Continuous positive airway pressure therapy in non-sleepy patients with obstructive sleep apnea: results of a meta-analysis.

BACKGROUND

Although continuous positive airway pressure (CPAP) has become the first line of therapy for obstructive sleep apnea (OSA), it remains controversial whether non-sleepy patients could benefit from CPAP treatment.

METHODS

We searched the online databases Medline, Embase, the Cochrane library and the Cochrane Central Registry of Controlled Trials to select eligible control trials, including non-sleepy OSA patients and those patients treated by CPAP or either sham CPAP or no CPAP.

RESULTS

Seven eligible studies (1,541 patients) were included. The pooled estimates of the mean changes after CPAP treatment for the systolic blood pressure (SBP) and diastolic blood pressure (DBP) were -0.51 mmHg (95% CI, -3.39 to 2.38 mmHg; P=0.73) and -0.92 mmHg (95% CI, -1.39 to -0.46 mmHg; P<0.001), respectively. CPAP should not improve subjective sleepiness in the minimally symptomatic OSA patients, as the change in the Epworth sleepiness scale (ESS) was -0.51 (95% CI, -1.68 to 0.67; P=0.397). However, CPAP can effectively reduce AHI or ODI by 15.57 events/h (95% CI, -29.32 to -1.82; P=0.026) compared to controls. However, the risk of cardiovascular events did not significantly decrease [odds ratio (OR), 0.80; 95% CI, 0.50 to 1.26; P=0.332] in the end.

CONCLUSIONS

CPAP treatment can reduce OSA severity in non-sleepy patients and minutely reduce the DBP, but CPAP seems to have no overall beneficial effects on subjective sleepiness, SBP, or cardiovascular risk.