Home respiratory polygraphy had similar efficacy with substantially lower per-patient cost, compared with traditional polysomnography for diagnosing obstructive sleep apnea, a study showed.
Obstructive sleep apnea (OSA) is a common chronic disease associated with higher risk of cardiovascular disease and traffic accidents and a lower quality of life. Although expensive and time intensive, the polysomnography (PSG) has been the preferred test for diagnosing OSA. Home respiratory polygraphy (HRP) uses portable devices that are less complex than polysomnography and has been shown to have similar effectiveness in diagnosing OSA, compared with PSG, in patients with a high clinical suspicion of OSA. However, there is limited evidence for the cost effectiveness of HRP, compared with PSG (Am J Respir Crit Care Med. 2017 Nov 1;196:1181-90).
The investigators conducted a multicenter, randomized controlled, noninferiority trial and cost-effectiveness analysis comparing PSG with HRP. Inclusion criteria included snoring or observed sleep apnea, Epworth Sleepiness Scale ()of 10 or higher, and no suspicion of alternative causes for daytime sleepiness. Patients with a suspicion for OSA were randomized to polysomnography or respiratory polygraphy protocols. Both arms received counseling on proper sleep hygiene; counseling on weight loss, if overweight; and auto-CPAP titration if continuous positive airway pressure (CPAP) was clinically indicated.
Assessment of CPAP compliance or dietary and sleep hygiene compliance was assessed at months 1 and 3. ESS, quality of life measures, well-being measures, 24-hour blood pressure monitoring, auto accidents, and cardiovascular events were assessed at baseline and at month 6.
CPAP treatment was indicated in 68% of the PSG arm, compared with 53% of the HRP arm. After intention-to-treat analysis, there was no statistically significant difference between the two groups for ESS improvement (HRP mean, –4.2, vs. PSG mean, –4.9; P = .14). The groups demonstrated similar results for quality of life, blood pressure, polysomnographic assessment at 6 months, CPAP compliance, and rates of cardiovascular events and accidents at follow-up.
The cost-effective analysis demonstrated respiratory polygraphy was less expensive, saving more than 400 euros/patient. “Because the effectiveness (ESS and QALYs [quality-adjusted life-years]) was similar between arms, the HRP protocol is preferable due to its lower cost,” the authors wrote.
In all, 430 patients were randomized to HRP or PSG and consisted mostly of men (70.5%) with a mean body mass index of 30.7 kg/m2. The groups had similar rates of alcohol consumption and hypertension.
Limitations of the study included unblinded randomization to the participants and researchers and the possibility of variability in therapeutic decisions. However, the authors noted that intraobserver variability was minimized by using the Spanish Sleep Network guidelines and centralized assessment.
“[The] HRP management protocol is not inferior to PSG and presents substantially lower costs. Therefore, PSG is not necessary for most patients with suspicion of OSA. This finding could change established clinical practice, with a clear economic benefit,” the authors concluded.
Home respiratory polygraphy continues to impress
This study adds strong evidence to support the use of home respiratory polygraphy for the diagnosis of obstructive sleep apnea in patients without major comorbidities such as severe chronic restrictive or obstructive lung disease, heart failure or unstable cardiovascular disease, major psychiatric diagnoses, and neuromuscular conditions, noted Ching Li Chai-Coetzer, MBBS, PhD, and R.
Doug McEvoy, MBBS, MD, in an accompanying editorial (Am J Respir Crit Care Med. 2017 Nov 1;196:1096-8). However, lower-cost methods to diagnose OSA would still not address unmet needs such as the cost of continuous positive airway pressure and scarcity of sleep physicians to assess patients with OSA, and still may be too expensive for underresourced populations, they said.
Dr. Chai-Coetzer and Dr. McEvoy are affiliated with the Adelaide Institute for Sleep Health at Flinders University and the Sleep Health Service, Southern Adelaide Local Health Network, both in South Australia.
The study was supported by Sociedad Española de Neumología, Air Liquide (Spain), Asociacion de Neumologos del Sur, and Sociedad Extremeña de Neumología. The investigators report no disclosures.
Dr. Chai-Coetzer reported grants from National Health and Medical Research Council of Australia and nonfinancial support from Biotech Pharmaceuticals. Dr. McEvoy reported grants and nonfinancial support from Philips Respironics, nonfinancial support from ResMed, and grants from Fisher & Paykel.