Kraen M, et al. - Researchers sought to present the epidemiological data concerning the value of matrix metalloproteinases (MMPs) as biomarkers of chronic obstructive pulmonary disease (COPD) and atherosclerosis with special regards to smoking habits. This study comprised 417 middle-aged subjects with records of smoking habits and tobacco consumption who had undergone comprehensive spirometry, carotid ultrasound examination and biomarker analysis of MMP-1, -3, -7, -10 and -12. Outcomes revealed elevated levels of MMP-1 and -MMP-12 among cases with COPD and concomitant plaque in the carotid artery, even after adjusting for risk factors. They recommend considering smoking when interpreting serum MMP results, as it was correlated with higher serum levels of MMPs (except for MMP-3).