Stella-Maria Kyvelou

Differential impact of metabolic syndrome on arterial stiffness and wave reflections: Focus on distinct definitions

BACKGROUND Arterial stiffness and wave reflections are independent predictors of cardiovascular disease. Metabolic syndrome (MS) is related to increased aortic stiffness in several populations. However, it is unclear whether the association of MS with aortic stiffness differs according to the considered definition. Moreover, data regarding the association of wave reflections with MS are limited. For this purpose, we examined the relationship of arterial stiffness and wave reflections with MS by using four current definitions and a score. METHODS We studied 732 never treated, non-diabetic hypertensive patients. Metabolic syndrome was defined by Adult Treatment Panel III, American Heart Association, World Health Organization (WHO), International Diabetes Federation criteria and MS (GISSI) score. Arterial stiffness was assessed by measuring carotid-femoral pulse wave velocity (PWVc-f). Heart rate-corrected augmentation index (AIx(75)) was estimated as a measure of wave reflections. RESULTS By all definitions, hypertensive patients with MS had higher PWVc-f compared to hypertensives without MS. On the contrary, no significant difference was observed in AIx(75) between patients with and those without MS except when MS was defined by WHO criteria. An independent association emerged between PWVc-f and GISSI score and MS components (p=0.038 and 0.033 respectively) in patients with MS, after adjustment for age, gender, LDL cholesterol and smoking. Nevertheless, after further adjustment for systolic blood pressure or body mass index, the strength of this association was reduced to a non-significant level. CONCLUSION Arterial stiffness is increased in patients with metabolic syndrome irrespective of the definition criteria. On the contrary, metabolic syndrome has no effect on wave reflections, except when this is defined by WHO criteria. Regarding the high prognostic significance of both arterial stiffness and wave reflections, these findings might have important clinical implications.

Nocturnal blood pressure fall and metabolic syndrome score in hypertensive patients.

BackgroundData relating dipping status to metabolic syndrome (MS) scores are not available. The purpose of this study is to investigate any possible association of different dipping patterns to MS scores in untreated patients with essential hypertension. MethodsThe study included 6256 consecutive, treatment-naive patients with essential hypertension who attended our outpatient clinics. All underwent repeated office blood pressure measurements, 24-h ambulatory blood pressure monitoring, and full clinical and laboratory evaluation. The diagnosis of MS was made according to the Adult Treatment Panel III criteria and patients were classified into five groups: group I (hypertension), group II (hypertension+any one component), group III (hypertension+any two components), group IV (hypertension+any three components), and group V (all five components). Dipping pattern was defined as ‘dippers’ with nocturnal systolic blood pressure (NSBP) falling ≥10 but <20%, ‘nondippers’ with NSBP falling ≥0% but <10%, ‘extreme dippers’ with NSBP falling ≥20%, and ‘reverse dippers’ with NSBP increasing. ResultsHypertensive patients with MS (n=2573) had higher clinical and ambulatory blood pressure values (P<0.001), whereas the dominant dipping pattern in the non-MS group was nondippers (47.6%), and in the MS group, extreme dippers (37.8%). Furthermore, a considerable decrease in the prevalence of dippers was noticed with the increasing number of MS components (21.1 vs. 19.2 vs. 14.5 vs. 8.4 vs. 7.2%, P<0.001). In contrast, a significant rise in the prevalence of reverse dippers was observed with the increasing number of MS components (7.4 vs. 10.1 vs. 14.9 vs. 20.4 vs. 31.2%, P<0.001). ConclusionsIt seems that hypertensive patients have an increased prevalence of abnormal dipping patterns as the number of MS components rises.

Beneficial Effect of Angiotensin II Type 1 Receptor Blocker Antihypertensive Treatment on Arterial Stiffness: The Role of Smoking

The purpose of the present study was to assess angiotensin receptor blocker (ARB) treatment on arterial stiffness in select hypertensive patients and define possible differences between smokers and nonsmokers. The authors evaluated 81 consecutive, nondiabetic patients (mean age, 52 years; 47 men) with uncomplicated essential hypertension with high plasma renin activity who were administered monotherapy with irbesartan, an ARB, at maximal dose. Patients were divided into smokers (n=24) and nonsmokers (n=57). Carotid‐radial pulse wave velocity (PWVc‐r), carotid‐femoral pulse wave velocity (PWVc‐f), and augmentation index (AIx) were measured before and 6 months after ARB antihypertensive treatment. All mean values of elastic effect indices were decreased after irbesartan monotherapy (AIx, from 26.3%to 21.2% [P<.01]; PWVc‐f, from 7.7 m/s to 7.3 m/s [P<.05], and PWVc‐r, from 8.9 m/s to 8.3 m/s [P<.001]). When comparing smokers vs nonsmokers, no difference was noted in AIx and PWVc‐f change (P=not significant), while PWVc‐r change was greater in smokers compared with nonsmokers (P<.05). Chronic ARB treatment may favorably affect arterial stiffness and wave reflections in hypertensive chronic smokers with elevated plasma renin levels.

Nocturnal blood pressure fall and metabolic syndrome score in patients with white coat hypertension.

BackgroundAccumulating data report that white coat hypertension (WCH) is associated with target organ damage. Metabolic syndrome (MS), and nondipping pattern is also associated with increased cardiovascular risk. The purpose of this study was to explore the nocturnal blood pressure fall in WCH patients according to their MS score. MethodsThe study comprised 2300 patients with WCH who attended our outpatient clinics. All underwent repeated office blood pressure measurements, 24-h ambulatory blood pressure monitoring, full clinical and laboratory evaluation. The diagnosis of MS was made according to the Adult Treatment Panel III criteria and patients were classified into five groups: group I (hypertension), group II (hypertension and any one component), group III (hypertension and any two components), group IV (hypertension and any three components), and group V (all five components). Dipping pattern was defined as ‘dippers’ with nocturnal systolic blood pressure (NSBP) fall greater than or equal to 10% but less than 20%, ‘nondippers’ with NSBP fall greater than or equal to 0% but less than 10%, ‘extreme dippers’ with NSBP fall greater than or equal to 20%, and ‘reverse dippers’ with NSBP increase. ResultsPatients were divided into two groups according to the presence (n=522) and absence (n=1778) of MS. The overall prevalence of MS in the study population was 22.7%. Comparing the non-MS group with the MS we observed significant differences for nondippers (24.5% vs. 38.9%, P<0.001), dippers (54.4% vs. 43.5%, P<0.001), extreme dippers (17.8% vs. 11.3%, P<0.001), and reverse dippers (3.3% vs. 6.3%, P=0.007). ConclusionPatients with WCH and increased number of MS components present with elevated nighttime SBP levels. This observation is of a great significance in the assessment of the cardiovascular risk in these patients.

Urine Albumin Excretion, Within Normal Range, Reflects Increasing Prevalence of Metabolic Syndrome in Patients With Essential Hypertension

J Clin Hypertens(Greenwich). 2010;12:597–602.

Early adverse effect of abnormal glucose metabolism on arterial stiffness in drug naive hypertensive patients.

Arterial stiffness is independently related to increased cardiovascular risk in the hypertensive population. The aim of the present study was to investigate whether various stages of abnormal glucose metabolism may differently affect arterial stiffness in hypertensive patients and whether there is any difference in arterial stiffness among patients with normal glucose regulation. We studied 1375 never-treated hypertensive subjects. Participants were divided into four metabolic groups: normal glucose regulation (NG), impaired fasting glucose, impaired glucose tolerance and type-2 diabetes mellitus (DM 2). Hypertensive subjects with NG were subdivided into three groups according to glucose levels. Arterial stiffness was estimated by carotid-femoral pulse wave velocity (PWV). PWV showed a significant increase from patients with NG to DM 2 (from 7.74±1.38 to 8.40±1.30 to 8.86±1.30 to 10.09±2.07 m/s respectively, p<0.001). Among hypertensive subjects with NG there was an increase in PWV from low normal to high normal values of glucose (p<0.01). PWV was independently related to all glucose metabolic parameters (p<0.001 for all). In the present study, we demonstrated an association between arterial stiffness and glucose tolerance in hypertensive subjects. Given the prognostic significance of arterial stiffness, aims should be towards closer monitoring and intensive care of hypertensive patients with abnormal glucose metabolism.

Beneficial effects of angiotensin II type 1 receptor blocker antihypertensive treatment on inflammation indices: the effect of smoking.

The effect of long‐term angiotensin II type 1 receptor blocker (ARB) therapy on inflammation indices has not been fully investigated in a hypertensive population. The authors evaluated 323 consecutive nondiabetic patients (mean age, 57 years; 176 men; 92 smokers) with high renin activity and uncomplicated essential hypertension whose blood pressure levels normalized (from 163.9/100.7 mm Hg to 131.6/82.8 mm Hg) after 4 weeks of ARB or ARB/diuretic treatment. All patients underwent full laboratory evaluation (routine examination of blood and urine, liver, kidney, thyroid function, and lipid and glucose profiles), including measurement of high‐sensitivity C‐reactive protein and serum amyloid A levels, at drug‐free baseline, which was repeated after 6 months of ARB or ARB/diuretic treatment. A significant (P<.001) overall decrease was noted in both high‐sensitivity C‐reactive protein (−0.41±1.56 mg/dL) and serum amyloid A (−0.62±2.03 mg/dL), but a smaller decrease in high‐sensitivity C‐reactive protein and serum amyloid A change was seen in the smoker subgroup compared with nonsmokers (P<.05), indicating that the ARB or ARB/diuretic anti‐inflammatory effect may be adversely affected by smoking status.

Relationships of osteoprotegerin with albuminuria and asymmetric dimethylarginine in essential hypertension: integrating vascular dysfunction

Objectives: To investigate the inter-relationships of osteoprotegerin (OPG) with albumin to creatinine ratio (ACR) and asymmetric dimethylargine (ADMA) in hypertensive patients. Methods: In 198 untreated non-diabetic hypertensive patients [130 males, mean age = 51.5 years, office blood pressure (BP) = 152/98 mmHg] ACR values and OPG and ADMA levels were determined. Results: Based on the median value of OPG distribution (5.03 pmol/l) patients with high (n = 101) compared with those with low OPG values (n = 97) had greater 24-h systolic BP (152 ± 5 versus 137 ± 7 mmHg, p < 0.0001), ACR [25.3 (5 – 190) versus 17.3 (5 – 92) mg/g, p = 0.003) and ADMA [0.62 (0.58 – 0.68) versus 0.57 (0.48 – 0.62) μmol/l, p = 0.001), independently of confounding factors. Multiple regression analyses revealed that ADMA (b = 0.388, p < 0.0001), 24-h systolic BP (b = 0.228, p = 0.01) and ACR (b = 0.470, p < 0.0001) were independent predictors of OPG (R2 = 0.398, p < 0.0001). Conclusions: In hypertensive patients, high OPG levels are accompanied by pronounced albuminuria and endothelial dysfunction, as reflected by raised ADMA levels. Furthermore, the independent associations of OPG with ACR and ADMA, suggests a link between OPG and the progression of diffuse hypertensive vascular damage.

AMBULATORY BLOOD PRESSURE PROFILE IN HYPERTENSIVE PATIENTS WITH Â-THALASSEMIA MINOR: PP.14.05

Objective: â-thalassemia trait (â-TT) is a genetic blood disorder, more common in Mediterranean countries, including Greece. Previous studies have indicated a protective effect of â-TT on myocardial infarction due to lower cholesterol or lower blood pressure levels. However, the ambulatory blood pressure profile of such patients has not been investigated yet. Moreover, it has been reported that anemic hypertensive patients usually have significantly elevated nocturnal BP, and decreased mean 24-h BP and daytime BP. Thus, the purpose of the present study was to investigate the ABPM profile of hypertensives with â-TT, in comparison to all cause anemic and non-anemic essential hypertensive patients. Design and Methods: The study comprised 8861 essential hypertensive, non-diabetic patients who were divided in three groups: groups I (n = 191, with â-TT), group II (n = 655, anemic), and group III (n = 8015, non-anemic). All patients underwent full laboratory workout and were subjected to ABPM. Anemia was defined as hemoglobin < 12 g/dl for women and < 13 g/dl for men, while patients with â-TT were self-referred. Results: The distribution of dipping pattern among the three groups was (61.3 vs 41.2 vs 45.8 %, p < 0.001), while for non-dipping (20.4 vs 31.5 vs 27.7 %, p < 0.001), for extreme-dipping (15.7 vs 15.0 vs 17.5%, p < 0.001) and for reverse dipping (2.6 vs 12.4 vs 9.0%, p < 0.001). Furthermore, mean daytime-SBP among the three groups was (140 ± 7 vs 142 ± 11 vs 141 ± 9 mmHg, p = 0.03) and mean nighttime SBP (125 ± 10 vs 131 ± 15 vs 129 ± 13 mmHg, p < 0.001). In multiple regression analysis after adjustments for age, body mass index and lipid levels, the differences among daytime and nighttime SBP remained significant [(140 ± 9 vs 142 ± 9 vs 141 ± 9 mmHg, p = 0.04), (125 ± 13 vs 131 ± 13 vs 129 ± 13 mmHg, p < 0.001), respectively]. Conclusions: Hypertensive patients with â-TT present with a better 24-h BP profile in comparison with anemic and non-anemic hypertensives. Thus â-TT may act protectively in their total cardiovascular risk profile.

NIGHT-TIME HYPERTENSION AND TARGET ORGAN DAMAGE IN NEVER TREATED PATIENTS: PP.3.111

Objective: Essential hypertensive patients with non-dipping blood pressure profile are at higher risk of cardiac and all-cause mortality. Several studies involving subjects with uncomplicated essential hypertension have revealed an association between a non-dipper BP profile and an increased risk of target organ damage (TOD). The purpose of the present study was to assess possible differences in TOD status of patients presenting with isolated nocturnal hypertension (INO), isolated daytime hypertension (IDH) and day-night hypertension (DNH). Design and Methods: The study comprised 1045 essential, non-diabetic, hypertensive patients who refereed to our outpatient clinic for BP management. Patients underwent full clinical, anthropometric, laboratory and echocardiographic evaluation, while BP was assessed by a 24 h ambulatory blood pressure monitoring (ABPM). Furthermore, in all patients the levels of C-reactive protein (hsCRP) were measured and arterial stiffness was assessed by pulse wave velocity (PWV) using the Complior device. Finally, all patients underwent a 24-h urine collection and microalbumin levels were measured. Results: Based on ABPM results patients were divided in three groups: group I, INO, (n = 192), group II IDH (n = 109) and group III DNH (n = 744). Microalbumin(>20 mg/dl) and LV mass index were mostly present in patients with DNH in comparison to patients with IDH and INO [(30.3 vs 22.9 vs 18.7%, p = 0.003), (37.3 vs 15.6 vs 16.6%, p < 0.001). PWV (>8m/s) and CRP (>1.2 mg/L) were higher in DNH than in IDH and INO [(42.7 vs 33.9 vs 23.4%, p < 0.001), (46.6 vs 42.2 vs 33.8%, p = 0.006). In multivariate analysis, patients with INO in comparison to DNH had lower possibility to present with high microalbuminuria [OR = 0.58, p = 0.009, 95%CI], LV hypertrophy [OR = 0.30, p < 0.0001, 95% CI], elevated hsCRP [OR = 0.66, p = 0.018, 95%CI], and high PWV [OR = 0.52, p = 0.001, 95%CI]. Conclusions: The present study points to the burden posed by day-night BP in TOD in essential hypertensive patients, which is clearly higher than that of isolated nocturnal and daytime hypertension.