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CPAP treatment for obstructive sleep apnea without daytime sleepiness does not reduce CVD

Clinical Question:
Is continuous positive airway pressure effective for reducing the incidence of hypertension and cardiovascular disease in adults with obstructive sleep apnea without daytime sleepiness?

Bottom Line:
Continuous positive airway pressure (CPAP) did not result in a significant reduction in the incidence of hypertension and cardiovascular events in adults with obstructive sleep apnea without daytime sleepiness. Patients with CPAP adherence of 4 hours per night or longer did have a significantly reduced risk of incident hypertension and cardiovascular disease compared with control patients. It is uncertain, however, whether this is a true benefit of CPAP, or a result of the "compliance effect," whereby compliant patients will almost always experience a significant reduction in morbidity and mortality when compared with a mixed population of both compliant and noncompliant individuals. (LOE = 1b)

Barbé F, Durán-Cantolla J, Sánchez-de-la-Torre M,et al, for the Spanish Sleep and Breathing Network. Effect of continuous positive airway pressure on the incidence of hypertension and cardiovascular events in nonspleepy patients with obstructive sleep apnea. A randomized controlled trial. JAMA 2012;307(20):2161-2168.  [PMID:22618923]

Study Design:
Randomized controlled trial (double-blinded)



Outpatient (any)

Evidence from observational studies supports the benefit of CPAP in reducing the incidence of cardiovascular disease in adults with severe and moderate symptomatic obstructive sleep apnea. However, whether there is a benefit for CPAP treatment in nonsleepy patients is uncertain. These investigators identified patients, aged 18 years to 70 years, who were referred to sleep units for evaluation of observed apneas or snoring and met standard diagnostic criteria for sleep apnea but without daytime hypersomnolence defined by a daytime sleepiness rating scale. Patients with and without a history of hypertension were included. Eligible patients randomly received (concealed allocation assignment) CPAP treatment or no active intervention. Individuals assessing outcomes remained masked to treatment group assignment. Complete follow-up occurred for 83% of participants for up to 5.38 years. Using intention-to-treat analysis, there was no significant difference in the incidence rate for hypertension or cardiovascular events bewteen the CPAP group and the no-intervention group. Disease severity as assessed by the number of nighttime apneas or lowering of oxygen saturation percent was also not related to the incidence of cardiovascular disease. However, in a post-hoc analysis, the incidence of hypertension and cardiovascular events among patients using CPAP for at least 4 hours per night was significantly reduced compared with the no-intervention group, despite that group’s higher body mass incex, larger neck circumference, higher incidence of hypertension, and greater apnea-hypopnea index. The study was 90% powered to detect a predetermined clinically significant difference between the treatment and control groups.


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