Endothelial dysfunction in patients with white coat hypertension

The GG genotype of the -152 G/A vascular endothelial growth factor (VEGF) polymorphism predisposes to hypertension-related chronic kidney disease

Our purpose was to determine whether the VEGF -152 G/A polymorphism could be associated with chronic kidney disease and endothelial dysfunction in hypertensive patients. There were 100 healthy volunteers enrolled into the control group. The group of patients was constituted by 99 consecutively admitted hypertensive patients referred to our Institution by their general practitioner. All patients were treated with anti-hypertensive polytherapy. Presented study revealed that the hypertensive patients bearing the GG genotype were characterized by the highest values of diastolic blood pressure and markers of endothelial damage such as Angiogenin, Endostatin, CRP as well as von Willebrandt factor. In addition, higher number of immature endothelial progenitor cells with CD34(+)CD133(+), CD34(+)CD133(-) markers was observed in GG hypertensive carriers while in normotensive individuals no differences were found. Such phenomenon may indicate an increased mobilization of bone-marrow derived endothelial progenitors. It may testify to the preserved compensatory mechanism in chronic kidney disease (CKD) patients until the G3a stage of the disease. Moreover, patients with higher estimated glomerular filtration rate (eGFR) level had lower of vWf and Endostatin values, and higher level of VEGF. Taken together our findings clearly indicate the -152 GG hypertensive carriers as more prone to develop CKD. We can suspect that the VEGF -152 GG genotype is strongly associated with hypertension-dependent CKD.

Mechanical and circulating biomarkers in isolated clinic hypertension

1. This review examines the current evidence for altered mechanical and circulating biomarkers in isolated clinic hypertension and their potential significance. 2. Arterial stiffness, as assessed by central pulse wave velocity, is influenced by multiple cardiovascular risk factors; however, an independent association with isolated clinic hypertension (ICHT) has not been convincingly shown in four small studies. 3. Endothelial dysfunction, as assessed by brachial artery flow-mediated vasodilation, circulating levels of endothelial markers (e.g. nitrite/nitrate, von Willebrand factor, endothelin-1) and/or circulating levels of inhibitors of vascular nitric oxide (plasma asymmetric dimethylarginine, homocysteine), has been shown to be present in established hypertension and to a variable and inconsistent extent in subjects with ICHT. 4. Evidence of increased oxidative stress in ICHT versus normotensive subjects was found in two of three studies. 5. Circulating inflammatory markers C-reactive protein and plasminogen activator inhibitor-1 were significantly increased in two of three and two of two studies, respectively, in ICHT compared with normotensive subjects. 6. Urinary albumin excretion is a marker of both arterial and renal disease. The consensus from seven studies in patients with ICHT is that albuminuria is not an independent marker for ICHT. 7. Studies to date assessing biomarkers in ICHT have been small and cross-sectional. Larger, long-term longitudinal studies of arterial functional and circulating biomarkers are required to assess the potential vascular impact of ICHT.

White-coat hypertension: a clinical review

White-coat hypertension (WCHT), also called 'isolated office or clinic hypertension', is defined as the occurrence of blood pressure (BP) values higher than normal when measured in the medical environment, but within the normal range during daily life, usually defined as average daytime ambulatory BP (ABP) or home BP values (<135 mm Hg systolic and <85 mm Hg diastolic). The prevalence of WCHT varies from 15% to over 50% of all patients with mildly elevated office BP (OBP) values. In untreated hypertensive patients, the probability of WCHT especially increases with female gender and a mildly elevated OBP level. The value of other possible determinants such as (non) smoking status, duration of hypertension, left ventricular mass, number of OBP measurements, educational level, etc. is less consistently shown. Although, for various reasons, studies evaluating the long-term effects of WCHT are not always easy to interpret, most data indicate that persons with WCHT have a worse or equal cardiovascular prognosis than normotensives, but a better one than those with sustained hypertension. WCHT is sometimes considered a prehypertensive state, but data on the long-term evolution of subjects with WCHT are scarce. Patients with WCHT and a high cardiovascular risk or proven target organ damage should be pharmacologically treated. Subjects with uncomplicated WCHT should probably not receive medical therapy, but a close follow-up, including regular assessment of other risk factors and measurement of OBP (every 6 months) and ABP (every 1 or 2 years), is warranted.