Comparison of the oscillometric blood pressure monitor (BPM-100(Beta) ) with the auscultatory mercury sphygmomanometer

Individual versus integration of multiple components of central blood pressure and aortic stiffness in predicting cardiovascular mortality in end-stage renal diseases

Aortic stiffness, measured by carotid-femoral pulse wave velocity (PWV), is a predictor of cardiovascular (CV) mortality in patients with end-stage renal disease (ESRD). Aortic stiffness increases aortic systolic and pulse pressures (cSBP, cPP) and augmentation index adjusted for a heart rate of 75 beats per minute (AIx@75). In this study, we examined if the integration of multiple components of central blood pressure and aortic stiffness (ICPS) into risk score categories could improve CV mortality prediction in ESRD. In a prospective cohort of 311 patients with ESRD on dialysis who underwent vascular assessment at baseline, 118 CV deaths occurred after a median follow-up of 3.1 years. The relationship between hemodynamic parameters and CV mortality was analyzed through Kaplan-Meier and Cox survival analysis. ICPS risk score from 0 to 5 points were calculated from points given to tertiles, and were regrouped into three risk categories (Average, High, Very-High). A strong association was found between the ICPS risk categories and CV mortality (High risk HR = 2.20, 95% CI: 1.05-4.62, P = 0.036); Very-High risk (HR = 4.44, 95% CI: 2.21-8.92, P < 0.001) as compared to the Average risk group. The Very-High risk category remained associated with CV mortality (HR = 3.55, 95% CI: 1.37-9.21, P = 0.009) after adjustment for traditional CV risk factors as compared to the Average risk group. While higher C-statistics value of ICPS categories (C: 0.627, 95% CI: 0.578-0.676, P = 0.001) was not statistically superior to PWV, cPP or AIx@75, the use of ICPS categories resulted in a continuous net reclassification index of 0.56 (95% CI: 0.07-0.99). In conclusion, integration of multiple components of central blood pressure and aortic stiffness may potentially be useful for better prediction of CV mortality in this cohort.

Salat Dhuha Improves Haemodynamic: A Randomized Controlled Study

BACKGROUND: The prevalence of hypertension increases with age, more than 1 in every two elderly have hypertension, dominated by women. The primary prevention of hypertension is a worldwide public health concern. Salat Dhuha is a moderate-intensity physical activity. Salat with a two-movement cycle (rakaat) demonstrated improved hemodynamic in adults. AIM: Our study purpose was to asses the effects of 2 and 8 rakaats of Salat Dhuha in improving systolic and diastolic blood pressure and heart rate in healthy elderly women. METHODS: Elderly women in the Senior Care Residence (aged 60–74 years) participated in a 6-week controlled study. We completed a formal physical, clinical, and blood assessments before admission. Participants with a history of hypertension were excluded from the study. The participants were randomized into 2 groups, i.e., “8 rakaats group” (n = 13) and “2 rakaats group” (n = 13) of Salat Dhuha. Two participants dropped out from the present study. At baseline and at the end of 6 weeks study period, blood pressure and heart rate were recorded. All data obtained were statistically analyzed. RESULTS: Both groups demonstrated the benefits of Salat Dhuha in improving hemodynamic parameters (systolic and diastolic blood pressure and heart rate). However, the reduction of systolic blood pressure in the “2 rakaats group” (2.16 mmHg) was less than in the “8 rakaats group” (5.50 mmHg), the reduction of diastolic blood pressure in the “2 rakaats group” (0.75 mmHg) was less than the “8 rakaats group” (2.41 mmHg) and the reduction of heart rate in “2 rakaats group” (2.08 bpm) was less than the “8 rakaats group” (6.08 bpm). All differences were statistically significant (p < 0.05). CONCLUSION: This study demonstrated that the Salat Dhuha has a significant potential in improving hemodynamic parameters for elderly women which the more frequent rakaat will give more benefit than less frequent rakaat.

Preparation of fluorescent bimetallic silver/copper nanoparticles and their utility of dual-mode fluorimetric and colorimetric probe for Hg2

A dual-mode colorimetric and fluorimetric probe was successfully established based on silver/copper bimetallic nanoparticles (AgCu-BNPs). The AgCu-BNPs were confirmed as individually bimetallic nanoparticles with a mean size of 7.7 ± 0.2 nm, as characterized by high resolution transmission electron microscopy. Intriguingly, the AgCu-BNPs possess both surface plasmon resonances (SPR) and fluorescence emission. AgCu-BNPs emanate bright blue fluorescence with optical emission centered at 442 nm with high quantum yield of 30.3%, and AgCu-BNPs were attenuated or even quenched by Hg²⁺ via both static and dynamic quenching, coincidently accompanied by a visible color change, which endow AgCu-BNPs a unique utility as dual-mode colorimetric and fluorimetric probes. The detection limits as low as 89 nM and 9 nM were determined by dual-mode of AgCu-BNPs, respectively. The recovery rates in real samples were found to be 97.3-118.8%, and 89.5-112.7% by colorimetric and fluorescent methods separately, demonstrates the good environmental tolerance of the dual-mode probe.

A clinical set-up for noninvasive blood pressure monitoring using two photoplethysmograms and based on convolutional neural networks

Blood pressure is a reliable indicator of many cardiac arrhythmias and rheological problems. This study proposes a clinical set-up using conventional monitoring systems to estimate systolic and diastolic blood pressures continuously based on two photoplethysmogram signals (PPG) taken from the earlobe and toe. Several amendments were applied to conventional clinical monitoring devices to construct our project plan. We used two monitors to acquire two PPGs, one ECG, and invasive blood pressure as the reference to evaluate the estimation accuracy. One of the most critical requirements was the synchronization of the acquired signals that was accomplished by using ECG as the time reference. Following data acquisition and preparation procedures, the performance of each PPG signal alone and together was investigated using deep convolutional neural networks. The proposed architecture was evaluated on 32 records acquired from 14 patients after cardiovascular surgery. The results showed a better performance for toe PPG in comparison with earlobe PPG. Moreover, they indicated the algorithm accuracy improves if both signals are applied together to the network. According to the British Hypertension Society standards, the results achieved grade A for both blood pressure measurements. The mean and standard deviation of estimation errors were +0.3 ± 4.9 and +0.1 ± 3.2 mmHg for systolic and diastolic BPs, respectively. Since the method is based on conventional monitoring equipment and provides a high estimation consistency, it can be considered as a possible alternative for inconvenient invasive BP monitoring in clinical environments.

Exosomal miRNAs in urine associated with children's cardiorenal parameters: a cross-sectional study

Aims:

The authors sought to examine associations between urinary exosomal miRNAs (exo-miRs), emerging biomarkers of renal health, and cardiorenal outcomes in early childhood.

Materials & methods:

The authors extracted exo-miRs in urine from 88 healthy Mexican children aged 4–6 years. The authors measured associations between 193 exo-miRs and cardiorenal outcomes: systolic/diastolic blood pressure, estimated glomerular filtration rate and urinary sodium and potassium levels. The authors adjusted for age, sex, BMI, socioeconomic status, indoor tobacco smoke exposure and urine specific gravity.

Results:

Multiple exo-miRs were identified meeting a false discovery rate threshold of q < 0.1. Specifically, three exo-miRs had increased expression with urinary sodium, 17 with urinary sodium-to-potassium ratio and one with decreased estimated glomerular filtration rate.

Conclusions:

These results highlight urinary exo-miRs as early-life biomarkers of children's cardiorenal health.

Identifying critical windows of prenatal particulate matter (PM2.5) exposure and early childhood blood pressure

BACKGROUND

Exposure to air pollution is associated with increased blood pressure (BP) in adults and children. Some evidence suggests that air pollution exposure during the prenatal period may contribute to adverse cardiorenal health later in life. Here we apply a distributed lag model (DLM) approach to identify critical windows that may underlie the association between prenatal particulate matter ≤ 2.5 μm in diameter (PM_2.5) exposure and children's BP at ages 4-6 years.

METHODS

Participants included 537 mother-child dyads enrolled in the Programming Research in Obesity, GRowth Environment, and Social Stress (PROGRESS) longitudinal birth cohort study based in Mexico City. Prenatal daily PM_2.5 exposure was estimated using a validated satellite-based spatio-temporal model and BP was measured using the automated Spacelabs system with a sized cuff. We used distributed lag models (DLMs) to examine associations between daily PM_2.5 exposure and systolic and diastolic BP (SBP and DBP), adjusting for child's age, sex and BMI, as well as maternal education, preeclampsia and indoor smoking report during the second and third trimester, seasonality and average postnatal year 1 PM_2.5 exposure.

RESULTS

We found that PM_2.5 exposure between weeks 11-32 of gestation (days 80-226) was significantly associated with children's increased SBP. Similarly, PM_2.5 exposure between weeks 9-25 of gestation (days 63-176) was significantly associated with increased DBP. To place this into context, a constant 10 μg/m³ increase in PM_2.5 sustained throughout this critical window would predict a cumulative increase of 2.6 mmHg (CI: 0.5, 4.6) in SBP and 0.88 mmHg (CI: 0.1, 1.6) in DBP at ages 4-6 years. In a stratified analysis by sex, this association persisted in boys but not in girls.

CONCLUSIONS

Second and third trimester PM_2.5 exposure may increase children's BP in early life. Further work investigating PM_2.5 exposure with BP trajectories later in childhood will be important to understanding cardiorenal trajectories that may predict adult disease. Our results underscore the importance of reducing air pollution exposure among susceptible populations, including pregnant women.

Using out-of-office blood pressure measurements in established cardiovascular risk scores: a secondary analysis of data from two blood pressure monitoring studies

BACKGROUND

Blood pressure (BP) measurement is increasingly carried out through home or ambulatory monitoring, yet existing cardiovascular risk scores were developed for use with measurements obtained in clinics.

AIM

To describe differences in cardiovascular risk estimates obtained using ambulatory or home BP measurements instead of clinic readings.

DESIGN AND SETTING

Secondary analysis of data from adults aged 25-84 years in the UK and the Netherlands without prior history of cardiovascular disease (CVD) in two BP monitoring studies: the Blood Pressure in different Ethnic groups (BP-Eth) study and the Home versus Office blood pressure MEasurements: Reduction of Unnecessary treatment Study (HOMERUS).

METHOD

The primary comparison was Framingham risk calculated using BP measured as in the Framingham study or daytime ambulatory BP measurements. Statistical significance was determined using non-parametric tests.

RESULTS

In 442 BP-Eth patients (mean age = 58 years, 50% female [n = 222]) the median absolute difference in 10-year Framingham cardiovascular risk calculated using BP measured as in the Framingham study or daytime ambulatory BP measurements was 1.84% (interquartile range [IQR] 0.65-3.63, P = 0.67). In 165 HOMERUS patients (mean age = 56 years, 46% female) the median absolute difference in 10-year risk for daytime ambulatory BP was 2.76% (IQR 1.19-6.39, P<0.001) and only 8 out of 165 (4.8%) of patients were reclassified.

CONCLUSION

Estimates of cardiovascular risk are similar when calculated using BP measurements obtained as in the risk score derivation study or through ambulatory monitoring. Further research is required to determine if differences in estimated risk would meaningfully influence risk score accuracy.

Prenatal lead exposure modifies the effect of shorter gestation on increased blood pressure in children

BACKGROUND

High blood pressure (BP) in childhood is frequently renal in origin and a risk factor for adult hypertension and cardiovascular disease. Shorter gestations are a known risk factor for increased BP in adults and children, due in part to a nephron deficit in children born preterm. As nephrogenesis is incomplete until 36 weeks gestation, prenatal lead exposure occurring during a susceptible period of renal development may contribute to programming for later life renal disease. The relationship between shorter gestation and children's BP has not yet been explored to identify i) critical windows using nonlinear piecewise models or ii) combined with other early life risk factors such as prenatal lead exposure.

OBJECTIVES

(1) To evaluate the nonlinear relationship between lower gestational age and childhood BP measured at 4-6 years of age, and (2) to investigate modification by prenatal lead exposure.

METHODS

In a prospective longitudinal birth cohort, we assessed 565 children between 4 and 6 years of age (mean: 4.8 years) in the PROGRESS cohort in Mexico City, Mexico. Gestational age at delivery was calculated using maternal report of last menstrual period (LMP) and confirmed with Capurro physical examination at birth. We measured pregnant women's blood lead levels (BLLs) in the second trimester via inductively coupled plasma-mass spectrometry and children's BP using an automated device. We performed both linear and nonlinear piecewise regression analyses to examine associations of gestational age with children's BP adjusting for children's age, sex, height, prenatal exposure to smoke, and maternal socioeconomic status. We stratified to assess modification by prenatal lead exposure, and used a data-adaptive approach to identify a lead cutpoint.

RESULTS

Maternal second trimester BLLs ranged from 0.7 to 17.8 μg/dL with 112 (20%) women above the CDC guideline level of 5 μg/dL. In adjusted linear regression models, a one week reduction in gestational age was associated with a 0.5 mm Hg (95%CI: 0.2, 0.8) increase in SBP and a 0.4 mm Hg (95%CI 0.1, 0.6) increase in DBP. Our nonlinear models suggested evidence for different magnitude estimates on either side of an estimated join-point at 35.9 weeks' gestation, but did not reach statistical significance. However, when stratified by prenatal lead exposure, we identified a cutpoint lead level of concern of 2.5 μg/dL that suggested an interaction between gestational age and blood lead. Specifically, for BLLs ≥ 2.5 μg/dL, SBP was 1.6 (95%CI: 0.3, 2.9) mm Hg higher per each week reduction in gestational age among children born before 37.0 weeks; and among children born after 37.0 weeks, this relationship was attenuated yet remained significant [β: 0.9, 95%CI (0.2, 1.6)]. At BLLs below 2.5 μg/dL, there was no appreciable association between lower gestational age and SBP.

CONCLUSIONS

Our findings suggest that shorter gestation combined with higher prenatal lead exposure contributes to a higher risk of increased SBP at 4-6 years of age, particularly among infants born <37 weeks gestation. Our results underscore the importance of preventing prenatal lead exposure - even levels as low as 2.5 μg/dL - especially among pregnant women at risk for preterm birth. Given that high BP in childhood is a risk factor for adult hypertension and cardiovascular disease later in life, these results may have implications that extend across the life span.

Sources of inaccuracy in the measurement of adult patients' resting blood pressure in clinical settings: a systematic review

BACKGROUND

To interpret blood pressure (BP) data appropriately, healthcare providers need to be knowledgeable of the factors that can potentially impact the accuracy of BP measurement and contribute to variability between measurements.

METHODS

A systematic review of studies quantifying BP measurement inaccuracy. Medline and CINAHL databases were searched for empirical articles and systematic reviews published up to June 2015. Empirical articles were included if they reported a study that was relevant to the measurement of adult patients' resting BP at the upper arm in a clinical setting (e.g. ward or office); identified a specific source of inaccuracy; and quantified its effect. Reference lists and reviews were searched for additional articles.

RESULTS

A total of 328 empirical studies were included. They investigated 29 potential sources of inaccuracy, categorized as relating to the patient, device, procedure or observer. Significant directional effects were found for 27; however, for some, the effects were inconsistent in direction. Compared with true resting BP, significant effects of individual sources ranged from -23.6 to +33 mmHg SBP and -14 to +23 mmHg DBP.

CONCLUSION

A single BP value outside the expected range should be interpreted with caution and not taken as a definitive indicator of clinical deterioration. Where a measurement is abnormally high or low, further measurements should be taken and averaged. Wherever possible, BP values should be recorded graphically within ranges. This may reduce the impact of sources of inaccuracy and reduce the scope for misinterpretations based on small, likely erroneous or misleading, changes.

Measurement of blood pressure for the diagnosis and management of hypertension in different ethnic groups: one size fits all

Background

Hypertension is a major risk factor for cardiovascular disease and prevalence varies by ethnic group. The diagnosis and management of blood pressure are informed by guidelines largely based on data from white populations. This study addressed whether accuracy of blood pressure measurement in terms of diagnosis of hypertension varies by ethnicity by comparing two measurement modalities (clinic blood pressure and home monitoring) with a reference standard of ambulatory BP monitoring in three ethnic groups.

Methods

Cross-sectional population study (June 2010 - December 2012) with patients (40–75 years) of white British, South Asian and African Caribbean background with and without a previous diagnosis of hypertension recruited from 28 primary care practices. The study compared the test performance of clinic BP (using various protocols) and home-monitoring (1 week) with a reference standard of mean daytime ambulatory measurements using a threshold of 140/90 mmHg for clinic and 135/85 mmHg for out of office measurement.

Results

A total of 551 participants had complete data of whom 246 were white British, 147 South Asian and 158 African Caribbean. No consistent difference in accuracy of methods of blood pressure measurement was observed between ethnic groups with or without a prior diagnosis of hypertension: for people without hypertension, clinic measurement using three different methodologies had high specificity (75–97%) but variable sensitivity (33–65%) whereas home monitoring had sensitivity of 68–88% and specificity of 64–80%. For people with hypertension, detection of a raised blood pressure using clinic measurements had sensitivities of 34–69% with specificity of 73–92% and home monitoring had sensitivity (81–88%) and specificity (55–65%).

Conclusions

For people without hypertension, ABPM remains the choice for diagnosing hypertension compared to the other modes of BP measurement regardless of ethnicity. Differences in accuracy of home monitoring and clinic monitoring (higher sensitivity of the former; higher specificity of the latter) were also not affected by ethnicity.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-017-0491-8) contains supplementary material, which is available to authorized users.

Aortic–Brachial Pulse Wave Velocity Ratio

Aortic stiffness, a cardiovascular risk factor, depends on the operating mean arterial pressure (MAP). The impact of aortic stiffness on cardiovascular outcomes is proposed to be mediated by the attenuation or the reversal of the arterial stiffness gradient. We hypothesized that arterial stiffness gradient is less influenced by changes in MAP. We aimed to study the relationship between MAP and aortic stiffness, brachial stiffness, and arterial stiffness gradient. In a cross-sectional study of a dialysis cohort (group A, n=304) and a cohort of hypertensive or kidney transplant recipient with an estimated glomerular filtration rate of >45 mL/min/1.73 m 2 (group B, n=114), we assessed aortic and brachial stiffness by measuring carotid–femoral and carotid–radial pulse wave velocities (PWV). We used aortic–brachial PWV ratio as a measure of arterial stiffness gradient. Although there was a positive relationship between MAP and carotid–femoral PWV ( R 2 =0.10 and 0.08; P <0.001 and P =0.003) and MAP and carotid–radial PWV ( R 2 =0.22 and 0.12; P <0.001 and P <0.001), there was no statistically or clinically significant relationship between MAP and aortic–brachial PWV ratio ( R 2 =0.0002 and 0.0001; P =0.8 and P =0.9) in group A and B, respectively. Dialysis status and increasing age increased the slope of the relationship between MAP and cf-PWV. However, we found no modifying factor (age, sex, dialysis status, diabetes mellitus, cardiovascular disease, and class of antihypertensive drugs) that could affect the lack of relationship between MAP and aortic–brachial PWV ratio. In conclusion, these results suggest that aortic–brachial PWV ratio could be considered as a blood pressure–independent measure of vascular aging.

Promoting Cardiovascular Health among Older Adults: A Pilot Study with Community Pharmacists

This project enabled us to develop procedures for organizing and running successful pharmacy blood pressure sessions. The knowledge gained from this pilot was used in the multicentred Community Health Awareness Program (CHAP).

Running blood pressure sessions in community pharmacies and using a multidisciplinary approach, including volunteer health educators and support from public health, was a feasible way to raise awareness of cardiovascular health among the older adults who participated in our project.

This pilot project included pharmacist involvement at several stages, from the planning of the blood pressure sessions and development of the documentation forms, to participation in the pilot and feedback after project completion. With its multidisciplinary approach, the pilot showed that it is feasible for a community pharmacist to be involved in research projects that can benefit patient care and enhance their professional roles.

Predicting out-of-office blood pressure level using repeated measurements in the clinic: an observational cohort study

OBJECTIVES

Identification of people with lower (white-coat effect) or higher (masked effect) blood pressure at home compared to the clinic usually requires ambulatory or home monitoring. This study assessed whether changes in SBP with repeated measurement at a single clinic predict subsequent differences between clinic and home measurements.

METHODS

This study used an observational cohort design and included 220 individuals aged 35-84 years, receiving treatment for hypertension, but whose SBP was not controlled. The characteristics of change in SBP over six clinic readings were defined as the SBP drop, the slope and the quadratic coefficient using polynomial regression modelling. The predictive abilities of these characteristics for lower or higher home SBP readings were investigated with logistic regression and repeated operating characteristic analysis.

RESULTS

The single clinic SBP drop was predictive of the white-coat effect with a sensitivity of 90%, specificity of 50%, positive predictive value of 56% and negative predictive value of 88%. Predictive values for the masked effect and those of the slope and quadratic coefficient were slightly lower, but when the slope and quadratic variables were combined, the sensitivity, specificity, positive and negative predictive values for the masked effect were improved to 91, 48, 24 and 97%, respectively.

CONCLUSION

Characteristics obtainable from multiple SBP measurements in a single clinic in patients with treated hypertension appear to reasonably predict those unlikely to have a large white-coat or masked effect, potentially allowing better targeting of out-of-office monitoring in routine clinical practice.

Comparing Guidelines for Statin Treatment in Canada and the United States

Background

New guidelines for cardiovascular disease risk assessment and statin eligibility have recently been published in the United States by the American College of Cardiology and the American Heart Association (ACC-AHA). It is unknown how these guidelines compare with the Canadian Cardiovascular Society (CCS) recommendations.

Methods and Results

Using data from the Canadian Health Measures Survey 2007–2011, we estimated the cardiovascular disease risk and proportion of the Canadian population, aged 40 to 75 years without cardiovascular disease, who would theoretically be eligible for statin treatment under both the CCS and ACC-AHA guidelines. The survey sample used (n=1975) represented 13.1 million community dwelling Canadians between the ages of 40 and 75 years. In comparing the CVD risk assessment methods, we found that calculated CVD risk was higher based on the CCS guidelines compared with the ACC-AHA guidelines. Despite this, a similar proportion and number of Canadians would be eligible for statin treatment under the 2 sets of recommendations. Some discordance in recommendations was found within subgroups of the population, with the CCS guidelines recommending more treatment for individuals who are younger, with a family history of CVD, or with chronic kidney disease. The ACC-AHA recommend more treatment for people who are older (age 60+ years). These results likely overestimate the treatment rate under both guidelines because, in primary prevention, a clinician–patient discussion must occur before treatment and determines uptake.

Conclusions

Implementing the ACC-AHA lipid treatment guidelines in Canada would not result in an increase in individuals eligible for statin treatment. In fact, the proportion of the population recommended for statin treatment would decrease slightly and be targeted at different subgroups of the population.

Randomized Trial of the Effect of Pharmacist Prescribing on Improving Blood Pressure in the Community: The Alberta Clinical Trial in Optimizing Hypertension (RxACTION)

BACKGROUND

Hypertension control rates remain suboptimal. Pharmacists' scope of practice is evolving, and their position in the community may be ideal for improving hypertension care. We aimed to study the impact of pharmacist prescribing on blood pressure (BP) control in community-dwelling patients.

METHODS AND RESULTS

We designed a patient-level, randomized, controlled trial, enrolling adults with above-target BP (as defined by Canadian guidelines) through community pharmacies, hospitals, or primary care teams in 23 communities in Alberta. Intervention group patients received an assessment of BP and cardiovascular risk, education on hypertension, prescribing of antihypertensive medications, laboratory monitoring, and monthly follow-up visits for 6 months (all by their pharmacist). Control group patients received a wallet card for BP recording, written hypertension information, and usual care from their pharmacist and physician. Primary outcome was the change in systolic BP at 6 months. A total of 248 patients (mean age, 64 years; 49% male) were enrolled. Baseline mean±SD systolic/diastolic BP was 150±14/84±11 mm Hg. The intervention group had a mean±SE reduction in systolic BP at 6 months of 18.3±1.2 compared with 11.8±1.9 mm Hg in the control group, an adjusted difference of 6.6±1.9 mm Hg (P=0.0006). The adjusted odds of patients achieving BP targets was 2.32 (95% confidence interval, 1.17-4.15 in favor of the intervention).

CONCLUSIONS

Pharmacist prescribing for patients with hypertension resulted in a clinically important and statistically significant reduction in BP. Policy makers should consider an expanded role for pharmacists, including prescribing, to address the burden of hypertension.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00878566.

MEthods of ASsessing blood pressUre: identifying thReshold and target valuEs (MeasureBP): a review & study protocol

Despite progress in automated blood pressure measurement (BPM) technology, there is limited research linking hard outcomes to automated office BPM (OBPM) treatment targets and thresholds. Equivalences for automated BPM devices have been estimated from approximations of standardized manual measurements of 140/90 mmHg. Until outcome-driven targets and thresholds become available for automated measurement methods, deriving evidence-based equivalences between automated methods and standardized manual OBPM is the next best solution. The MeasureBP study group was initiated by the Canadian Hypertension Education Program to close this critical knowledge gap. MeasureBP aims to define evidence-based equivalent values between standardized manual OBPM and automated BPM methods by synthesizing available evidence using a systematic review and individual subject-level data meta-analyses. This manuscript provides a review of the literature and MeasureBP study protocol. These results will lay the evidenced-based foundation to resolve uncertainties within blood pressure guidelines which, in turn, will improve the management of hypertension.

Aortic-Brachial Stiffness Mismatch and Mortality in Dialysis Population

We hypothesized that increased aortic stiffness (central elastic artery) combined with a decrease in brachial stiffness (peripheral muscular artery) leads to the reversal of the physiological stiffness gradient (ie, mismatch), promoting end-organ damages through increased forward pressure wave transmission into the microcirculation. We, therefore, examined the effect of aortic-brachial stiffness mismatch on mortality in patients in need of dialysis. In a prospective observational study, aortic-brachial arterial stiffness mismatch (pulse wave velocity ratio) was assessed using carotid-femoral pulse wave velocity divided by carotid-radial pulse wave velocity in 310 adult patients on dialysis. After a median follow-up of 29 months, 146 (47%) deaths occurred. The hazard ratio (HR) for mortality related to PWV ratio in a Cox regression analysis was 1.43 (95% confidence interval [CI], 1.24–1.64; P <0.001 per 1 SD) and was still significant after adjustments for confounding factors, such as age, dialysis vintage, sex, cardiovascular disease, diabetes mellitus, smoking status, and weight (HR, 1.23; 95% CI: 1.02–1.49). The HRs for changes in 1 SD of augmentation index (HR, 1.35; 95% CI, 1.12–1.63), carotid-femoral pulse wave velocity (HR, 1.29; 95% CI, 1.11–1.50), and carotid-radial pulse wave velocity (HR, 0.80; 95% CI, 0.67–0.95) were statistically significant in univariate analysis, but were no longer statistically significant after adjustment for age. In conclusion, aortic-brachial arterial stiffness mismatch was strongly and independently associated with increased mortality in this dialysis population. Further studies are required to confirm these finding in lower-risk groups.

Active vitamin D and accelerated progression of aortic stiffness in hemodialysis patients: a longitudinal observational study

BACKGROUND

We hypothesized that high-dose active vitamin D therapy in the form of alphacalcidol (α-calcidol), used to treat secondary hyperparathyroidism in chronic kidney disease, could lead to vascular calcification and accelerated progression of aortic stiffness.

METHODS

We conducted an observational study in 85 patients on chronic hemodialysis, among which 70 were taking a weekly dose of α-calcidol of <2 µg and 15 were taking a weekly dose of ≥2 µg (pharmacological dose). Parathyroid hormone, 25-hydroxyvitamin D, fibroblast growth factor 23, and α-klotho were determined. Aortic stiffness was assessed by determination of carotid-femoral pulse wave velocity (cf-PWV) at baseline and after a mean follow-up of 1.2 years. A multivariable regression model was used to evaluate the impact of pharmacological dose of α-calcidol on the progression of aortic stiffness.

RESULTS

At baseline, clinical, biological, and hemodynamic parameters were similar. At follow-up, cf-PWV increased more in patients with pharmacological dose of α-calcidol (0.583±2.291 m/s vs. 1.948±1.475 m/s; P = 0.04). After adjustment for changes in mean blood pressure and duration of follow-up, pharmacological dose of α-calcidol was associated with a higher rate of progression of cf-PWV (0.969 m/s; 95% confidence interval = 0.111-1.827; P = 0.03), and this association persisted after further adjustments for parameters of mineral metabolism.

CONCLUSIONS

In this study, pharmacological dose of α-calcidol was associated with accelerated progression of aortic stiffness. This study suggest that the vascular safety of active vitamin D posology may need to be specifically addressed in the treatment of chronic kidney disease-related bone mineral disorder.

The effect of intranasal oxytocin administration on acute cold pressor pain: a placebo-controlled, double-blind, within-participants crossover investigation

BACKGROUND

This study examined the effect of synthetic oxytocin delivered intranasally on acute pain sensitivity using a placebo-controlled, double-blind, within-participant crossover design.

METHODS

Thirty-seven (18 were male) pain-free young adults underwent two laboratory sessions separated by 1 week. Each session consisted of baseline, administration, second baseline, pain, and recovery phases, completed in a fixed order. Participants were given an intransal administration of 40 IU oxytocin or placebo. Blood pressure and heart rate (HR) were measured at 1-minute intervals throughout each phase. Pain was induced by submersing the nondominant hand in cold (2°C) water. Pain threshold, intensity, unpleasantness, and Short-Form McGill Pain Questionnaire-2 pain descriptors were rated immediately after pain testing. Mood was assessed using visual analog scales after baseline, second baseline, and pain phases. The second laboratory session was identical to the first, with the exception that a different nasal spray was administered.

RESULTS

Participants reported lower pain intensity (50.57 [20.94] versus 56.73 [20.12], p = .047), pain unpleasantness (47.00 [27.24] versus 55.78 [22.46], p = .033), and Short-Form McGill Pain Questionnaire-2 pain descriptors (53.38 [31.18] versus 60.92 [31.17], p = .031) and higher pain threshold (45.70 [59.55] versus 38.35 [59.12], p = .040) after oxytocin administration relative to placebo. There was a nasal spray by phase interaction on HR (p = .006). Pain-related increase in HR was attenuated by oxytocin nasal spray. Systolic and diastolic blood pressure increased during pain testing but were unaffected by nasal spray.

CONCLUSIONS

These results suggest that oxytocin can lead to decreased acute pain sensitivity.

Determinants of progression of aortic stiffness in hemodialysis patients: a prospective longitudinal study

Aortic stiffness is associated with increased cardiovascular mortality in patients with chronic kidney disease. However, the rate of progression of arterial stiffness and the role of cardiovascular risk factors in the progression of arterial stiffness has never been established in a longitudinal study. In a prospective, longitudinal, observational study, carotid-femoral pulse wave velocity and carotid-radial pulse wave velocity were assessed in 109 hemodialysis patients at baseline and after a mean follow-up of 1.2 years. We examined the impact of age, atherosclerotic cardiovascular disease, diabetes mellitus, dialysis vintage, and pentosidine (a well-characterized, advanced glycation end products) on the rate of progression of aortic stiffness. The annual rate of changes in carotid-femoral pulse wave velocity and carotid-radial pulse wave velocity were 0.84 m/s per year (95% confidence interval, 0.50-1.12 m/s per year) and -0.66 m/s per year (95% confidence interval, -0.85 to -0.47 m/s per year), respectively. Older subjects, and patients with diabetes mellitus or atherosclerotic cardiovascular disease had higher aortic stiffness at baseline, however, the rate of progression of aortic stiffness was only determined by plasma pentosidine levels (P=0.001). The degree of baseline aortic stiffness was a significant determinant of the regression of brachial stiffness (P<0.001) suggesting that the regression of brachial stiffness occurs in response to central aortic stiffness. These findings suggest that traditional cardiovascular risk factors may play some role in the progression of aortic stiffness before development of advanced chronic kidney disease, and that the enhanced rate of progression of aortic stiffness in chronic kidney disease patients on dialysis are probably determined by more specific chronic kidney disease-related risk factors such as advanced-glycation end products.

Reliability studies of diagnostic methods in Indian traditional Ayurveda medicine: An overview

Recently, a need to develop supportive new scientific evidence for contemporary Ayurveda has emerged. One of the research objectives is an assessment of the reliability of diagnoses and treatment. Reliability is a quantitative measure of consistency. It is a crucial issue in classification (such as prakriti classification), method development (pulse diagnosis), quality assurance for diagnosis and treatment and in the conduct of clinical studies. Several reliability studies are conducted in western medicine. The investigation of the reliability of traditional Chinese, Japanese and Sasang medicine diagnoses is in the formative stage. However, reliability studies in Ayurveda are in the preliminary stage. In this paper, examples are provided to illustrate relevant concepts of reliability studies of diagnostic methods and their implication in practice, education, and training. An introduction to reliability estimates and different study designs and statistical analysis is given for future studies in Ayurveda.

Increasing blood pressure and its associated factors in Canadian children and adolescents from the Canadian Health Measures Survey

BACKGROUND

Canada is facing a childhood obesity epidemic. Elevated blood pressure (BP) is a major complication of obesity. Reports on the impact of excess adiposity on BP in children and adolescents have varied significantly across studies. We evaluated the independent effects of obesity, physical activity, family history of hypertension, and socioeconomic status on BP in a nationally representative sample of children and adolescents.

METHODS

We analysed cross-sectional data for 1850 children aged 6 to 17 years who participated in the Canadian Health Measures Survey, Cycle 1, 2007-2009. Systolic BP (SBP) and diastolic BP (DBP) were age-, sex-, and height-adjusted to z-scores (SBPZ and DBPZ). Body mass index (BMI) z-scores were calculated based on World Health Organization growth standards. Multivariate linear regression was used to evaluate the independent effects of relevant variables on SBPZ and DBPZ.

RESULTS

For most age/sex groups, obesity was positively associated with SBP. Being obese was associated with higher DBP in adolescent boys only. The BP effect of obesity showed earlier in young girls than boys. Obese adolescents were estimated to have an average 7.6 mmHg higher SBP than normal weight adolescents. BMI had the strongest effect on BP among obese children and adolescents. Moderately active adolescent boys had higher SBP (3.9 mmHg) and DBP (4.9 mmHg) than physically active boys. Family history of hypertension showed effects on SBP and DBP in younger girls and adolescent boys. Both family income and parent education demonstrated independent associations with BP in young children.

CONCLUSIONS

Our findings demonstrate the early impact of excess adiposity, insufficient physical activity, family history of hypertension, and socioeconomic inequalities on BP. Early interventions to reduce childhood obesity can, among other things, reduce exposure to prolonged BP elevation and the future risk of cardiovascular disease.

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.

Effects of acute variation of dialysate calcium concentrations on arterial stiffness and aortic pressure waveform

BACKGROUND

Abnormal mineral metabolism in chronic kidney disease plays a critical role in vascular calcification and arterial stiffness. The impact of presently used dialysis calcium concentration (D(Ca)) on arterial stiffness and aortic pressure waveform has never been studied. The aim of the present study is to evaluate, in haemodialysis (HD) patients, the impact of acute modification of D(Ca) on arterial stiffness and central pulse wave profile (cPWP). Method. A randomized Latin square cross-over study was used to evaluate the three different concentrations of D(Ca) (1.00, 1.25 and 1.50 mmol/L) during the second HD of the week for 3 consecutive weeks. Subjects returned to their baseline D(Ca) for the following two treatments, allowing for a 7-day washout period between each experimental HD. cPWP, carotido-radial (c-r) and carotido-femoral (c-f) pulse wave velocities (PWV), plasma level of ionized calcium (iCa) and intact parathyroid hormone (PTH) were measured prior to and immediately after each experimental HD session. Data were analysed by the general linear model for repeated measures and by the general linear mixed model.

RESULTS

Eighteen patients with a mean age of 48.9 +/- 18 years and a median duration of HD of 8.7 months (range 1-87 months) completed the study. In post-HD, iCa decreased with D(Ca) of 1.00 mmol/L (-0.14 +/- 0.04 mmol/L, P < 0.001), increased with a D(Ca) of 1.50 mmol/L (0.10 +/- 0.06 mmol/L, P < 0.001) but did not change with a D(Ca) of 1.25 mmol/L. Tests of within-subject contrast showed a linear relationship between higher D(Ca) and a higher post-HD Deltac-f PWV, Deltac-r PWV and Deltamean BP (P < 0.001, P = 0.008 and P = 0.002, respectively). Heart rate-adjusted central augmentation index (AIx) decreased significantly after HD, but was not related to D(Ca). The timing of wave refection (Tr) occurred earlier after dialysis resulting in a linear relationship between higher D(Ca) and post-HD earlier Tr (P < 0.044). In a multivariate linear-mixed model for repeated measures, the percentage increase in c-f PWV and c-r PWV was significantly associated with the increasing level of iCa, whereas the increasing level of DeltaMBP was not significant. In contrast, the percentage decrease in Tr (earlier wave reflection) was determined by higher DeltaMBP and higher ultrafiltration, whereas the relative change in AIx was inversely determined by the variation in the heart rate and directly by DeltaMBP.

CONCLUSION

We conclude that D(ca) and acute changes in the serum iCa concentration, even within physiological range, are associated with detectable changes of arterial stiffness and cPWP. Long-term studies are necessary to evaluate the long-term effects of D(Ca) modulation on arterial stiffness.

Stress, menopausal status and nocturnal blood pressure dipping patterns among hypertensive women

BACKGROUND

A less than 10% decline in blood pressure during the night is known as a nondipping blood pressure (BP) pattern. Nondipping BP has been shown to be associated with target organ damage and poorer cardiovascular outcomes. Additionally, some evidence suggests that hyper-tensive nondipping women are at greater risk for target organ damage than hypertensive nondipping men.

OBJECTIVE

To determine whether stress, demographics, menopausal status or sleep quality are associated with nondipping BP among hyperten-sive women.

METHODS

A cross-sectional study design was used to describe the rela-tionship between stress and dipping status among a sample of hypertensive women and to describe the sample by age, ethnicity, marital status, meno-pausal status, current medications and sleep quality.

RESULTS

The study sample consisted of 47 women (mean [+/- SD] age 57+/-13.9 years) with essential or office hypertension who underwent 24 h ambulatory BP monitoring, and completed stress and sleep quality measurements. Thirty-one women (66%) were classified as dippers and 16 (34%) were classified as nondippers. Nondippers were older (P=0.04), postmenopausal (P=0.003) and had lower stress scores (P=0.02) than their dipper counterparts. Postmenopausal status sig-nificantly predicted nondipping (OR 16; 95% CI 1.9 to 136.4).

CONCLUSION

These findings were of interest given that some women had a nondipping BP pattern and significantly lower stress scores. It is pos-sible that there are fundamentally different physiological mechanisms that explain this nondipping phenomenon. In the future, the identification of specific hemodynamic mechanisms associated with nondipping could potentially influence the choice of antihypertensive treatment regimens for nondipper hypertensive patients.

Blood pressure variability and prevalence of hypertension using automated readings from multiple visits to a pharmacy-based community-wide programme

Blood pressure (BP) measurements taken outside the routine office context may be a useful adjunct strategy to monitor BP. Community-based BP data can also provide estimates of the prevalence of elevated BP. We compared multiple readings taken on different days in pharmacies using an automated BpTRU device during a cardiovascular health programme targeting community-dwelling older adults. Mean systolic (S) and diastolic (D) BP values were compared over time using repeated measures analysis of variance for all participants with at least three separate sets of readings (n=317). BP variability was then examined among four subgroups based on report of antihypertensive medication or no treatment, and normal or elevated SBP at the initial visit (< or >or=140, or 130 if diabetes reported). Prevalence of elevated BP was compared across visits. Overall, mean SBP decreased between visits 1 and 2 (140.4 vs 137.1 mm Hg; P<0.001). Among participants with normal SBP at the initial visit, SBP did not vary significantly, whether or not antihypertensive treatment was reported. Those with initially elevated SBP experienced a significant decrease between visits 1 and 2, also regardless of treatment status. Prevalence of elevated BP decreased from visits 1 to 2 (55.8 vs 48.9%; P=0.026) and from visits 1 to 3 (55.8 vs 42.9%; P<0.001). Analyses of BP data from a community-based programme using an accurate device showed that initial readings may inflate the population estimate of elevated BP. Findings suggest that more than one set of BP readings measured on different occasions are needed, particularly if the first set is elevated.

Enhancing hypertension awareness and management in the elderly: lessons learned from the Airdrie Community Hypertension Awareness and Management Program (A-CHAMP)

BACKGROUND

High blood pressure (BP) is an established and modifiable cardiovascular risk factor; however, awareness and management of this primarily asymptomatic disease remains suboptimal.

OBJECTIVES

The Airdrie Community Hypertension Awareness and Management Program (A-CHAMP) was a community-based BP program for seniors designed to improve public and health care provider awareness and management of hypertension.

METHODS

Volunteer peer health educators (VPHEs) were recruited from the community and trained to manage BP screening sessions in local pharmacies. Airdrie (Alberta) residents 65 years of age and older were invited by their family physicians (FPs) to attend the A-CHAMP sessions. VPHEs identified participants' cardiovascular risk factors, assessed BP with a validated automated device and implemented a management algorithm. Participants with BP higher than 159/99 mmHg were directed to their pharmacists and FPs. All participants with elevated BP at the initial A-CHAMP session were invited to return to a follow-up session four to six months later.

RESULTS

Thirty VPHEs were recruited and trained. All 15 FPs and all six pharmacies in Airdrie participated. VPHEs assessed 406 seniors (approximately 40% of Airdrie seniors) during the three-month program. One hundred forty-eight participants (36.5%) had elevated BP at their first session. Of these, 71% returned for the follow-up session four to six months later. The mean (+/- SD) systolic BP decreased by 16.9+/-17.2 mmHg (P<0.05, n=105) compared with their first visit, and 56% of participants (59 of 105) reached Canadian targets for BP.

CONCLUSIONS

A-CHAMP raised awareness, and identified and managed seniors with hypertension. At follow-up, BP showed statistically and clinically significant and sustained improvement. Participating health care providers and VPHEs indicated that A-CHAMP was effective and feasible in improving awareness and control of hypertension.

Automated blood pressure measurement for diagnosing hypertension

Guidelines for the management of hypertension have started to include home blood pressure (BP) and 24-h ambulatory BP monitoring as preferred methods for diagnosing hypertension. The next step will be to incorporate automated office BP measurement into the algorithm for diagnosing hypertension. Recent studies support this approach with automated office BP readings being closely correlated with the ambulatory BP.

Ambulatory impedance cardiography in hypertension: a validation study

The management of hypertension is improved by knowledge of the hemodynamics underlying blood pressure. Impedance Cardiography (ICG) provides data on a range of hemodynamic variables that affect blood pressure. However, ICG captures only fixed descriptions of hemodynamic characteristics. Improvements in ambulatory technology have led to the development of the Ambulatory Impedance Monitor (AIM) which records hemodynamic data during the activities of daily living. The purpose of this study was to evaluate the sensitivity of the AIM to detect hemodynamic changes associated with postural shift in persons with hypertension. Using a repeated measures cross-over design, sitting and standing hemodynamic measures were taken in seventeen persons with hypertension while wearing the AIM-BpTRU system designed for standard office use and the AIM-Spacelabs system designed for ambulatory monitoring. Both AIM-blood pressure monitoring systems detected significant changes from sitting to standing posture in heart rate (p=0.03), stroke volume (p=0.002), left ventricular ejection time (p<0.001), systemic vascular resistance (p=0.03) and diastolic blood pressure (p<0.001). Additionally, both systems generated measures of cardiac function that were positively correlated (p<0.001) and not significantly different (p>0.05). Our findings support previous work and demonstrate that the AIM provides valid and reliable estimates of cardiac function in persons with hypertension.

Effect of sevelamer on aortic pulse wave velocity in patients on hemodialysis: a prospective observational study

Aortic stiffening and aortic calcification are risk factors for cardiovascular events in hemodialysis (HD) patients, and these 2 risk factors are interrelated. Sevelamer decreases aortic calcification but its effect on aortic stiffness has not been investigated previously. Thirteen HD patients commencing sevelamer treatment and 13 matched controls were followed for 11 months. Aortic pulse wave velocity (PWV), augmentation index (AIx), and levels of inhibitors of vascular calcification (fetuin-A, matrix-GLA-protein, osteoprotegerin/RANKL) were measured at baseline and at the end of follow-up, and the differences between the groups were compared. Determinants of the changes in PWV during follow-up were assessed by multivariate linear regression. At baseline, PWV was 9.93 (2.10) m/s in sevelamer-treated patients and 9.20 (2.84) m/s in control patients (p=0.464). By the end of follow-up, PWV decreased by 0.83 (2.3) m/s in sevelamer-treated patients while it increased by 0.93 (1.88) m/s in controls (p=0.042). The direction of changes in AIx were similar, but not statistically significant. There were no significant differences in the levels of inhibitors of calcification either at baseline or during follow-up. In multivariate linear regression sevelamer treatment, diabetes, heart rate, and C-reactive protein were related to the change in PWV. These data suggest that sevelamer treatment is associated with an improvement in aortic stiffness in HD patients, but it does not seem to affect serum levels of inhibitors of vascular calcification.

Automated Measurement of Blood Pressure in Routine Clinical Practice

In recent years, automated devices have been developed to record blood pressure (BP) accurately in the home and during usual daily activities. Clinical outcome studies have clearly shown home BP and 24-hour ambulatory BP to be significantly better predictors of future cardiovascular events compared with BP recorded in the office setting using mercury sphygmomanometry. It is also now possible to measure office BP with the patient resting quietly alone in the examining room using an automated device. Studies in routine clinical practice using this approach have demonstrated that automated office BP can eliminate most of the white coat effect seen with manual BP measurement. The automated office BP also correlates significantly better than does the routine office BP with the 24-hour ambulatory BP, the gold standard for predicting risk of future cardiovascular events. Sufficient evidence now exists to consider incorporating automated office BP into an algorithm for diagnosing hypertension.

A comparison of two sphygmomanometers that may replace the traditional mercury column in the healthcare workplace

OBJECTIVE

Alternatives to the traditional, but possibly toxic mercury sphygmomanometer are needed for accurate blood pressure measurements in the medical workplace. We compared the performance of two commercially available potential replacements for the mercury column; an anaeroid manometer (Baum & Co) and an automated oscillometric device (Omron HEM-907), using the mercury sphygmomanometer as a standard, in the same participants.

METHODS

Two independent observers performed simultaneous triplicate blood pressure readings for 512 participants. The average difference and standard deviation of the difference comparing the mercury column vs. the anaeroid and automated devices were calculated for each of the three paired systolic and diastolic blood pressure readings.

RESULTS

Both devices met the Association for the Advancement of Medical Instrumentation criteria for sphygmomanometers (<5 mmHg average difference, <8 mmHg standard deviation of the difference) for all three readings. Compared with the mercury standard, there were no significant differences (by paired t-test) with the anaeroid device (-0.83/0.73 mmHg, P=0.25/0.09), but the automated device slightly overestimated systolic blood pressure (by 2.12 mmHg, P=0.002) and underestimated diastolic blood pressure (by 2.36 mmHg, P=0.0002). The first reading was significantly higher and had a larger standard deviation than the second or third readings across all manometers.

CONCLUSIONS

The automated device performed as well as an anaeroid manometer operated by well trained, experienced observers. The two alternative devices to the mercury sphygmomanometer examined in this study may be potential replacement devices for blood pressure measurement.

"A heart for Vienna"--the prevention program for the big city. Blue-collar workers as a special target group

OBJECTIVES

To create awareness of cardiovascular health status by screening for cardiovascular risk factors, and thereby motivate people to improve their life style habits. This was carried out in form of a project within the framework of the government prevention programme "A Heart for Vienna" focussing on urban blue-collar workers, a population at greatest risk for developing cardiovascular disease.

RESULTS

The prevalence of hypertension, overweight, obesity, abdominal obesity and smoking were 29.7 %, 62.4 %, 16.4 %, 29.3 %, and 49.8 %, respectively. 87.6 % presented at least one of the screened cardiac risk factors. The prevalence of hypertension, overweight, obesity and abdominal obesity increased with age. Hypertension, overweight and abdominal obesity were significantly more prevalent among unskilled compared to skilled male bluecollar workers. The prevalence of obesity and abdominal obesity was more than 1.5 times higher among female compared to male blue-collar workers.

CONCLUSION

Blue-collar workers represent a population where health promotion and prevention of cardiovascular disease should have high priority. Within the bluecollar group itself the cardiovascular risk profile worsened with reduction in skill level.

[Factors related to the differences in blood pressure values assessed by auscultatory or oscillometric methods]

BACKGROUND AND OBJECTIVE

Measurement of blood pressure by using the auscultatory method coupled with mercury sphygmomanometer is rapidly being replaced for monitor using the oscillometric one. Discrepancies between the two methods and the factors related to them were analyzed in a large subset of adults.

MATERIAL AND METHOD

Blood pressure values were obtained sequentially in the same arm by using a mercury sphygmomanometer and a Spacelabs monitor devices. The relationship between both kinds of measurements was assessed by the Pearson's correlation coefficients and the concordance by using the Bland and Altman method. Differences between the two methods were calculated and the factors related to the differences were sought by multiple regression models.

RESULTS

A total of 1,742 adult subjects were analyzed. Pearson's correlation coefficients were 0.927, 0.922, 0.886, 0.962 for SBP, DBP, MBP and PR, respectively. Oscillometric method overestimate and infraestimate SBP values in the two extreme of SBP values, the lowest SBP the highest the values and vice versa. A similar trend was observed for DBP although the differences were minor. Pulse wave amplitude explains the 24% of the variance observed for SBP and arm circumference the 8% for DBP.

CONCLUSIONS

Blood pressure values measured by oscillometric methods are influenced for pulse wave amplitude and by the arm circumference. These need to be taken in account when blood pressure assessment is obtained by using this method.

Validation of two automatic devices for self-measurement of blood pressure according to the International Protocol of the European Society of Hypertension: the Omron M6 (HEM-7001-E) and the Omron R7 (HEM 637-IT)

BACKGROUND

Two electronic devices for self-measurement of blood pressure - a brachial monitor, the Omron M6, and a wrist monitor, the Omron R7 - were evaluated in two separate studies according to the International Protocol of the European Society of Hypertension.

DESIGN

The International Validation Protocol is divided into two phases: the first phase is performed on 15 selected participants (45 pairs of blood pressure measurements); if the device passes this phase, 18 supplementary participants are included (54 pairs of blood pressure measurements) making a total number of 33 participants (99 pairs of blood pressure measurements) on whom the final validation is performed.

METHODS

The same methodology recommended by the European Society of Hypertension protocol was applied for both studies. In each study and for each participant, four blood pressure measurements were taken simultaneously by two trained observers using mercury sphygmomanometers alternately with three measurements taken by the tested device. The difference between the blood pressure value given by the device and that obtained by the two observers (mean of the two observers) was calculated for each measure. The 99 pairs of blood pressure differences were classified into three categories (<or=5, <or=10 and <or=15 mmHg). The number of differences in each category was compared with the number required by the International Protocol. An individual analysis was then done to determine the number of comparisons <or=5 mmHg for each participant. At least 22 of the 33 participants should have two of their three comparisons <or=5 mmHg.

RESULTS

In both studies, the two tested devices passed the first and the second phases of the validation process. The average differences between the device and mercury sphygmomanometer readings were 0.8+/-2.7 and -1.9+/-3.3 mmHg for systolic and diastolic blood pressure, respectively, for the Omron M6 device, and 0.2+/-4.2 and 0.2+/-2.9 mmHg for systolic and diastolic blood pressure, respectively, for the Omron R7 device. For both devices, readings differing by less than 5, 10 and 15 mmHg for systolic and diastolic blood pressure values fulfill the recommendation criteria of the International Protocol as well as the individual analysis.

CONCLUSIONS

The Omron M6 (HEM-7001-E) and the Omron R7 (HEM 637-IT) devices fulfilled the validation recommendations of the International Protocol.

A community-based program for cardiovascular health awareness

OBJECTIVE

The objective of the Cardiovascular Health Awareness Program (CHAP) is to improve the processes of care related to the cardiovascular health of older adults.

PARTICIPANTS

Two Ontario communities including family physicians (FP), pharmacists, public health units and nurses, volunteer peer health educators, older adult patients and community organizations.

SETTING

Community pharmacies and family physician offices.

INTERVENTION

CHAP is designed to close a process of care loop around cardiovascular health awareness that originates from, and returns to, the FP. Older patients are invited by their FP to attend pharmacy CHAP sessions. At these sessions, trained volunteer peer health educators (PHEs) assist patients both in recording their blood pressure using a calibrated automated device and in completing a cardiovascular risk profile. This information is relayed to their respective FP via an automated computerized database. Pharmacists and patients receive copies of the results. Based on these cumulative risk profiles, patients are advised to follow-up with their FP.

OUTCOMES

Of the FPs and pharmacists asked, 47% and 79%, respectively, agreed to participate in the project. 39% of older adult patients invited by their FPs attended the CHAP community pharmacy sessions. Of these, 100% agreed to having their risk profile, including their blood pressure readings, forwarded to their FP. Positive feedback about CHAP was expressed by the volunteer PHEs, the FPs and the pharmacists.

CONCLUSION

The community-based pharmacy CHAP sessions are a feasible way of improving patient, physician, and pharmacist access to reliable blood pressure measurements and to cardiovascular health information. A randomized trial is in progress that will assess the impact of CHAP on monitoring of blood pressure.

Automated blood pressure measurement in routine clinical practice

OBJECTIVE

To compare blood pressure measurements taken in routine clinical practice using an automated recorder, the BpTRU (VSM MedTech Ltd, Coquitlam, Canada), with readings taken by a conventional mercury sphygmomanometer.

METHODS

Fifty consecutive patients [28 women, 22 men; mean (+/-SD) age 62+/-16 years] referred to a specialist for management of hypertension had blood pressure taken on the first visit in random order using both a mercury sphygmomanometer and an automated device.

RESULTS

The mean initial automated reading (mmHg) taken with the observer present (162+/-27/85+/-12) was similar to the mean manual blood pressure taken in duplicate (163+/-23/86+12). Both values were higher (P<0.001) than the mean of the next five readings taken with the automated recorder when the patient was resting quietly alone (142+/-21/80+/-12). Women exhibited a greater fall in blood pressure with the automated device than men.

CONCLUSIONS

Use of an automated blood pressure recorder can eliminate some of the white-coat effect associated with readings taken by a mercury sphygmomanometer.

Automated assessment of blood pressure using BpTRU compared with assessments by a trained technician and a clinic nurse

OBJECTIVE

To determine the accuracy and reproducibility of a new automated blood pressure manometer (BpTRU) relative to auscultatory blood pressure assessed by a research nurse and to that assessed by a clinic nurse.

METHODS

Firefighters in a cohort study had blood pressure assessed on up to five occasions with BpTRU and by a trained research technician. Patients in an internal medicine clinic had blood pressure assessed by the clinic nurse and by BpTRU. The absolute values of blood pressure, reproducibility and effect on hypertension classification were compared with the different methods.

RESULTS

The research technician readings were higher than the BpTRU readings at visit 1 (3.0/2.7 mmHg, P<0.0001) but the readings converged by visits 4-5 because of a greater reduction in the research nurse readings. The BpTRU readings had similar reproducibility and classification of hypertension as the research technician but did not exhibit terminal digit preference while the research technician readings did. The BpTRU had substantially lower readings (8/7 mmHg) and fewer hypertensive readings than those of the nurse in the internal medicine clinic.

CONCLUSIONS

This preliminary study found that the BpTRU had desirable characteristics that suggest that it would be a suitable replacement for auscultatory assessment of blood pressure in clinical practice. A large confirmatory study performed in a usual clinic setting is required.

Validation of two devices for self-measurement of brachial blood pressure according to the International Protocol of the European Society of Hypertension: the SEINEX SE-9400 and the Microlife BP 3AC1-1

BACKGROUND

Two electronic devices for self-measurement of blood pressure at the brachial artery -- the Seinex SE-9400 and the Microlife BP 3AC1-1 -- were evaluated in two separate studies according to the International Protocol of the European Society of Hypertension.

DESIGN

The international validation protocol is divided into two phases: the first phase is performed on 15 selected participants (45 blood pressure measurements); if the device passes this phase, 18 supplementary participants are included (54 blood pressure measurements) making a total number of 33 participants (99 blood pressure measurements) on whom the final validation is performed.

METHODS

The same methodology recommended by the European Society of Hypertension protocol was applied for both studies. In each study and for each participant, four blood pressure measurements were taken simultaneously by two trained observers using mercury sphygmomanometers alternately with three measurements by the tested device. The difference between the blood pressure value given by the device and that obtained by the two observers (mean of the two observers) was calculated for each measure. The 99 differences were classified into three categories (< or =5, < or =10, < or =15 mmHg). The number of differences in each category was compared with the number required by the ESH protocol. An individual analysis was then done to determine, for each participant, the number of comparisons < or =5 mmHg. At least 22 of the 33 participants should have two of their three comparisons < or =5 mmHg.

RESULTS

In both studies, the two tested devices passed the first phase of the validation process. For the complete analysis (phase 1 and phase 2), the average differences between the device and mercury sphygmomanometer readings were in the first study for the Seinex SE-9400 device 0.9+/-5.2 and -1.7+/-4.7 mmHg for systolic and diastolic blood pressure, respectively, and -0.2+/-4.5 and -2.0+/-4.8 mmHg for the Microlife BP 3AC1-1 device in the second study. For both devices, readings differing by less than 5, 10 and 15 mmHg for systolic and diastolic blood pressure values fulfill the recommendation criteria of the International Protocol as well as the individual analysis.

CONCLUSIONS

The Seinex SE-9400 and the Microlife BP 3AC1-1 devices fulfilled the validation recommendations of the International Protocol.