Increased nocturnal blood pressure in healthy prepubertal twins

AIM: To compare ambulatory blood pressure monitoring (ABPM) in twin children to a published singleton population, and to examine the influence of birthweight and fasting plasma cortisol on blood pressure. DESIGN: A cross-sectional study of monozygotic and dizygotic twins compared with a similar previously published normative control population. METHODS: Forty-four healthy prepubertal twin children aged 4-11 years (20 monozygotic, 22 male) were studied. All subjects had 24-h ABPM and a fasting early morning plasma cortisol. RESULTS: Twins had higher 24-h systolic blood pressure (BP) compared with controls with similar daytime and elevated night-time systolic BP (P > 0.3 and P < 0.01, respectively). Twins had reduced systolic and diastolic nocturnal BP dipping compared with controls (P < 0.0001 for both), and 61% of twins exhibited a < 10% fall in nocturnal BP. In the twin cohort there was no association between birth weight and daytime systolic BP (P = 0.6), nor any other ABPM parameter. There was no difference in BP parameters between dizygotic and monozygotic twins, and no difference between the lighter and heavier birthweight twins for any ABPM parameter. Fasting plasma cortisol was not associated with either birthweight (P = 0.2) or daytime systolic BP (P = 0.4). CONCLUSIONS: Healthy prepubertal twins have increased nocturnal BP and reduced nocturnal BP dipping independent of zygosity or birthweight. These abnormalities may be a risk factor for the later development of hypertension in twins. As these BP abnormalities are not associated with twin birth weight, the twin model may not be appropriate in investigating the fetal origins of disease in later adult life.     

Nocturnal dipping of heart rate and blood pressure in people with HIV in Tanzania

People with HIV (PWH) have a >2‐fold greater risk for development of cardiovascular disease (CVD), which may be associated with abnormalities in 24‐h ambulatory blood pressure measurement (ABPM) profile. We conducted a nested case‐control study of ABPM in 137 PWH and HIV‐uninfected controls with normal and high clinic blood pressure (BP) in Tanzania. Nocturnal non‐dipping of heart rate (HR) was significantly more common among PWH than HIV‐uninfected controls (p = .01). Nocturnal non‐dipping of BP was significantly more common in PWH with normal clinic BP (p = .048). Clinical correlates of nocturnal non‐dipping were similar in PWH and HIV‐uninfected adults and included higher BMI, higher CD4⁺ cell count, and high C‐reactive protein for HR and markers of renal disease for BP. In conclusion, nocturnal non‐dipping of both BP and HR was more common in PWH but further research is needed to determine causes and consequences of this difference.     

Reproducibility of nocturnal blood pressure fall in early phases of untreated essential hypertension: a prospective observational study

A number of studies have shown that a smaller than normal nocturnal blood pressure (BP) decrease is associated with cardiovascular disease. However, no large prospective studies have examined the reliability of nocturnal dipping within individuals. The aim of our study was to investigate the short-term variability of nocturnal BP fall in a large cohort of patients with recently diagnosed essential hypertension. In all, 414 uncomplicated never treated hypertensive patients referred to our outpatient hypertension hospital clinic (mean age 46+/-12 years; 257 M, 157 F) prospectively underwent: (1). repeated clinic BP measurements; (2). routine examinations recommended by WHO/ISH guidelines; and (3). ambulatory BP monitoring (ABPM) twice within a 4-week period. Dipping pattern was defined as a reduction in the average systolic and diastolic BP at night greater than 10% compared to average daytime values. Overall, 311 patients (75.1%) showed no change in their diurnal variations in BP. Of the 278 patients who had a dipping pattern on the first ABPM, 219 (78.7%) confirmed this type of profile on the second ABPM, while 59 (21.3%) showed a nondipping pattern. Among 37 dipper patients with >20% of nocturnal systolic BP decrease (extreme dippers), only 16 (43.2%) had this marked fall in BP on the second ABPM. Of the 136 patients who had a nondipping pattern on the first ABPM, 92 (67.6%) confirmed their initial profile on the second ABPM, while 44 (32.4%) did not. Patients with reproducible nondipping profile were older (48+/-12 years) than those with reproducible dipping profile (44+/-12 years, P<0.05). These findings indicate that: (1). short-term reproducibility of nocturnal fall in BP in untreated middle-aged hypertensives is rather limited: overall, one-fourth of patients changed their initial dipping patterns when they were studied again after a few weeks; (2). this was particularly true for extreme dipping and nondipping patterns; (3). abnormalities in nocturnal BP fall, assessed by a single ABPM, cannot be taken as independent predictors of increased cardiovascular risk.     

Ambulatory blood pressure is a better marker than clinic blood pressure in predicting cardiovascular events in patients with/without type 2 diabetes

BACKGROUND: The prognostic significance of ambulatory blood pressure (ABP) has not been established in patients with type 2 diabetes (T2DM). METHODS: In order to clarify the impact of ABP on cardiovascular prognosis in patients with or without T2DM, we performed ABP monitoring (ABPM) in 1,268 subjects recruited from nine sites in Japan, who were being evaluated for hypertension. The mean age of the patients was 70.4 +/- 9.9 years, and 301 of them had diabetes. The patients were followed up for 50 +/- 23 months. We investigated the relation between incidence of cardiovascular diseases (CVDs) and different measures of ABP, including three categories of awake systolic blood pressure (SBP <135, 135-150, and >150 mm Hg), sleep SBP (<120, 120-135, and >135 mm Hg), and dipping trends in nocturnal blood pressure (BP) (dippers, nondippers, and risers). Cox regression models were used in order to control for classic risk factors. RESULTS: Higher awake and sleep SBPs predicted higher incidence of CVD in patients with and without diabetes. In multivariable analyses, elevated SBPs while awake and asleep predicted increased risk of CVD more accurately than clinic BP did, in both groups of patients. The relationships between ABP level and CVD were similar in both groups. In Kaplan-Meier analyses, the incidence of CVD in nondippers was similar to that in dippers, but risers experienced the highest risk of CVD in both groups (P < 0.01). The riser pattern was associated with a approximately 150% increase in risk of CVD, in both groups. CONCLUSIONS: These findings suggest that ABPM is a better predictor of cardiovascular risk than clinic BP, and that this holds true for patients with or without T2DM.     

Importância da monitorização ambulatória da pressão arterial no diagnóstico e prognóstico da hipertensão arterial em idade pediátrica

The prevalence of high blood pressure (BP) at pediatric age has increased progressively, one of the causes of which is obesity. However, the dominant etiology in this age group is renal and/or cardiovascular pathology. Ambulatory blood pressure monitoring (ABPM) is the method of choice for the diagnosis of hypertension, especially in children at high cardiovascular risk. Its use is limited to children from five years of age. Choosing appropriate cuff size is key to obtaining correct blood pressure.The main indication for ABPM is to confirm the diagnosis of hypertension. It also allows the diagnosis of white coat hypertension (which may represent an intermediate stage between the normotensive phase and hypertension), or masked hypertension, associated with progression to sustained hypertension and left ventricular hypertrophy (LVH). Children with isolated nocturnal hypertension should be considered as having masked hypertension.BP load is defined as the percentage of valid measurements above the 95th percentile for age, gender, and height. Values above 25‐30% are pathological and those above 50% are predictive of LVH. ABPM correlates with target organ damage, particularly LVH and renal damage. It is useful in the differentiation of secondary hypertension, since these children show higher BP load and less nocturnal dipping, and confirmation of response to therapy. Thus ABPM allows the diagnosis and classification of hypertension, provides cardiovascular prognostic information and identifies patients with intermediate phenotypes of hypertension.     

Blood Pressure Profiles 5 to 10 Years After Transplant in Pediatric Solid Organ Recipients

Arterial hypertension is a major risk factor for cardiovascular disease after solid organ transplantation, emphasizing the need for blood pressure (BP) monitoring. The authors studied 24‐hour ambulatory BP monitoring (ABPM) parameters (index, load, dipping) and their predictive value with regard to hypertension as well as correlations with graft function and metabolic parameters such as obesity and dyslipidemias. The ABPM profiles of 111 renal, 29 heart, and 13 liver transplant recipients were retrospectively analyzed 5 to 10 years after transplant (median 5.1 years). The BP profiles among the different transplant groups were similar. The BP index and load were abnormal especially at nighttime and the nocturnal BP dipping was often blunted (in 49% to 83% of the patients). The BP variables were found to be equally valued when assessing hypertension. BP load of 50% instead of 25% seems to be a more adequate cutoff value. The BP variables correlated poorly with the metabolic parameters and kidney function. Antihypertensive medication did not notably change the ABPM profile in renal transplant recipients. Hypertension, including nocturnal hypertension, is present in children receiving solid organ transplant, underlining the importance of use of ABPM in the follow‐up of these patients.     

Cardiovascular target organ damage in essential hypertensives with or without reproducible nocturnal fall in blood pressure

OBJECTIVE: The clinical significance of classifying patients as dippers and non-dippers on the basis of a single period of ambulatory blood pressure monitoring (ABPM) has been questioned. The aim of this study was to evaluate the relationship between nocturnal dipping status, defined on the basis of two periods of ABPM, and cardiac and extracardiac target organ damage in essential hypertension. METHODS: A total of 375 never-treated essential hypertensive patients [mean 24-h blood pressure (BP) > or = 125/80 mmHg; mean +/- SD age 45.9 +/- 11.9 years] referred for the first time to our outpatient clinic underwent the following procedures: (i) repeated clinic BP measurements; (ii) blood sampling for routine chemistry examinations; (iii) 24-h urine collection for microalbuminuria; (iv) ABPM over two 24-h periods within 4 weeks; (v) echocardiography; and (vi) carotid ultrasonography. RESULTS: A reproducible nocturnal dipping (decrease in BP > 10% from mean daytime BP in both ABPM periods) and non-dipping profile (decrease in BP < or = 10% in both ABPM periods) was found in 199 (group I) and 79 patients (group II), respectively; 97 patients (group III) had a variable dipping profile. The three groups did not differ with regard to age, gender, body mass index, clinic BP, 48-h BP and heart rate. Left ventricular mass index, interventricular septum thickness, left atrium and aortic root diameters were significantly higher in group II compared with group I (mean +/- SD 108.5 +/- 19.5 versus 99.7 +/- 19.6 g/m, P < 0.05; 9.3 +/- 0.9 versus 9.1 +/- 0.9 mm, P < 0.05; 33.6 +/- 3.6 versus 32.2 +/- 3.7 mm, P < 0.01; 36.9 +/- 4.6 mm versus 35.5 +/- 4.6, P < 0.05, respectively). The smaller differences seen between groups II and III and between groups I and III were not statistically significant. The prevalence of left ventricular hypertrophy (defined as a left ventricular mass index > 134 g/m in men and > 110 g/m in women) was greater in group II (19%) than in group I (6%) (P < 0.05), whereas the differences between groups II and III and between groups I and III did not reach statistical significance. Differences among the three groups in the prevalence of carotid structural alterations (such as carotid plaques or intima-media thickening) were not statistically significant, and microalbuminuria had a similar prevalence in all three groups. CONCLUSIONS: Despite similar clinic and 48-h BP values, never-treated hypertensive patients with a persistent non-dipper pattern showed a significantly greater extent of cardiac structural alterations compared with subjects with a reproducible dipping pattern, but not those with a variable BP nocturnal profile. A non-dipping pattern diagnosed on two concordant ABPM periods instead of a single monitoring therefore represents a clinical trait associated with more pronounced cardiac abnormalities. Finally, in non-dipping middle-aged hypertensives, echocardiography appears to provide a more accurate risk stratification than carotid ultrasonography or microalbuminuria.     

Is It Possible to Manage Hypertension and Evaluate Therapy Without Ambulatory Blood Pressure Monitoring?

In the management of patients with hypertension, blood pressure (BP) has been traditionally measured in the physician's office. The contribution of ambulatory BP monitoring (ABPM) to the management of hypertensive patients has been increasingly recognized through clinical and epidemiological research. Ambulatory BP monitoring can enhance the ability to detect white-coat or masked hypertension, determine the absence of nocturnal dipping status, and evaluate BP control in patients on antihypertensive therapy. Recently, the United Kingdom National Clinical Guideline Centre published guidelines for the clinical management of primary hypertension in adults, recommending the routine use of ABPM to make the initial diagnosis of hypertension. While the advantages of ABPM are apparent from a clinical perspective, its use should be considered in relation to the cost of the equipment, data evaluation, and staff training as well as the possible inconvenience to the patient. In this review, we summarize the clinical importance of ABPM and discuss the current guidelines for establishing the diagnosis of hypertension.     

Is Nocturnal Blood Pressure Reduction the Secret to Reducing the Rate of Progression of Hypertensive Chronic Kidney Disease?

Hypertension is a significant risk factor for cardiovascular and renal disease. Lowering blood pressure (BP) has been shown to reduce the incidence of cardiovascular disease, but randomized trials have not demonstrated a benefit of lowering BP for the progression of renal disease except in secondary analyses in patients with significant proteinuria. Recently, there has been increasing interest in measuring BP outside of the clinic, using both home and ambulatory blood pressure monitoring (ABPM). ABPM has the advantage of measuring BP throughout both the day and night. Elevated nighttime BP and a lack of decline in BP from day to night (nondipping) are more potent risk factors for cardiovascular and renal outcomes than elevated daytime or clinic BP. Studies have shown that it is possible to lower nighttime BP and restore normal dipping with the administration of antihypertensive medications in the evening, known as chronotherapy. Evening administration of antihypertensives not only lowers nighttime BP but also is associated with decreased urinary protein excretion, decreased cardiovascular events, and decreased all-cause mortality. Reducing nighttime BP may slow the progression of chronic kidney disease and may be the key to linking the treatment of hypertension with improved renal outcomes.     

Nocturnal Blood Pressure, Morning Blood Pressure Surge, and Cerebrovascular Events

Cerebrovascular disease is a common cause of death and major cause of disability worldwide. Even in silent cases (e.g., silent cerebral infarction, white matter lesion), cerebrovascular disease can lead to physical and cognitive impairment, thereby substantially reducing the activities of daily living. Accordingly, the earliest possible action to prevent not only symptomatic but also silent cerebrovascular disease has become a major public health challenge. Hypertension is a potent risk factor for both symptomatic and silent cerebrovascular disease. Twenty-four-hour blood pressure (BP) rather than office BP is closely associated with cerebrovascular disease and/or poor physical and cognitive function. In particular, nocturnal BP and morning BP surge have attracted much attention as risk factors for cerebrovascular diseases independently of 24-h BP level. This review is an attempt to summarize some of the evidence on nocturnal BP level or nocturnal BP dipping status, and morning BP surge as potent risk factors for cerebrovascular disease.     

Is the nocturnal fall in blood pressure reduced in essential hypertensive patients with metabolic syndrome?

OBJECTIVE: The aim of this study was to examine whether an impaired reduction in nocturnal blood pressure (BP), defined on the basis of two periods of ambulatory BP monitoring (ABPM), is present in hypertensive patients with metabolic syndrome, as defined by the NCEP criteria. METHODS: 460 grade 1 and 2 untreated essential hypertensives (mean age 45.9 +/- 11.9 years) referred for the first time to our outpatient hospital clinic underwent the following procedures: 1) medical history and physical examination; 2) repeated clinic BP measurements; 3) routine examinations; 4) ABPM over two 24-hour periods within 4 weeks. Metabolic syndrome was defined as at least three of the following alterations: increased waist circumference, increased triglycerides, decreased HDL-cholesterol, increased BP, or high fasting glucose. Nocturnal dipping was defined as a night-time reduction in average SBP and DBP >10% compared to average daytime values. RESULTS: The 135 patients with metabolic syndrome (group I) were similar for age, gender and known duration of hypertension to the 325 patients without it (group II). There were no significant differences between the two groups in average 48-hour, daytime, night-time SBP/DBP values and the percentage nocturnal SBP and DBP decrease (-17.7 / -15.7 vs. -18.4 / -16.2, p = ns). A reproducible nocturnal dipping (decrease in BP >10% from mean daytime in both ABPM periods) and non-dipping profile (decrease in BP < or =10% in both ABPM periods) was found in 74 (54.8%) and 29 (21.4%) in group I and in 169 (52.1%) and 73 (22.4%) in group II, respectively (p = ns); 32 patients (23.7%) in group I and 83 patients (25.5%) in group II had a variable dipping profile (p = ns). CONCLUSIONS: This study shows that no significant difference exists in nocturnal BP patterns, assessed by two ABPMs, in untreated essential hypertensive patients with metabolic syndrome compared to those without it.     

Reproducibility study of nocturnal blood pressure dipping in patients with high cardiovascular risk

It has been shown that in most people there is a physiological reduction in blood pressure during nighttime sleep, it falling by approximately 10% compared to daytime values (dippers). On the other hand, in some people, there is no nighttime reduction (non‐dippers). Various studies have found an association between being a non‐dipper and a higher risk of cardiovascular disease, but few have assessed whether the nocturnal pattern is maintained over time. From the database of the TAHPS study, data were available on 225 patients, each of whom underwent 24‐hour ambulatory blood pressure monitoring (ABPM) on four occasions over a period of 5 months. We studied the reproducibility of the nocturnal BP dipping pattern with mixed linear analysis and also calculated the concordance in the classification of patients as dippers or non‐dippers. The intraclass correlation coefficients between the different ABPM recordings were 0.482 and 0.467 for systolic and diastolic blood pressure, respectively. Two‐thirds (67%) and 70% of the patients classified, respectively, as dippers or non‐dippers based on systolic and diastolic blood pressure readings in the first ABPM recording were found to have the same classification based on the subsequent recordings. We conclude that the reproducibility of nocturnal dipping patterns and concordance of dipper vs non‐dipper status in individual patients is modest and therefore that we should be cautious about recommending treatments or interventions based on these patterns.     

Reproducibility of blood pressure variability, white-coat effect and dipping pattern in untreated, uncomplicated and newly diagnosed essential hypertension

OBJECTIVE: To investigate the reproducibility of blood pressure (BP) variability, white-coat effect (WCE) and nocturnal dipping pattern in untreated patients with uncomplicated essential hypertension using 24-hour ambulatory BP monitoring (ABPM). METHODS: Seventy-five newly diagnosed, untreated essential hypertensive subjects (54 men, 21 women 47.6 +/- 9.3 years) were recruited for the study based on conventional measured BP from a total of 180 patients referred for ABPM. Of these, 65 patients underwent repeated ABPM after 4 weeks observation without treatment. Reproducibility of BP, nocturnal dipping pattern, WCE and BP variability were assessed using different methods. RESULTS: The average 24-hour BP (140.8 +/- 11.9/91.8 +/- 6.4 vs. 140.5 +/- 14.5/90.7 +/- 7.6 mmHg, ns) or PP (49.6 +/- 10.8 vs. 49.8 +/- 9.8 mmHg, ns) did not change, nor did daytime BP or PP. The WCE diminished significantly during the observation period (reduction in SBP WCE delta8.2 +/- 12.5 mmHg, p < 0.0001, in DBP WCE, delta3.3 +/- 9.2 mmHg, p = 0.008 and in PP WCE delta4.8 +/- 11.2 mmHg, p = 0.002). Variability in SBP, DBP and PP decreased consistently and significantly during the observation period. The nocturnal dipping pattern was unchanged in 82% of the patients. In 12% non-dipping pattern was converted to dipping pattern after repeated measurement. CONCLUSION: Average ABPs are highly reproducible in patients with uncomplicated essential hypertension of limited duration. Similarly, nocturnal dipping pattern reproduced satisfactorily. These measures have important clinical applicability. The white-coat effect as well as variability are greatly attenuated during repeated measurements, and these measures may thus be of less utility in clinical practice.     

Ambulatory hypertension in a pediatric cohort of sickle cell disease

Hypertension is an established risk factor for subsequent cardiovascular and renal disease in children as well as adults. Sickle cell disease (SCD) is a genetic disorder associated with chronic hemolytic anemia with the major manifestation of vaso-occlusive crises. Although this disease entity involves most organ systems causing vascular and pulmonary injury, little is known about blood pressure (BP) levels or prevalence of hypertension in children with SCD. A cross-sectional study was conducted on 56 children with SCD (54 with hemoglobin SS disease; 2 with hemoglobin Sβ⁰ thalassemia; 29 females). Study participants underwent 24-hour ambulatory BP monitoring (ABPM). Serum creatinine and cystatin C were obtained to assess estimated glomerular filtration rate with age-based formulas. A random urine sample was obtained to estimate urine osmolality and urine albumin to creatinine ratio. Mean age range was 11.9 (±4.5) years. Seventeen participants (30%) met criteria for hypertension based on ABPM. Of the 17 participants classified with hypertension, three had office hypertension with ambulatory hypertension, and 14 had masked hypertension detected on ABPM. Another 28 participants (50%) had some abnormal ABPM parameters in the form of either prehypertension and/or lack of normal nocturnal dipping status. The prevalence of confirmed hypertension, largely manifest by masked hypertension, is high in children, as young as 6 years of age with SCD. Early identification of hypertension in SCD children can confer benefit as it is an important modifiable risk factor for progression of cardiovascular and renal disease.     

Pulse pressure or dipping pattern: which one is a better cardiovascular risk marker in resistant hypertension?

OBJECTIVE: Nocturnal blood pressure (BP) reduction and ambulatory pulse pressure (PP) are well known prognostic markers obtained from ambulatory BP monitoring (ABPM). The aim of this study is to investigate which one of these ABPM parameters is related to high cardiovascular risk profile in resistant hypertension, based on their associations with target organ damage (TOD). METHODS: Clinical-demographic, laboratory and ABPM variables were recorded in a cross-sectional study involving 907 resistant hypertensive patients. Nocturnal systolic BP reduction and 24-h PP were assessed both as continuous and dichotomized variables (PP at the upper tertile value: 63 mmHg). Statistical analyses included bivariate tests and multivariate logistic regression with each TOD as the dependent variable. RESULTS: Patients with the nondipping pattern and high 24-h PP shared some characteristics: they were older, had higher prevalence of cerebrovascular disease and nephropathy, higher office and 24-h BP levels, increased serum creatinine and microalbuminuria, and higher left ventricular mass index than their counterparts. Additionally, patients with high PP had a greater prevalence of diabetes and other TOD. In multivariate logistic regression, high PP was independently associated with all TODs even after adjustment for sex, age, BMI, cardiovascular risk factors, 24-h mean arterial pressure and antihypertensive treatment, whereas nondipping pattern was only associated with hypertensive nephropathy. Furthermore, PP was more strongly associated with the number of TOD than the nocturnal systolic blood pressure (SBP) fall. CONCLUSIONS: In a large group of resistant hypertensive patients, an increased 24-h PP shows a closer correlation with high cardiovascular risk profile than the nocturnal BP reduction.     

Nocturnal blood pressure in untreated essential hypertensives

AIM. Prevalence, correlates and reproducibility of nocturnal hypertension (NH) as defined by fixed cut-off limits in uncomplicated essential hypertension are poorly defined. Therefore, we assessed such issue in a cohort of 658 untreated hypertensives. METHODS. All subjects underwent procedures including cardiac and carotid ultrasonography, 24-h urine collection for microalbuminuria, ambulatory blood pressure monitoring (ABPM), over two 24-h periods within 4 weeks. NH was defined according to current guidelines (i.e. night-time blood pressure, BP ? 120/70 mmHg) and non-dipping status as a reduction in average systolic (SBP) and diastolic BP (DBP) at night lower than 10% compared with daytime values. RESULTS. A total of 477 subjects showed NH during the first and second ABPM period; 62 subjects had normal nocturnal BP (NN) in both ABPM sessions. Finally, 119 subjects changed their pattern from one ABPM session to the other. Overall, 72.5% of subjects had reproducible NH, 18% variable pattern (VP) and 9.5% reproducible NN. In the same group, figures of reproducible non-dipping, variable dipping and reproducible dipping pattern were 24%, 24% and 52%, respectively. Among NH patients, 56% of whom were dippers, subclinical cardiac organ damage was more pronounced than in their NN counterparts. CONCLUSIONS. In uncomplicated essential hypertensives, NH is a more frequent pattern than non-dipping; NH is associated with organ damage, independently of dipping/non-dipping status. This suggests that options aimed at restoring a blunted nocturnal BP fall may be insufficient to prevent cardiovascular complications unless night-time BP values are fully normalized.     

Ambulatory vs Office Blood Pressure Monitoring in Renal Transplant Recipients

Hypertension is common following renal transplantation and has adverse effects on cardiovascular and graft health. Ambulatory blood pressure monitoring (ABPM) is better at overall blood pressure (BP) assessment and is necessary to diagnose nocturnal hypertension, which is also implicated in poor outcomes. The authors performed a retrospective analysis of 98 renal transplant recipients (RTRs) and compared office BP and ambulatory BP recordings. ABPM revealed discordance between office BP and ambulatory BP in 61% of patients, with 3% caused by white‐coat and 58% caused by masked hypertension (of which 33% were caused by isolated nocturnal hypertension). Overall, mean systolic BP was 3.6 mm Hg (0.5–6.5) and diastolic BP was 7.5 mm Hg (5.7–9.3) higher via ambulatory BP than office BP. This was independent of estimated glomerular filtration rate, proteinuria, transplant time/type, and comorbidities. A total of 42% of patients had their management changed after results from ABPM. ABPM should be routinely offered as part of hypertension management in RTRs.     

Identifying patterns of diurnal blood pressure variation among ELSA‐Brasil participants

Ambulatory blood pressure monitoring (ABPM) is the gold standard method for the diagnosis of hypertension. ABPM provides a set of repeated measurements for blood pressure (BP), usually over 24 h. Traditional approaches characterize diurnal BP variation by single ABPM parameters such as average and standard deviation, regardless of the temporal nature of the data. In this way, information about the pattern of diurnal BP variation and relationship between parameters is lost. The objective of this study was to identify and characterize daily BP patterns considering the set of repeated measures from 24‐h ABPM. A total of 859 adult participants of the Brazilian Longitudinal Study of Adult Health (ELSA‐Brasil) performed a 24‐h ABPM record. Hypertension, sex, age, race/color, education, marital status, smoking, alcohol, physical activity, and BMI were the covariables analyzed. Techniques for longitudinal clustering, multinomial models, and models with mixed effects were used. Three daily BP patterns were identified. Daily BP patterns with high BP presented higher standard deviation and morning surge and lower nocturnal dipping. They showed greater systolic BP variability and faster rise than fall in diastolic BP during sleep. Hypertensive, “pardos,” and men had greater odds to present these patterns. Daily BP patterns with high BP presented the worst profile concerning ABPM parameters associated with cardiovascular risk. The daily BP patterns identified contribute to the characterization of diurnal BP variation.     

Prediabetes is associated with abnormal circadian blood pressure variability

Blood pressure (BP) exhibits a circadian variation characterized by a morning increase, followed by a small postprandial valley and a deeper descent during nocturnal rest. Although abnormal 24-h variability (abnormal circadian variability (ACV)) predicts adverse cardiovascular disease (CVD) outcomes, a 7-day automatic ambulatory BP monitoring (ABPM) and subsequent chronobiologic analysis of the gathered data, permits identification of consistency of any abnormal circadian variation. To test whether normal overweight healthy men and women with prediabetes differed from subjects with normoglycemia in having ACV with a 7-day ABPM. Consent for a 7-day ABPM was obtained from subjects with family history of diabetes mellitus, who were participating in the screening phase for a randomized, double blind, placebo-controlled weight loss trial in prediabetics to prevent progression to diabetes mellitus. The automatic 7-day ABPM device recorded BP and heart rate every 30 min during the day and every 60 min during the night. Normoglycemic and prediabetic subjects matched for age, sex, race, BP, BMI, waist circumference and glycemic control, differed statistically significantly only in their fasting and/or 2-h postprandial serum glucose concentrations. Chronobiologically-interpreted 7-day ABPM uncovered no abnormalities in normoglycemics, whereas prediabetics had a statistically significantly higher incidence of high mean BP (MESOR-hypertension), excessive pulse pressure and/or circadian hyper-amplitude-tension (CHAT) (P<0.001). ACV detected with 7-day ABPM may account for the enhanced CVD risk in prediabetes. These findings provide a basis for larger-scale studies to assess the predictive value of 7-day ABPM over the long term.Journal of Human Hypertension (2008) 22, 627-633; doi:10.1038/jhh.2008.32; published online 15 May 2008.     

Should we use ambulatory blood pressure monitoring to guide therapy?

Blood pressure (BP) measured exclusively in the office setting is no longer acceptable as a sole criterion for diagnosing and treating hypertension. Out-of-office measurements are needed. The limitations of office measurements are principally the result of the small number of readings and the white coat effect. Ambulatory BP monitoring (ABPM) is the gold standard for assessing an individual patient’s risk and hence the need for treatment. Patients who have a high nocturnal BP (nondippers) may be at high risk, and the dipping pattern may be normalized by drug treatment. In addition, it is important to assess that treatment is lowering BP for the full 24 hours (peak and trough effects). However, ABPM is not well suited to the repeated assessments that are needed for the evaluation of the response to treatment. For this, home monitoring is preferred and, by using morning and evening measurements, the effects of treatment on the trough and peak BP can be determined.