Assessment of target-organ damage in adolescent white-coat and sustained hypertensives.

AIMS AND SCOPE: The aim of the present study was to assess whether a difference exists between intima-media thickness and the left ventricular mass index in healthy nonhypertensive, white-coat hypertensive and sustained hypertensive adolescents. PATIENTS AND METHODS: Fifty-nine normotensive and 120 hypertensive adolescents were enrolled in our study. Hypertensive patients were classified into white-coat hypertension (WCH) and sustained hypertension groups based on 24-h ambulatory blood pressure measurements. Both normotensive and hypertensive individuals underwent routine laboratory tests, intima-media thickness measurements on the common carotid arteries and transthoracic echocardiography to measure the left ventricular mass index (LVMI). RESULTS: Intima-media thickness was higher both in WCH and sustained hypertension compared with healthy normotensive individuals (controls: 0.048 ± 0.01 cm, WCH: 0.056 ± 0.01 cm, sustained hypertension: 0.054 ± 0.012 cm, both P < 0.001 compared with controls, nonsignificant difference between the two hypertensive groups). There was no difference between the LVMI of control individuals and WCH (LVMI: 35.5 ± 10.3 g/m and 37.7 ± 11.2 g/m respectively, P = 0.87). LVMI in sustained hypertension group (LVMI: 44.1 ± 14.1 g/m) was significantly higher both compared with WCH (P < 0.05), and healthy adolescents (P < 0.001). CONCLUSION: Target-organ damage develops in a stepwise fashion in adolescent hypertension. An increased intima-media thickness can be demonstrated not only in the sustained but also in the white-coat form of adolescent hypertension.

Gender-related differences in adolescent hypertension and in target organ effects.

AIMS: To assess whether a gender difference exists in adolescent hypertension and its target organ damage and to compare potential confounding factors and target organ damage in hypertensive and normotensive adolescent girls. METHODS: From the Debrecen Hypertension Study, the anthropometric, blood pressure, and laboratory data as well as intima-media thickness (IMT) and left ventricular mass index (LVMI) of 58 hypertensive boys, 56 hypertensive girls, and 30 normotensive girls were analyzed. RESULTS: Both systolic and mean blood pressure values were higher in adolescent hypertensive boys than in girls. This difference was also present when comparing 24-hour average blood pressure values. Plasma concentrations of nitric oxide (NO) and endothelin-1 were not different in the two gender groups. IMT of the carotid arteries were similar in hypertensive boys and girls, but a significantly higher LVMI was detected in boys. A significant difference was detected in anthropometric data (height, weight, and body mass index [BMI]), plasma concentration of NO (lower levels in hypertensives), and IMT in hypertensive and normotensive girls (higher IMT in hypertensive girls). CONCLUSIONS: There is a difference between the severity of hypertension between hypertensive adolescent girls and boys. Hypertensive girls differ from normotensive girls not only in blood pressure values but also in risk factors and subclinical target organ effects. Further studies are needed to explain the gender differences in adolescent hypertension. The potential role of sex hormones in hypertensive teenagers also needs to be clarified in future works.

[Importance of ambulatory blood pressure monitoring in adolescent hypertension]. / Az ambuláns vérnyomás-monitorozás jelentôsége serdülôkorban.

The prevalence of adolescent hypertension is increasing. The national epidemiological study found 2.5% prevalence, while it is 4.5% according to the newest international survey. Repeated casual blood pressure measurements, but not ambulatory blood pressure monitoring is needed for the diagnosis of adolescent hypertension on the basis of the presently available European guideline. At the last decade growing evidence came into light for ambulatory blood pressure monitoring in adolescence. These data show better correlation with end-organ damages than casual measurements. In patients with hypertension diagnosed based on repeated casual blood pressure measurements, 24-hour monitoring showed normal blood pressure in 21-47%, so this is the rate of white coat hypertension. Masked hypertension can also be diagnosed with the help of this method, which has a prevalence of 7-11%. We can also get useful data for secondary forms of hypertension. Until the appearance of the new European guidelines, more frequent use of ambulatory blood pressure monitoring is affordable. The confirmation of the diagnosis based on elevated casual blood pressure data is important. Ambulatory blood pressure monitoring is suggested in cases suspicious for white coat or masked hypertension, in cases of target organ damages or therapy resistant hypertension. Before administration of pharmaceutical therapy in adolescence hypertension - according to author's opinion - ambulatory blood pressure monitoring is absolutely necessary.

Associations of adiponectin with paraoxonase 1 and sE-selectin in hemodialyzed patients.

BACKGROUND/AIMS: In hemodialyzed (HD) patients, adiponectin and sE-selectin levels are elevated, while antioxidant paraoxonase 1 activity (PON1) is decreased. We determined if the hyperadiponectinemia in HD patients has a protective effect on the decrease in PON1 and elevation in sE-selectin in kidney failure. METHODS AND DESIGN: Predialysis serum adiponectin, PON1 and sE-selectin as well as other metabolic variables were measured in 70 HD patients. RESULTS: Adiponectin had (1) no association with PON1 or sE-selectin, (2) a positive association with dialysis efficiency and HDL-C, and (3) an inverse association with BMI, waist circumference, HOMA IR, triglyceride, hsCRP, fibrinogen, and albumin. Moreover, albumin, BMI, and HOMA-IR were independent negative predictors of adiponectin. CONCLUSIONS: In kidney failure, in contrast to normal renal function, higher adiponectin levels had no correlation with PON1 activity or the sE-selectin level. However, adiponectin has an association with dialysis efficiency and, similar to individuals with preserved kidney function, traits of metabolic syndrome. In addition to BMI and HOMA-IR, the serum albumin concentration is also one of the independent negative predictors of the serum adiponectin level. Collectively, these findings may add details to the understanding of the role that adiponectin plays in chronic renal disease related to 'reverse epidemiology'.

[The role and clinical importance of nitric oxide-endothelin system in hypertension]. / A nitrogén-oxid-endotelin rendszer szerepe és klinikai jelentosége hypertoniában.

This review summarises the role of the endothelium in the regulation of the vascular tone, emphasizes the importance of nitric oxide and endothelin at the vasodilator and vasoconstrictor physiological processes. Mainly, the nitric oxide is responsible for the basal tone of the vasculature, but plenty of modifying factors (endothelin, angiotensin-II, prostacyclin) have also important effects. Endothelial dysfunction observable in hypertension, which characterised by disorder of the endothelium-dependent relaxation, and predominance of the vasoconstrictor processes. Disorder of synthesis, decreased biological activity and increased degradation of the nitric oxide could play a role in the fall of the basal vasodilator tone, as well as other factors influencing the production of nitric oxide. Due to a relaxation disorder, the vasoconstrictor endothelin come to the front, following morphological changes of the vessels, afterwards. Endothelial dysfunction of the medium size arteries lead to thickening of the intima, what can follow by non-invasive measurements at the common carotid arteries. It is unambiguous in hypertensive patients that augmenting the tone of the resistance vessels, the peripheral vascular tone increases. It is proved in hypertensive adults that damaged function of the cerebral arterioles results in decrease of the vasoreactivity following a hypo- or hypercapnic stimuli. The imbalance of the nitric oxide-endothelin system is not only a process what helps to partly explain the pathophysiology of hypertension, but also a therapeutic aim preventing the process of atherosclerosis.

[Prevention of target organ damage with modern antihypertensive agents]. / Komplex célszerv-védelem korszeru vérnyomáscsökkentokkel.

This review summarises the recent epidemiological data on hypertension, the aims of the treatment of hypertension, and emphasizes the importance of the modification of target organ damages and accelerated clinical conditions. Because the pathogenesis of hypertension is extremely complex, the therapy most likely requires a combined drug administration. The modern third generation dihydropyridine calcium channel blocker, amlodipine, not only has a favourable antihypertensive and anti-ischemic effect, but anti-atherosclerosis properties as well. There are plenty of evidence which demonstrate that lisinopril, a first line antihypertensive agent, has a positive effect in the treatment of left ventricular hypertrophy, retinopathy and nephropathy, and also has a favourable outcome after myocardial infarction and in heart failure. The combined administration of the two drugs leads to a favourable additive effect, with a decrease in the number and severity of side effects. The results of the ASCOT study proved a favourable effect with amlodipine based, combination therapy with an ACE-inhibitor, compared with the traditional beta-blockers and diuretics. The data of the CAFE sub-study showed, that in spite of the similar peripheral antihypertensive effect, the amlodipine based therapy decreased the central aortic pulse pressure to a greater extent. The central aortic pressure showed a good correlation with the end-points of the study, respectively. The results of the Hungarian multicenter study (HAMLET) proved the effective and safe administration of the two drugs in combination. Based on the above evidence, the fixed-dose combination of the CCB-ACE inhibitor (amlodipine-lisinopril) has not only effective blood pressure reducing properties, but also results in cardiovascular risk reduction, good tolerability and favourable compliance.

Both nitric oxide and endothelin-1 influence cerebral blood flow velocity at rest and after hyper- and hypocapnic stimuli in hypertensive and healthy adolescents.

BACKGROUND AND PURPOSE: Nitric oxide (NO)/endothelin imbalance may play a role in the regulation of cerebral blood flow. The aim of the present study was to assess whether these endothelial factors influence middle cerebral artery blood flow velocities (MCAV) and cerebrovascular reactivity (CVR) in healthy and hypertensive adolescents. SUBJECTS AND METHODS: 106 adolescents (61 hypertensive and 45 normotensive) underwent transcranial Doppler measurements of the middle cerebral artery at rest and after 30 s of breath-holding (BH) and 60 s of hyperventilation (HV). Additionally, NO and endothelin-1 (ET-1) concentrations of the serum were assessed. The correlation between NO and ET-1 levels as well as MCAV and CVR values was analyzed. RESULTS: Resting MCAVs were higher among hypertensive teenagers (76.5 +/- 24 vs. 62.8 +/- 15.6 cm/s, respectively, p < 0.001). CVR values did not differ between hypertensive and healthy adolescents after the BH and HV procedure. A significant negative correlation was found between absolute MCAV values and NO concentrations. ET-1 was positively related to MCAV. CONCLUSIONS: Cerebral blood flow velocities, but not CVR values, are associated with serum NO and ET-1 concentrations in adolescents.

Dietary self-efficacy: determinant of compliance behaviours and biochemical outcomes in haemodialysis patients.

BACKGROUND: Despite the diversity of proposed theories, researchers are still unable to fully explain dietary compliance behaviours of dialysis patients. Dietary self-efficacy, a concept less studied in dialysis, has been linked to positive compliance outcomes in the chronic illness literature. Therefore, the aim of the present research was to determine how dietary self-efficacy is related to selected biochemical markers and self-reported behavioural outcomes in haemodialysis patients. METHODS: 107 subjects participated in a cross-sectional study. Four questionnaires assessed dietary self-efficacy, compliance attitudes and behaviours, and staff-patient relationships. Laboratory outcomes were retrospectively obtained from patients' medical records and averaged for the previous 6 months. RESULTS: Of the behavioural measures, only dietary self-efficacy was associated with laboratory outcomes. Dietary self-efficacy was also positively related to staff-patient relationships and to patients' self-reported assessment of compliance behaviours. Women had greater dietary self-efficacy than men. The number of family members living with the respondent was inversely related to dietary self-efficacy. CONCLUSIONS: Results indicated that dietary self-efficacy determined both behaviours and laboratory outcomes. Patients with greater dietary self-efficacy had lower serum potassium and weight gain, showed favourable compliance attitudes and behaviours toward prescribed regimens and fostered better relationships with staff. Based on these findings we recommend an experimental approach to clarify whether maximizing dietary self-efficacy efforts is without psychological burden to patients and whether the positive effect of increased dietary self-efficacy is maintained in long-term dialysis patients.