Ambulatory Blood Pressure and 10-Year Risk of Cardiovascular and Noncardiovascular Mortality

[Ambulatory blood pressure monitoring for hypertension diagnosis?]

The early and accurate diagnosis of hypertension is essential given its importance in the development of cardiovascular disease. The boundaries between normal blood pressure (BP) and hypertension are arbitrary and based on the benefits of treating exceeding those of not treating. Conventional BP measurement at the clinic only offers information of a particular time and presents multiple biases dependent on inherent variability of BP and measurement technique itself. Multiple studies have demonstrated the prognosis superiority in the development of cardiovascular disease of ambulatory blood pressure monitoring (ABPM), allows detection of white coat hypertension, avoiding overdiagnosis and overtreatment, and the detection of patients with masked hypertension who are at risk of underdetection and undertreatment. ABPM also assess nightime BP and circadian variability, providing additional prognostic value. ABPM is recognized in the diagnosis of hypertension in 2011 British NICE Guidelines, very argued at the 2013 European Society of Hypertension guidelines, and recommended in the US Preventive Services Task Force in 2015, 2016 Canadian Guidelines and the 2016 Spanish Program of Preventive Activities and Health Promotion (PAPPS). Its generalization is likely to be only a matter of time.

Nocturia and increase in nocturnal blood pressure: the Nagahama study

OBJECTIVE

Abnormalities in circadian blood pressure (BP) variation, particularly increase in nocturnal BP, have been reported to be risk factors for cardiovascular disease, although the factors associated with BP abnormalities are not fully understood. This study aimed to clarify possible associations of sleep characteristics, including sleep fragmentation, sleep disordered breathing, and nocturia, with sleep BP by simultaneous multiday measurements.

METHODS

A cross-sectional study evaluated 5959 community participants having home-measured data on nocturnal BP change (sleep BP - awaking BP), sleep characteristics, and sleep disordered breathing. Sleep characteristics including the fragmentation index were assessed using wrist-wearable actigraphy, whereas sleep disordered breathing was assessed by 3% oxygen desaturation index obtained using a finger-type monitor. The number of nocturnal urinations was recorded in a sleep diary.

RESULTS

Mean nocturnal SBP change was -8.5 ± 7.9%. A 3% oxygen desaturation index was associated with the BP change independently of the basic covariates (β = 0.051, P = 0.001), although the association became insignificant (P = 0.196) after adjusting the fragmentation index (β = 0.105, P < 0.001). The association of the fragmentation index was also insignificant (P = 0.153) after adjusting measurement season (middle season: β = 0.163, P < 0.001; summer season: β = 0.249, P < 0.001). In contrast, the frequency of urination showed strong and independent association (β = 0.140, P < 0.001), with smaller nocturnal BP drop in participants with frequent urination.

CONCLUSION

Subjective sleep estimates and frequent nocturnal urination may represent a potential risk for circadian BP abnormalities.

Differences in blood pressure riser pattern in patients with acute heart failure with reduced mid-range and preserved ejection fraction

Aims

Heart failure (HF) is classified into three types according to left ventricular ejection fraction (EF). The effect of blood pressure (BP) on the pathogenesis of each type is assumed to be different. However, the association between the prognosis of each type of HF and abnormal BP variations assessed by ambulatory BP monitoring (ABPM), such as nocturnal hypertension and the riser pattern, remains unclear.

Methods and results

We studied 325 consecutive patients with decompensated HF who were acutely admitted to our hospital and underwent ABPM at discharge. During a mean follow‐up of 30.0 months, 52 cardiovascular and 112 all‐cause deaths occurred. The Cox proportional hazards model showed that the mean values of 24 h, awake, and sleep‐time systolic BP (SBP), and abnormal 24 h ABPM patterns, such as nocturnal hypertension and non‐dipper pattern, were not associated with either all‐cause or cardiovascular mortality in patients with HF with reduced EF (HFrEF), HF with mid‐range EF (HFmrEF), or HF with preserved EF (HFpEF), except for sleep‐time SBP in HFrEF. However, the riser pattern was a significant and independent predictor of all‐cause and cardiovascular deaths in patients with HFpEF (hazard ratio, 2.01; 95% confidence interval, 1.12–3.62; 0.0200; and hazard ratio, 2.48; 95% confidence interval, 1.08–5.90; 0.0332, respectively). Sleep‐time pulse rate was similarly decreased in both the riser and non‐riser groups.

Conclusions

The riser pattern of SBP was associated with an increased risk of adverse outcomes among patients with HFpEF but not HFrEF or HFmrEF.

Comparison of Chronic Hemodialysis Patients under Strict Volume Control with respect to Cardiovascular Disease

BACKGROUND

The objective of this study was to determine the effects of strict volume control and nondipper situation on cardiovascular disease in chronic hemodialysis patients.

METHODS

This study is an observational and cross-sectional study including 62 patients with normotensive chronic hemodialysis using no antihypertensive drugs. A series of measurements including ambulatory blood pressure monitoring, left ventricular mass index by echocardiography, common carotid artery intima-media thickness by ultrasound, and body fluids by bioimpedance analysis were conducted for all subjects.

RESULTS

The patients were divided into two groups as dippers and nondippers according to their ambulatory blood pressure monitoring results. Average 48 h systolic, diastolic, and mean arterial blood pressure and nocturnal systolic, diastolic, and mean arterial blood pressure were significantly different between the dipper and nondipper groups (p<0.05). Before and after dialysis, extracellular fluid/intracellular fluid and extracellular fluid/dry body weight ratios were significantly higher in the nondipper group. Left ventricle mass index and interventricular septum thickness were significantly higher in the nondipper group (p<0.05). Left ventricle ejection fraction was significantly lower and common carotid artery intima-media thickness was higher in the nondipper group with a statistical significance (p<0.05). A two-predictor logistic model was fitted to the data to predict the comparability of dippers and nondippers.

CONCLUSION

According to logistic regression analysis, the odds ratio for daytime diastolic blood pressure indicates that nondippers are 0.45 times more likely to have high blood pressure than dippers in daytime. But in night time, nondippers are about 2.55 times more likely to have high blood pressure comparing to dippers. An important finding of this study is that nondipping pattern is associated with cardiac hypertrophy and lower left ventricle ejection fraction in dialysis of patients with no hypertension. The results also suggest that applying strict volume control to achieve a normal blood pressure alone is not sufficient to reduce the risk of cardiovascular morbidity and mortality if the patients do not have a dipper status of nocturnal blood pressure.

Nondipping Pattern and Cardiovascular and Renal Damage in a Population-Based Study (The STANISLAS Cohort Study)

OBJECTIVE

The attenuation of physiological nocturnal decline of blood pressure (BP)-called nondipper pattern-has previously been reported to be associated with target organ damage in hypertensive subjects. However, this association remains debated and poorly studied in normotensive patients. This study aimed to investigate the association between nondipper pattern and subclinical cardiovascular and renal damage in an initially healthy population-based cohort study.

METHODS

The STANISLAS Cohort is a single-center, familial longitudinal cohort composed of 1,006 families (4,295 subjects) recruited in 1993-1995 for a 5-year periodic health examination. A total of 1,334 subjects from the 4th visit (2011-2016) of the STANISLAS cohort were included. This 4th examination included estimated glomerular filtration rate, albumin/creatinine ratio, pulse wave velocity, central systolic BP, carotid intima-media thickness and distensibility, left ventricular mass index, left ventricular hypertrophy, diastolic dysfunction, and ambulatory blood pressure monitoring (ABPM). Nondipping status was defined as a mean reduction in systolic BP (SBP) or diastolic BP (DBP) lower than 10% during nighttime.

RESULTS

Data were obtained from 798 normotensive subjects (45 ± 14 years, 395 [49%] nondippers, SBP/DBP mmHg 24 hours: 116/71 ± 7/5) and 536 hypertensive patients (56 ± 11 years, 257 [48%] nondippers, SBP/DBP mmHg 24 hours: 127/78 ± 10/7). Mean 24-hour and daytime ABPM measurements were within the normal range, even in hypertensive participants (19% treated). The nondipping pattern was not associated with cardiovascular or renal alterations in this population.

CONCLUSION

In this middle-aged population with an overall 24-hour optimal BP control, the nondipper pattern was not associated with increased cardiovascular or renal damage.

[Position statement on ambulatory blood pressure monitoring (ABPM) by the Spanish Society of Hypertension (2019)]

Conventional blood pressure (BP) measurement in clinical practice is the most used procedure for the diagnosis and treatment of hypertension (HT), but is subject to considerable inaccuracies due to, on the one hand, the inherent variability of the BP itself and, on the other hand biases arising from the measurement technique and conditions, Some studies have demonstrated the prognosis superiority in the development of cardiovascular disease using ambulatory blood pressure monitoring (ABPM). It can also detect "white coat" hypertension, avoiding over-diagnosis and over-treatment in many cases, as well detecting of masked hypertension, avoiding under-detection and under-treatment. ABPM is recognised in the diagnosis and management of HT in most of international guidelines on hypertension. The present document, taking the recommendations of the European Society of Hypertension as a reference, aims to review the more recent evidence on ABPM, and to serve as guidelines for health professionals in their clinical practice and to encourage ABPM use in the diagnosis and follow-up of hypertensive subjects. Requirements, procedure, and clinical indications for using ABPM are provided. An analysis is also made of the main contributions of ABPM in the diagnosis of "white coat" and masked HT phenotypes, short term BP variability patterns, its use in high risk and resistant hypertension, as well as its the role in special population groups like children, pregnancy and elderly. Finally, some aspects about the current situation of the Spanish ABPM Registry and future perspectives in research and potential ABPM generalisation in clinical practice are also discussed.

Non-dipping blood pressure pattern and new-onset diabetes in a 21-year follow-up

Purpose: Non-dipping blood pressure (BP) pattern has been associated with metabolic changes and cardiovascular events. With regard of diabetes, studies are scarce. Our aim was to investigate if there is an association between changes in dipping patterns and incidence of diabetes. Materials and methods: A 24-h ambulatory BP measurement was recorded in addition to other laboratory measurements, and a questionnaire and physical examination were carried out in the baseline study and after 21-year follow-up among a study population (n = 449) consisting of randomly selected middle-aged Finnish females and males without diabetes. Results: 128 (28.5%) developed diabetes during the follow-up. The incidence of new-onset diabetes was the highest, 41.0%, among those subjects who were non-dippers (their systolic BP declined <10% from daytime to nighttime) in the baseline and also in the follow-up study, while the incidence of diabetes was 19.6% in the dipper - dipper (a nighttime decline of systolic BP 10% or more) group (p = 0.003). The difference remained statistically significant after adjustment with age, sex, body mass index, fasting glucose, triglycerides, and insulin levels, smoking status, 24-h mean systolic BP, high-sensitivity C-reactive protein, estimated glomerular filtration and diuretics use. In logistic regression analysis, the non-dipper - non-dippers were at higher risk of diabetes compared with dipper - dipper group (OR = 2.27, 95% CI: 1.13-4.56, p = 0.022). Conclusions: Our prospective study shows that there is an independent association between non-dipping BP pattern and the incidence of diabetes in a 21-year follow-up.

Evaluation of Administration Time and Adherence Rates of Morning vs. Bedtime Dosing of Antihypertensive Medications

Purpose The primary objective of this study was to evaluate the time of day patients administer antihypertensive medications. Secondary objectives were to evaluate medication adherence rates between morning and bedtime dosing and possible barriers to bedtime administration. Methods A single-center, cross-sectional study using a mixed-methods model containing a retrospective chart review and telephone survey was administered to hypertensive patients at a multidisciplinary, private practice clinic. Patients above the age of 18 with a diagnosis of hypertension were eligible for inclusion. The primary endpoint was the number of patients administering one or more antihypertensive medications at bedtime. Secondary endpoints were medication adherence and potential barriers of adherence to bedtime dosing. Results A total of 139 responses were collected. Most patients (75.5%) administered all antihypertensive medications in the morning, with only 24.5% of patients administering at least one antihypertensive medication at bedtime. Adherence was higher for medications administered in the morning compared to medications administered at bedtime, 87.8% and 79.4%, respectively. Limitations to this study include the single-center design and potential for patient recall and reporting bias when using self-reported data. Conclusion Results of this study suggest that the prevalence of bedtime administration of antihypertensive medications is low. Although self-reported adherence rates were higher with morning dosing compared to bedtime dosing, adherence rates for bedtime dosing were still promising. Future studies should be conducted to expand on existing morbidity and mortality evidence as well as prevalence of and adherence to bedtime dosing of antihypertensive medications.

Validation of a wrist-type home nocturnal blood pressure monitor in the sitting and supine position according to the ANSI/AAMI/ISO81060-2:2013 guidelines: Omron HEM-9600T

The purpose of the present study was to evaluate the performance of the Omron HEM-9600T, an automatic wrist-type device for self BP measurement, in the sitting position with the wrist at heart level and supine position according to the ANSI/AAMI/ISO81060-2:2013 guidelines. In the supine position, we evaluated the device under 3 different conditions: using the supine with sideways palm position, the supine with upwards palm position, and the supine with downwards palm position. After 106 subjects were screened and 21 subjects were excluded, the same 85 subjects (38 men [44.7%] and 47 women [55.3%]) were included in the analyses for each position. The average age of the subjects was 54.5 ± 12.2 years (mean ± SD). The mean wrist circumference was 17.0 ± 2.4 cm. The wrist size distribution fulfilled the requirements of the guidelines. The mean differences between reference BPs and HEM-9600T readings were 1.0 ± 6.7/1.4 ± 5.7 mm Hg, 6.6 ± 7.2/5.5 ± 6.0 mm Hg, 4.8 ± 7.2/4.9 ± 5.8 mm Hg, and 2.1 ± 7.2/2.8 ± 6.8 mm Hg for SBP/DBP in the sitting position, supine with sideways palm position, supine with upwards palm position, and supine with downwards palm position, respectively. In conclusion, the Omron HEM-9600T in the sitting position fulfilled the validation criteria of the ANSI/AAMI/ISO81060-2:2013 guidelines. On the other hand, the accuracies of HEM-9600T in the supine position differed depending on the positioning of the palm, with only the downwards palm-position measurement fulfilling both validation criteria of the ANSI/AAMI/ISO81060-2:2013 guidelines.

Association between sex hormones and ambulatory blood pressure

INTRODUCTION

Higher levels of total testosterone and lower levels of sex hormone-binding globulin (SHBG) have been associated with increased blood pressure (BP) in women with an inverse association between total testosterone and BP among men. Fewer studies have examined associations with 24-h ambulatory blood pressure (ABP), blunted nocturnal BP decline or the role of dehydroepiandrosterone sulfate (DHEAS), a precursor to androgens.

METHODS

Baseline blood samples were assayed for 229 normotensive men (≥50 years) and women (≥55 years) participating in the VITamin D and OmegA-3 TriaL. Standardized seated BP (SBP and DBP) and 24-h ABP were measured by trained technicians. Self-reported cardiovascular risk factors and sociodemographic variables were reported on baseline questionnaires. Sex stratified linear regression models adjusted for age, race/ethnicity, BMI, smoking and alcohol estimated the association between each sex hormone and measures of BP and 24-h ABP. Logistic regression used to estimate associations with blunted nocturnal decline (>10% reduction in SBP or DBP during sleeping hours).

RESULTS

Total testosterone and SHBG demonstrated significant inverse correlations with SBP whereas DHEAS was not significantly associated with BP. Among men, in multivariable analyses, each 10% increase in DHEAS was associated with a 0.41 mmHg higher seated DBP (β = 4.29, 95% CI 0.84-7.73) and each 10% increase in total testosterone and SHBG was associated with a 0.54 mmHg (β = -5.65, 95% CI -10.45 to -0.84) and 0.60 mmHg (β = -6.30, 95% CI -11.38 to -1.21) decrease in seated DBP, respectively. No significant associations were observed among women.

CONCLUSION

Among men only, we observed statistically significant inverse cross-sectional associations between total testosterone and SHBG with seated DBP, and a significant positive association with DHEAS levels.

The impact of race on outcomes after carotid endarterectomy in the United States

OBJECTIVE

Black patients undergoing carotid endarterectomy (CEA) in the United States are more often symptomatic at presentation and have more comorbidities compared with white patients. However, the impact of race on outcomes after CEA is largely unknown.

METHODS

We identified CEA patients in the Vascular Quality Initiative registry (2012-2017) and compared them by race (black vs white). All other nonwhite races (891 [1.4%]) and Hispanics (2222 [3.4%]) were excluded. We used multilevel logistic regression to account for differences in demographics and comorbidities. We assessed long-term survival using multivariable Cox regression. The primary outcome was perioperative stroke/death, with long-term survival as a secondary outcome.

RESULTS

We included 57,622 CEA patients; 2909 (5.0%) were black, of whom 983 (34%) were symptomatic. Of the 54,713 white patients, 16,132 (30%) were symptomatic. Black patients, compared with white patients, had a higher vascular disease burden and were less likely to be operated on in a high-volume hospital or by a high-volume surgeon. In addition, black symptomatic patients, compared with white symptomatic patients, were more often operated on <2 weeks after the index neurologic symptom (47% vs 40%; P < .001). Perioperative stroke/death was comparable between black and white patients (symptomatic, 2.8% vs 2.2% [P = .2]; asymptomatic, 1.6% vs 1.3% [P = .2]), as was unadjusted survival at 3 years (93% vs 93%; P = .7). However, after adjustment, black patients did experience better long-term survival compared with white patients (hazard ratio, 0.8; 95% confidence interval, 0.7-0.9; P = .01). On multilevel logistic regression, race was not associated with perioperative stroke/death (odds ratio, 1.0; 95% confidence interval, 0.8-1.3; P = .98).

CONCLUSIONS

Despite the greater prevalence of vascular risk factors in black patients and racial inequalities in surgical treatment, rates of perioperative stroke/death and unadjusted survival were similar between white and black patients. Moreover, black patients experienced better adjusted long-term survival after CEA.

Understanding short-term blood-pressure-variability phenotypes: from concept to clinical practice

Clinic blood pressure (BP) is recognized as the gold standard for the screening, diagnosis, and management of hypertension. However, optimal diagnosis and successful management of hypertension cannot be achieved exclusively by a handful of conventionally acquired BP readings. It is critical to estimate the magnitude of BP variability by estimating and quantifying each individual patient's specific BP variations. Short-term BP variability or exaggerated circadian BP variations that occur within a day are associated with increased cardiovascular events, mortality and target-organ damage. Popular concepts of BP variability, including "white-coat hypertension" and "masked hypertension", are well recognized in clinical practice. However, nocturnal hypertension, morning surge, and morning hypertension are also important phenotypes of short-term BP variability that warrant attention, especially in the primary-care setting. In this review, we try to theorize and explain these phenotypes to ensure they are better understood and recognized in day-to-day clinical practice.

Effect of renal denervation on coronary flow reserve in patients with resistant hypertension

Renal denervation (RDN) is a potential modality in the treatment of patients with resistant hypertension (RH) and has shown beneficial effect on a variety of cardiovascular surrogate markers. Coronary flow reserve, as assessed by transthoracic Doppler echocardiography (TDE-CFR) is impaired in patients with hypertension and is an independent predictor of cardiac morbidity. However, data on the effect of RDN on TDE-CFR are scarce. The main objective of this study was to assess the effect of RDN on TDE-CFR. Twenty-six consecutive patients with RH (9 female and 17 male; mean age 62 ± 8 years; mean number of antihypertensive drugs 4·2 ± 1·6) underwent bilateral RDN. CFR was assessed at baseline and 6 months after intervention. Mean flow velocity was measured in the left anterior descending artery by transthoracic Doppler echocardiography at baseline and during adenosine infusion (TDE-CFR). Systolic office blood pressure was reduced at follow-up (174 ± 24 versus 162 ± 27 mmHG; P = 0·01). Mean systolic ambulatory blood pressure decreased from 151 ± 21 to 147 ± 18 (P = 0·17). TDE-CFR remained unchanged 6 months after intervention (2·7 ± 0·6 versus 2·7 ± 0·7; P = 0·67). In conclusion, renal denervation was not associated with any changes in regard to coronary flow reserve at 6-month follow-up.

Experimental Weight Gain Increases Ambulatory Blood Pressure in Healthy Subjects: Implications of Visceral Fat Accumulation

OBJECTIVE

To examine whether experimentally induced weight gain raises ambulatory blood pressure (BP) in healthy subjects and identify any relationship between changes in BP and changes in regional fat distribution.

PATIENTS AND METHODS

Twenty-six normal weight subjects were randomized to 8 weeks of weight gain through overfeeding (n=16; age, 30.4±6.6 years) or to weight maintenance (controls; n=10; age, 27.1±7.7 years) between July 2004 and August 2010. Measures of body composition via dual energy X-ray absorptiometry and computed tomography, circulating biomarkers, and 24-hour ambulatory BP were obtained at baseline and after the 8-week experimental phase.

RESULTS

Overfeeding resulted in 3.7 kg (95% CI, 2.9-4.5) increase in body weight in weight gainers, with increments in total (46.2 cm²; 95% CI, 27.6-64.9), visceral (13.8 cm²; 95% CI, 5.8-21.9), and subcutaneous fat (32.4 cm²; 95% CI, 13.5-51.3). No changes occurred in the maintenance group. Increases in 24-hour systolic BP (4 mm Hg; 95% CI, 1.6-6.3), mean BP (1.7 mm Hg; 95% CI, 0.3-3.3), and pulse pressure (2.8 mm Hg; 95% CI, 1.1-4.4) were evident after weight gain in the experimental group, whereas BP remained unchanged in controls. Changes in mean BP correlated only with changes in visceral fat (ρ=0.45; P=.02), but not with changes in other body composition measures.

CONCLUSION

Modest weight gain causes elevation in 24-hour BP in healthy subjects. The association between increased BP and abdominal visceral fat accumulation suggests that visceral deposition of adipose tissue may contribute specifically to the enhanced risk of hypertension associated with weight gain.

Circadian regulation of kidney function: finding a role for Bmal1

Mounting evidence suggests that there is an internal molecular "clock" within the kidney to help maintain normal renal function. Disturbance of the kidney circadian rhythm may pose a threat to water and electrolyte homeostasis and blood pressure regulation, among many other problems. The identification of circadian genes facilitated a more comprehensive appreciation of the importance of "keeping the body on time"; however, our knowledge is very limited with regard to how circadian genes regulate kidney function. In this brief review, we summarize recent progress in circadian control of renal physiology, with a particular focus on aryl hydrocarbon receptor nuclear translocator-like protein (Arntl1; also called Bmal1).

Relationship between Clinic and Ambulatory Blood-Pressure Measurements and Mortality

BACKGROUND

Evidence for the influence of ambulatory blood pressure on prognosis derives mainly from population-based studies and a few relatively small clinical investigations. This study examined the associations of blood pressure measured in the clinic (clinic blood pressure) and 24-hour ambulatory blood pressure with all-cause and cardiovascular mortality in a large cohort of patients in primary care.

METHODS

We analyzed data from a registry-based, multicenter, national cohort that included 63,910 adults recruited from 2004 through 2014 in Spain. Clinic and 24-hour ambulatory blood-pressure data were examined in the following categories: sustained hypertension (elevated clinic and elevated 24-hour ambulatory blood pressure), "white-coat" hypertension (elevated clinic and normal 24-hour ambulatory blood pressure), masked hypertension (normal clinic and elevated 24-hour ambulatory blood pressure), and normotension (normal clinic and normal 24-hour ambulatory blood pressure). Analyses were conducted with Cox regression models, adjusted for clinic and 24-hour ambulatory blood pressures and for confounders.

RESULTS

During a median follow-up of 4.7 years, 3808 patients died from any cause, and 1295 of these patients died from cardiovascular causes. In a model that included both 24-hour and clinic measurements, 24-hour systolic pressure was more strongly associated with all-cause mortality (hazard ratio, 1.58 per 1-SD increase in pressure; 95% confidence interval [CI], 1.56 to 1.60, after adjustment for clinic blood pressure) than the clinic systolic pressure (hazard ratio, 1.02; 95% CI, 1.00 to 1.04, after adjustment for 24-hour blood pressure). Corresponding hazard ratios per 1-SD increase in pressure were 1.55 (95% CI, 1.53 to 1.57, after adjustment for clinic and daytime blood pressures) for nighttime ambulatory systolic pressure and 1.54 (95% CI, 1.52 to 1.56, after adjustment for clinic and nighttime blood pressures) for daytime ambulatory systolic pressure. These relationships were consistent across subgroups of age, sex, and status with respect to obesity, diabetes, cardiovascular disease, and antihypertensive treatment. Masked hypertension was more strongly associated with all-cause mortality (hazard ratio, 2.83; 95% CI, 2.12 to 3.79) than sustained hypertension (hazard ratio, 1.80; 95% CI, 1.41 to 2.31) or white-coat hypertension (hazard ratio, 1.79; 95% CI, 1.38 to 2.32). Results for cardiovascular mortality were similar to those for all-cause mortality.

CONCLUSIONS

Ambulatory blood-pressure measurements were a stronger predictor of all-cause and cardiovascular mortality than clinic blood-pressure measurements. White-coat hypertension was not benign, and masked hypertension was associated with a greater risk of death than sustained hypertension. (Funded by the Spanish Society of Hypertension and others.).

Twenty-Four-Hour Ambulatory Blood Pressure versus Clinic Blood Pressure Measurements and Risk of Adverse Outcomes in Children with CKD

BACKGROUND

and objectives Our objective was to determine whether clinic BPs (taken at either a single visit or two sequential visits) are inferior to ambulatory BPs in their ability to discriminate risk of adverse outcomes in children with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We included 513 participants of the CKD in Children Study who had clinic BPs and 24-hour ambulatory BP monitoring performed during similar timeframes. Predictors of interest were systolic BPs taken at a single visit or two repeated visits within a 1-year period compared with mean wake and sleep systolic ambulatory BPs. Outcomes were left ventricular hypertrophy and ESKD. We determined the ability for each BP parameter to provide risk discrimination using c statistics.

RESULTS

During mean follow-up of 3.5 years, 123 participants developed ESKD. In cross-sectional unadjusted analysis, every 0.1 increase in systolic BP index was associated with a 2.0 times higher odds of left ventricular hypertrophy (95% confidence interval, 1.5 to 2.8) by clinic BPs versus 1.8 times higher odds (95% confidence interval, 1.3 to 2.4) by ambulatory wake BP. The c statistic was highest for clinic BP (c=0.65; 95% confidence interval, 0.58 to 0.73) but similar to ambulatory wake BP (c=0.64; 95% confidence interval, 0.57 to 0.71) for the discrimination of left ventricular hypertrophy. In longitudinal unadjusted analysis, every 0.1 increase in systolic BP index was associated with a higher risk of ESKD using repeated clinic (hazard ratio, 1.5; 95% confidence interval, 1.3 to 1.8) versus ambulatory wake BP (hazard ratio, 1.6; 95% confidence interval, 1.3 to 2.0). Unadjusted c statistics were the same for wake (c=0.61; 95% confidence interval, 0.56 to 0.67) and clinic systolic BPs (c=0.61; 95% confidence interval, 0.55 to 0.66) for discriminating risk of ESKD.

CONCLUSIONS

Clinic BPs taken in a protocol-driven setting are not consistently inferior to ambulatory BP in the discrimination of BP-related adverse outcomes in children with CKD.

Resistant Hypertension: Mechanisms and Treatment

PURPOSE OF REVIEW

Emerging evidence suggests that multiple mechanisms may be responsible for the development of treatment-resistant hypertension (TRH). This review aims to summarize recent data on potential mechanisms of resistance and discuss current pharmacotherapeutic options available in the management of TRH.

RECENT FINDINGS

Excess sodium and fluid retention, increased activation of the renin-angiotensin-aldosterone system, and heightened activity of the sympathetic nervous system appear to play an important role in development of TRH. Emerging evidence also suggests a role for arterial stiffness and, potentially, gut dysbiosis. Therapeutic approaches for TRH should include diuretic optimization and the addition of aldosterone antagonists as the preferred fourth agent in most patients. Further therapeutic approaches may be guided by the suspected underlying mechanism of TRH in conjunction with other patient-specific factors. The pathophysiology of TRH is multifaceted; however, increasing evidence supports several mechanisms that may be targeted to improve blood pressure control among patients with TRH. Further studies are needed to determine whether such approaches may be more effective than usual care.

Black patients present with more severe vascular disease and a greater burden of risk factors than white patients at time of major vascular intervention

BACKGROUND

Although many studies have demonstrated racial disparities after major vascular surgery, few have identified the reasons for these disparities, and those that did often lacked clinical granularity. Therefore, our aim was to evaluate differences in initial vascular intervention between black and white patients.

METHODS

We identified black and white patients' initial carotid, abdominal aortic aneurysm (AAA), and infrainguinal peripheral artery disease (PAD) interventions in the Vascular Quality Initiative (VQI) registry from 2009 to 2014. We excluded nonblack or nonwhite patients as well as those with Hispanic ethnicity, asymptomatic PAD, or a history of prior ipsilateral interventions. We compared baseline characteristics and disease severity at time of intervention on a national and regional level.

RESULTS

We identified 76,372 patients (9% black), including 35,265 carotid (5% black), 17,346 AAA (5% black), and 23,761 PAD interventions (18% black). For all operations, black patients were younger, more likely female, and had more insulin-dependent diabetes, hypertension, congestive heart failure, renal dysfunction, and dialysis dependence. Black patients were less likely to be on a statin before AAA (62% vs 69%; P < .001) or PAD intervention (61% vs 67%; P < .001) and also less likely to be discharged on an antiplatelet and statin regimen after these procedures (AAA, 60% vs 64% [P = .01]; PAD, 64% vs 67% [P < .001]). Black patients presented with more severe disease, including higher proportions of symptomatic carotid disease (36% vs 31%; P < .001), symptomatic or ruptured AAA (27% vs 16%; P < .001), and chronic limb-threatening ischemia (73% vs 62%; P < .001). Black patients more often presented with concurrent iliac artery aneurysms at the time of AAA repair (elective open AAA repair, 46% vs 26% [P < .001]; elective endovascular aneurysm repair, 38% vs 23% [P < .001]).

CONCLUSIONS

Black patients present with more advanced disease at the time of initial major vascular operation. Efforts to control risk factors, identify and treat arterial disease in a timely fashion, and optimize medical management among black patients may provide opportunity to improve current disparities.

The J-curve between Diastolic Blood Pressure and Risk of All-cause and Cardiovascular Death

BACKGROUND AND OBJECTIVES

The J-curve phenomenon between diastolic blood pressure (DBP) and mortality has been reported repeatedly in treated patients. However, the baseline risk of low DBP has not been fully explored. This study was to examine the relationship between DBP and risk of mortality from all-cause, atherosclerotic vascular diseases (ASCVD), and ischemic heart disease (IHD) using a prospective cohort of general population.

METHODS

We analyzed 1,234,435 participants of the Korean Cancer Prevention Study cohort (789,255 men, 30-95 years of age) who had a medical evaluation from 1992 to 1995 using Cox proportional hazards models.

RESULTS

A total of 22.5 million person-years were followed up (mean age 46.6 years, deaths 193,903 cases). The hazard ratios of mortality from all-cause and ASCVD, among those with DBP <60 mmHg compared to 70-79 mmHg were 1.23 (95% confidence interval [CI], 1.16-1.30) and 1.37 (95% CI, 1.20-1.57), respectively, after adjustment for multivariable including systolic blood pressure. Increased risks of all-cause death in the lowest DBP category group were maintained in men or women, 30-59 or ≥60 years of age, smoker or non-smoker and diabetes mellitus (DM) or non-DM subgroups. The risk in DBP 60-69 mmHg groups increased in several subgroups. However, the risk for ASCVD death in 30-59 years and DM group, and risk for IHD death in most subgroups except for elderly (≥60 years) decreased.

CONCLUSION

A J-curve relationship between low DBP and all-cause death was found consistently. The baseline risk in the general population may be considered for risk assessment, particularly in case of interventions that lower DBP below 60 mmHg.

Relationship between body mass and ambulatory blood pressure: comparison with office blood pressure measurement and effect of treatment

Epidemiologic studies assessing the relationship between blood pressure (BP), body mass and cardiovascular events have primarily been based on office BP measurements, and few data are available in the elderly. The aim of the present study was to evaluate the relationship between body mass index (BMI) and BP values obtained by ambulatory blood pressure monitoring (ABPM) as compared to office BP measurements, and the effect of anti-hypertensive treatment on the relationship. The study population consisted of 813 subjects participating in the Cardiovascular Abnormalities and Brain Lesions (CABL) study who underwent 24-hour ABPM. Office BP (mean of 2 measurements) was found to be associated with increasing BMI, for both SBP (p≤0.05) and DBP (p≤0.001). In contrast, there was no association seen of increasing BMI with ABPM parameters in the overall cohort, even after adjusting for age and gender. However, among subjects not on anti-hypertensive treatment, office SBP and DBP measurements were significantly correlated with increasing BMI (p≤0.01) as were daytime SBP and 24-hour SBP, although with a smaller spread across BMI subgroups compared with office readings. In treated hypertensives, there was only a trend toward increasing office DBP and increasing DBP variability with higher BMI. Our results suggest that body mass may be a less significant influence on BP values in the elderly when ABPM rather than office measurements are considered, particularly in patients receiving anti-hypertensive treatment.

The association between home vs. ambulatory night-time blood pressure and end-organ damage in the general population

OBJECTIVE

The aim of this study was to test the agreement between night-time home and night-time ambulatory blood pressure (BP) and to compare their associations with hypertensive end-organ damage for the first time in the general population.

METHODS

A population sample of 248 participants underwent measurements for night-time home BP (three measurements on two nights with a timer-equipped home device), night-time ambulatory BP, pulse wave velocity (PWV), carotid intima-media thickness (IMT) and echocardiographic left ventricular mass index (LVMI).

RESULTS

No significant or systematic differences were observed between mean night-time ambulatory and home BPs (systolic/diastolic difference: 0.7 ± 7.6/0.2 ± 6.0 mmHg, P = 0.16/0.64). All night-time home and ambulatory BPs were positively correlated with PWV, IMT and LVMI (P < 0.01 for all). No significant differences in Pearson's correlations between end-organ damage and night-time home or ambulatory BP were observed (P ≥ 0.11 for all comparisons using Dunn and Clark's Z), except for a slightly stronger correlation between PWV and ambulatory SBP than for home SBP (r = 0.57 vs. 0.50, P = 0.03). The adjusted R of all multivariable-adjusted models for PWV, IMT or LVMI that included night-time home or ambulatory SBP/DBP were within 2/1%.

CONCLUSION

Our study demonstrates that night-time home and ambulatory measurements produce similar BP values that have comparable associations with end-organ damage in the general population even when a clinically feasible measurement protocol is used for measuring night-time home BP. In the future, night-time home BP measurement may offer a feasible and easily accessible alternative to ambulatory monitoring for the measurement of night-time BP.

Association of blood pressure in the supine position with target organ damage in subjects over 60 years old

Objective Toexplore the correlation between blood pressure in the supine position and target organ damage in subjects over 60 years of age. Methods In 2444 individuals, we investigated the association of systolic blood pressure (SBP) in the supine position with the target organ damage indices microalbuminuria (ALBU), brachial-ankle pulse wave velocity (baPWV), and carotid intima-media thickness (IMT). Supine hypertension (SH) is defined as systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg. Subjects were assigned to either the SH group (1275 cases) or the non-SH group (1169 cases). Results The levels of ALBU, baPWV, and IMT, as well as the percentage of participants with ALBU > 30 mg/L, baPWV ≥ 1400 cm/s, and IMT ≥ 1 mm, were significantly higher in the SH group than in the non-SH group. Multivariate logistic regression analysis showed that SH was an independent risk factor for baPWV and IMT, but the relationship with ALBU was not statistically significant after correction for confounding factors. Conclusions SH is a risk factor for target organ damage, as expressed by the indices baPWV and IMT. The association of SH with kidney damage requires further study.

Novel Triggered Nocturnal Blood Pressure Monitoring for Sleep Apnea Syndrome: Distribution and Reproducibility of Hypoxia-Triggered Nocturnal Blood Pressure Measurements

Obstructive sleep apnea (OSA) causes blood pressure (BP) surges during sleep, which may lead to increased sleep-onset cardiovascular events. The authors recently developed a triggered nocturnal BP monitoring system that initiates BP measurements when oxygen desaturation falls below a variable threshold. The distribution and reproducibility of hypoxia-triggered nocturnal BP parameters compared with those of fixed-interval nocturnal BP parameters for two consecutive nights in 147 OSA patients (mean age 59.4 years, 86.4% men) were evaluated. The mean and distribution (standard deviation [SD]) of the hypoxia-peak systolic BP (SBP) were significantly greater than that of the mean nocturnal SBP (mean±SD: 148.8±20.5 vs 123.4±14.2 mm Hg, P<.001). The repeatability coefficient (expressed as %MV) of hypoxia-peak SBP between night 1 and night 2 was comparable to that of mean nocturnal SBP (43% vs 32%). In conclusion, hypoxia-peak nocturnal BP was much higher than mean nocturnal BP, and it was as reproducible as mean nocturnal BP.

Exaggerated exercise blood pressure response in middle-aged men as a predictor of future blood pressure: a 10-year follow-up

OBJECTIVE

The prognostic value of an exaggerated exercise systolic blood pressure response (EESBPR) remains controversial. This study was designed to assess whether an EESBPR is associated with the predictor of future blood pressure.

METHODS

From an initial population of 1,534 male-subjects with normal BP or no medication who underwent ergometric exercise, 733 subjects (mean age: 41 years old) at baseline to follow-up BP after an average of 10 years were selected. A 12-min exercise tolerance test with three phases of estimated load from predictive maximum oxygen intake was performed at baseline, and exercise BP was measured.

RESULTS

Exercise BP response was classified by three group: Low group (G) (exercise SBP < 180 mmHg), Middle G (exercise BP:180-199 mmHg), High G (exercise BP:200 mmHg ≦). BP after 10 years in Low G was 123 ± 12/79 ± 7 mmHg, in Middle G:127 ± 13/81 ± 8 mmHg, in High G :134 ± 15/84 ± 10 mmHg. Compared with in Low G, BP after 10 years in High G significantly increased (p < 0.05). Multiple regression analysis was carried out to clarify the relationship of exercise SBP at baseline to BP after 10 years. In multivariate-adjusted models, the relationship of SBP at follow-up was stronger to exercise SBP (β = 0.271, P < 0.001) than to resting SBP (β = 0.148, P < 0.001). Maximum oxygen intake (β = -0.193, P = 0.003) and resting SBP correlated with SBP after 10 years.

CONCLUSIONS

In middle-aged men, exercise SBP would be a stronger predictor of future SBP, DBP rather than BP at rest. In optimal of classification of BP (SBP < 120 mmHg), exercise BP response was clearly associated with BP after 10 years.

Ambulatory blood pressure variability: a conceptual review

Ambulatory blood pressure (ABP) has long been recognized by researchers as the gold standard of blood pressure (BP) measurement. Researchers and clinicians typically rely on the mean measure of ABP; however, there is considerable variability in the beat-to-beat BP. Although often ignored, this variability has been found to be an independent predictor of cardiovascular disease and mortality. The aim of this paper is to provide a conceptual review of ABP variability (ABPV) focusing on the following: associations between ABPV and health, whether ABPV is reliable, how to calculate ABPV, predictors of ABPV, and treatments for ABPV. Two future directions are discussed involving better understanding ABPV by momentary assessments and improving knowledge of the underlying physiology that explains ABPV. The results of this review suggest that the unique characteristics of ABPV provide insight into the role of BP variability in hypertension and subsequent cardiovascular illness.

Association Between High and Very High Albuminuria and Nighttime Blood Pressure: Influence of Diabetes and Chronic Kidney Disease

OBJECTIVE

Nighttime blood pressure (BP) and albuminuria are two important and independent predictors of cardiovascular morbidity and mortality. Here, we examined the quantitative differences in nighttime systolic BP (SBP) across albuminuria levels in patients with and without diabetes and chronic kidney disease.

RESEARCH DESIGN AND METHODS

A total of 16,546 patients from the Spanish Ambulatory Blood Pressure Monitoring Registry cohort (mean age 59.6 years, 54.9% men) were analyzed. Patients were classified according to estimated glomerular filtration rate (eGFR), as ≥60 or <60 mL/min/1.73 m(2) (low eGFR), and urine albumin-to-creatinine ratio, as normoalbuminuria (<30 mg/g), high albuminuria (30-300 mg/g), or very high albuminuria (>300 mg/g). Office and 24-h BP were determined with standardized methods and conditions.

RESULTS

High albuminuria was associated with a statistically significant and clinically substantial higher nighttime SBP (6.8 mmHg higher than with normoalbuminuria, P < 0.001). This association was particularly striking at very high albuminuria among patients with diabetes and low eGFR (16.5 mmHg, P < 0.001). Generalized linear models showed that after full adjustment for demographic, lifestyles, and clinical characteristics, nighttime SBP was 4.8 mmHg higher in patients with high albuminuria than in those with normoalbuminuria (P < 0.001), and patients with very high albuminuria had a 6.1 mmHg greater nighttime SBP than those with high albuminuria (P < 0.001). These differences were 3.8 and 3.1 mmHg, respectively, among patients without diabetes, and 6.5 and 8 mmHg among patients with diabetes (P < 0.001).

CONCLUSIONS

Albuminuria in hypertensive patients is accompanied by quantitatively striking higher nighttime SBP, particularly in those with diabetes with very high albuminuria and low eGFR.

Ambulatory Blood Pressure Monitoring: Five Decades of More Light and Less Shadows

Casual blood pressure measurements have been extensively questioned over the last five decades. A significant percentage of patients have different blood pressure readings when examined in the office or outside it. For this reason, a change in the paradigm of the best manner to assess blood pressure has been observed. The method that has been most widely used is the Ambulatory Blood Pressure Monitoring - ABPM. The method allows recording blood pressure measures in 24 hours and evaluating various parameters such as mean BP, pressure loads, areas under the curve, variations between daytime and nighttime, pulse pressure variability etc. Blood pressure measurements obtained by ABPM are better correlated, for example, with the risks of hypertension. The main indications for ABPM are: suspected white coat hypertension and masked hypertension, evaluation of the efficacy of the antihypertensive therapy in 24 hours, and evaluation of symptoms. There is increasing evidence that the use of ABPM has contributed to the assessment of blood pressure behaviors, establishment of diagnoses, prognosis and the efficacy of antihypertensive therapy. There is no doubt that the study of 24-hour blood pressure behavior and its variations by ABPM has brought more light and less darkness to the field, which justifies the title of this review.

Sleep-time ambulatory blood pressure as a prognostic marker of vascular and other risks and therapeutic target for prevention by hypertension chronotherapy: Rationale and design of the Hygia Project

This article describes the rationale, objectives, design and conduct of the ambulatory blood pressure monitoring (ABPM)-based Hygia Project. Given the substantial evidence of the significantly better prognostic value of ABPM compared to clinic BP measurements, several international guidelines now propose ABPM as a requirement to confirm the office diagnosis of hypertension. Nonetheless, all previous ABPM outcome investigations, except the Monitorización Ambulatoria para Predicción de Eventos Cardiovasculares study (MAPEC) study, relied upon only a single, low-reproducible 24 h ABPM assessment per participant done at study inclusion, thus precluding the opportunity to explore the potential reduction in cardiovascular disease (CVD) risk associated with modification of prognostic ABPM-derived parameters by hypertension therapy. The findings of the single-center MAPEC study, based upon periodic systematic 48 h ABPM evaluation of all participants during a median follow-up of 5.6 years, constitute the first proof-of-concept evidence that the progressive reduction of the asleep systolic blood pressure (SBP) mean and correction of the sleep-time relative SBP decline toward the normal dipper BP profile, most efficiently accomplished by a bedtime hypertension treatment strategy, best attenuates the risk of CVD, stroke and development of new-onset diabetes. The Hygia Project, primarily designed to extend the use of ABPM in primary care as a requirement for diagnosis of hypertension, evaluation of response to treatment and individualized assessment of CVD and other risks, is a research network presently composed of 40 clinical sites and 292 investigators. Its main objectives are to (i) investigate whether specific treatment-induced changes in ABPM-derived parameters reduce risk of CVD events, stroke, new-onset diabetes and/or development of chronic kidney disease (CKD); and (ii) test the hypothesis that bedtime chronotherapy entailing the entire daily dose of ≥1 conventional hypertension medications exerts better ambulatory BP control and CVD, metabolic and renal risk reduction than all such medications ingested in the morning upon awakening. Between 2007 and 2015, investigators recruited 18 078 persons [9769 men/8309 women, 59.1 ± 14.3 years of age (mean ± SD)], including 15 764 with hypertension according to ABPM criteria as participants in the prospective randomized chronotherapy trial. The initial evaluation includes 48 h ABPM, detailed medical history and screening laboratory blood and urine tests. The same evaluation procedure is scheduled annually, or more frequently when treatment adjustment is required for proper ambulatory BP control, targeting a median follow-up of >5 years. The primary CVD outcome end point is the composite of CVD death, myocardial infarction, coronary revascularization, heart failure, ischemic stroke and hemorrhagic stroke. The independent Hygia Project Events Committee periodically evaluates blinded clinical reports to ascertain and certify every documented event. Beyond the potential findings resulting from testing the main hypotheses, the Hygia Project has already demonstrated, as proof of concept, that the routine diagnosis of hypertension and individualized assessment of CVD and other risks by ABPM, as currently recommended, is fully viable in the primary care setting, where most people with either hypertension, dyslipidemia, type 2 diabetes or CKD receive routine medical attention.

Office and ambulatory blood pressure control in hypertensive patients treated with different two-drug and three-drug combinations

There is scarce information regarding ambulatory blood pressure (BP) achieved in daily practice with a wide range of antihypertensive drug combinations. We looked for differences in office and ambulatory BP among major drug combinations of two and three antihypertensive agents from a different drugs class. A total of 17187 patients treated with six types of two-drug combinations and 9724 treated with six types of three-drug combinations from the Spanish ABPM Registry were analyzed. We compared achieved office and ambulatory BP, as well as office (< 140/90 mmHg) and ambulatory (24-hour BP < 130/80; day BP < 135/85, and night BP < 120/70 mmHg) BP control among groups. The combination of renin-angiotensin system (RAS) blockers with diuretics and the triple combination of RAS blockers with diuretics and calcium channel blockers (CCB) were associated with lower values of 24-hour, daytime and nighttime BP, as well as more pronounced nocturnal BP dip. Compared with such combinations (reference), other double combinations had lower rates of ambulatory BP control. Moreover, triple combinations containing alpha blockers also had lower rates of ambulatory BP control. We conclude that even with similar office BP control, differences exist among antihypertensive two-drug and three-drug combinations with respect to ambulatory BP control achieved during treatment, with RAS blockers/diuretics and RAS blockers/CCBs/diuretics obtaining better control rates. This can help physicians choose among drug combinations in order to obtain further ambulatory BP reductions.

Prehypertension in adolescents with cardiovascular risk: a comparison between type 1 diabetic patients and overweight subjects

BACKGROUND

Adolescents with type 1 diabetes and obesity present higher cardiovascular risk and ambulatory blood pressure measurements (ABPM) has been shown to predict vascular events, especially by identifying the nondipper status. The aim of our observational cross-sectional study conducted in adolescents with type 1 diabetes, overweight subjects and healthy controls was to assess mean blood pressure parameters to identify subclinical cardiovascular risk.

METHODS

The study included adolescents patients with type 1 diabetes followed in our Pediatric Department in University of Catania between January 2011 and 2013. A total of 60 patients were enrolled, and 48 (32 male and 16 female) completed the study. For each subject we performed systolic and diastolic Ambulatory Blood Pressure Measurements (ABPM) during wakefulness and sleep recording blood pressure every 30 min for 24 h with the Tonoport V/2 GE CardioSoft V6.51 device. We compared the data of patients with those of overweight subjects and healthy controls.

RESULTS

ABPM revealed no significant difference between type 1 diabetic patients and overweight subjects in 24 h Systolic, 24 h Diastolic, Day-time Systolic, Night-time systolic and Day-time Diastolic blood pressure values but significantly different values in Night-time Diastolic blood pressure values (p < 0.001). We found significant differences between type 1 diabetic patients and healthy controls in all 24 h Systolic (p < 0.001), 24 h Diastolic (p < 0.01), Day-time Systolic (p < 0.01), Night-time Systolic (p < 0.001), Day-time Diastolic (p < 0.05) and Night-time Diastolic (p < 0.001) blood pressure values. We detected hypertension in 12/48 (25%) type 1 diabetic patients and in 10/48 overweight subjects (p = 0.62; OR 1.2; CI 0.48-3.29), whereas no-one of healthy controls presented hypertension (p < 0.001). We observed nondipper pattern in 40/48 (83.3%) type 1 diabetic patients, in 33/48 (68.8%) overweight subjects (p = 0.094; OR 2.27; CI 0.85-6.01), and in 16/48 (33.3%) of healthy controls (p < 0.001; OR 10; CI 3.79-26.3).

CONCLUSIONS

ABPM studies might help to define a subset of patients at increased risk for the development of hypertension. In evaluating blood pressure in type 1 diabetes and overweight subjects, ABPM should be used since a reduced dipping can indicate incipient hypertension.

Does sympathetic overactivation feature all hypertensives? Differences of sympathovagal balance according to night/day blood pressure ratio in patients with essential hypertension

When evaluating the 'night/day BP ratio', both hypertensives and normotensives can be arbitrarily classified into four groups: extreme dippers (ratio ⩽0.8), dippers (0.8<ratio ⩽0.9), mild dippers (0.9<ratio⩽1.0) and reverse dippers (ratio ⩾1.0). Reverse and mild dipper hypertensives have poorer prognoses compared with the physiological dipper profile, but the prognostic relevance of the extreme dipper profile remains uncertain. The evaluation of heart rate variability (HRV), obtained by 24-h Holter ECG monitoring, is the most frequently used noninvasive form of assessment of the activity of the autonomic nervous system. Reverse and mild dipper hypertensives have reduced HRV, indicating an overactivation of the sympathetic nervous system (SNS); however, the HRV behavior in extreme dippers is still controversial. The goal of this study was to compare HRV indexes of extreme vs. reverse dipper essential hypertensives measured on the basis of time domains. We enrolled 125 hypertensive subjects, divided in 4 quartiles according to day/night blood pressure (BP) ratios. The upper and lower quartiles (31 subjects per quartile) were compared; 30 normotensive subjects were enrolled as a control group. Time domain HRV parameters of the three groups revealed a higher degree of sympathetic activation in the lower quartile (reverse dipper) vs. the upper quartile (extreme) and normotensive controls. HRV parameters related to parasympathetic tone did not show any significant variations among the three groups. Contrary to common belief, not all hypertensives have SNS overactivation.

Sleep-time BP: prognostic marker of type 2 diabetes and therapeutic target for prevention

AIMS/HYPOTHESIS

We investigated the prognostic value of clinic and ambulatory BP (ABP) to predict new-onset diabetes and whether risk reduction is related to the progressive decrease of clinic BP or awake or asleep ABP.

METHODS

We prospectively evaluated 2,656 individuals without diabetes, 1,292 men and 1,364 women, 50.6 ± 14.3 years of age, with baseline BP ranging from normotension to hypertension according to ABP criteria. At baseline and annually (more frequently if hypertension treatment was adjusted based on ABP) thereafter, ABP and physical activity (wrist actigraphy) were simultaneously monitored for 48 h to accurately derive the awake and asleep BP means.

RESULTS

During a 5.9-year median follow-up, 190 participants developed type 2 diabetes. The asleep systolic ABP mean was the most significant predictor of new-onset diabetes in a Cox proportional-hazard model adjusted for age, waist circumference, glucose, chronic kidney disease (CKD) and hypertension treatment. Daytime clinic BP and awake or 48 h ABP mean had no predictive value when corrected by the asleep ABP mean. Analyses of BP changes during follow-up revealed a 30% reduction in the risk of new-onset diabetes per 1-SD decrease in asleep systolic ABP mean, independent of changes in clinic BP or awake or 48 h ABP means.

CONCLUSIONS/INTERPRETATION

Sleep-time BP is a highly significant independent prognostic marker for new-onset diabetes. Alteration in sleep-time BP regulation seems to precede, rather than follow, the development of new-onset diabetes. Most important, lowering asleep BP, a novel therapeutic target requiring ABP evaluation, could be a significant method for reducing new-onset diabetes risk.

Blood pressure variability: assessment, predictive value, and potential as a therapeutic target

A large body of evidence has consistently supported the relationship between blood pressure (BP) levels and the risk of cardiovascular complications. In recent years, several independent studies have also indicated that this risk may not only depend on the magnitude of the blood pressure elevation per se but also on the presence of other associated conditions such as increased blood pressure variability. This concept has been supported by a series of reports, most of which post hoc analyses of clinical trials in hypertension, showing that increasing values of BP variability (BPV) (either in the short term, in the midterm, or in the long term) may predict development, progression, and severity of cardiac, vascular, and renal organ damage, as well as cardiovascular events and mortality. Remarkably, studies conducted in populations at high cardiovascular risk have shown increasing values of BPV in the individual subjects (so-called intra- or within-individual BPV) to be strong predictors of cardiovascular morbidity and mortality, even to a larger extent than average BP values. However, in subjects at low to moderate cardiovascular risk, the contribution of BPV to cardiovascular risk prediction over and beyond average BP values has been shown to be only moderate. The aim of this paper is to critically review the evidence addressing the prognostic relevance of different components of BPV addressing a yet open question, i.e., whether routine assessment of BPV in clinical practice should be regarded as an additional target of antihypertensive treatment to improve cardiovascular protection.