Introduction: Arterial stiffness and left ventricle hypertrophy are associated with a decrease in collagen type1 degradation. Aim of our study was to address whether an increase in plasma levels of metalloproteinases-1 (MMP1, responsible for collagen type1 degradation) and her tissue inhibitor (TIMP1) are correlated to the presence of subclinical vascular organ damage (VOD) as defined by ESH-ESC Hypertension guidelines.

Methods: In 251 well-treated hypertensive outpatients (HT, age 57±12.5 years, Blood Pressure,BP,132±18/79±11mmHg mean±SD) we assessed carotido-femoral PWV (Complior) and we measured serum levels of MMP-1 and TIMP-1 (ELISA). Patients were divided in two groups, the first group including those with PWV<12m/sec (NOD) and the second one including patients with PWV ≥12m/sec, indicative of VOD.

Results: 93 patients showed VOD (37%), and 151 NOD (60%). VOD subjects were older than NOD (63±10vs53±12 years, p<0.001), had higher Systolic BP values (141±20 vs. 127±15mmHg, p<0.001) and higher TIMP1 plasma levels (162.27±46.3vs141.98±39.0, p<0,01), while there were no differences in MMP1. Furthermore in the whole population we found a correlation between PWV and TIMP1 (p=0.04, r=0,19), the correlation survived after adjusting for SBP but disappeared adjusting for age.

Discussion: In our study, HT patients with VOD were older and had higher SBP compared with NOD, they had also higher serum levels of TIMP1. Therefore TIMP1 plasma levels might be a further indicator of the cardiovascular aging process that is the first responsible of arterial stiffening.