferior to physician-led care. METHODS: A randomized controlled multicenter noninferiority clinical trial was performed. Of 1,427 potentially eligible patients at 3 centers, 882 consented to the trial. Of these, 263 were excluded on the basis of clinical criteria. Of the remaining 619, 195 met home oximetry criteria for high-probability moderate-severe OSA and were randomized to 2 models of care: model A, the simplified model, using home autoadjusting positive airway pressure to set therapeutic continuous positive airway pressure (CPAP), with all care supervised by an experienced nurse; and model B, involving two laboratory polysomnograms to diagnose and treat OSA, with clinical care supervised by a sleep physician. The primary end point was change in Epworth Sleepiness Scale (ESS) score after 3 months of CPAP. Other outcome measures were collected. MEASUREMENTS AND MAIN RESULTS: For the primary outcome change in ESS score, nurse-led management was no worse than physician-led management (4.02 vs. 4.15; difference, -0.13; 95% confidence interval: -1.52, 1.25) given a prespecified noninferiority margin of -2 for the lower 95% confidence interval. There were also no differences between both groups in CPAP adherence at 3 months or other outcome measures. Within-trial costs were significantly less in model A. CONCLUSIONS: A simplified nurse-led model of care has demonstrated noninferior results to physician-directed care in the management of symptomatic moderate-severe OSA, while being less costly. Clinical trial registered with http://www.anzctr.org.au (ACTRN012605000064606).

The effect of CPAP in normalizing daytime sleepiness, quality of life, and neurocognitive function in patients with moderate to severe OSA.

STUDY OBJECTIVES: The study aimed to document the neurobehavioral outcomes of patients referred to and treated by a sleep medicine service for moderate to severe obstructive sleep apnea (OSA). In particular, we aimed to establish the proportion of patients who, while appearing to have optimal continuous positive airway pressure (CPAP) adherence, did not normalize their daytime sleepiness or neurocognitive function after 3 months of CPAP therapy despite effective control of OSA. DESIGN: Multicenter clinical-effectiveness study. SETTING: Three academic sleep centers in Australia. PARTICIPANTS: Patients referred to a sleep medicine service with moderate to severe OSA (n = 174). INTERVENTION: CPAP. MEASUREMENTS AND RESULTS: Participants were assessed pretreatment and again after 3 months of CPAP therapy. At the beginning and at the conclusion of the trial, participants completed a day of testing that included measures of objective and subjective daytime sleepiness, neurocognitive function, and quality of life. In patients with symptomatic moderate to severe OSA (i.e., apnea-hypopnea index > 30/h), we found a treatment dose-response effect for CPAP in terms of Epworth Sleepiness Scale scores (P < 0.001). Several key indexes of neurobehavior (e.g., Functional Outcomes of Sleep Questionnaire, Epworth Sleepiness Scale) currently used to assess treatment response failed to normalize in a substantial group of patients after 3 months of CPAP treatment, even in those who were maximally compliant with treatment. Forty percent of patients in this trial had an abnormal Epworth Sleepiness Scale score at the conclusion of the trial. In addition, we showed no dose-response effect with the Maintenance of Wakefulness Test, raising doubts as to the clinical utility of the Maintenance of Wakefulness Test in assessing treatment response to CPAP in patients with OSA. CONCLUSIONS: Our study suggests that a greater percentage of patients achieve normal functioning with longer nightly CPAP duration of use, but a substantial proportion of patients will not normalize neurobehavioral responses despite seemingly adequate CPAP use. It is thus crucial to adequately assess patients after CPAP therapy and seek alternate etiologies and treatments for any residual abnormalities.