Introduction: The aim of our study was to investigate whether collagen degradation is altered in participants with masked hypertension and whether this alteration could be related to disturbances in the matrix metalloproteinases plasma concentration and to compare the findings with those participants with normal blood pressure levels matched for age, sex, and body mass index.
Methods: Twenty-four (11 men, 13 women) participants with masked hypertension [mean age 46 +/- 7 years and body mass index 25.9 +/- 2.1 kg/m(2) (group A)] and 106 healthy normotensives (49 men, 57 women) with normal blood pressure [mean age 44 +/- 6 years and body mass index 25.5 +/- 2.4 kg/m(2) (group B)].
Results: The plasma levels of matrix metalloproteinase-9 were significantly higher, while the levels of tissue inhibitors of metalloproteinases-1 and -4 were significantly lower in group A compared with group B (matrix metalloproteinase-9: 569 +/- 135 vs. 282 +/- 117 ng/mL, TIMP-1: 169 +/- 42 vs. 230 +/- 37 ng/mL, P < .01, and TIMP-4: 2.1 +/- 1.3 vs. 4.2 +/- 1.98 ng/mL, P < .04, respectively).
Conclusions: Patients with masked hypertension had significantly increased matrix metalloproteinase-9 plasma levels and significantly decreased plasma levels of tissue inhibitors of metalloproteinases-1 and -4 compared with participants with normal blood pressure. These findings need further investigation.