Adherence to PAP therapy improves survival in hospitalized patients with sleep-disordered breathing
A large database analysis confirms a high incidence of undetected sleep-disordered breathing in obese hospitalized patients in selected medical services. In addition, adherence to therapy and early intervention shows a survival benefit.
“[W]e confirmed that there is a high prevalence of undiagnosed sleep-disordered breathing,” researchers said. “Furthermore, follow-up of these patients for a mean of 609 days demonstrated that those who were adherent to PAP (positive airway pressure) therapy had a survival advantage in comparison with those who were noncompliant.”
A total of 5,062 patients (mean age 60.7 years; body mass index, 34.8 kg/m2; 49.0 percent males) were screened from March 2013 to July 2016. Of these, 1,410 underwent in-hospital overnight high-resolution plethysmography (HRPO) and 680 underwent polysomnography postdischarge. [Am J Med 2017;130:1184–1191]
There were 1,092 patients who had sleep-disordered breathing (oxygen desaturation index [ODI] ≥5) in the HRPO group, whereas 585 patients were sleep-disordered positive (apnoea-hypopnea index [AHI] >5) in the polysomnography group. Based on a receiver operating characteristic curve for ODI derived from HRPO plotted against AHI from polysomnography, the area under the curve was 0.83 for an ODI of >5.
During a mean 609 days of follow-up, patients who adhered to PAP therapy in the first 3 months showed improved survival compared with those who did not adhere to PAP therapy (p=0.01).
The estimated prevalence of undiagnosed sleep-disordered breathing was 18.7 percent in this single-centre database, and the true prevalence rate could be higher if there were patients who screened falsely negative. However, there were much higher estimates of such prevalence in the community, with 83.8 percent of men found to have an AHI ≥5 in one study. [Am J Epidemiol 2013;177:1006–1014; Sleep Med 2010;11:441–446; Am J Respir Crit Care Med 2001;163:685–689; Lancet Respir Med 2016;4:e5–e6]
“It is likely that differences between our results and these general population estimates are related to dissimilarities in population characteristics, methods of ascertainment and definitions of sleep-disordered breathing. Irrespective of the true prevalence rate in hospitalized patients, it appears that there are large numbers of unrecognized sleep-disordered breathing patients in this population,” researchers said.
The significant survival advantage of patients treated and compliant with PAP therapy compared with those who were noncompliant was the major finding of this study.
“We do not believe that differences in various comorbidities explains the observed survival advantage of PAP therapy-adherent patients in that there were few differences in the prevalence of important comorbid conditions between the two groups, and this observation was supported using an inverse propensity score analysis that accounted for differences between the two groups,” researchers said.
A modern world pandemic, sleep-disordered breathing is associated with the development of several cardiovascular conditions, such as congestive heart failure, hypertension, atrial fibrillation and stroke. Some large observational studies have also identified sleep-disordered breathing as a risk factor for premature mortality. [J Cardiol 2014;63:3–8; WMJ 2009;108:246–249; PLoS Med 2009;6:e1000132; J Clin Sleep Med 2014;10:355–362]