Microalbuminuria in 411 untreated individuals with established hypertension, white coat hypertension, and normotension

Target Blood Pressure Values in Ambulatory Blood Pressure Monitoring

INTRODUCTION

2018 ESC/ESH guidelines have recommended 24-h ambulatory blood pressure monitoring to assess hypotensive therapy in many circumstances. Recommended target blood pressure in office blood pressure measurements is between 120/70 and 130/80 mmHg. Such targets for 24-h ambulatory blood pressure monitoring lacks.

AIM

We aimed to define target values of blood pressure in 24-h ambulatory blood pressure monitoring in hypertensive patients.

METHODS

Office blood pressure measurements and 24-h ambulatory blood pressure monitoring data were collected from 1313 hypertensive patients and sorted following increasing systolic (SBP)/diastolic (DBP) blood pressure in office blood pressure measurements. The corresponding 24-h ambulatory blood pressure monitoring to office blood pressure measurements values were calculated.

RESULTS

Values 130/80 mmHg in office blood pressure measurements correspond in 24-h ambulatory blood pressure monitoring: night-time SBP/DBP mean: 113.74/66.95 mmHg; daytime SBP/DBP mean: 135.02/81.78 mmHg and 24-h SBP/DBP mean: 130.24/78.73 mmHg. Values 120/70 mmHg in office blood pressure measurements correspond in 24-h ambulatory blood pressure monitoring: night-time SBP/DBP mean: 109.50/63.43 mmHg; daytime SBP/DBP mean: 131.01/78.47 mmHg and 24-h SBP/DBP mean: 126.36/75.31 mmHg.

CONCLUSIONS

The proposed blood pressure target values in 24-h ambulatory blood pressure monitoring complement the therapeutic target indicated in the ESC/ESH recommendations and improves 24-h ambulatory blood pressure monitoring usefulness in clinical practice.

White-Coat Hypertension: Pathophysiological and Clinical Aspects: Excellence Award for Hypertension Research 2020

Few issues of modern cardiovascular medicine have been as controversial as the relationship between white-coat hypertension (WCH), that is, a common condition in which office blood pressure is elevated while out-of-office blood pressure (ambulatory blood pressure or home blood pressure) is normal. While earlier studies showed no increased risk of cardiovascular events in WCH compared with the normotensive state, more recent studies have changed this conclusion by showing that an increased cardiovascular risk represents a trait of this hypertensive phenotype. The present article will review a number of issues related to WCH, that is, its definition, pathophysiological background, clinical alterations, and prognostic significance. This will be done by considering the available evidence published during the last decades, with special focus on the data collected in PAMELA (Pressioni Arteriose Monitorate e Loro Associazioni)-a research project performed with a cross-sectional and longitudinal design, which has provided a series of novel clinical information on WCH throughout the years. The final part of the article will discuss the therapeutic implications of the abovementioned evidence, as well as some controversial or still undefined issues related to WCH, whose investigation will be an important goal to pursue by future research.

Microalbuminuria and cardiorenal risk: old and new evidence in different populations

Since the association of microalbuminuria (MAU) with cardiovascular (CV) risk was described, a huge number of reports have emerged. MAU is a specific integrated marker of CV risk and targets organ damage in patients with hypertension, chronic kidney disease (CKD), and diabetes and its recognition is important for identifying patients at a high or very high global CV risk. The gold standard for diagnosis is albumin measured in 24-hour urine collection (normal values of less than 30 mg/day, MAU of 30 to 300 mg/day, macroalbuminuria of more than 300 mg/day) or, more practically, the determination of urinary albumin-to-creatinine ratio in a urine morning sample (30 to 300 mg/g). MAU screening is mandatory in individuals at risk of developing or presenting elevated global CV risk. Evidence has shown that intensive treatment could turn MAU into normoalbuminuria. Intensive treatment with the administration of an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker, in combination with other anti-hypertensive drugs and drugs covering other aspects of CV risk, such as mineralocorticoid receptor antagonists, new anti-diabetic drugs, and statins, can diminish the risk accompanying albuminuria in hypertensive patients with or without CKD and diabetes.

White coat syndrome and its variations: differences and clinical impact

Hypertension is closely linked to increased cardiovascular risk and development of target organ damage (TOD). Therefore, proper clinical follow-up and treatment of hypertensive subjects are mandatory. A great number of individuals present a variation on blood pressure (BP) levels when they are assessed either in the office or in the out-of-office settings. This phenomenon is defined as white coat syndrome - a change in BP levels due to the presence of a physician or other health professional. In this context, the term "white coat syndrome" may refer to three important and different clinical conditions: 1) white coat hypertension, 2) white coat effect, and 3) masked hypertension. The development of TOD and the increased cardiovascular risk play different roles in these specific subgroups of white coat syndrome. Correct diagnose and clinical guidance are essential to improve the prognosis of these patients. The aim of this review was to elucidate contemporary aspects of these types of white coat syndrome on general and hypertensive population.

Impact of age on the association between 24-h ambulatory blood pressure measurements and target organ damage

OBJECTIVE

The aim of this study was to evaluate the impact of age on the associations between hemodynamic components derived from 24-h ambulatory blood pressure (24-h ABPM) and target organ damage, in apparently healthy, nonmedicated individuals.

METHODS

Twenty-four-hour ABPM and target organ damage (left ventricular mass index, pulse wave velocity, urine albumin : creatinine ratio and carotid atherosclerotic plaques) were evaluated in 1408 individuals. Associations were examined in regression models, stratified for age [middle-aged (41 or 51 years) or elderly (61 or 71 years)], and adjusted for sex, smoking status, and total-cholesterol.

RESULTS

In middle-aged individuals, an increase of 10 mmHg in 24-h SBP was independently associated with an increase of 3.8 (2.7-4.8) g/m in LVMI. The effect was nearly doubled in the elderly subgroup, where the same increase resulted in an increase in LVMI of 6.3 (5.0-7.6) g/m (P for interaction <0.01). An increase of 10 mmHg of 24-h SBP was associated with a 6.7% increase in pulse wave velocity in middle-aged individuals and with an 9.1% increase in elderly individuals (P for interaction <0.01). An independent association between 24-h ABPM and urine albumin : creatinine ratio was only observed in the elderly subgroup. Associations between the presence of atherosclerotic plaques and components from 24-h ABPM except 24-h DBP were not modified by age (all P for interaction >0.26).

CONCLUSION

Age enhances the associations between hemodynamic components obtained from 24-h ABPM and measures of arterial stiffness, microvascular damage, and cardiac structure, but not atherosclerosis.

White-coat and masked hypertension are associated with albuminuria in a general population: the Hisayama Study

Epidemiological and clinical studies have investigated the influence of hypertension on chronic kidney disease (CKD), but limited data are available for the associations of white-coat hypertension (WCHT), masked hypertension (MHT) and sustained hypertension (SHT) with kidney dysfunction in general populations. We examined the associations of these types of hypertension with CKD (albuminuria and reduction in estimated glomerular filtration rate (eGFR)) in a cross-sectional survey of 2974 community-dwelling Japanese aged ⩾40 years. The types of hypertension were defined based on combined measurements of clinic and home blood pressures. Albuminuria was determined as urinary albumin-creatinine ratio (UACR) levels ⩾30.0 mg g^-1. The eGFR was calculated using the Japanese equation. The age- and sex-adjusted geometric mean of the UACR values was significantly higher in the subjects with WCHT (20.2 mg g^-1), MHT (19.6 mg g^-1) and SHT (31.6 mg g^-1) than in those with normotension (NT) (12.5 mg g^-1) (all P<0.001). Compared with NT, all types of hypertension were significantly associated with an increased likelihood of albuminuria (the age- and sex-adjusted prevalence of albuminuria; NT 14.1%, WCHT 26.3%, MHT 26.4% and SHT 43.3%; all P<0.001). These associations remained significant even after adjustment for other risk factors. However, the age- and sex-adjusted mean of eGFR and the prevalence of low eGFR (<60 ml min^-1 per 1.73 m²) did not differ between NT and the three hypertension types. The associations of the types of hypertension with the likelihood of CKD were similar to those for albuminuria. Our findings suggest that WCHT, MHT and SHT are associated with albuminuria in the general Japanese population.

Prevalence of microalbuminuria and its associated cardiometabolic risk factors in Korean youth: Data from the Korea National Health and Nutrition Examination Survey

Background

Microalbuminuria is a known early predictive factor for renal and cardiovascular diseases, not only for patients with diabetes mellitus or hypertension but also in the general population. However, the prevalence and risk factors associated with microalbuminuria in Korean youth are unknown.

Objectives

The aims of this study are to evaluate the prevalence of microalbuminuria and the association between microalbuminuria and obesity or cardiometabolic risk factors in Korean children and adolescents without diabetes.

Methods

This study examines data obtained from the Korea National Health and Nutrition Examination Survey (between 2011 and 2014). It includes a total of 1,976 participants aged between 10 and 19 years (boys 1,128 and girls 848). Microalbuminuria was defined as a urine albumin-to-creatinine ratio (UACR) of ≥ 30 mg/g and < 300 mg/g. Association between microalbuminuria and the risk factors for cardiometabolic diseases including insulin resistance was evaluated.

Results

The prevalence of microalbuminuria was found to be 3.0% in Korean children and adolescents over this time period. The mean UACR for non-obese youth was significantly greater than that found in obese youth (3.2 ± 0.1 mg/g in the non-obese group vs. 2.1 ± 0.2 mg/g in the obese group; P < 0.001). In multiple logistic regression analysis, microalbuminuria was associated with hyperglycemia (OR 2.62, 95% CI 1.09–6.30) and hemoglobin A1c (OR 3.34, 95% CI 1.09–10.17) in the non-obese group and hypertension (OR 14.10, 95% CI 1.12–177.98) and HbA1c (OR 6.68, 95% CI 1.87–23.95) in the obese group.

Conclusions

The prevalence of microalbuminuria is not prominent in obese children and adolescents. Our findings demonstrated that the presence of hypertension and hyperglycemia was associated with microalbuminuria. Especially Hemoglobin A1c was associated with microalbuminuria in youths regardless of weight status. Microalbuminuria in pediatric population can be a helpful marker for the risk of cardiovascular disease.

Relationship of arterial compliance and blood pressure with microalbuminuria and mildly decreased glomerular filtration rate: a Chinese community-based analysis

OBJECTIVE

This analysis is designed to determine the prevalence of microalbuminuria (MAU) and mildly decreased glomerular filtration rate (GFR); to investigate the association of augmentation index (AIx), central blood pressure (cBP) and peripheral blood pressure (pBP) with MAU and mildly decreased GFR; and to compare the association strength of cBP and pBP with MAU and mildly decreased GFR.

METHODS

This community-based analysis included 2071 Chinese residents. Urine albumin-to-creatinine ratio (UACR), GFR, and pulse wave measurements were performed. UACR of 30-299 mg/g and GFR of 60-89 ml/min/1.73 m2 were identified as MAU and mildly decreased GFR.

RESULTS

The prevalence of MAU and mildly decreased GFR was 21.3% and 33.2%. The AIx, cBP and pBP were significantly higher in participants with MAU compared with those without MAU, and in participants with mildly decreased GFR compared with those without mildly decreased GFR (all P<0.001). After participants were categorized into four subgroups based on the presence or absence of MAU and mildly decreased GFR, Aix, cBP and pBP progressively increased from the subgroup without both of MAU and mildly decreased GFR to the subgroups with either one of them, and arrived at top in the subgroup with both of them (all P<0.001). Compared with the reference category without MAU and mildly decreased GFR, the odd ratio values significantly increased from the category with either one of MAU and mildly decreased GFR to the category with both of them (all P<0.001). The AIx, cBP and pBP were all independently associated with MAU and mildly decreased GFR after full adjustment (all P<0.05), and the association strength of MAU and mildly decreased GFR with cBP was similar to those with pBP.

CONCLUSIONS

In Chinese community-dwelling population, there was a high prevalence of MAU and mildly decreased GFR. The AIx, cBP and pBP were all independently associated with MAU and mildly decreased GFR; meanwhile, cBP did not exhibit stronger association with MAU and mildly decreased GFR compared with pBP.

Microalbuminuria in children with primary and white-coat hypertension

Microalbuminuria serves as an early marker of hypertension-related renal damage in adults. However, data on the prevalence of microalbuminuria in paediatric hypertensive patients in general and in children with white-coat hypertension (WCH) specifically are lacking. The aim of our study was to investigate the prevalence of microalbuminuria in children with primary hypertension (PH) and WCH, respectively. This was a retrospective case review of children with PH and WCH treated at three paediatric nephrology centres. Untreated children with either form of hypertension for whom measurements of urinary albumin excretion (UAE) had been performed were enrolled in the study. The study cohort comprised 52 children (39 boys) with hypertension (26 children with PH, 26 with WCH). Microalbuminuria (>3.2 mg/mmol creatinine) was present in 20% of children with PH and none of the children with WCH (p < 0.01). Children with PH had a higher median UAE than those with WCH (1.27 ± 1.92 vs. 0.66 ± 0.46 mg/mmol creatinine, p < 0.05). Based on these results, we suggest that children with PH have an increased prevalence of microalbuminuria, while children with WCH show no signs of hypertension-related renal damage.

Age and the difference between awake ambulatory blood pressure and office blood pressure: a meta-analysis

BACKGROUND

Ambulatory blood pressure (BP) (ABP) is a better predictor of adverse cardiovascular events than office BP (OBP). Owing to the extensive literature on the 'white coat effect', it is widely believed that ABP tends to be lower than OBP, with statements to this effect in Joint National Committee VII. However, recent evidence suggests that the difference varies systematically with age.

METHODS

We searched PubMed to identify population studies, published before April 2009, which assessed OBP and either ABP or home BP (HBP). On account of significant heterogeneity in the outcomes, random effect models were used for the meta-analyses.

RESULTS

OBP increased with age more steeply than awake ABP. OBP became higher than awake systolic/diastolic ABP at the age of 51.3/42.7 years in men (13 studies, N=3562) and 51.9/42.3 years in women (11 studies, N=2585). In the data in which OBP and HBP were measured (eight studies, N=4916), OBP was higher than HBP at all ages. In the data in which OBP, awake ABP, and HBP were all measured (two studies, N=895), awake ABP was higher than HBP at younger ages, becoming similar at the older age.

CONCLUSION

OBP tends to be higher than awake ABP only after the age of 50 years for systolic and after the age of 45 years for diastolic BP, but is lower than ABP at younger ages; in contrast OBP tends to exceed HBP at all ages.

Urinary albumin excretion among nondipper hypertensive patients is closely related with the pattern of nondipping

The relationship between 24-hour urinary albumin excretion (UAE) rate and the pattern of nondipping (isolated systolic nondipping, isolated diastolic nondipping, and both systolic and diastolic nondipping) is not known. Medical history, physical examination, laboratory analysis, and office and ambulatory blood pressure measurements were performed. Twenty-four hour urine specimens were collected to determine creatinine clearance and UAE. In total, 158 essential hypertensive patients (104 dippers, 54 nondippers) were included. Fourteen patients were isolated systolic nondippers, 7 patients were isolated diastolic nondippers, and 33 patients were both systolic and diastolic nondippers. Among nondipper patients, 17 had microalbuminuria and, among dipper patients, 9 had microalbuminuria (P<.0001). The median UAE of dippers was lower when compared with nondippers (5.25 mg/day vs.23 mg/day, P<.0001). The median UAE of isolated systolic nondippers, isolated diastolic nondippers, and both systolic and diastolic nondippers were 8.45 mg/day, 7.7 mg/day, and 25.5 mg/day, respectively (P=.001). Subgroup comparison of patients revealed that UAE was higher in patients with both systolic and diastolic nondippers when compared with dippers (P<.0001), isolated systolic nondippers (P=.001), and isolated diastolic nondippers (P=.017). Not only nondipping itself, but nondipping profile may be related with UAE in essential hypertensive patients.

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.

Prognostic significance of the white coat hypertension in patients with type 1 diabetes mellitus

Despite the high prevalence of white coat hypertension (WCH) in diabetes mellitus and the evidence that hypertension is a clear risk factor for the development of microalbuminuria (MA) in these patients, there is no information on the long-term prognostic significance of this condition in the diabetic population. We studied the evolution of 40 patients with type 1 diabetes mellitus (Type 1 DM). Twenty patients with WCH (office blood pressure> or =140/90mmHg associated with mean daytime blood pressure<135/85mmHg) classified as the WCH group and 20 patients with type 1 DM with a similar age and disease evolution, but who were normotensive, (office blood pressure<140/90mmHg associated with mean daytime blood pressure<135/85mmHg) classified as the normotensive control group. After 5 years of follow-up, MA appeared in four subjects and sustained hypertension in another, with a total of 31% of events in the WCH group, with none in the normotensive group. Kaplan-Meier analysis showed that the relative risk of developing these hypertensive events was 25% higher in the WCH group. At baseline, the night time systolic and diastolic blood pressure levels were significantly higher in patients who further developed MA and sustained hypertension. The findings in this study highlight the clinical importance of careful follow-up of type 1 diabetic patients with WCH.

[Proteinuria]

Several health organizations recommend that people be regularly checked for proteinuria to detect and treat kidney disease before it progresses. Proteinuria detected by a simple dipstick test should be confirmed by a quantitative measurement to assess persistent proteinuria. Most proteins are too big to pass through the kidneys' filters into the urine unless the kidneys are damaged. Markers of kidney damage in addition to proteinuria include abnormalities in the urine sediment, ultrasound of the kidneys and estimation of kidney function (creatinemia to calculate glomerular filtration rate). These assessments provide clues to the type (diagnosis) of chronic kidney disease and will the risk for developing progressive kidney failure. Thus, early detection of kidney disease will result in a more timely introduction of therapy that may slow the course of kidney disease. Microalbuminuria (albumin excretion above the normal range) that a marker of microvascular lesions in diabetes and hypertension is associated with a worth cardiovascular prognosis. Level of proteinuria in excess of 3,0 g/d in glomerular disease strongly determines the extent of kidney damage and renal prognosis.

Increased circulating concentrations of asymmetric dimethylarginine (ADMA) in white coat hypertension

Elevated plasma levels of the endogenous nitric oxide (NO) synthase inhibitor asymmetric dimethylarginine (ADMA) contribute to endothelial dysfunction and seem to be a predictor for cardiovascular mortality. Elevated ADMA plasma concentrations have been demonstrated in patients with hypertension. However, the plasma concentrations of ADMA in white coat hypertension (WCH) has not been previously studied. The aim of this study was to evaluate ADMA in WCH and compare with normotensive (NT) and hypertensive (HT) patients. We also evaluated the relation between ADMA and NO in these three groups. For this purpose, 34 NT, 34 white coat hypertensive (clinical hypertension and ambulatory daytime blood pressure <135/85 mmHg) and 34 HT patients were recruited in this study. The subjects were matched for age, gender, body mass index (BMI) and the patients with smoking habit, dyslipidaemia and diabetes mellitus were excluded. The ADMA levels were determined by high performance liquid chromatography. Plasma ADMA levels were significantly higher in WCH group than in the NT group (3.21+/-0.49 micromol/l vs 2.84+/-0.58 micromol/l, P=0.046). It was significantly higher in the HT group than in the NTs (4.24+/-0.38 micromol/l, P<0.001). There was also a significant difference between the HT and WCH groups (P<0.001). The WCH subjects had significantly higher levels of NO than the HTs (41.68+/-2.23 vs 32.18+/-2.68 micromol/l; P<0.001) and significantly lower values than the NTs (48.24+/-4.29 micromol/l; P<0.001). In WCH and HT group, there was a negative correlation between ADMA and NO (r=-0.515, P=0.003 and r=-0.389, P=0.034, respectively). In NT subjects, there was no correlation between these two parameters (r=-0.287, P=0.124). The correlation between ADMA and NO was stronger in WCH group than in HT group. Although NO levels in HT patients were lower than WCHs and ADMA levels were higher in HT patients than WCHs, the negative correlation of these two parameters were more pronounced in WCH group. Decreased NO and increased ADMA levels in WCH may indicate endothelial dysfunction. Our data indicate also that WCH represent an intermediate group between NT and HT when endothelial dysfunction is concerned.

Prevalence of masked uncontrolled and treated white-coat hypertension defined according to the average of morning and evening home blood pressure value: from the Japan Home versus Office Measurement Evaluation Study

OBJECTIVE

To evaluate the prevalence of masked uncontrolled and treated white-coat hypertension defined according to the average of morning and evening home blood pressure values.

METHODS

The study population consisted of 3303 essential hypertensive outpatients receiving antihypertensive treatment in Japan. Information on the characteristics of the patients was collected by a physician's self-administrated questionnaire. The office blood pressure value was calculated as the average of the four readings in two visits. All patients were asked to measure their blood pressure once every morning and once every evening. In the study, we included patients with at least three measurements in the morning and in the evening, respectively. The average of all home blood pressure values was taken as the home blood pressure value.

RESULTS

The mean value of home systolic/diastolic blood pressure was 136.8/79.3 mmHg, and the mean value of office systolic/diastolic blood pressure was 142.8/80.6 mmHg. Of the 3303 patients, 758 (23.0%) had controlled hypertension (home <135/85 mmHg and office <140/90 mmHg), 628 (19.0%) had masked uncontrolled hypertension (home > or =135/85 mmHg and office <140/90 mmHg), 640 (19.4%) had treated white-coat hypertension (home <135/85 mmHg and office > or =140/90 mmHg), and 1277 (38.7%) had uncontrolled hypertension (home > or =135/85 mmHg and office > or =140/90 mmHg).

CONCLUSIONS

Treated white-coat hypertension and masked uncontrolled hypertension were often observed in clinical settings. Physicians need to understand the prevalence of such patients to prevent inadequate diagnosis and treatment in them.

Hyperhomocysteinemia: an additional risk factor in white coat hypertension

The association between homocysteine and sustained hypertension (HT) has been studied. The aim of this study was to assess homocysteine levels in white coat hypertension (WCH) as an indicator of increased risk in the development of cardiovascular diseases. WCH was defined as clinical hypertension and a daytime ambulatory blood pressure of < 135/85 mmHg. Plasma levels of homocysteine were determined in patients with WCH, hypertension, and normotension (NT). The study group included 100 subjects, 33 with WCH (16 males, 17 females) aged 49.1 +/- 1.9; 35 sustained hypertensives (17 males,18 females) aged 48.5 +/- 1.7 and 32 normotensive control subjects (15 males, 17 females) aged 48.8 +/- 2.2. The subjects were matched for age, gender, and body mass index. Patients with a smoking habit, dyslipidemia, or diabetes mellitus were not included in the study. Homocysteine levels were analyzed by ELISA. Plasma homocysteine levels were significantly higher in the WCH group compared to the controls (12.32 +/- 1.07 versus 5.35 +/- 1.38 micromol/L; P < 0.001) and the WCH group had significantly lower homocysteine values than the hypertensives (19.03 +/- 0.76 micromol/L P < 0.001). Total cholesterol and tri-glycerides were not different among the groups. There were no statistically significant differences in urinary albumin excretion (UAE) or creatinine clearance between the three groups. Hypertensive retinopathy was observed in the WCH group, but was less severe and less frequent compared to HTs. LVMI was greater in the WCH group compared to the NTs, but significantly less than HTs. The data demonstrate that WCH is associated with high levels of homocysteine. The increase in homocysteine level in WCH is not as high as in SHT. Since an elevated plasma homocysteine level is a strong risk factor for coronary artery disease and there was target organ damage in our WCH group, we conclude that WCH should not be considered to be an innocent trait.

Prevention of the progression of chronic kidney disease: practice in China

With the epidemic rise of end-stage renal disease (ESRD) in many countries of the world, there is an urgent need to develop and implement strategies aiming at preventing the development and progression of chronic kidney disease (CKD), and the situation is the same in China. Glomerulonephritis is still the most common cause of ESRD in China; however, epidemiologic studies have revealed that the prevalence of diabetes and hypertension, which both are major causes of ESRD in many developed countries, are increasing dramatically. Additional studies about the prevalence of albuminuria in diabetes mellitus (DM) patients, and the prevalence of kidney lesion in certain high-risk population (e.g., hypertension and atherosclerosis) are undergoing. According to a questionnaire survey and some reports, education program for Chinese nephrologists and practitioners should to be strengthened.

Endothelium and angiogenesis in white coat hypertension

Hypertensive patients are at particular risk of cardiovascular complications, possibly related to endothelial damage or dysfunction, or to abnormal angiogenesis. The aim of this study was to compare the risk conferred by white coat hypertension (WCH) vs sustained hypertension in the development of the endothelial dysfunction and abnormal angiogenesis by evaluating nitric oxide (NO=NO2+NO3), endothelin-1 (ET-1), vascular endothelial growth factor (VEGF), and E-selectin levels in plasma. The study group included 102 subjects, 34 with WCH (17 male and 17 female patients) aged 49+/-11 years, 34 sustained hypertensives (HT) (15 male and 19 female patients) aged 47+/-11 years and 34 normotensive control subjects (NT) (16 male and 18 female patients) aged 48+/-10 years. WCH was defined as clinical hypertension and daytime ambulatory blood pressure less than 135/85 mmHg. The subjects were matched for age, gender, body mass index and the patients with smoking habit, dyslipidaemia, and diabetes mellitus were excluded from the study. The NO, ET-1, VEGF and E-selectin levels were analysed by ELISA technique. The WCH subjects had significantly higher levels of NO than the HT (41.68+/-2.23 vs 32.18+/-2.68 micromol/l; P<0.001) and significantly lower values than the NT (48.24+/-4.29 micromol/l; P<0.001). ET-1 levels of the WCH group were significantly higher than the NT (8.10+/-0.92 vs 5.95+/-0.26 ng/ml; P<0.001) and significantly lower than the HT (11.46+/-0.59 ng/ml; P<0.001). Considering with VEGF, the WCH group had significantly higher levels than the NT (195.88+/-11.84 vs 146.26+/-18.67 pg/ml; P<0.001), but the difference from the HT group was not significant (203.35+/-7.48 pg/ml; P=0.062). E-selectin in the WCH group was significantly lower than the HT (4.77+/-0.52 vs 8.49+/-2.85; P<0.001), but the difference from the NT group was not significant (3.86+/-0.67; P=0.077). Our data demonstrate that WCH is associated with endothelial dysfunction and abnormal angiogenesis. The degree of these changes is not as severe as observed in hypertensive population.

Protective Effects of an Angiotensin II Receptor Blocker and a Long-Acting Calcium Channel Blocker against Cardiovascular Organ Injuries in Hypertensive Patients

The purpose of this study is to compare the long-term effects of an angiotensin II receptor blocker (ARB) and a long-acting calcium channel blocker (CCB) on left ventricular geometry, hypertensive renal injury and a circulating marker of collagen synthesis in hypertensive patients. Patients with essential hypertension (24 men and 19 women; age, 37-79 years) were treated with a long-acting CCB, amlodipine (AML; 2.5-7.5 mg once daily) for 6 months. Then, AML was switched to an ARB, candesartan (CS; 4-12 mg once daily), in 22 patients (CS group), while AML was continued in the remaining 21 patients for another 6 months (AML group). At the end of each treatment period, ambulatory blood pressure monitoring (ABPM), echocardiography and sampling of blood and urine were performed. The average office blood pressure during the latter period was comparably controlled in the AML and the CS groups (AML: 130 +/- 8/87 +/- 7 mmHg; CS: 133 +/- 11/ 88 +/- 7 mmHg), while the average systolic blood pressure of 24-h ABPM was significantly lower in the AML than in the CS group (127 +/- 9 vs. 133 +/- 14 mmHg, p<0.05). Consequently, the left ventricular mass index was significantly decreased in the AML group (102 +/- 18 to 92 +/- 12 g/m2, p<0.05), while the change was insignificant in the CS group (103 +/- 25 to 98 +/- 21 g/m2). On the other hand, plasma procollagen I C-terminal peptide (PICP), a marker of collagen synthesis, was lowered by CS (86 +/- 21 to 70 +/- 21 ng/ml, p<0.01), but was not significantly affected by AML (80 +/- 127 to 74 +/- 91 ng/ml). CS reduced urinary albumin excretion (57 +/- 123 to 26 +/- 33 mg/g creatinine, p<0.05), but AML did not bring about significant changes (85 +/- 27 to 73 +/- 19 mg/g creatinine). The results suggested that long-acting CCBs are effective in improving left ventricular hypertrophy by controlling 24-h blood pressure, while ARBs possess protective effects against cardiovascular fibrosis and renal injury beyond their antihypertensive effects.

Target organ damage and changes in arterial compliance in white coat hypertension. Is white coat innocent?

The aim of this study was to perform an extensive evaluation of target organ status, metabolic abnormalities and hemodynamic alterations in white coat hypertension (WCH). Fifty normotensive (NT), 90 WCH (ambulatory daytime blood pressure < 135/85 mmHg) and 101 hypertensive (HT) subjects underwent extensive biochemical, echocardiographic, fundoscopic examination. In a subgroup study, arterial compliance and intima-media thickness (IMT) were measured by Doppler ultrasound in left common carotid artery. WCH subjects were found to have higher body mass index (BMI) than the NTs (p = 0.042). Left ventricle mass index (LVMI) was greater in the WCHs than the NTs (p < 0.001), but significantly less than the HTs (p < 0.001). Hypertensive retinopathy was observed in the WCHs, but was less severe and rare compared to the HTs (13% vs 27%). Both WCHs and HTs had high levels of urinary albumin excretion (UAE) (p = not significant). Total cholesterol was higher in WCHs than in the NTs (p = 0.04) The distensibility coefficient (DC) of the WCHs was significantly greater than the HTs (p < 0.01), while significantly smaller than the NTs (p < 0.01). The compliance coefficient (CC) of the WCHs was significantly higher than the HTs (p < 0.01), and significantly less than the NTs (p < 0.01). The IMT in the HTs was significantly higher than the WCHs (0.81 +/- 0.05 vs 0.70 +/- 0.04 mm; p < 0.001) and the NTs (p < 0.001). The difference between the NTs and the WCHs was not significant. Our data indicate that patients with WCH represent an intermediate group between NTs and sustained HTs where target organ damage and cardiovascular risk is concerned.

White coat hypertension is a cardiovascular risk factor: a 10-year follow-up study

The objective of this paper was to evaluate the cardiovascular risk in white coat hypertension (WCH). WCH is a well-known clinical entity defined by persistently elevated blood pressure (BP) in the doctor's office, whereas BP in other conditions is normal. The prognosis of WCH is unsettled, although two prospective studies that include normal control groups imply that the condition is benign. This study is a 10-year follow-up study on 420 patients with grade I-II hypertension newly diagnosed by their general practitioner and 146 normal controls (NTs). Ambulatory blood pressure (ABP) monitoring was performed at baseline. With our protocollated cutoff value of daytime-ABP <135/90 mmHg, 76 (18.1%) of the 420 hypertensives were white coat hypertensives (WCHs) and 344 were established hypertensives (EHs). With a lower cutoff of 135/85 mmHg, 40 (9.5%) were WCHs. Complete follow-up data were obtained for all 566 subjects. The mean duration of follow-up was 10.2 years (range 9.0-12.5). In the WCH group, 14 first events were recorded (18.4%) consisting of two cardiovascular deaths and 12 nonfatal cardiovascular events. In the EH group, the corresponding number of events were 56 first events (16.3%), 12 cardiovascular deaths and 44 nonfatal cardiovascular events, and in the NT group 10 first events (6.8%), two cardiovascular deaths and eight nonfatal cardiovascular events. The event rate was similar in the WCH group and the EH group and significantly lower in the NT group (P<0.05). When corrected for daytime-ABP, age and other confounders, the difference remained statistically significant. When using the lower cutoff of 135/85 mmHg, WCH was still associated with a significantly higher cardiovascular event rate. In conclusion, the main finding of this 10-year follow-up study is an increased cardiovascular risk in WCH compared to normotensive controls.

24-h Ambulatory blood pressure in patients with ECG-determined left ventricular hypertrophy: left ventricular geometry and urinary albumin excretion—a LIFE substudy

This study was undertaken to evaluate the relationships among left ventricular (LV) geometric patterns and urinary albumin excretion in patients with hypertension and electrocardiographic (ECG) LV hypertrophy. In 143 patients with stage II-III hypertension, 24-h ambulatory blood pressure (BP) monitoring, single urine albumin determination, and echocardiography were performed after 14 days of placebo treatment. Mean age was 68+/-7 years, 35% were women, body mass index was 28+/-5 kg/m(2), LV mass index (LVMI) was 125+/-26 g/m(2), and 24% had microalbuminuria. The mean office BP was 176+/-15/99+/-8 mmHg and the mean daytime ambulatory BP was 161+/-18/92+/-12 mmHg. Ambulatory BP, but not office BP, was higher among albuminuric compared to normoalbuminuric patients. In patients with established hypertension, daytime pulse pressure and office BP were different in the four patterns of LV geometry, with the highest pressure in those with abnormal geometry. Furthermore, microalbuminuria was more frequent in hypertensive patients with LV hypertrophy than in those with either normal geometry or concentric remodelling. White coat hypertensives (10%) showed lower LVMI and no microalbuminuria compared to patients with established hypertension. There were no differences in the prevalence of nondippers (26%) among the four LV geometric patterns or in microalbuminuria. In conclusion, increased daytime pulse pressure and office BP were associated with increased prevalence of abnormal LV geometry. Microalbuminuria was more frequent in groups with concentric and eccentric LV hypertrophy. Ambulatory BP, but not office BP, was higher in albuminuric than normoalbuminuric patients. With regard to the relationship among BP, LV geometric patterns, and urine albumin excretion in this population, 24-h ambulatory BP did not provide additional information beyond the office BP.

Circulating homocysteine levels in sustained and white coat hypertension

Although white coat hypertension has been widely studied in the last years, its risk profile is not yet completely clear. The aim of this study was to evaluate circulating homocysteine levels, an emerging cardiovascular risk factor, in subjects with white coat and sustained hypertension. We selected 31 sustained hypertensive subjects, 31 white coat hypertensive subjects and 31 normotensive subjects matched for age, gender, body mass index and occupation. Women were also matched for menopausal status. Subjects with smoking habit, dyslipidaemia and diabetes mellitus were excluded from the study. White coat hypertension was defined as clinical hypertension and daytime ambulatory blood pressure <135/85 mmHg. Blood samples were drawn after a fasting period of 12 h for routine laboratory tests and homocysteine determination. Homocysteine levels were evaluated by fluorescence polarization immunoassay. Creatinine, glucose, cholesterol and triglycerides were not different among the groups. White coat hypertensive subjects had significantly lower homocysteine levels than sustained hypertensive patients (8.2+/-2.0 vs 12.6+/-3.9 micromol/l, P=0.0003). No significant difference was observed between white coat hypertensive and normotensive subjects regarding this parameter (8.2+/-2.0 vs 7.6+/-1.9 micromol/l, P=0.9). In conclusion, our data show that middle-aged white coat hypertensive subjects without other cardiovascular risk factors have lower circulating homocysteine levels than sustained hypertensive patients suggesting that they are at lower cardiovascular risk.

Blood pressure and cardiac autonomic function in relation to risk factors and treatment perspectives in Type 1 diabetes

The cumulative incidence of diabetic nephropathy in Type 1 diabetes mellitus is in the order of 25 30%. The recognition that elevated blood pressure (BP) is a major factor in the progression of these patients to end-stage renal failure has led to the widespread use of antihypertensive therapy in order to preserve glomerular filtration rate and ultimately to reduce mortality. The routine measurement of microalbuminuria allows early identification of the subgroup of patients at increased risk of developing clinical nephropathy. Microalbuminuric Type 1 diabetic patients show a number of characteristic pathological abnormalities. In addition to elevated BP and abnormal circadian rhythm, there are also associated abnormalities of vagal function, lipid profile and endothelial function, as well as an increased prevalence of retinopathy. The first section of this two-part review focusses on the early changes associated with renal involvement in Type 1 diabetes. It addresses the associations between urinary albumin excretion, glycaemic control, smoking, BP, circadian BP variation, QT interval abnormalities and autonomic function in three groups of patients; those with normoalbuminuria, those progressing towards microalbuminuria and those with established low-grade microalbuminuria.

Classification of blood pressure levels by ambulatory blood pressure in hypertension

Whereas clinic blood pressure (CBP) above normality is divided into stages, no corresponding classifications are available for 24-hour ambulatory blood pressure (ABP). We conducted a study (1) to define stages of hypertension by ABP corresponding to CBP stages and (2) to evaluate if these stages have prognostic impact similar to CBP stages. Seven hundred thirty-six hypertensive patients were included. Mean systolic blood pressure was 149+/-15.2/87+/-8.6 mm Hg for CBP and 135+/-13/79+/-9.7 mm Hg for ABP. The mean bias between both methods was -13.3 mm Hg (95% CI, -14.3 to -12.2; 1.96xSD limits of agreement, 15.7 to -42.3) and -7.3 mm Hg (95% CI, -7.9 to -6.6; 1.96xSD limits of agreement, 9.8 to -24.3) for systolic and diastolic blood pressure (P>0.0001 for both), respectively. Classification of hypertension by ABP revealed lower cutoff values for the different stages of hypertension compared with the corresponding cutoff values for CBP (CBP versus ABP: 140/90 versus 132/81 mm Hg; 160/100 versus 140/88 mm Hg; 180/110 versus 148/94 mm Hg, P<0.001). Overall, 82 (11.1%) patients had nonfatal clinical cardiovascular events and 9 (1.2%) patients died of a cardiovascular cause during follow-up. The distribution of cardiovascular events was significantly associated with increasing ABP value (P<0.006). Staging of hypertension by ABP may facilitate the use of this method in daily clinical practice, as ABP can now be used not only to confirm the diagnosis of hypertension but also to assess the severity and prognosis of hypertensive disease.

Microalbuminuria, cardiovascular, and renal risk in primary hypertension

Microalbuminuria is defined as abnormal urinary excretion of albumin between 30 and 300 mg/d. It can be measured accurately by several widely available and sensitive methods. This abnormality can be found in 8 to 15% of nondiabetic patients with primary hypertension, although its prevalence varies greatly in the literature, likely due to differences in the methods used to detect it and to the criteria applied in the selection of patients. The pathogenetic mechanisms leading to the development of microalbuminuria are still not completely known. BP load and increased systemic vascular permeability, possibly due to early endothelial damage, seem to play a major role. Increased urinary albumin excretion has been associated with several unfavorable metabolic and nonmetabolic risk factors and subclinical hypertensive organ damage. In fact, a higher prevalence of concentric left ventricular hypertrophy and subclinical impairment of left ventricular performance, as well as the presence of carotid atherosclerosis, have been reported in patients with microalbuminuria. These associations might per se justify a greater incidence of cardiovascular events. Long-term longitudinal studies have recently confirmed the unfavorable prognostic significance of microalbuminuria in hypertensive patients. It has also been hypothesized that microalbuminuria might be a forerunner of overt renal damage in primary hypertension. Clinical studies, however, have shown conflicting results, and this hypothesis has to be considered tempting but speculative at present. In conclusion, microalbuminuria is a specific, integrated marker of cardiovascular risk and target organ damage in primary hypertension and one that is suitable for identifying patients at higher global risk. A wider use of this test in the diagnostic work-up of hypertensive patients is recommended.

Different metabolic predictors of white-coat and sustained hypertension over a 20-year follow-up period: a population-based study of elderly men

BACKGROUND

The clinical significance of white-coat hypertension is still unclear. Moreover, no study has examined metabolic predictors of white-coat versus sustained hypertension.

METHODS AND RESULTS

We investigated men (n=602) in a longitudinal population-based cohort who at age 70 years were identified as normotensive, white-coat hypertensive (office blood pressure [BP] > or =140/90 and daytime ambulatory BP <135/85 mm Hg), and sustained hypertensive (office BP > or =140/90 and daytime ambulatory BP > or =135/85 mm Hg). At baseline, when the subjects were aged 50 years, blood glucose, insulin, lipids, and fatty acid composition of the serum cholesterol esters were analyzed. The investigations at age 70 years included determination of insulin sensitivity and target organ damage. At age 50 years, individuals who 20 years later were identified as white-coat hypertensive or sustained hypertensive showed significantly elevated BP, heart rate, and impaired glucose tolerance compared with normotensive subjects but white coat hypertensive subjects were leaner and had a more favorable serum cholesterol ester fatty acid profile than did sustained hypertensive subjects. At age 70 years, both white-coat and sustained hypertensive subjects showed an impaired insulin sensitivity, elevated blood glucose, and increased serum insulin and heart rate compared with normotensive subjects, but left ventricular mass and urinary albumin excretion were increased only in sustained hypertensive subjects.

CONCLUSIONS

These findings indicate that although metabolic abnormalities and elevated heart rate were consistent over time in both hypertensive groups, a lower body mass index and more favorable dietary fat composition predicted the development of white-coat as opposed to sustained hypertension over 20 years.

[Medical stress and blood pressure]

BP measurement by a physician may trigger a blood pressure and heart rate increase often referred to as the white coat effect. This pressure response may occur both in normotensive and hypertensive subjects. The identification of such individuals is usually not possible on a clinical basis. This identification is however important because white coat effect and permanent hypertension do not share the same prognosis, the white coat effect being associated with a low rate of cardiovascular complications. To avoid an important overestimation of the real blood pressure level due to this white coat effect, it is possible to increase the delay before blood pressure measurements (beyond 15 minutes) or to take into account measurements made by nurses. Reading may also have a favorable consequence. However, a blood pressure recording outside the office, that is an ambulatory or a home blood pressure measurement, is the only way to confirm the presence of a white coat effect. The decision to treat is based on this measurement.

Microalbuminuria, an integrated marker of cardiovascular risk in essential hypertension

This paper reviews the existing epidemiological and clinical evidence about the relationships of non-diabetic microalbuminuria with cardiovascular risk factors such as elevated blood pressure (BP), systolic particularly, cardiac hypertrophy, adverse metabolic status, smoking habits, elevated angiotensin II levels, endothelial dysfunction, acute and perhaps subclinical inflammation. Because of that unique property of reflecting the influence of so many clinically relevant parameters, microalbuminuria may legitimately be defined as an integrated marker of cardiovascular risk, an unique profile among the several prognostic predictors available to stratify risk in hypertensive patients. Recent cohort studies also showed associations with cardiovascular morbidity and mortality independently from conventional atherogenic factors. This behaviour, whose understanding still needs further elucidation, suggests to measure albuminuria and to screen patients at a higher absolute risk in whom preventive treatment is expected to be more beneficial than in those with a lower absolute risk.

Comparison of the effects of amlodipine and losartan on 24-hour ambulatory blood pressure in hypertensive patients

Effects of amlodipine (AML), a long-acting calcium antagonist, and losartan (LOS), an angiotensin II receptor antagonist, on 24-hr blood pressure profile were compared in 15 patients with essential hypertension. After 4 weeks of placebo period, the patients were treated with AML or LOS in a random crossover design for 12-16 weeks each. Either drug was given once daily at 0800 and the doses were titrated so that the office blood pressure was reduced lower than 140/90mmHg. At the end of each period, 24-hr blood pressure was monitored. Average office blood pressure was lowered from 158 +/- 2/ 98 +/- 2 mmHg to 134 +/- 1/87 +/- 1 mmHg by AML and 134 +/- 2/88 +/- 1 mmHg by LOS. Average 24-hr blood pressure was also reduced from 144 +/- 3/ 92 +/- 2 mmHg to 131 +/- 2/84 +/- 2 mmHg by AML and 135 +/- 3/85 +/- 2 mmHg by LOS. The averaged 24-hr systolic blood pressure was significantly lower in AML than in LOS (p < 0.05). Then, the 24-hr blood pressure was analyzed for four segments; morning (0530-0900 h), daytime (0930-1800 h), evening (1830-2300 h) and night (2330-0500 h). Although the daytime blood pressure was comparable between AML and LOS, systolic blood pressure in the evening and morning hours were lower in AML than in LOS (133 +/- 2 vs. 138 +/- 3mmHg,p<0.01; 129 +/- 3 vs. 134 +/- 4,p<0.05). Troughtopeakratio of antihypertensive effect on systolic blood pressure was significantly greater in AML than in LOS (62 +/- 5% vs. 55 +/- 4%, p < 0.05). Either drug did not cause reflective increase in pulse rate over 24 hours. These results suggest that both AML and LOS are equally effective in lowering daytime blood pressure without eliciting reflex tachycardia, however, the antihypertensive effect of AML lasts longer than that of LOS. Such information seems important to achieve 24-hr blood pressure control using these drugs.

Clinic and ambulatory heart rate in sustained and white-coat hypertension

BACKGROUND

Sustained and white-coat hypertensives show hypertension in the office setting but different blood pressure values outside the clinical environment. So far, only a few incomplete data on heart rate are available inside and outside the clinical setting in these groups of patient. The aim of this study was to evaluate clinic and ambulatory heart in sustained hypertensives, white-coat hypertensives and normotensives.

METHODS

We selected 236 sustained hypertensives, 236 white-coat hypertensives and 236 normotensives matched for age, gender and body mass index, and with a similar occupation. The subjects had been submitted to clinic evaluation and the non-invasive monitoring of blood pressure and heart rate. White-coat hypertension was defined as clinic hypertension and a daytime blood pressure of less than 135/85 mmHg.

RESULTS

The clinic heart rate was significantly higher in sustained hypertensives and white-coat hypertensives than in normotensives (76 +/- 11 versus 75.5 +/- 10 versus 70 +/- 9 beats/min [bpm], respectively, P < 0.05). The daytime heart rate was significantly higher in sustained hypertensives than in white-coat hypertensives and normotensives (79.4 +/- 10 versus 74.6 +/- 8.5 versus 74.5 +/- 8.5 bpm, respectively, P < 0.05), as were the night-time heart rate (67 +/- 8.5 versus 63 +/- 8 versus 63 +/- 8 bpm, respectively, P < 0.05) and 24 h heart rate (76.3 +/- 9 versus 72 +/- 7.8 versus 72 +/- 8 bpm, respectively, P < 0.05). When men and women were analyzed separately, the same trend was observed.

CONCLUSIONS

The clinic heart rate is similar in sustained and white-coat hypertensives, but the ambulatory heart rate is lower in white-coat hypertensives. As ambulatory heart rate is more representative of 24 h heart rate load and may be a better indicator of the detrimental effect of heart rate, our findings suggest that white-coat hypertensives are at lower cardiovascular risk than sustained hypertensives.

Association of urinary albumin concentration with casual and ambulatory blood pressure: a similar relationship in normotensive and hypertensive subjects

BACKGROUND

The urinary albumin level has been found to be positively correlated with blood pressure in hypertensive patients. To our knowledge, this relationship has not been evaluated in normotensive subjects and compared with that in hypertensives using casual and ambulatory blood pressure measurements.

METHODS

In this cross-sectional study, a cohort of 234 normotensive and hypertensive participants wore an ambulatory blood pressure monitor for 24 h, standardized casual blood pressure measurements being taken. The urinary albumin concentration was determined by the dipstick Micral Test. The bivariate and multivariate relationship between urinary albumin concentration and demographic and blood pressure measures was investigated using correlational and regression analyses.

RESULTS

The prevalence of microalbuminuria was significantly greater in the hypertensive than normotensive participants. The urinary albumin concentration was positively associated with both casual and ambulatory measures of blood pressure in both the normotensive and hypertensive subsamples, stronger correlations being found for systolic blood pressure. The relationship between systolic blood pressure and urinary albumin concentration was similar in the normotensive and hypertensive subsamples.

CONCLUSIONS

These findings confirm earlier reports of the greater prevalence of microalbuminuria in patients with hypertension than in normotensive participants, as well as those reporting a continuous relationship in hypertensive participants. This study extends prior research to a normotensive subsample, in whom a similar relationship of blood pressure to microalbuminuria, using both ambulatory and casual measures of blood pressure, was found. Future research should investigate the causal direction of this relationship.

Alterations of cardiac structure in patients with isolated office, ambulatory, or home hypertension: Data from the general population (Pressione Arteriose Monitorate E Loro Associazioni [PAMELA] Study)

BACKGROUND

The prevalence and clinical significance of isolated office (or white coat) hypertension is controversial, and population data are limited. We studied the prevalence of this condition and its association with echocardiographic left ventricular mass in the general population of the PAMELA (Pressione Arteriose Monitorate E Loro Associazioni) Study.

METHODS AND RESULTS

The study involved a large, randomized sample (n=3200) representative of the Monza (Milan) population, 25 to 74 years of age. Participants in the study (64% of the sample) underwent measurements of office, home, 24-hour ambulatory blood pressure, and echocardiography. Isolated office hypertension was defined as systolic or diastolic values >/=140 mm Hg or >/=90 mm Hg, respectively. Home and ambulatory normotension were defined according to criteria previously established from the PAMELA Study, for example, <132/83 mm Hg (systolic/diastolic) for home and 125/79 mm Hg for 24-hour average blood pressure. Treated hypertensive subjects were excluded from analysis that was made on a total of 1637 subjects. Depending on normotension being established on systolic or diastolic blood pressure measured at home or over 24 hours, the prevalence of isolated office hypertension ranged from 9% to 12%. In these subjects, left ventricular mass index was greater (P<0.01) than in subjects with normotension both in and outside the office. This was the case also for prevalence of left ventricular hypertrophy. Left ventricular mass index and hypertrophy were similarly greater in subjects found to have normal office but elevated home or ambulatory blood pressure ( approximately 10% of the population).

CONCLUSIONS

Isolated office hypertension has a noticeable prevalence in the population and is accompanied by structural cardiac alterations, suggesting that it is not an entirely harmless phenomenon. This is the case also for the opposite condition, that is, normal office but elevated home or ambulatory blood pressure, which implies that limiting blood pressure measurements to office values may not suffice in identification of subjects at risk.

Prediction of blood pressure level and need for antihypertensive medication: 10 years of follow-up

OBJECTIVE

To evaluate the usefulness of blood pressure and its variability in the prediction of future blood pressure and need for antihypertensive medication.

METHODS

We used WHO criteria to classify, at baseline, 97 healthy untreated male volunteers as normotensive (n = 34), borderline hypertensive (n = 29) or mild hypertensive (n = 34), with casual measurements before intra-arterial 24 h ambulatory blood pressure monitoring. After 10 years of follow-up, 87 of the men (90%) were available and their blood pressure was recorded using casual measurements and non-invasive ambulatory 24 h monitoring.

RESULTS

During the follow-up, the blood pressure classification deteriorated in 35 individuals (40%) and improved in six (7%) (McNemar test, P< 0.0001). In the borderline hypertensive group, 77% became hypertensive (P= 0.03). The 24 h mean systolic blood pressure was the best predictor of follow-up casual systolic (adj.R2 = 0.420) and 24 h systolic (adj.R2 = 0.540) blood pressure. The 24 h mean diastolic blood pressure was the best predictor of follow-up casual diastolic (adj.R2 = 0.301) and 24 h diastolic (adj.R2 = 0.292) blood pressure. The baseline casual systolic blood pressure also predicted the follow-up casual systolic blood pressure relatively well (adj.R2 = 0.356), but was clearly weaker for the follow-up 24 h systolic (adj.R2 = 0.275) blood pressure. The prediction of follow-up casual diastolic (adj.R2 = 0.259) and follow-up 24 h diastolic (adj.R2 = 0.214) blood pressure by baseline casual blood pressure was even weaker. The means and variabilities of the 24 h, daytime, and night-time blood pressures were the best predictors of the need for antihypertensive medication (Cox-Snell R2 = 0.399). The characteristics of the individual did not significantly predict future blood pressure and the need for antihypertensive medication.

CONCLUSIONS

The 24 h mean blood pressure was an excellent predictor of the future blood pressure and the need for antihypertensive medication. Prediction of antihypertensive medication was further improved by also using blood pressure variability. Systolic blood pressure was more predictable than diastolic blood pressure.

No impact of blood pressure variability on microalbuminuria and left ventricular geometry: analysis of daytime variation, diurnal variation and 'white coat' effect

OBJECTIVE

To investigate the influence of blood pressure variability on target organ involvement.

METHODS

Using a cross-sectional study of a hypertension clinic at a district general hospital, 420 patients with newly diagnosed untreated essential hypertension referred on a consecutive basis from general practice and 146 normal subjects drawn at random from the Danish National Register underwent a variety of measurements which included: echocardiography with determination of left ventricular mass index and relative wall thickness and early morning urine albumin/creatinine ratio. Mean, standard deviation and coefficient of variation of automated clinic values; daytime, night-time and full 24-h period were extracted from 24-h ambulatory blood pressure (ABP) monitoring. 'White coat' effect and dip were calculated. Hypertensives were classified into subjects with high or low variability, into 'white coat' hypertensives or established hypertensives and into dippers or non-dippers.

RESULTS

Standard deviation of daytime blood pressure (BP) was positively associated with target organ damage and BP level, which was not the case when variability was expressed as a coefficient of variation. Patients with high variability exhibited no more significant target organ damage than patients with low variability, but patients with established hypertension had significantly more target organ damage than the 'white coat' hypertensives. The 'white coat' effect as such was not associated with increased target organ involvement. Non-dippers had significantly more cardiac target organ damage than dippers, but the difference disappeared after correction for different 24-h BP level.

CONCLUSION

BP variability data obtained by non-invasive ABP monitoring does not seem to improve the information inherent in the BP level.

Frequency and determinants of microalbuminuria in mild hypertension: a primary-care-based study

OBJECTIVE

To evaluate the frequency of microalbuminuria and its relationship with several risk factors and left ventricular mass in a population of mildly hypertensive subjects attended in a primary-care setting.

DESIGN

Cross-sectional study.

SETTING

Eight primary-care centres.

PATIENTS

Two hundred and twenty-three non-diabetic patients recently diagnosed with mild hypertension were included in the study. None of them had clinical evidence of target-organ damage or had received prior antihypertensive treatment.

INTERVENTIONS

Subjects included in the study underwent clinical interview, measurement of blood pressure (BP) on three visits, blood analysis, measurement of albumin by immunonephelometry in three overnight urine collections, 24 h BP monitoring and M-mode and Doppler echocardiography.

MAIN OUTCOME MEASURES

Tobacco habit, clinic BP, body mass index, serum lipids and uric acid, glycaemia, urinary albumin excretion (UAE), ambulatory BP and left ventricular mass index.

RESULTS

The frequency of microalbuminuria was 7.2%. Microalbuminuric patients were more likely to be men and to be characterized by higher ambulatory BP, body mass index and uric acid levels. Regression analysis demonstrated that male sex and 24 h systolic BP were determinants of UAE. Patients with white-coat hypertension showed lower UAE than did subjects with sustained hypertension. Although a certain relationship between UAE and left ventricular mass index was found, these variables were not significantly correlated.

CONCLUSIONS

A low proportion of mildly hypertensive patients attended in a primary care setting are microalbuminuric. In this population, UAE is an expression of BP values over 24 h and correlates with several risk factors.