The proportion of current smokers at baseline were 17% among the patients with OSA and 26% in no-OSA in the RICCADSA cohort, which makes the current work important to address the determinants of high circulating levels of MPO and MMP-9 in a larger sample of CAD patients with OSA versus without OSA, which has been the main aim of the current study. The gene discussed is MMP9; the disease is obstructive sleep apnea syndrome.