Validation of the Welch Allyn 'Vital Signs' oscillometric blood pressure monitor

Video plethysmography for contactless blood pressure and heart rate measurement in perioperative care

The purpose of this study was to evaluate the feasibility and accuracy of remote Video Plethysmography (VPPG) for contactless measurements of blood pressure (BP) and heart rate (HR) in adult surgical patients in a hospital setting. An iPad Pro was used to record a 1.5-minute facial video of the participant's face and VPPG was used to extract vital signs measurements. A standard medical device (Welch Allyn) was used for comparison to measure BP and HR. Trial registration: NCT05165381. Two-hundred-sixteen participants consented and completed the contactless BP and HR monitoring (mean age 54.1 ± 16.8 years, 58% male). The consent rate was 75% and VPPG was 99% successful in capturing BP and HR. VPPG predicted SBP, DBP, and HR with a measurement bias ± SD, -8.18 ± 16.44 mmHg, - 6.65 ± 9.59 mmHg, 0.09 ± 6.47 beats/min respectively. Pearson's correlation for all measurements between VPPG and standard medical device was significant. Correlation for SBP was moderate (0.48), DBP was weak (0.29), and HR was strong (0.85). Most patients were satisfied with the non-contact technology with an average rating of 8.7/10 and would recommend it for clinical use. VPPG was highly accurate in measuring HR, and is currently not accurate in measuring BP in surgical patients. The VPPG BP algorithm showed limitations in capturing individual variations in blood pressure, highlighting the need for further improvements to render it clinically effective across all ranges. Contactless vital signs monitoring was well-received and earned a high satisfaction score.

Comparison of the Omron HeartGuide to the Welch Allyn ProBP 3400 blood pressure monitor

Hypertension affects approximately 100 million U.S. adults and is the leading single contributing risk factor to all-cause mortality. Accurate blood pressure (BP) measurement is essential in the treatment of BP, and a number of devices exist for monitoring. Recently, a new watch-type design was released, the Omron HeartGuide (BP8000), with claims to provide clinically accurate BP measurement while also tracking activity and sleep similar to smart watches. The aim of this research was done in two studies: (1) evaluation of the HeartGuide device for measurement of resting BP and heart rate (HR); and (2) assessment of the HeartGuide for BP, HR, step-counting and sleep monitoring during activities of daily living. Study 1 compared the Omron HeartGuide to the previously validated Welch Allyn ProBP 3400 following a modified version of the Universal Standard for validation of BP measuring devices set by the AAMI/ESH/ISO. While resting HR measured by the HeartGuide was similar to Welch Allyn measures, both systolic and diastolic BP were significantly lower ( P ≤0.001), with differences of 10.4 (11.1) and 3.2 (10.0) mmHg, respectively. Study 2 compared HeartGuide measures to Welch Allyn measures for BP, HR, steps and sleep during various body positions (supine, seated, standing), physiological stressors (cold pressor test, lower body submersion, exercise), and free-living. The HeartGuide significantly underestimated BP though provided accurate HR during most conditions. It also significantly underestimated steps, but reported sleep measures similar to those subjectively reported. Based on the significant differences between the HeartGuide and Welch Allyn, our data indicate the HeartGuide is not a suitable replacement for existing BP monitors.

Neighborhood Socioeconomic Deprivation in Early Childhood Mediates Racial Disparities in Blood Pressure in a College Student Sample

The influence of childhood contexts on adult blood pressure is an important yet understudied topic. Using a developmental perspective, this study examines the association between neighborhood socioeconomic disadvantage in early childhood (0-5 yrs), middle childhood (6-12 yrs) and adolescence (13-18 yrs) on subsequent blood pressure in young adulthood. Data were from 263 college students (52% Black; M_age = 19.21 years) and neighborhood socioeconomic disadvantage was measured using a tract-level Area Deprivation Index. Neighborhood disadvantage in early childhood was significantly associated with diastolic blood pressure and explained 22% of the race difference between Black and White adults. The findings are consistent with the notion that early childhood may be a sensitive period for the effects of neighborhood disadvantage on blood pressure.

Hypertension-mediated organ damage in masked hypertension

OBJECTIVES

Masked hypertension - a blood pressure (BP) phenotype characterized by a clinic BP in the normal range but elevated BP outside the office - is associated with early hypertension-mediated organ damage. This study examined early target organ manifestations of masked hypertension diagnosed by home (HBPM) and ambulatory (ABPM) BP monitoring.

METHODS

Left ventricular (LV) structure and diastolic function measured by echocardiography, microalbuminuria, and coronary artery calcification were evaluated in 420 patients with high clinic BP (SBP 120-150 mmHg or DBP 80-95 mmHg). Evidence of hypertension-mediated organ damage was compared in patients with sustained normotension, masked hypertension, and sustained hypertension based on measurements by HBPM, daytime ABPM, and 24-h ABPM.

RESULTS

The 420 participants averaged 48 (12) [mean (SD)] years of age; the average clinic BP was 130 (13)/81 (8) mmHg. In individuals with masked hypertension diagnosed by HBPM, indexed LV mass, relative wall thickness, and e' and E/e' (indices of LV relaxation), were generally intermediate between values observed in normotensives and sustained hypertensive patients, and were significantly greater in masked hypertension than normotensives. Similar trends were observed when masked hypertension was diagnosed by ABPM but a diagnosis of masked hypertension was not as reliably associated with LV remodeling or impaired LV relaxation in comparison to normotensives. There were trends towards greater likelihoods of detectable urinary microalbumin and coronary calcification in masked hypertension than in normotensives.

CONCLUSION

These results support previous studies demonstrating early hypertension-mediated organ damage in patients with masked hypertension, and suggest that HBPM may be superior to ABPM in identifying patients with masked hypertension who have early LV remodeling and diastolic LV dysfunction.

Impact of Systolic Blood Pressure on Heart Failure Symptoms With Moderate Aortic Stenosis

In patients with moderate aortic stenosis (AS), heart failure (HF) symptoms are often unrelated to the AS severity, and the causes of HF symptoms are often unclear. Hypertension is known as one of the most common comorbidities in degenerative AS. Therefore, we assessed the impact of systolic blood pressure (BP) on HF symptoms in patients with moderate AS. We retrospectively analyzed 317 patients with moderate AS (mean transaortic pressure gradient 20 to 39 mm Hg) and preserved left ventricular ejection fraction (left ventricular ejection fraction ≥50%). We classified patients according to the presence or absence of HF symptoms. One hundred patients (32%) had HF symptoms. Symptomatic patients had higher systolic BP (141±21 versus 129±21 mm Hg; p<0.001) and mean transaortic pressure gradient, and lower aortic valve area than asymptomatic patients. In the multivariable analysis after adjustment for age, atrial fibrillation, Charlson comorbidity index, brain natriuretic peptide, and the use of diuretics, HF symptoms in patients with moderate AS were independently associated with systolic BP (odds ratio, 1.43 per 10 mm Hg increase in systolic BP; 95% confidence interval, 1.14-1.78; p=0.001) and left atrial volume index (odds ratio, 1.04 per 1 mL/m² increase in left atrial volume index; 95% confidence interval, 1.00-1.08; p=0.026). Receiver operating characteristics curve analysis identified systolic BP 133 mm Hg as the cutoff value associated with HF symptoms. In conclusion, systolic BP as well as left atrial volume index were independent correlates of HF symptoms in patients with moderate AS.

Comparing Intra-Arterial, Auscultatory, and Oscillometric Measurement Methods for Arterial Blood Pressure

AIM

This study aimed to compare the measurement results of arterial blood pressure obtained through intra-arterial, auscultatory, and oscillometric methods.

METHOD

This prospective and descriptive study was conducted with 180 patients hospitalized in the intensive care units of cardiovascular surgery and anesthesia. Arterial blood pressures of the patients in the study were measured with 3 methods, and the mean arterial pressure values obtained by each method were analyzed to find out whether they were different or consistent.

RESULTS

The average systolic blood pressure value using the intra-arterial method was found to be 125.47 ± 21.39 mm Hg, and the average of diastolic blood pressure measurement obtained using the oscillometric method was the highest (73.91 ± 10.62 mm Hg). The highest correlation was seen between the arterial BP measurements of the intra-arterial and auscultatory methods (systolic [0.96] and diastolic [0.90]). According to the British and Irish Hypertension Society protocol, a very good agreement between the diastolic blood pressure values and a good agreement between the systolic blood pressure values were obtained.

CONCLUSION

The measurement results obtained through the auscultatory method more consistent with the results obtained through the intra-arterial method compared with those obtained using the oscillometric method.

Low admission blood pressure as a marker of poor 1-year survival in patients with revascularized critical limb ischemia

OBJECTIVE

To contrast the association between blood pressure (BP) level and antihypertensive medications at hospital admission with 1-year mortality in patients undergoing revascularization for critical limb ischemia (CLI).

METHODS

From November 2013 to May 2019, 315 consecutive patients were retrospectively included. A median of seven (IQR 3-13) separate readings were recorded for each patient before revascularization procedure and the average represented patient's mean BP. BP-lowering medications, clinical and biological parameters were recorded at baseline. The main outcome was total 1-year mortality.

RESULTS

The cohort included 172 men (55%) and 143 women (45%), with a mean age of 77.9 ± 11.9 years. Treated hypertension was present in 245 (78%) patients; 288 (91%) patients had BP-lowering drug prescriptions (2.1 ± 1.3 medications at baseline). Mean SBP, DBP, mean BP (MBP) and pulse pressure (PP) were 132 ± 18, 70 ± 8, 90 ± 10 and 62 ± 16mmHg. During 1-year follow-up, 80 (25.4%) patients died. In single-pressure multivariate analysis, SBP (hazard ratio 0.97; 95% CI 0.96-0.99; P = 0.005), MBP (hazard ratio 0.96; 95% CI 0.92-0.99; P = 0.01), PP (hazard ratio 0.97; 95% CI 0.95-0.99; P = 0.009), but not DBP, were inversely correlated with 1-year mortality, independently of age, coronary heart disease, left ventricular ejection fraction, brain natriuretic peptide, serum albumin, institutionalized status and antihypertensive drugs. Association between SBP, MBP and PP with 1-year mortality had a quite linear reverse pattern.

CONCLUSION

Among patients undergoing revascularization for CLI, there is an inverse correlation between admission SBP, MBP and PP with 1-year mortality. BP may represent a modifiable therapeutic target to prevent poor outcome in CLI patients.

Relationship between adherence to diet and physical activity guidelines and self-efficacy among black women with high blood pressure

Hypertension prevalence is highest among Black women in America. Understanding the relationship between adherence to diet and physical activity using socio-cognitive approaches (e.g. self-efficacy and social support) may be effective approaches in understanding hypertension management. This study found that dietary self-efficacy was associated with dietary adherence, and family social support was associated with both diet and physical activity self-efficacy. Social support mediated the relationship between dietary self-efficacy and dietary adherence. A paradoxical finding emerged where participants in the highest self-efficacy tertile also had higher measured systolic blood pressure. More research is necessary to explore culture-specific factors underlying hypertension treatment management among Black women.

Uptake and effectiveness of a tailor-made online lifestyle programme targeting modifiable risk factors for dementia among middle-aged descendants of people with recently diagnosed dementia: study protocol of a cluster randomised controlled trial (Demin study)

INTRODUCTION

Descendants of patients with dementia have a higher risk to develop dementia. This study aims to investigate the uptake and effectiveness of an online tailor-made lifestyle programme for dementia risk reduction (DRR) among middle-aged descendants of people with recently diagnosed late-onset dementia.

METHODS AND ANALYSIS

Demin is a cluster randomised controlled trial, aiming to include 21 memory clinics of which 13 will be randomly allocated to the passive (poster and flyer in a waiting room) and 8 to the active recruitment strategy (additional personal invitation by members of the team of the memory clinic). We aim to recruit 378 participants (40-60 years) with a parent who is recently diagnosed with Alzheimer's disease or vascular dementia at one of the participating memory clinics. All participants receive a dementia risk assessment (online questionnaire, physical examination and blood sample) and subsequently an online tailor-made lifestyle advice regarding protective (Mediterranean diet, low/moderate alcohol consumption and high cognitive activity) and risk factors (physical inactivity, smoking, loneliness, cardiovascular diseases (CVD), hypertension, high cholesterol, diabetes, obesity, renal dysfunction and depression) for dementia. The primary outcome is the difference in uptake between the two recruitment strategies. Secondary outcomes are change(s) in (1) the Lifestyle for Brain Health score, (2) individual health behaviours, (3) health beliefs and attitudes towards DRR and (4) compliance to the tailor-made lifestyle advice. Outcomes will be measured at 3, 6, 9 and 12 months after baseline. The effectiveness of this online tailor-made lifestyle programme will be evaluated by comparing Demin participants to a matched control group (lifelines cohort).

ETHICS AND DISSEMINATION

This study has been approved by the Dutch Ministry of Health, Welfare and Sport according to the Population Screening Act. All participants have to give online informed consent using SMS-tan (transaction authentication number delivered via text message). Findings will be disseminated through peer-reviewed journals and (inter)national conferences.

TRIAL REGISTRATION NUMBER

NTR7434.

The Get-Up! study: adiposity and blood pressure in Australian toddlers

BACKGROUND

Because the elevated blood pressure (BP) in childhood is strongly associated with overweight and is a risk factor for later cardiovascular disease, a need to comprehend the early development of BP and its association with overweight is needed. We assessed differences of BP by weight status in Australian toddlers.

METHODS

From the Get-Up! Study in Australia, this sample included 265 toddlers (136 boys), aged 19.6 ± 4.2 months. BP was measured with a digital vital signs monitor. Participants were categorized as nonoverweight and overweight according to the World Health Organization definition for body mass index (BMI). Physical activity was captured with activPAL accelerometers, during childcare hours. To test differences in BP between nonoverweight and overweight children, we performed an analysis of covariance adjusting for sex, age, physical activity, and socioeconomic status.

RESULTS

Children with overweight showed higher z systolic BP values (P = .042 for BMI and P = .023 for waist circumference) when compared to nonoverweight children. However, no differences were found for z diastolic BP levels, between overweight and nonoverweight children. After adjustments for potential confounders (socioeconomic status, physical activity, sex, and age), there were no significant differences in BP variables between BMI and waist circumference groups.

CONCLUSIONS

No associations between adiposity and BP levels were found in this sample. The unadjusted results, however, showed that children with higher levels of adiposity (BMI and waist circumference) exhibited higher levels of BP. Additional research is needed to determine which environmental and genetic factors might contribute to pediatric hypertension, particularly among toddlers.

The prevalence of masked hypertension in a group of young healthy soldiers

BACKGROUND

To assess the prevalence of masked hypertension (MH) in young Saudi National Guard soldiers based on 24h ambulatory blood pressure monitoring (ABPM).

METHODS

A prospective study of 196 soldiers, aged between 21-50 years, without a history of hypertension or antihypertensive medication use. Each participant was fitted with a 24h-ABPM. Patients were considered to have MH if the office blood pressure (OBP) was <140/90 mm Hg and the 24h-ABPM average was ≥130/80 mmHg.

RESULTS

The mean age of the MH group was 34.5 years compared to 32.4 years of the normotensive group. By pairing the average OBP with the 24h-ABPM, the prevalence of MH was estimated to be 29/196 (14.8%), with the SBP (systolic blood pressure) and DPB MH (diastolic BP) prevalence 12.8% and 7.7%, respectively. For the systolic BP, the OBP compared with the 24h-ABPM was 120.0±8.1 vs. 134.7±4.5 (P<0.001) and for the diastolic BP, 70.7±7.0 vs. 79.9±4.2 (P<0.001).

CONCLUSIONS

The prevalence of MH among this sample of healthy military soldiers was 14.8%. It is important not to rely solely on the OBP and to consider MH when screening for hypertension in apparently healthy individuals.

Associations of weight cycling with cardiovascular health using American Heart Association's Life's Simple 7 in a diverse sample of women

Prior research shows that weight cycling is associated with poorer cardiovascular health (CVH). Women experience unique life events (e.g. pregnancy, menopause) which may make them more prone to weight cycling. Examining the influence of weight cycling history (HWC) on CVH, quantified using the American Heart Association's Life's Simple 7 (LS7), may provide novel targets to improve CVH. A cross-sectional sample of 485 women at Columbia University Irving Medical Center (2016-2018) were scored on each LS7 metric (BMI, blood pressure, fasting cholesterol and glucose, physical activity, diet, and smoking): 0 (low), 1 (moderate) or 2 (high). Metric points were summed into a composite LS7 score as a measure of CVH: 0-8 (low), 9-10 (moderate), 11-14 (high). Multivariable-adjusted logistic and linear regression models were used for the associations between HWC and CVH. Most women (73%) reported HWC (range: 0-20); 26% had low CVH and 74% moderate/high CVH. Logistic models showed HWC was associated with higher odds of having poor CVH [OR (95%CI): 2.39 (1.36-4.20)]. Linear models showed each additional weight cycling episode was associated with lower LS7 scores [ß(SE): -0.37 (0.07); p < 0.01]. Associations between HWC and odds of having poor CVH were stronger among pre-menopausal women and those with no pregnancy history (p-interaction = 0.009, 0.004, respectively). In conclusion, HWC was associated with higher odds of poorer CVH with stronger associations seen in pre-menopausal and women with no pregnancy history. These findings suggest that in addition to having a healthy weight, maintaining a consistent weight may be important for achieving optimal CVH, but warrant prospective confirmation.

Superiority of Out-of-Office Blood Pressure for Predicting Hypertensive Heart Disease in Non-Hispanic Black Adults

Black Americans suffer disproportionately from hypertension and hypertensive heart disease. Out-of-office blood pressure (BP) is more predictive for cardiovascular complications than clinic BP; however, the relative abilities of clinic and out-of-office BP to predict left ventricular hypertrophy in black and white adults have not been established. Thus, we aimed to compare associations of out-of-office and clinic BP measurement with left ventricular hypertrophy by cardiac magnetic resonance imaging among non-Hispanic black and white adults. In this cross-sectional study, 1262 black and 927 white participants of the Dallas Heart Study ages 30 to 64 years underwent assessment of standardized clinic and out-of-office (research staff-obtained) BP and left ventricular mass index. In multivariable-adjusted analyses of treated and untreated participants, out-of-office BP was a stronger determinant of left ventricular hypertrophy than clinic BP (odds ratio per 10 mm Hg, 1.48; 95% CI, 1.34-1.64 for out-of-office systolic BP and 1.15 [1.04-1.28] for clinic systolic BP; 1.71 [1.43-2.05] for out-of-office diastolic BP, and 1.03 [0.86-1.24] for clinic diastolic BP). Non-Hispanic black race/ethnicity, treatment status, and lower left ventricular ejection fraction were also independent determinants of hypertrophy. Among treated Blacks, the differential association between out-of-office and clinic BP with hypertrophy was more pronounced than in treated white or untreated participants. In conclusion, protocol-driven supervised out-of-office BP monitoring provides important information that cannot be gleaned from clinic BP assessment alone. Our results underscore the importance of hypertension management programs outside the medical office to prevent hypertensive heart disease, especially in high-risk black adults. Clinical Trial Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT00344903.

Diagnostic Thresholds for Blood Pressure Measured at Home in the Context of the 2017 Hypertension Guideline

Most guidelines have recommended lower home blood pressure (BP) threshold when clinic BP threshold of 140/90 mm Hg is used for diagnosis of hypertension. However, home BP thresholds to define hypertension have never been determined in the general population in the United States. We identified home BP thresholds for stage 1 (BP ≥130/80 mm Hg) hypertension using a regression-based approach in the DHS (Dallas Heart Study; n=5768) and the NCMH study (North Carolina Masked Hypertension; n=420). Home BP thresholds were also assessed using outcome-derived approach based on the composite of all-cause mortality or cardiovascular events in the DHS cohort. For this approach, BP thresholds were identified only for systolic BP because diastolic BP was not associated with the outcome. Among untreated participants, the regression-derived thresholds for home BP corresponding to clinic BP for stage 1 hypertension were 129/80 mm Hg in blacks, 130/80 mm Hg in whites, and 126/78 mm Hg in Hispanics, respectively. The results are similar in the North Carolina cohort. The 11-year composite cardiovascular and mortality events corresponding to clinic systolic BP >130 mm Hg were higher in blacks than in whites and Hispanics (13.3% versus 5.98% versus 5.52%, respectively). Using a race/ethnicity-specific composite outcome in the untreated DHS participants, the outcome-derived home systolic BP thresholds corresponding to stage 1 hypertension were 130 mm Hg in blacks, 129 mm Hg in whites, and 131 mm Hg in Hispanics, respectively. Our data based on both regression-derived and outcome approach support home BP threshold of 130/80 mm Hg for diagnosis of hypertension in blacks, whites, and Hispanics.

Measurement of Blood Pressure in Humans: A Scientific Statement From the American Heart Association

The accurate measurement of blood pressure (BP) is essential for the diagnosis and management of hypertension. This article provides an updated American Heart Association scientific statement on BP measurement in humans. In the office setting, many oscillometric devices have been validated that allow accurate BP measurement while reducing human errors associated with the auscultatory approach. Fully automated oscillometric devices capable of taking multiple readings even without an observer being present may provide a more accurate measurement of BP than auscultation. Studies have shown substantial differences in BP when measured outside versus in the office setting. Ambulatory BP monitoring is considered the reference standard for out-of-office BP assessment, with home BP monitoring being an alternative when ambulatory BP monitoring is not available or tolerated. Compared with their counterparts with sustained normotension (ie, nonhypertensive BP levels in and outside the office setting), it is unclear whether adults with white-coat hypertension (ie, hypertensive BP levels in the office but not outside the office) have increased cardiovascular disease risk, whereas those with masked hypertension (ie, hypertensive BP levels outside the office but not in the office) are at substantially increased risk. In addition, high nighttime BP on ambulatory BP monitoring is associated with increased cardiovascular disease risk. Both oscillometric and auscultatory methods are considered acceptable for measuring BP in children and adolescents. Regardless of the method used to measure BP, initial and ongoing training of technicians and healthcare providers and the use of validated and calibrated devices are critical for obtaining accurate BP measurements.

Blood Pressure Measurement in Severely Obese Patients: Validation of the Forearm Approach in Different Arm Positions

BACKGROUND

Blood pressure measurement in severe obesity may be technically challenging as the cuff of the device may not fit adequately around the upper arm. The aim of the study was to assess the agreement between intra-arterial blood pressure values (gold standard) compared with forearm blood pressure measurements in severely obese patients in different arm positions.

METHODS

Thirty-three severely obese patients and 21 controls participated in the study. Pairs of intra-arterial blood pressures were compared with simultaneous forearm blood pressure measurement using an oscillometric device in 4 positions: (i) supine, (ii) semi-fowler with the forearm resting at heart level, (iii) semi-fowler with the arm downward, and (iv) semi-fowler with the arm raised overhead. Degree of agreement between measurements was assessed.

RESULTS

Overall, correlations of systolic and diastolic blood pressure measurements between the gold standard and forearm blood pressure were 0.95 (n = 722; P < 0.001) and 0.89 (n = 482; P < 0.001), respectively. Systolic blood pressure measured using the forearm approach in the supine and the semi-fowler positions with arm downward showed the best agreement when compared with the gold standard (-4 ± 11 (P < 0.001) and 2 ± 14 mm Hg (P = 0.19), respectively). In the control group, better agreement was found between the supine and semi-fowler positions with the arm resting at heart level (1 ± 9 mm Hg (P = 0.29) and -3 ± 10 mm Hg (P = 0.01), respectively).

CONCLUSIONS

Forearm systolic blood pressure consistently agreed with the gold standard in the supine position. This method can be of use in clinical settings when upper-arm measurement is challenging in severe obesity.

Stress, adherence, and blood pressure control: A baseline examination of Black women with hypertension participating in the SisterTalk II intervention

The prevalence of hypertension is highest among Black women, but treatment adherence is reportedly low. Stress unique to the experiences of Black Americans may be associated with low adherence and poor blood pressure control, but few studies have examined the relationships between stress, adherence, and blood pressure control among hypertensive Black women. This study seeks to fill gaps in research by examining the association between stress, adherence, and blood pressure control. The baseline sample (n = 571) of at-risk or hypertensive Black women from the SisterTalk II RCT (Northeastern USA, 2004-2006) to improve adherence to recommendations for hypertension was analyzed. Participants self-reported stress, pharmacological adherence, non-pharmacological adherence (i.e. lifestyle management such as diet and exercise), and demographics. Blood pressure and anthropometrics (BMI and waist circumference) were measured. Statistical analysis included ANOVA, t-tests, linear regression. Tests of mediation examined if adherence mediated the relationship between stress and blood pressure control. This study found that stress was associated with lower age (p < .001) and being a single parent (p < .001). Stress was also associated with higher systolic blood pressure (p = .029), and poor blood pressure control (p = .043). Participants who reported higher stress also reported lower non-pharmacological adherence (p = .042). Non-pharmacological adherence was found to mediate the association between stress and blood pressure control. Hence, results document a relationship between stress with non-pharmacological adherence and blood pressure control among Black American women. More research is necessary to examine the relationship between stress and treatment adherence.

The Reproducibility of Racial Differences in Ambulatory Blood Pressure Phenotypes and Measurements

BACKGROUND

We examined the reproducibility of differences in ambulatory blood pressure (BP) monitoring (ABPM) phenotypes and other parameters (sustained hypertension, masked hypertension, nocturnal hypertension, and nondipping) between African Americans and Whites.

METHODS

A total of 420 participants untreated for hypertension attended 2 research visits 1 week apart during which traditional office BP averages and ABPM session averages were determined. We computed percent agreement in ABPM phenotypes across the 2 visits stratified by race and associated kappa statistics with 95% confidence intervals.

RESULTS

Whites on average were older, more likely to be male, and had a higher body mass index. There was no significant difference in sleep quality as defined by sleep diary between the 2 races. There were also no significant differences between races in the proportions of participants with sustained hypertension, sustained normotension, or masked hypertension at either testing session. The prevalence of nocturnal hypertension was 59% vs. 75% (P = 0.012) at session 1 and 59% vs. 73% (P = 0.024) at session 2 for Whites and African Americans, respectively, with moderate reproducibility for both (kappas 0.45 and 0.44). Nocturnal BP nondipping had a prevalence 29% vs. 53% (P < 0.001) at session 1 and 29% vs. 47% (P = 0.004) at session 2 for Whites and African Americans, respectively, with fair reproducibility (kappas 0.28 and 0.29).

CONCLUSIONS

Our findings support that African Americans indeed exhibit a greater preponderance of abnormal nocturnal BP patterns than Whites. Our work is some of the first to demonstrate that these abnormal patterns are modestly reproducible.

An inaccurate automated device negatively impacts the diagnosis and treatment of gestational hypertension

OBJECTIVES

Automated blood pressure devices are frequently introduced in maternity care without prior validation for their accuracy in pregnancy. Our objectives were to, firstly, establish the accuracy in pregnancy of a locally used device (Welch Allyn 300) and, secondly, to audit its impact on the diagnosis and treatment of hypertension.

STUDY DESIGN

Validation study: The device was evaluated using the grading criteria of the European Society of Hypertension International Protocol (ESH-IP) (2010). Two observers took nine same-arm measurements alternating between the Welch Allyn and the mercury sphygmomanometer. Thirty-three women of any gestation were included. Clinical audit: One observer took three same-arm measurements alternating between the Welch Allyn and the mercury sphygmomanometer. One hundred women of any gestation referred with suspected hypertension were included. The main outcome measures were the proportion diagnosed with hypertension or commenced on anti-hypertensive treatment on the presenting visit when using either the manual or the automated device.

MAIN OUTCOME MEASURES

Grading criteria of the ESH-IP (2010) and proportion of women diagnosed with hypertension or commenced on antihypertensive therapy at the presenting visit when using either manual sphygmomanometry or the Welch Allyn device.

RESULTS

The Welch Allyn 300 series failed to meet the criteria of the ESH-IP (2010) for pregnancy. Compared to the mercury device, it under diagnosed hypertension by 48% and need for treatment by 80%.

CONCLUSIONS

The Welch Allyn 300 cannot be recommended for the measurement of blood pressure in pregnancy. Its use leads to the under-diagnosis and under-treatment of gestational hypertension.

Neighborhood perceptions and hypertension among low-income black women: a qualitative study

Background

The majority of studies examining the role of neighborhoods and hypertension-related outcomes have been quantitative in nature and very few studies have examined specific disadvantaged populations, including low-income housing residents. The objective of this study was to use qualitative interviews to explore low-income Black women’s perceptions of their neighborhoods and to understand how those perceptions may affect their health, especially as it relates to blood pressure.

Methods

Seventeen Black female participants, living in public housing communities in New York City, completed one semi-structured, audiotaped interview in July of 2014. All interviews were transcribed, coded, and analyzed for emerging themes using N’Vivo 10 software.

Results

Three major themes emerged: (1) social connectedness, (2) stress factors, and (3) availability of food options. For example, factors that caused stress varied throughout the study population. Sources of stress included family members, employment, and uncleanliness within the neighborhood. Many participants attributed their stress to personal issues, such as lack of employment and relationships. In addition, the general consensus among many participants was that there should be a greater density of healthy food options in their neighborhoods. Some believed that the pricing of fresh foods in the neighborhoods should better reflect the financial status of the residents in the community.

Conclusions

Various neighborhood influences, including neighborhood disorder and lack of healthy food options, are factors that appear to increase Black women’s risk of developing high blood pressure. Implications of this research include the need to develop interventions that promote good neighborhood infrastructure (e.g. healthy food stores to encourage good nutrition habits and well-lit walking paths to encourage daily exercise), in addition to interventions that increase hypertension awareness in low-income neighborhoods.

Examination of Several Physiological and Psychosocial Factors Potentially Associated With Masked Hypertension Among Low-Risk Adults

The authors examined the association of factors, in addition to prehypertensive office blood pressure (BP) level, that might improve detection of masked hypertension (MH), defined as nonelevated office BP with elevated out-of-office BP average, among individuals at otherwise low risk. This sample of 340 untreated adults 30 years and older with average office BP <140/90 mm Hg all had two sets of paired office BP measurements and 24-hour ambulatory BP monitoring (ABPM) sessions 1 week apart. Other than BP levels, the only factors that were associated (at P<.10) with MH at both sets were male sex (75% vs 66%) and working outside the home (72% vs 59% for the first set and 71% vs 45% for the second set). Adding these variables to BP level in the model did not appreciably improve detection of MH. No demographic, clinical, or psychosocial measures that improved upon prehypertension as a potential predictor of MH in this sample were found.

Carotid extramedial thickness is associated with local arterial stiffness in children

OBJECTIVES

Experimental evidence suggests that structural changes to the arterial adventitia may be a key vascular determinant of early arterial stiffening, although this has not been directly studied. Accordingly, we hypothesized that in young children, in whom this relationship would not be altered by atheroma, carotid extramedial thickness (EMT), a measure that incorporates the thickness of the arterial adventitia, perivascular tissues and the internal jugular venous wall, would be associated with localized arterial stiffness of the same arterial region.

METHODS

We studied 248 healthy prepubescent children (aged 8 years). Carotid diameter and carotid EMT were measured by high-resolution ultrasound. Carotid blood pressure was derived from brachial blood pressure and carotid tonometry. Three measures of localized arterial stiffness (β stiffness index, distensibility coefficient and incremental modulus of elasticity) were calculated for the common carotid artery. Results were adjusted for heart rate and DBP, two important hemodynamic determinants of arterial stiffness.

RESULTS

Carotid EMT was associated with all three measures of arterial stiffness (β stiffness index: standardized β = 0.121, P = 0.03; distensibility coefficient: standardized β = -0.121, P = 0.05; incremental modulus of elasticity: standardized β = 0.140, P = 0.02). These associations remained significant after adjustment for potential confounders such as sex, height, waist circumference, BMI and body surface area.

CONCLUSION

Carotid EMT is associated with the stiffness of the same arterial segment in children, suggesting that the arterial adventitia may be involved in early changes in arterial stiffness during childhood.

Target organ complications and prognostic significance of alerting reaction: analysis from the Dallas Heart Study

OBJECTIVE

Noninvasive blood pressure (BP) measurement often triggers a transient rise in BP, known as an alerting reaction. However, the prevalence and prognostic significance of the alerting reaction has never been assessed in the general population.

METHODS

We evaluated the association between the alerting reaction and left ventricular mass by MRI and urinary albumin-to-creatinine ratio in the Dallas Heart Study, a large population sample of 3069 individuals. Participants were categorized into four groups based on levels of consecutive BP: first, normal first BP and average third to fifth (avg3-5) BP of less than 140/90 mmHg (control group); second, high first BP of at least 140/90 mmHg and normal (avg3-5) BP (alerting reaction group); third, normal first BP and high (avg3-5) BP; and fourth, high first to fifth BP. Then, associations between BP categories with incident cardiovascular outcomes (coronary heart disease, stroke, atrial fibrillation, heart failure, and cardiovascular death) over a median follow-up period of 9.4 years were assessed.

RESULTS

The sample-weighted prevalence of isolated hypertension during the first BP measurement was 9.6%. Presence of an alerting reaction was independently associated with increased left ventricular mass, urinary albumin-to-creatinine ratio, cardiovascular events after adjustment for traditional cardiovascular risk factors, and baseline BP (adjusted hazard ratio 1.24, 95% confidence interval 1.07-1.43).

CONCLUSION

Our study indicated that the alerting reaction is independently associated with increased cardiovascular and renal complications.

Oscillometric casual blood pressure normative standards for Swedish children using ABPM to exclude casual hypertension

BACKGROUND

Casual blood pressure (CBP) is considered a reliable proxy for cardiovascular health. Although the auscultatory technique is the reference standard method for measuring CBP, oscillometric devices are increasingly being used in children. We sought to establish oscillometric CBP normative standards for Swedish children.

METHODS

Cross-sectional oscillometric CBP readings were obtained by the Welch Allyn Spot Vital Signs 420 monitor and measured according to the International Guidelines' recommendations. Participants with elevated oscillometric CBP levels underwent verification by the auscultatory method. Ambulatory blood pressure monitoring (ABPM) was used to exclude casual hypertension. Data on 1,470 (772 males) apparently healthy Swedish schoolchildren aged 6-16 years were analyzed and sex-specific reference charts normalized to age or height were constructed.

RESULTS

Systolic and diastolic CBP values were significantly higher with age, height, height standard deviation score (SDS), body mass index (BMI), and BMI SDS. Gender differences for systolic CBP were present starting from age of 15 years and revealed significantly higher values in boys than in girls, whereas for diastolic CBP, the differences were apparent at the age of 12 years, with higher values in girls. Increased BMI and BMI SDS were positively associated with CBP levels. Positive parental history of hypertension turned out to be a risk factor for higher systolic and diastolic CBP across all ages.

CONCLUSIONS

Our normative standard for CBP can be used for blood pressure screening and control programs in Swedish children. The use of ABPM should be considered to confirm the diagnosis of casual hypertension.

Reproducibility of masked hypertension among adults 30 years or older

OBJECTIVE

Masked hypertension (MH) refers to nonelevated office blood pressure (BP) with elevated out-of-office BP, but its reproducibility has not been conclusively established. We examined 1-week reproducibility of MH by home BP monitoring (HBPM) and ambulatory BP monitoring (ABPM).

METHODS

We recruited 420 adults not on BP-lowering medication, with recent clinic BP between 120/80 and 149/95 mmHg. For main comparisons, participants with office average less than 140/90 mmHg were considered to have MH if awake ABPM average was 135/85 mmHg or higher; they were considered to have MH by HBPM if the average was 135/85 mmHg or higher. Percentage agreements were quantified in terms of κ. We also examined the prevalence of MH, defined as office average less than 140/90 mmHg, with a 24-h ABPM average of 130/80 mmHg or higher. We carried out sensitivity analyses using different threshold BP levels for ABPM-office pairings and HBPM-office pairings for defining MH.

RESULTS

Prevalence rates of MH based on office-awake ABPM pairings were 44 and 43%, with an agreement of 71% (κ=0.40; 95% confidence interval 0.31-0.49). MH was less prevalent (15 and 17%) using HBPM-office pairings, with agreement of 82% (κ=0.30; 95% confidence interval 0.16-0.44), and more prevalent when considering the 24-h average (50 and 48%). MH was also less prevalent when more stringent diagnostic criteria were applied. Office-HBPM pairings and office-awake ABPM pairings had fair agreement on MH classification on both occasions, with κ-values of 0.36 and 0.30.

CONCLUSION

MH has fair short-term reproducibility, providing further evidence that for some people, out-of-office BP is systematically higher than that measured in the office setting.

Levels of office blood pressure and their operating characteristics for detecting masked hypertension based on ambulatory blood pressure monitoring

BACKGROUND

Masked hypertension (MH)--nonelevated office blood pressure (BP) with elevated out-of-office BP average--conveys cardiovascular risk similar to or approaching sustained hypertension, making its detection of potential clinical importance. However, it may not be feasible or cost-effective to perform ambulatory BP monitoring (ABPM) on all patients with a nonelevated office BP. There likely exists a level of office BP below which ABPM is not warranted because the probability of MH is low.

METHODS

We analyzed data from 294 adults aged ≥ 30 years not on BP-lowering medication with office BP <140/90 mm Hg, all of whom underwent 24-hour ABPM. We calculated sensitivity, false-positive rate, and likelihood ratios (LRs) for the range of office BP cutoffs from 110 to 138 mm Hg systolic and from 68 to 88 mm Hg diastolic for detecting MH.

RESULTS

The systolic BP cutoff with the highest +LR for detecting MH (1.8) was 120 mm Hg, and the diastolic cutoff with the highest +LR (2.4) was 82 mm Hg. However, the systolic level of 120 mm Hg had a false-positive rate of 42%, and the diastolic level of 82 mm Hg had a sensitivity of only 39%.

CONCLUSIONS

The cutoff of office BP with the best overall operating characteristics for diagnosing MH is approximately 120/82 mm Hg. However, this cutoff may have an unacceptably high false-positive rate. Clinical risk tools to identify patients with nonelevated office BP for whom ABPM should be considered will likely need to include factors in addition to office BP.

Arterial pressure: agreement between a brachial cuff-based device and radial tonometry

Objectives:

Aortic (central) blood pressure (BP) differs from brachial BP and may be a superior predictor of cardiovascular events. However, its measurement is currently restricted to research settings, owing to a moderate level of operator dependency. We tested a new noninvasive device in a large UK cohort. The device estimates central BP using measurements obtained with an upper arm cuff inflated to suprasystolic pressure. We compared these estimates with those obtained using radial tonometry as well as with invasively acquired measurements of aortic BP in a limited number of individuals.

Methods:

Consecutive cuff-based and tonometry-based estimates of the pressure waveform and the central BP were obtained from 1107 individuals (70 ± 6 years). Short-term and long-term reproducibility studies were performed on 28 individuals. Simultaneous cuff-based and invasively measured pressure traces were acquired and compared in an additional six individuals (65 ± 20 years).

Results:

Central systolic BP, as estimated by the cuff-based device, was found to be highly reproducible (coefficient of variation 4 and 8% for short and long-term reproducibility, respectively) and was comparable to that estimated by tonometry (average difference 3 ± 6 mmHg, intraclass correlation coefficient = 0.91). The cuff-based pressure waveforms were similar to those acquired invasively (cross-correlation coefficient 0.93), and the difference in the estimated central systolic BP was −5 ± 8 mmHg (P = 0.2).

Conclusion:

Cuff-based devices show promise to simplify the measurement of central BP, whilst maintaining a similar fidelity to tonometry. This could lead to improved adoption of estimates of central BP in clinical practice.

Blood pressure assessment in severe obesity: validation of a forearm approach

OBJECTIVE

Obesity is frequently associated with systemic hypertension. Blood pressure measure is inaccurate in severely obese patients because of poor cuff size fitting. The aim of the study is to assess the degree of agreement between the intra-arterial method as the gold standard vs. noninvasive methods, i.e., forearm blood pressure and upper-arm blood pressure measures.

DESIGN AND METHODS

A total of 1285 measures of intra-arterial and forearm blood pressure were taken in 51 severely obese patients in a supine position in the operating and the recovery room. A subset of 352 upper-arm measures were taken in the recovery room and compared to the intra-arterial and the forearm methods.

RESULTS

Correlation between the intra-arterial and the forearm measures was 0.90 (P < 0.001) for the 2570 data (systolic and diastolic). Compared to intra-arterial, the forearm method overestimated systolic (6 ± 16 mm Hg, P < 0.001) and underestimated diastolic blood pressure (2 ± 11 mm Hg, P = 0.03). Compared to intra-arterial, upper-arm underestimated systolic (8 ± 16 mm Hg, P < 0.01) and overestimated diastolic blood pressure (9 ± 7 mm Hg, P < 0.001).

CONCLUSION

The magnitude of differences between the intra-arterial and forearm method was less than differences between the intra-arterial and upper-arm method. Our results suggest that forearm method may be a more accurate alternative to upper-arm measurement to assess blood pressure in severely obese patients.

Differential treatment of hypertension by primary care providers and hypertension specialists in a barber-based intervention trial to control hypertension in Black men

Black men have less physician contact than other groups and thus lower rates of hypertension treatment and control. In the Barber-Assisted Reduction in Blood Pressure among Ethnic Residents trial, hypertension control in 8 active-intervention barbershops where barbers offered blood pressure (BP) checks with haircuts and motivated black male patrons with high BP to seek provider follow-up showed a small improvement over that in 7 comparison shops where patrons received hypertension pamphlets but not barber-BP checks. Undertreatment of hypertension, which is common in primary care, may have impacted the outcomes. Thus, in patrons with a baseline systolic BP of ≥140 mm Hg and 10-month follow-up including BP and medication data, we performed post hoc comparison of systolic BP reduction between comparison-arm patrons (n = 68) treated by primary care providers (PCPs) with (1) intervention-arm patrons (n = 37) treated by PCPs or (2) intervention-arm patrons (n = 33) who lacked access to PCPs and were treated by hypertension specialist physicians serving as safety net providers. The latter group had higher baseline systolic BP than the others (162 ± 3 vs 155 ± 2 and 154 ± 2 mm Hg, respectively, p <0.01). After adjustment for baseline systolic BP and other covariates, systolic BP reduction was 21 ± 4 mm Hg greater than in the comparison group (p <0.0001), when barbers referred patrons to hypertension specialists but was no different when they referred to PCPs (4 ± 4 mm Hg, p = 0.31). Specialist-treated patrons received more BP medication and different classes of medication than PCP-treated patrons. In conclusion, the barber-based intervention-if connected directly to specialty-level medical care-could have a large public health impact on hypertensive disease in black men.

Aortic Augmentation Index is Independently Associated With N-Terminal Pro B-type Natriuretic Peptide in Patients With Peripheral Arterial Disease

Objectives:

To investigate the relationship of aortic augmentation index (AIx) with N-terminal pro B-type natriuretic peptide (NTproBNP) plasma levels in patients with peripheral arterial disease (PAD) with normal left ventricular (LV) function.

Methods:

Totally, 31 patients (23 males, mean age 65 ± 7.4) with a confirmed diagnosis of PAD of the lower limbs (ankle–brachial pressure index [ABPI] <0.90 in at least 1 leg) were enrolled in this study. All patients underwent pulse wave analysis by applanation tonometry of the radial artery using the SphygmoCor system and had a measurement of plasma NTproBNP levels.

Results:

Patients had a mean resting ABPI of 0.62 ± 0.19 and a mean AIx 32.6% ± 6.9. Median (interquartile range) NTproBNP plasma level was 75 (44-210) pg/mL. In a univariate analysis which included age, brachial systolic blood pressure (BSBP), brachial diastolic blood pressure (BDBP), ejection duration index (ED%), heart rate (HR), and NTproBNP, aortic AIx was significantly associated (Spearman rho) with NTproBNP, HR, and ED% ( r = .49, P = .006; r = −.72, P = .000, and r = −.42, P = .02, respectively). Multivariate linear regression analysis showed that AIx was associated with NTproBNP (β = 0.38, P = .02) independent of gender, HR, ED%, and use of β-blockers. N-terminal pro B-type natriuretic peptide explained 8% of the variance in aortic AIx, whereas HR explained 15% of the variance.

Conclusion:

In patients with PAD with normal LV systolic function, AIx is independently associated with NTproBNP. Structural changes in the myocardium might occur due to increased LV afterload as a result of increased wave reflections and arterial stiffness due to atherosclerosis leading to an increase in NTproBNP plasma levels.

The Vicorder device compared with SphygmoCor in the assessment of carotid-femoral pulse wave velocity in patients with peripheral arterial disease

To assess the reliability and reproducibility of the Vicorder's carotid-femoral pulse wave velocity (cfPWV) measurements in patients with peripheral arterial disease (PAD) and to compare between cfPWV measurements obtained using the Vicorder with those obtained using the SphygmoCor device as a reference. Some 30 patients with PAD (23 men, mean age 64.9±7.5) underwent cfPWV measurement twice by a single investigator during one visit using the Vicorder and the SphygmoCor according to the manufacturer's instructions. Intra-rater reproducibility for each device was assessed using intraclass correlation coefficients (ICC) and Bland-Altman method. The latter was also used to compare between the two devices. The mean difference (s.d.) between repeated measurements was 0.03±0.92 m s(-1), P=0.85 and 0.01±0.54 m s(-1), P=0.91 for the SphygmoCor and Vicorder, respectively. Measurements of cfPWV were highly reproducible using both devices (ICC=0.94 and 0.92, for the Vicorder and SphygmoCor, respectively). Limits of Agreement using the Bland-Altman method were -1.07 to 1.09 m s(-1) and -1.79 to 1.85 m s(-1) for the Vicorder and the SphygmoCor, respectively. Bland-Altman plots indicated that 90% of the cfPWV measurements using the Vicorder and 93% of the measurements using the SphygmoCor fell within two s.d.s of the mean difference. Transit time (TT) differed significantly between the two devices (mean difference 30±9.2 m s, P<0.001), with the Vicorder recording higher values. Nevertheless, the two devices recorded nearly similar cfPWV measurements (mean difference -0.69±1.6 m s(-1), P=0.02) with 97% of cfPWV values falling within two s.d. values of the mean difference on Bland-Altman plot. Both devices generated highly reproducible cfPWV measurements in patients with PAD and were in good agreement when compared with each other. However, the discrepancy in TT between the two devices lead to the Vicorder producing lower values of cfPWV at high values produced by the SphygmoCor.

The effect of dairy consumption on blood pressure in mid-childhood: CAPS cohort study

BACKGROUND/OBJECTIVES

It has been postulated that a higher dairy consumption may affect blood pressure regulation. The aim of this study was to examine the association between dairy consumption and blood pressure in mid-childhood.

SUBJECTS/METHODS

Subjects (n = 335) were participants of a birth cohort at high risk of asthma with information on diet at 18 months and blood pressure at 8 years. Multivariate analyses were used to assess the association of dairy consumption (serves) and micronutrient intakes (mg). In a subgroup of children (n = 201), dietary intake was also measured at approximately 9 years.

RESULTS

Children in the highest quintile of dairy consumption at 18 months had lower systolic blood pressure (SBP) and diastolic blood pressure (DBP) at 8 years (2.5 mm Hg, P=0.046 and 1.9 mm Hg, P = 0.047, respectively) than those in the lowest quintiles. SBP was lowest among children in the highest quintiles of calcium, magnesium and potassium intakes. Significant negative linear trends were observed between SBP and intakes of dairy serves, calcium, magnesium and potassium. Furthermore, SBP and DBP were lowest in the group of children that consumed at least two dairy serves at both 18 months and the follow-up dietary data collection at 9 years, compared with all other children (SBP 98.7 vs 101.0 mm Hg, P = 0.07; and DBP 56.5 vs 59.3 mm Hg, P = 0.006, respectively).

CONCLUSION

These results are consistent with a protective effect of dairy consumption in childhood on blood pressure at age 8 years.

Snoring is not associated with adverse effects on blood pressure, arterial structure or function in 8-year-old children: the Childhood Asthma Prevention Study (CAPS)

AIMS

To study the association between childhood snoring and cardiovascular risk factors.

METHODS

Cross-sectional analyses of a population-based birth cohort, who had been participants in a randomised controlled trial of interventions to prevent asthma and who were assessed at age 8 years. The presence and frequency of snoring were assessed by parent-completed questionnaire. We measured a wide range of cardiovascular function markers including non-fasting serum lipoproteins, blood pressure, high-sensitivity C-reactive protein, carotid artery intima media thickness (by ultrasound), brachial pulse wave velocity and augmentation index (by applanation tonometry).

RESULTS

Of 409 children whose snoring status was assessed at age 8 years, 321 had lipid and 386 had arterial structure and function measurements. Snoring was not independently associated with blood pressure, carotid artery intima media thickness or measures of arterial stiffness (all P > 0.05). Increasing snoring frequency was independently associated with lower high-density lipoprotein cholesterol (-0.032 g/dL per step, 95% confidence interval -0.060 to -0.003), although the difference in high-density lipoprotein between snorers and non-snorers was not significant (P = 0.052). An association of snoring frequency with brachial pulse wave velocity differed according to body mass index (P = 0.03) and was the reverse of that expected.

CONCLUSIONS

Parentally reported snoring was not independently associated with adverse measurements of metabolic markers, vascular structure or function in 8-year-old children. Parental reports of snoring may be below the treatment threshold without additional diagnosis via sleep studies.

Maternal cigarette smoking is associated with reduced high-density lipoprotein cholesterol in healthy 8-year-old children

AIMS

Smoking in pregnancy is common. Its effects on lipoprotein levels and arterial structure in childhood are not well characterized. We aimed to determine the effects of maternal smoking in pregnancy on lipoprotein levels and arterial wall thickness in healthy pre-pubertal children.

METHODS AND RESULTS

A community-based longitudinal study with prospective ascertainment of exposure to smoking in pregnancy and environmental tobacco smoke (ETS) since birth and then lipoprotein and arterial measurements at age 8 years. In 616 newborn infants (gestation >36 weeks and birth weight >2.5 kg) data were collected prospectively by questionnaire on smoking in pregnancy and ETS exposure in childhood. At age 8-years, 405 of the children had measurements of lipoproteins, blood pressure (BP) and carotid intima-media thickness. Children born to mothers who smoked in pregnancy had lower HDL cholesterol [1.32 vs. 1.50 mmol/L, 95% confidence interval (CI) for difference -0.28 to -0.08, P = 0.0005], higher triglycerides (1.36 vs. 1.20 mmol/L, 95% CI for ratio 1.01-1.30, P = 0.04) and higher systolic BP (102.1 vs. 99.9 mmHg, 95% CI for difference 0.6-3.8, P = 0.006). After adjustment for maternal passive smoking, post-natal ETS exposure, gender, breast feeding duration, physical inactivity, and adiposity, smoking in pregnancy remained significantly associated with lower HDL cholesterol (difference = -0.22 mmol/L, 95% CI -0.36 to -0.08, P = 0.003) but not with higher systolic BP. Neither smoking in pregnancy nor post-natal ETS exposure was associated with alterations of carotid artery wall thickness.

CONCLUSION

Smoking in pregnancy is independently associated with significantly lower HDL cholesterol in healthy 8-year-old children.

No elevated plasma catecholamine levels during sleep in newly diagnosed, untreated hypertensives

The sympatho-adrenergic system is highly involved in regulating sleep, wake and arousal states, and abnormalities in this system are regarded as a key factor in the development and progression of arterial hypertension. While hypertension is associated with a hyperadrenergic state during wakefulness, the effect of hypertension on plasma-catecholamine levels during sleep is not yet known. Twelve young participants with newly diagnosed, untreated hypertension and twelve healthy controls slept for 7 hours in the sleep laboratory. Before and after sleep, subjects rested in a supine position for 3-h periods of wakefulness. We sampled blood at a fast rate (1/10 min) and monitored blood pressure and heart rate continuously. We show that plasma NE and E levels did not differ between hypertensives and normotensive during sleep as well as before and after sleep. Blood pressure was higher in hypertensives, reaching the largest group difference in the morning after sleep. Unlike in the normotensives, in the hypertensive participants the morning rise in blood pressure did not correlate with the rise in catecholamine levels at awakening. Our results suggest that hypertension in its early stages is not associated with a strong hyperadrenergic state during sleep. In showing a diminished control of blood pressure through sympatho-adrenergic signals in hypertensive participants, our data point towards a possible involvement of dysfunctional sleep-related blood pressure regulation in the development of hypertension.

Severe obesity is associated with impaired arterial smooth muscle function in young adults

The degree of arterial dilatation induced by exogenous nitrates (nitrate-mediated dilatation, NMD) has been similar in obese and normal-weight adults after single high-dose glyceryl trinitrate (GTN). We examined whether NMD is impaired in obesity by performing a GTN dose-response study, as this is a potentially more sensitive measure of arterial smooth muscle function. In this cross-sectional study, subjects were 19 obese (age 31.0 ± 1.2 years, 10 male, BMI 44.1 ± 2.1) and 19 age- and sex-matched normal-weight (BMI 22.4 ± 0.4) young adults. Blood pressure (BP), triglycerides, high-density lipoprotein (HDL), and low-density lipoprotein (LDL)-cholesterol, glucose, insulin, high-sensitivity C-reactive protein (hs-CRP), carotid intima-media thickness (CIMT), and flow-mediated dilatation (FMD) were measured. After incremental doses of GTN, brachial artery maximal percent dilatation (maximal NMD) and the area under the dose-response curve (NMD AUC) were calculated. Maximal NMD (13.4 ± 0.9% vs. 18.3 ± 1.1%, P = 0.002) and NMD AUC (54,316 ± 362 vs. 55,613 ± 375, P = 0.018) were lower in obese subjects. The obese had significantly higher hs-CRP, insulin, and CIMT and lower HDL-cholesterol. Significant bivariate associations existed between maximal NMD or NMD AUC and BMI-group (r = -0.492, P = 0.001 or r = -0.383, P = 0.009), hs-CRP (r = -0.419, P = 0.004 or r = -0.351, P = 0.015), and HDL-cholesterol (r = 0.374, P = 0.01 or r = 0.270, P = 0.05). On multivariate analysis, higher BMI-group remained as the only significant determinant of maximal NMD (r² = 0.242, β = -0.492, P = 0.002) and NMD AUC (r² = 0.147, β = -0.383, P = 0.023). In conclusion, arterial smooth muscle function is significantly impaired in the obese. This may be important in their increased cardiovascular risk.

Accuracy of oscillometric devices in children and adults

Clinical validation of blood pressure oscillometric devices are almost exclusively conducted in adults. Because oscillometric devices are used in children, it is critical to assess their accuracy also in this population. We compared blood pressure readings using an oscillometric automated device (Dinamap XL, model CR9340) with readings obtained with the mercury auscultatory method in children and adults. Blood pressure was measured in 30 children (15 boys and 15 girls; 9.5+/-1.0 years old) and their parents (25 mothers and 15 fathers; 41.0+/-5.0 years old). In children, mean difference (+/-SD) in systolic blood pressure (DeltaBP) readings (oscillometric-auscultatory) was +0.6+/-4.7 mmHg (range: -10 to +11); mean diastolic DeltaBP was 21.3+/-7.5 mmHg (range: -18 to +19) and decreased with increasing diastolic BP. In adults, mean systolic DeltaBP was +0.4+/-5.2 mmHg (range: -12 to +15) and mean diastolic DeltaBP was -5.2+/-6.0 mmHg (range: -25 to +8) (p<0.001). While the device was not accurate enough to be recommended, our study also shows that the accuracy of blood pressure oscillometric devices can differ between children and adults. Clinical accuracy of oscillometric devices should be tested in the specific populations in whom blood pressure is measured.

Effectiveness of a barber-based intervention for improving hypertension control in black men: the BARBER-1 study: a cluster randomized trial

BACKGROUND

Barbershop-based hypertension (HTN) outreach programs for black men are becoming increasingly common, but whether they are an effective approach for improving HTN control remains uncertain.

METHODS

To evaluate whether a continuous high blood pressure (BP) monitoring and referral program conducted by barbers motivates male patrons with elevated BP to pursue physician follow-up, leading to improved HTN control, a cluster randomized trial (BARBER-1) of HTN control was conducted among black male patrons of 17 black-owned barbershops in Dallas County, Texas (March 2006-December 2008). Participants underwent 10-week baseline BP screening, and then study sites were randomized to a comparison group that received standard BP pamphlets (8 shops, 77 hypertensive patrons per shop) or an intervention group in which barbers continually offered BP checks with haircuts and promoted physician follow-up with sex-specific peer-based health messaging (9 shops, 75 hypertensive patrons per shop). After 10 months, follow-up data were obtained. The primary outcome measure was change in HTN control rate for each barbershop.

RESULTS

The HTN control rate increased more in intervention barbershops than in comparison barbershops (absolute group difference, 8.8% [95% confidence interval (CI), 0.8%-16.9%]) (P = .04); the intervention effect persisted after adjustment for covariates (P = .03). A marginal intervention effect was found for systolic BP change (absolute group difference, -2.5 mm Hg [95% CI, -5.3 to 0.3 mm Hg]) (P = .08).

CONCLUSIONS

The effect of BP screening on HTN control among black male barbershop patrons was improved when barbers were enabled to become health educators, monitor BP, and promote physician follow-up. Further research is warranted.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00325533.

Evaluation scale to assess the accuracy of cuff-less blood pressure measuring devices

OBJECTIVE

The call for early detection of hypertension and cardiac events creates a heavy demand for devices that can be used for blood pressure (BP) monitoring at home and in ambulatory settings. An emerging type of BP monitors without an occluding cuff has drawn great attentions for this application because it is comfortable and capable of providing continuous readings. For the development the cuff-less devices, it is crucial for the clinicians and engineers to joint efforts in establishing an evaluation standard.

METHODS

This study attempts to contribute to its initiation in two ways. First, a new distribution model for measurement differences between the test device and the reference was proposed. We verified the model using evaluation results from 40 devices, of which 80% of the American Association for the Advancement of Medical Instrumentation and British Hypertension Society reporting results were in agreement, as compared with 50%, if the original normal model was used. We further tested a cuff-less device on 85 patients for 999 datasets and found that the differences between the proposed distribution and that of the device were nonsignificant for systolic BP measurements (Kolmogorov-Smirnov = 0.036, P = 0.15). Second, some evaluation scales were studied for their capability to assess the accuracy of cuff-less devices. For mean absolute difference, a map was developed to relate it with the criteria of American Association for the Advancement of Medical Instrumentation, British Hypertension Society, and European Society of Hypertension protocols, on the basis of the proposed distribution model; for mean absolute percentage difference, it is prominent in evaluating devices that have measurement errors often increasing with BP, which is an issue has not been fully explored in existing standards.

CONCLUSION

This study focused on the statistical aspect of establishing standard to assess the accuracy of cuff-less BP measuring devices. The results of our study on the validation reports of various cuff-based devices and an experimental study on a cuff-less device showed that the t4 distribution is better than the normal distribution in portraying the underlying error distribution of both kinds of devices. Moreover, based on both the theoretical and experimental studies, mean absolute difference or mean absolute percentage difference is recommended as continuous scale to assess the accuracy of cuff-less devices for their own distinctive advantages.

Dietary supplementation with n-3 polyunsaturated fatty acids in early childhood: effects on blood pressure and arterial structure and function at age 8 y

BACKGROUND

n-3 Fatty acid supplementation in adults results in cardiovascular benefits. However, the cardiovascular effects of n-3 supplementation in early childhood are unknown.

OBJECTIVE

The objective was to evaluate blood pressure (BP) and arterial structure and function in 8-y-old children who had participated in a randomized controlled trial of dietary n-3 and n-6 modification over the first 5 y of life.

DESIGN

The children (n = 616; 49% girls) were randomly assigned antenatally to active (n = 312; increase in n-3 intake and decrease in n-6 intake) or control (n = 304) diet interventions implemented from the time of weaning or introduction of solids until 5 y of age. At age 8.0 +/- 0.1 y, BP, carotid intima-media thickness, carotid artery distensibility, augmentation index, and brachial pulse wave velocity were measured in 405 of these children. Venous blood was collected for measurement of plasma fatty acids, lipoproteins, high-sensitivity C-reactive protein, and asymmetric dimethylarginine. Plasma fatty acid concentrations were also assessed during the intervention.

RESULTS

Plasma concentrations of n-3 fatty acids were higher and of n-6 were lower in the active than in the control diet group at 18 mo and 3 and 5 y (P < 0.0001). Concentrations of n-3 and n-6 fatty acids were similar at 8 y. At 8 y of age, no significant differences were found in BP, carotid intima-media thickness, carotid artery distensibility, augmentation index, asymmetric dimethylarginine, high-sensitivity C-reactive protein, or lipoproteins between diet groups.

CONCLUSION

A dietary supplement intervention to increase n-3 and decrease n-6 intakes from infancy until 5 y does not result in significant improvements in arterial structure and function at age 8 y. This trial was registered at the Australian Clinical Trials Registry as ACTRN012605000042640.

HDL-Cholesterol, Blood Pressure, and Asymmetric Dimethylarginine Are Significantly Associated With Arterial Wall Thickness in Children

Objective— Atherosclerosis is found at autopsy in the arteries of adolescents and young adults. Arterial wall thickening may be assessed in vivo by ultrasound measurement of the carotid intima media thickness (CIMT), a marker of subclinical atherosclerosis. As the determinants of arterial wall thickness in childhood are unknown, we assessed the influence of cardiovascular risk factors on CIMT in 8-year-old children.

Methods and Results— A community-based sample of 405 children (age 8.0±0.1 years, 49% girls) had anthropometry, family history, blood pressure (BP), and CIMT measured. A blood sample was collected for HDL and non-HDL cholesterol, apolipoproteins A1 and B, high-sensitivity C-reactive protein, bilirubin, and asymmetric dimethylarginine (ADMA, an endogenous nitric oxide inhibitor). CIMT was significantly associated with systolic BP ( r =0.17, P <0.001), diastolic BP ( r =0.10, P =0.04), HDL ( r =−0.13, P =0.02), and ADMA ( r =0.18, P =0.001). CIMT was significantly higher in children with premature parental CHD (0.63±0.07 versus 0.59±0.06 mm, P =0.03). On multivariate analysis, HDL (β coefficient=−0.02, P =0.04), ADMA (β coefficient=0.05, P <0.001), and systolic BP (β coefficient=0.001, P =0.003) were significantly and independently associated with CIMT.

Conclusions— Lower HDL-cholesterol, higher levels of ADMA, and systolic BP are significantly associated with greater arterial wall thickness in early childhood.

Gender differences in the relationship between heart rate control and adiposity in young children: a cross-sectional study (EarlyBird 33)

BACKGROUND

The role of the autonomic nervous system in the complex link between insulin resistance and cardiovascular risk remains unclear. Increased sympathetic nervous system activity has been implicated in the pathophysiology of insulin resistance but is confounded by a number of factors.

METHODS

We have therefore examined the relationship among cardiac autonomic control, insulin resistance, habitual physical activity, resting energy expenditure (REE), and anthropometric variables in a subset (107 boys, 101 girls, age 9 +/- 0.25 yr) of the EarlyBird cohort. Cardiac autonomic activity was assessed using time domain and power spectral density analysis methods of heart rate variability. Insulin resistance was measured using homeostasis model assessment of insulin resistance (HOMA2-IR).

RESULTS

Girls, in comparison to boys, showed significantly higher resting heart rate and lower systolic blood pressure (BP); were more insulin resistant; undertook less physical activity, and had lower fat-free mass and REE. Increasing fasting insulin and increasing insulin resistance were associated with increasing BP.

CONCLUSION

The data suggest early gender differences in predictors of cardiac autonomic control. Pubertal staging was not undertaken in this study, and we plan to evaluate this in future studies to further clarify these associations.

Trends in high blood pressure prevalence in Greek adolescents

A school-based screening with anthropometric and blood pressure (BP) measurements was performed in adolescents aged 12-17 years in the island of Samos, Greece, in 2004 and also in 2007. A total of 446 adolescents were included in the analysis in 2004 and 558 in 2007. The 2007 study population had higher levels of body mass index (BMI) (P<0.05) and systolic and diastolic BP (P<0.001), compared with 2004. The prevalence of high BP was 16.1% in 2004 and 22.9% in 2007 (P<0.01 for difference). Mean age-, sex- and BMI-adjusted BP increase was 4.1/10.5 mm Hg (systolic/diastolic). In multivariate analysis, BMI, male gender and age, but also modifiable factors (lack of physical activity, breakfast skipping, smoking and low milk consumption) were associated with increased BP levels in the study population. These data indicate that further to BMI, other factors such as adverse lifestyle and dietary habits appear to be associated with elevated BP levels in adolescents. Moreover, rising trends seem to characterize the prevalence of high BP.