Circulating biomarkers of collagen metabolism in arterial hypertension: relevance of target organ damage.

OBJECTIVE: Increasing experimental evidence indicates that alterations in the extracellular matrix are implicated in hypertension and its chronic complications. Selected markers of extracellular matrix metabolism were investigated as potential biomarkers for hypertensive remodelling and correlated with the severity and extent of target organ damage (TOD) in patients with essential hypertension. METHODS: We studied 159 consecutive patients being treated for essential hypertension. An exhaustive evaluation of the heart, kidney and blood vessel damage was performed, and plasma levels of plasma procollagen type I (PICP), matrix metalloproteinase-1 (MMP-1) and its inhibitor (tissue inhibitor metalloproteinase-1, TIMP-1) were determined. Patients were categorized into four groups: no TOD (33 patients), level 1 TOD (52 patients), level 2 TOD (44 patients) and level 3 TOD (30 patients). RESULTS: The serum levels of MMP-1 and TIMP-1 were higher in patients with TOD than in hypertensive patients without TOD. Increasing levels of these molecules were progressively associated with an increase in the number of organs damaged, with highest levels of markers in patients with level 3 TOD (heart, kidney and blood vessels). There were no differences in PICP levels between groups. We found a slight but significant correlation between TIMP-1 and all hypertensive organ damage. Logistic regression analysis showed that age, smoking, diabetes mellitus, abdominal perimeter, MMP-1 and TIMP-1 were independently related to the level of TOD. CONCLUSION: Circulating concentration of MMP-1 and TIMP-1 is associated with an extended hypertensive disease, with more TOD. TIMP-1 may have a role as a biomarker of total remodelling burden in hypertensive patients.

Carotid resistive index in treated hypertensive patients: relationship with target organ damage.

AIM: The resistive index (RI) is a hemodynamic parameter that reflects local wall extensibility and related vascular resistance. We analyze the relationship between common carotid RI and target organ damage in treated hypertensive patients. METHODS: We analyzed 265 consecutive hypertensive patients. Risk factors, cardiovascular history and treatments were collected; blood test, urinary albumin excretion (UAE), echocardiography to determine left ventricular mass index (LVMI), ankle-brachial index (ABI) and carotid echo-Doppler ultrasound to calculate the carotid intima-media thickness (IMT) and RI of both common carotids arteries were performed. RESULTS: A positive correlation was found between carotid RI and age, systolic blood pressure, heart rate, carotid IMT, LVMI, UAE and a negative correlation was found with diastolic blood pressure and ABI. Subjects at the top quartile of carotid RI showed a higher prevalence of left ventricular hypertrophy and peripheral artery disease (increased IMT, carotid plaques and lower ABI) compared with those with low RI (p < 0.05). Multiple regression analysis demonstrated that age, systolic and diastolic blood pressure and LVMI independently influence carotid RI. CONCLUSION: Carotid RI is related with age, systolic-diastolic blood pressure and LVMI in hypertensive patient. This evaluation could predict the presence of early cardiovascular damage and provide an accurate estimation of overall risk in this population.

Inflammation and apoptosis in hypertension. Relevance of the extent of target organ damage.

INTRODUCTION AND OBJECTIVES: To investigate the relationship between inflammatory and apoptotic parameters and the severity and extent of target organ damage in patients with essential hypertension. METHODS: We studied 159 consecutive patients with treated essential hypertension. An exhaustive evaluation of damage to heart, kidney, and blood vessels was performed and plasma levels of inflammatory (interleukin 6 and soluble receptor of tumor necrosis factor-alpha type 2) and apoptotic markers (soluble receptor of tumor necrosis factor-alpha type 1 and soluble Fas receptor) were determined. Patients were categorized into four groups: a) no organ damage (33 patients); b) 1 organ damaged (52 patients); c) 2 organs damaged (44 patients), and d) 3 organs damaged (30 patients). RESULTS: Serum levels of interleukin 6, soluble receptor of tumor necrosis factor-alpha type 1 and soluble receptor of tumor necrosis factor-alpha type 2 were higher in patients with target organ damage than in hypertensive patients without organ damage. Increasing levels of these molecules were progressively associated with an increase in the number of organs damaged, and the highest levels were observed in the group with damage to 3 organs (heart, kidney, and blood vessels). There were no differences in soluble Fas receptor levels between groups. Logistic regression analysis showed that age, smoking, diabetes mellitus, abdominal circumference, interleukin 6, and soluble receptor of tumor necrosis factor-alpha type 1 were independently related to the number of target organs damaged. CONCLUSIONS: Extensive hypertensive disease with involvement of more target organs was associated with greater inflammatory and apoptotic activation in these hypertensive patients.