Screening and Treatment of Obstructive Sleep Apnea in Acute Coronary Syndrome: A Randomized Clinical Trial

Obstructive sleep apnea (OSA) is a negative prognostic factor in patients with acute coronary syndrome (ACS), a major cause of heart failure. This randomized controlled trial evaluated the effects of sleep-study guided multidisciplinary therapy (SGMT) 

At two public hospitals in Singapore, patients admitted with ACS were enrolled and randomised into standard therapy (without sleep study) versus SGMT, comprising a sleep study during admission. Those with at least mild OSA were reviewed by a sleep physician and treated with continuous positive airway pressure and behavioural therapy. The primary end point was the change in N-terminal pro-brain natriuretic peptide (NT-proBNP) level from baseline to 7-month follow-up; the secondary end points were the changes in suppression of tumorigenicity 2 (ST2) and high-sensitivity C-reactive protein (hs-CRP) levels.

Among the 159 patients completed the trial, 70 were randomized to the SGMT group. 21 (30%), 15 (22%) and 27 (39%) were diagnosed with mild, moderate and severe OSA, respectively. CPAP and a positional pillow were prescribed to 57 (91%) and 6 (9%) patients with OSA. Average CPAP adherence was 3.8 ± 2.6 hours per night.

Although the plasma NT-proBNP levels were lower after 7 months compared to the baseline, the levels did not differ significantly between the SGMT and standard therapy groups at baseline (579 ± 1117 vs. 611 ± 899 pg/dL, p = 0.851) or 7 months (90 ± 167 vs. 93 ± 174 pg/dL, p = 0.996). The changes in NT-proBNP levels from baseline to 7 months were similar between the SGMT and standard therapy groups (–489 vs. –518 pg/dL, p = 0.726). Similar findings were observed for the ST2 and hs-CRP levels.

OSA screening and multifaceted treatment during the sub-acute phase of ACS did not further reduce the levels of cardiovascular biomarkers when compared with standard therapy.