Treatment for obstructive sleep apnoea and cardiovascular diseases: are we aiming at the wrong target?

Despite a robust design and good statistical power, the ISAACC study1 (Impact of Sleep Apnea syndrome in the evolution of Acute Coronary syndrome. Effect of intervention with CPAP), similar to the SAVE study (Sleep Apnea cardioVascular Endpoints),2 did not show a positive effect of obstructive sleep apnoea (OSA) treatment with continuous positive airway pressure (CPAP) as a secondary prevention for cardiovascular events. The modest but clinically similar use of CPAP (<3 h per night) observed in this study and in SAVE might explain, at least in part, this absence of an effect. However, when the authors compared participants with acute coronary syndrome (ACS) without OSA (reference group) with participants with ASC and OSA who were given usual care (usual care group, no CPAP), they did not find any significant differenceon the recurrence of cardiovascular events. This intriguing finding raises further questions regarding the effect of OSA on cardiovascular events.