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

Ensuring accurate BP measurements

Accurate BP measurements are vital for determining appropriate medication and treatment regimens. This article describes a quality improvement project to increase compliance with the American Heart Association's guidelines for BP measurement.

A comparative study of automated blood pressure device and mercury-free LED blood pressure device using Lin's concordance correlation coefficient and other validity measures in Indian population

INTRODUCTION

Automated blood pressure (BP) monitor is widely used to assess the blood pressure (BP) of the study subjects in community-based researches. This study aims at the detection of hypertension by automated BP device and examines the concordance and validity between automated and mercury-free LED BP devices.

MATERIALS AND METHODS

This cross-sectional study was conducted in the tribal state of Jharkhand in India from January 2017 to June 2017. A total of 300 study participants aged more than 18 years were enrolled in this study. BP of the patients in the sitting position was measured three times each by automated device and mercury-free LED BP device. The different sets of readings were assessed by concordance correlation coefficient (CCC) and other validity measures.

RESULTS

The CCC for systolic and diastolic BP measured by automated and mercury-free LED BP is 0.88 and 0.85, respectively. The mean difference between systolic and diastolic BP by both the instruments is statistically insignificant (P > 0.05). The sensitivity, specificity, PPV, NPV, and accuracy of automated BP devices to predict hypertension is 96.61%, 92.21%, 75%, 99%, and 93%. The area under ROC for systolic and diastolic BP is 0.984 and 0.97, respectively with P values < 0.0001 in both the cases.

CONCLUSIONS

This study concluded that the overall automated BP machine has fair degree of agreement (CCC) with a manual BP device. The validity of this monitor to screen hypertension may also be considered in field settings.

Blood Pressure measurements are site dependent in a cohort of patients with neurological illness

Blood pressure (BP) management is a crucial part of critical care that directly affects morbidity and mortality. While BP has become a mainstay in patient care, the accuracy and precision of BP measures across commonly used sites (left upper arm, right upper arm, etc.) and methods have not been established. This study begins to fill this gap in literature by testing the null hypothesis that BP measurement does not vary according to site. This is a prospective, non-randomized, cross-sectional study of 80 neurocritical care unit patients. Near simultaneous non-invasive blood pressure (NIBP) readings from 4 different locations (bilateral upper arm, bilateral wrist) and, when available, intra-arterial blood pressure readings (IABP) were included. Pearson correlation coefficients and one-way repeated measures ANOVA were used to observe the systolic, diastolic, and mean arterial pressure (MAP) correlations. The BP measured at the four most common sites (left upper arm, left wrist, right upper arm, right wrist) had adequate correlation coefficients but were statistically significantly different and highly unpredictable. The median inter-site systolic variability was 10 mmHg (IQR 2 to 10 mmHg). The median inter-site MAP variability was 6mmHg with an interquartile range (IQR) of 3 to 9 mmHg. As expected, the values correlated to show that patients with high BP in one site tended to have high BP in another site. However, the unpredictable inter-site variability is concerning within the clinical setting where oftentimes BP measurement site is not standardized but resulting values are nevertheless used for treatment. There is prominent inter-site variability of BP measured across the 4 most common measurement sites. The variability persists across non-invasive (NIBP) and invasive (IABP) methods of assessment.

Comparison of cuff-based and cuffless continuous blood pressure measurements in children and adolescents

OBJECTIVE

In recent times, new methods of blood pressure measurements have been introduced, including cuffless blood pressure (BP) measurement device using pulse transit time (PTT) for calculation of BP values. However, it is still unknown how values obtained with a new cuffless device compare with standard ambulatory measurements in children. The main aim of the study was to investigate whether BP values measured by a cuffless PTT device are comparable with measurements by a standard upper arm cuff-based BP device.

METHODS

Thirty children were prospectively included. Blood pressure measurements using the cuffless device (Somnotouch-NIBP) and cuff-based standard device (Omron 907) were performed simultaneously on the left and right arm.

RESULTS

Mean systolic BP of the standard measurements was 123,47 ± 14,91 mmHg and 127,48 ± 15,98 mmHg (p < .001) measured by cuffless method. Mean diastolic BP of the standard ABPM measurements was 66,88 ± 11,86 mmHg and 68,52 ± 12,36 mmHg (p < .001). There were significant positive correlations between standard and cuffless measurements.

CONCLUSION

The results show that the created PWV-BP function produces a significant correlation between BP derived from the PWV and the SBP measured by sphygmomanometry. When applying this device in clinical practice, one may keep in mind that the reported mean values over 24 hours, awake and asleep time are not directly interchangeable with cuff-based standard 24-hour BP values. The measured BP values were higher by the new technique. Although differences in SBP between both methods reached values up to 20 mmHg, we think that the development of a cuffless BP monitoring system will provide novel solutions in various medical situations.

Automated Ambulatory Blood Pressure Measurements and Intraoperative Hypotension in Patients Having Noncardiac Surgery with General Anesthesia: A Prospective Observational Study

BACKGROUND

Normal blood pressure varies among individuals and over the circadian cycle. Preinduction blood pressure may not be representative of a patient's normal blood pressure profile and cannot give an indication of a patient's usual range of blood pressures. This study therefore aimed to determine the relationship between ambulatory mean arterial pressure and preinduction, postinduction, and intraoperative mean arterial pressures.

METHODS

Ambulatory (automated oscillometric measurements at 30-min intervals) and preinduction, postinduction, and intraoperative mean arterial pressures (1-min intervals) were prospectively measured and compared in 370 American Society of Anesthesiology physical status classification I or II patients aged 40 to 65 yr having elective noncardiac surgery with general anesthesia.

RESULTS

There was only a weak correlation between the first preinduction and mean daytime mean arterial pressure (r = 0.429, P < 0.001). The difference between the first preinduction and mean daytime mean arterial pressure varied considerably among individuals. In about two thirds of the patients, the lowest postinduction and intraoperative mean arterial pressures were lower than the lowest nighttime mean arterial pressure. The difference between the lowest nighttime mean arterial pressure and a mean arterial pressure of 65 mmHg varied considerably among individuals. The lowest nighttime mean arterial pressure was higher than 65 mmHg in 263 patients (71%).

CONCLUSIONS

Preinduction mean arterial pressure cannot be used as a surrogate for the normal daytime mean arterial pressure. The lowest postinduction and intraoperative mean arterial pressures are lower than the lowest nighttime mean arterial pressure in most patients.

Telemonitoring and remote counseling in hypertensive patients. Looking for new ways to do old jobs

XXI century emphasized humanity to embrace the digital era after a reality of Third and Fourth Industrial Revolutions, nowadays dictating new terms of social networking. It is expected that information and communication technologies integrated with value-based medicine will significantly impact healthcare delivery to tremendous number of patients with socially important noncommunicable diseases. Cardiovascular illnesses comprise the greatest part of such pathologies. Hypertension (HTN) being the most prevalent cardiovascular disease is also the key modifiable cardiovascular risk factor yet seems to be an attractive target for both value-based concept and telehealth interventions. Present review addresses up-to-date science on telehealth, sets out the main well-known, but yet unsolved challenges in management of HTN along with the new approaches involving telemedicine programs, digital health outlooks. The main barriers of telehealth implementation are also considered along with the possible solutions.

Automated office blood pressure measurements obtained with and without preceding rest are associated with awake ambulatory blood pressure

Automated office blood pressure (AOBP) measurement, attended or unattended, eliminates the white coat effect (WCE) showing a strong association with awake ambulatory blood pressure (ABP). This study examined the difference in AOBP readings, with and without 5 minutes of rest prior to three readings recorded at 1-min intervals. Cross-sectional data from 100 randomized selected hypertensives, 61 men and 39 women, with a mean age of 52.2 ± 10.8 years, 82% treated, were analyzed. The mean systolic AOBP values without preceding rest were 127.0 ± 18.2 mm Hg, and the mean systolic AOBP values with 5 minutes of preceding rest were 125.7 ± 17.9 mm Hg (P = .05). A significant order effect was observed for the mean systolic BP values when AOBP without 5 minutes of preceding rest was performed as the first measurement (130.0 ± 17.7 vs 126.5 ± 16.2, P = .008). When we used a target systolic AOBP ≥ 130 mm Hg, awake ABP yielded lower readings, while at a target systolic AOBP value of < 130 mm Hg higher awake ABP values were obtained. Our findings indicate that systolic AOBP can be initially checked without any preceding rest and if readings are normal can be accepted. Otherwise, when AOBP is ≥ 130 mm Hg, measurements should be rechecked with 5 minutes of rest.

Hypertension in Cancer Patients and Survivors: Epidemiology, Diagnosis, and Management

Cancer patients and survivors of cancer have a greater burden of cardiovascular disease compared to the general population. Much of the elevated cardiovascular risk in these individuals is likely attributable to hypertension, as individuals with cancer have a particularly high incidence of hypertension following cancer diagnosis. Treatment with chemotherapy is an independent risk factor for hypertension due to direct effects of many agents on endothelial function, sympathetic activity, and renin-angiotensin system activity as well as nephrotoxicity. Diagnosis and management of hypertension in cancer patients requires accurate blood pressure measurement and consideration of potential confounding factors, such as adjuvant treatments and acute pain, that can temporarily elevate blood pressure readings. Home blood pressure monitoring can be a useful tool to facilitate longitudinal blood pressure monitoring for titration of antihypertensive medications. Selection of antihypertensive agents in cancer patients should account for treatment-specific morbidities and target organ injury.

Going Beyond the Guidelines in Individualising the Use of Antihypertensive Drugs in Older Patients

Hypertension is commonly diagnosed in older patients, with increasing cardiovascular (CV) risk as systolic blood pressure (BP) increases. Maximising CV risk reduction must be reconciled with minimising the risk of treatment-related harms and burden, especially among frail, multi-morbid and older old patients who have been excluded from most randomised trials. Contemporary clinical guidelines, based on such trials, differ in their recommendations as to threshold levels warranting treatment with antihypertensive drugs (AHDs) and target levels that should be achieved. In optimising AHD prescribing in older patients, we propose the following decision framework: decide therapeutic goals in accordance with patient characteristics and preferences; estimate absolute CV risk; measure and profile BP accurately in ways that account for lability in BP levels and minimise error in BP measurement; determine threshold and target BP levels likely to confer net benefit, taking into account age, co-morbidities, frailty and cognitive function; and consider situations that warrant AHD deprescribing on the basis of potential current or future harm. In applying this framework to older persons, and based on a review of relevant randomised trials and observational studies, individuals most likely to benefit from treating systolic BP to no less than 130 mmHg are those of any age who are fit and have high baseline systolic BP (≥ 160 mmHg); high CV risk, i.e. established CV disease or risk of CV events exceeding 20% at 10 years; previous stroke or transient ischaemic attack; heart failure; and stage 3-4 chronic kidney disease with proteinuria. Individuals most likely to be harmed from treating BP to target systolic < 140 mmHg are those who have no CV disease and aged over 80 years; moderate to severe frailty, cognitive impairment or functional limitations; labile BP and/or history of orthostatic hypotension, syncope and falls; or life expectancy < 12 months. Treatment should never be so intense as to reduce diastolic BP to < 60 mmHg in any older person. At a time when guidelines are calling for less conservative management of hypertension in all age groups, we contend that a more temperate approach, such as that offered here and based on the totality of available evidence, may assist in maximising net benefit in older patients.

Calibration of blood pressure measurements in the Jackson Heart Study

BACKGROUND

In longitudinal research studies with follow-up examinations, the devices used to measure phenotypes may change over time. When a device change occurs, the two devices should be calibrated to each other to ensure that measurements are comparable. This paper details the Jackson Heart Study (JHS) blood pressure (BP) comparability study.

PARTICIPANTS AND METHODS

During its second clinic exam (2005-2008), the JHS switched from a random-zero sphygmomanometer (RZS) BP measurement device to an oscillometric device (OD). During this exam, BP measurements from both an RZS and an OD were taken simultaneously in 2117 participants for the purpose of calibration. Five methods for calibrating systolic BP (SBP) and diastolic BP (DBP) were considered: ignoring the change, ordinary least squares regression, adding the average difference, Deming regression, and robust regression.

RESULTS

Using the RZS and OD, the mean (SD) SBP was 125.5 (19.2) and 126.5 (19.9), respectively, and the mean (SD) DBP was 76.4 (10.6) and 74.0 (11.0), respectively. The correlation between RZS and the OD was 0.90 for SBP and 0.80 for DBP. The prevalence of high BP and hypertension and associations with albuminuria were similar when applying each of the five calibration methods. Robust regression was chosen for calibration, giving the following equations:(Equation is included in full-text article.)These equations had a higher R statistic than using calibration equations from the Coronary Artery Risk Development in Young Adults Study and the Heinz Nixdorf Recall Study.

CONCLUSIONS

The JHS BP data have been calibrated using the above equations for use in future analyses.

Screening for hypertension: an elevated office blood pressure measurement is valuable, adding an automated one is even better

BACKGROUND

Previous studies have examined the relevance of hypertension (HTN) screening in walk-in clinics. So far, no valid algorithm has been proposed on how to integrate HTN screening in this context. The aim of our study was to assess, in a walk-in clinic setting, the HTN screening strategy for performing an automated office blood pressure (AOBP) measurement following an initially high office blood pressure (OBP) measurement.

PATIENTS AND METHODS

Included participants were adults with nonemergent medical conditions and an initial walk-in clinic OBP between systolic 140 and/or diastolic 90 mmHg and systolic 180 and/or diastolic 110 mmHg. AOBP was performed with patients unattended. The 24-h ambulatory blood pressure measurement (ABPM) was used as the diagnostic threshold.

RESULTS

Fifty participants were included in the study. The overall HTN prevalence as confirmed by the 24-h ABPM was 46% [95% confidence interval (CI): 32.19-59.81]. After an elevated OBP, AOBP over diagnostic thresholds occurred in 32 patients and were confirmed by ABPM in 20 participants, leading to a 62.5% positive predictive value (95% CI: 51.5-72.3%). Measurements under the AOBP diagnostic threshold occurred in 18 patients and were confirmed by ABPM in 15 participants, leading to a negative predictive value of 83.3% (95% CI: 62.3-93.8%).

CONCLUSION

In a walk-in clinic, an elevated OBP is a useful screening tool due its ability to recognize nearly one in two patients as actually hypertensive. Adding an AOBP makes it possible to specify what course of action to take. This ultimately results in better targeting of patients for an ABPM referral.

Ankle pulse pressure to diastole ratio as a novel non-invasive costless screening tool for subclinical atherosclerosis

Atherosclerosis develops gradually as a subclinical condition and eventually becomes clinically apparent as heart disease or stroke. The degree of decreased arterial compliance affects both pulse pressure (PP) and diastolic blood pressure (DBP). These relations would be clear in the distal periphery. We propose that the ankle PP/ankle DBP ratio (APPD) can uncover the ongoing subclinical vascular risk. Based on the elastic chamber theory, APPD = (Cs-Cd)/(Cd-C0) in which Cs, Cd, and C0 represent arterial compliance at systolic pressure, diastolic pressure, and zero-pressure. For a given ventricular ejection, the value of Cs-Cd (i.e. PP) positively differs in the same person from brachium to ankle based on the distance from the heart, degree of arterial stiffness, and the local arterial function. On the other hand, the decreased arterial compliance increases the speed of reflected pulse waves to the heart resulting in earlier ventricular ejection by which the value of Cd-C0 (i.e. DBP) decreases over the arterial tree. In the same person, studies of ankle-brachial blood pressure (BP) differences revealed that PP greatly differed from brachium to ankle while DBPs were of minimal change or almost equivalent. However, DBP would be lower in those with arterial stiffness compared to others of the same age. Accordingly, APPD increases as arterial compliance decreases. Moreover, decreased APPD after a certain limit would reflect either local arterial stenosis or a compromised left ventricular function. When we divided ankle PP by ankle DBP, we could control the diversity of ankle PP as being not related to the BP level and possibly fluctuates in the same person. Additionally, APPD will indicate the extra rapid reflected pulse wave given in decreased DBP. Since increased common carotid artery intima-media thickness (CIMT) is a well-established marker of atherosclerosis, we initially studied 115 subjects apparently free form vascular diseases and had not taken a drug that can affect BP on the day of the study, aged 40-60 years, without a history of stroke, coronary heart disease or peripheral vascular disease to evaluate the relation between APPD and CIMT. The association was statistically significant even after adjusting for age, sex and important covariates and the area under the receiver operating characteristic curve was 0.902 ± 0.031. Therefore, the potential applicability of APPD as a tool for subclinical atherosclerosis was greatly proven.

Conditional prescriptions of oral antihypertensive drugs for the management of hypertension urgencies in the inpatient setting: An observational study

WHAT IS KNOWN AND OBJECTIVES

The management of hypertension urgencies during hospitalization may generally not necessitate urgent care. However, physicians frequently prescribe 'as needed' antihypertensive drugs for which administration is triggered by blood pressure thresholds. The lack of rationale for this hospital practice led us to study oral conditional antihypertensive (OCA) prescriptions. We aimed to estimate the prevalence of OCA prescriptions and to establish their characteristics.

METHODS

In our institution, prescriptions are computerized. The study was retrospectively performed using a hospital clinical data warehouse over a 5-year period.

RESULTS AND DISCUSSION

The prevalence of OCA prescriptions was 6.9% among subjects treated with an antihypertensive drug. The median duration of these prescriptions was 4 days, until the day of the patient discharge in 78.8% stays. The calcium channel inhibitors were the main (79.9%) pharmacological class prescribed, with mostly prescriptions of nicardipine. OCA prescriptions were associated with another antihypertensive medication in 58.8% of the prescriptions; for 19.3%, it was a medication belonging to the same pharmacological class than the OCA drug prescribed. Regarding the computerized drafting, 39.6% of the conditional prescriptions were considered uninterpretable. At least one administration by nurses concerned 65.1% of the OCA prescriptions. The mean SBP and DBP before the initiation of an OCA drug was 142.9 ± 28.2 and 75.8 ± 24.5 mm Hg, respectively, relative to 143.0 ± 24.9 and 77.6 ± 19.9 mm Hg after the initiation (P = .8 for SBP and P = .06 for DBP).

WHAT IS NEW AND CONCLUSION

The originality of this study lies in the use of a clinical data warehouse to evaluate OCA prescriptions in hospital. These prescriptions are current, often uninterpretable and mostly ordered until patient discharge. Such drug orders could be associated with an increased risk of iatrogenic events and/or administration errors. This underlies the need for developing decision support tools and computerized protocols to manage hypertension urgencies.

Effects of Acute Consumption of Noni and Chokeberry Juices vs. Energy Drinks on Blood Pressure, Heart Rate, and Blood Glucose in Young Adults

The purpose of this study has been to determine the effect of acute consumption of noni and chokeberry juices vs. energy drinks on blood pressure, heart rate, and blood glucose. The subjects divided into 4 groups, which consumed three portions of noni or chokeberry juices (30 mL or 200 mL, respectively) and energy drink (ED) or water (200 mL) at one-hour intervals. All participants had their blood pressure (BP), both systolic and diastolic BP (SBP and DBP), as well as heart rate (HR) and blood glucose (BG), measured. Consumption of noni juice caused a significant decrease in SBP and DBP of 5.0% and 7.5%, respectively, while, the consumption of chokeberry juice slightly decreased only DBP by 3.6%. On the contrary, consumption of three portions of EDs caused a significant increase in DBP by 14.7%. The BG of participants consuming noni juice decreased by 7.3%, while the consumption of EDs increased BG by as much as 15.8%. Acute consumption of noni juice contributed to a significantly decreased SBP, DBP, and HR as well as a mild reduction of BG. Consumption of chokeberry juice caused only a slight reduction of DBP. Contrary to juices, EDs consumption resulted in an increase of blood pressure (especially DBP) and blood glucose. The results of the study showed that noni juice may be effective in lowering blood pressure and blood sugar levels, but there is a need to continue research on the long-term effect of this juice.

Detecting and managing hypertensive disorders in pregnancy: a cross-sectional analysis of the quality of antenatal care in Nigeria

BACKGROUND

Nigeria has one of the highest rates of maternal mortality in the world (576/100,000 births), with a significant proportion of death attributed to hypertensive disorders in pregnancy (HDPs). High quality antenatal care (ANC) plays a crucial role in early detection and management of HDPs. We conducted an assessment of quality of antenatal care, and its capacity to detect and manage HDPs, in two tiers of Nigerian facilities, with the aim of describing the state of service delivery and identifying the most urgent gaps.

METHODS

Quality of antenatal care was assessed and compared between primary healthcare centers (PHCs) (n = 56) and hospitals (secondary + tertiary facilities, n = 39) in seven states of Nigeria. A cross-sectional design captured quality of care using facility inventory checklists, semi-structured interviews with healthcare providers and clients, and observations of ANC consultations. A quality of care framework and scoring system was established based on aspects of structure, process, and outcome. Average scores were compared using independent sample t-tests and measures of effect were assessed by multivariate linear regression.

RESULTS

All domains of quality except provider interpersonal skills scored below 55%. The lowest overall scores were observed in provider knowledge (49.9%) and provider technical skill (47.7%). PHCs performed significantly worse than hospitals in all elements of quality except for provider interpersonal skills. Provider knowledge was significantly associated with their level of designation (i.e., obstetrician vs. other providers).

CONCLUSIONS

In order to provide high quality care, ANC in Nigeria must experience massive improvements to inventory, infrastructure and provider knowledge and training. In particular, ANC programs in PHCs must be revitalized to minimize the disparity in quality of care provided between PHCs and hospitals. The relatively low quality of care observed may be contributing to Nigeria's high rate of maternal mortality and burden of disease attributed to HDPs.

Fed and fasted states on heart rate variability, hemodynamic heart rate and blood pressure in adults submitted to moderate aerobic exercise

Background

Heart rate variability (HRV) has proven to be a powerful non-invasive tool to investigate cardiac autonomic control and, seems to be influenced by nutritional status and exercise practice. However, the acute effects of fed or fasting states on HRV and blood pressure (BP) during low-to-moderate intensity aerobic exercise are currently unknown. Therefore, we investigated the baseline values and behavior of HRV, BP, and heart rate (HR) before and after low-to-moderate intensity aerobic exercise in fed and fasted states in healthy adults.

Methods

12 healthy individuals with mean age (SD) 59.0 (9.1) years performed two tests on a treadmill at 80% of the mean velocity of the 6-min walking test separated by 48 h: 12 h fasted (FST) or 1 h fed (FED). HRV, BP and HR were analyzed at rest, posttest, and at the third, fifth, and seventh minutes of recovery.

Results

HRV and HR presented no significant alterations between nutritional conditions. HR at baseline was not different between nutritional conditions. Diastolic blood pressure was increased during the fasted baseline state.

Conclusions

The results of the current study provide that 12 h overnight fasting does not seem to be enough to affect significant changes in the autonomic modulation in healthy adults submitted to low-to-moderate intensity aerobic exercise.

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.

Automated Office-Based Blood Pressure Measurement: an Overview and Guidance for Implementation in Primary Care

PURPOSE OF REVIEW

The purposes of this study are to review evidence supporting the use of automated office blood pressure (AOBP) measurement and to provide practical guidance for implementing it in clinical settings.

RECENT FINDINGS

Mean AOBP readings correlate with awake ambulatory blood pressure monitor (ABPM) values and predict cardiovascular outcomes better than conventional techniques. However, heterogeneity among readings suggests that AOBP does not replace ABPM. Blood pressure (BP) measurement protocols differ among commonly described AOBP devices, but all produce valid BP estimates. Rest periods should not precede AOBP with BpTRU devices but should occur before use with Omron HEM-907 and Microlife WatchBP Office devices. Attended and unattended AOBP appear to produce similar results. This review also describes a framework to aid AOBP's implementation in clinical practice. Evidence supports AOBP as the preferred method for measuring BP in office settings, but this approach should be a complement to out-of-office measurements, such as self-measured BP monitoring or 24-h ABPM, not a substitute for it.

Assessment of Blood Pressure: Techniques and Implications From Clinical Trials

Hypertension is a global health problem and without adequate diagnosis and treatment is a risk factor for morbidity and mortality. Proper assessment of blood pressure is key to diagnosis and management of hypertension. Different methods of measurement are available for use and varying techniques are applied to patient care. Understanding the proper methods of blood pressure measurement both in and out of the physician's office is crucial for providing appropriate care to an individual patient. In addition, understanding the techniques used in research, on which current guidelines are based, is critical for proper application to daily practice. In this article, we review the types of blood pressure measurement techniques, discuss the benefits and limitations to each, explore future technological advances in measurement devices, and provide insight into research techniques, which ultimately guide our practice.

Frequency of Tongue Cleaning Impacts the Human Tongue Microbiome Composition and Enterosalivary Circulation of Nitrate

The oral microbiome has the potential to provide an important symbiotic function in human blood pressure physiology by contributing to the generation of nitric oxide (NO), an essential cardiovascular signaling molecule. NO is produced by the human body via conversion of arginine to NO by endogenous nitric oxide synthase (eNOS) but eNOS activity varies by subject. Oral microbial communities are proposed to supplement host NO production by reducing dietary nitrate to nitrite via bacterial nitrate reductases. Unreduced dietary nitrate is delivered to the oral cavity in saliva, a physiological process termed the enterosalivary circulation of nitrate. Previous studies demonstrated that disruption of enterosalivary circulation via use of oral antiseptics resulted in increases in systolic blood pressure. These previous studies did not include detailed information on the oral health of enrolled subjects. Using 16S rRNA gene sequencing and analysis, we determined whether introduction of chlorhexidine antiseptic mouthwash for 1 week was associated with changes in tongue bacterial communities and resting systolic blood pressure in healthy normotensive individuals with documented oral hygiene behaviors and free of oral disease. Tongue cleaning frequency was a predictor of chlorhexidine-induced changes in systolic blood pressure and tongue microbiome composition. Twice-daily chlorhexidine usage was associated with a significant increase in systolic blood pressure after 1 week of use and recovery from use resulted in an enrichment in nitrate-reducing bacteria on the tongue. Individuals with relatively high levels of bacterial nitrite reductases had lower resting systolic blood pressure. These results further support the concept of a symbiotic oral microbiome contributing to human health via the enterosalivary nitrate-nitrite-NO pathway. These data suggest that management of the tongue microbiome by regular cleaning together with adequate dietary intake of nitrate provide an opportunity for the improvement of resting systolic blood pressure.

Blood Pressure Assessment in Adults in Clinical Practice and Clinic-Based Research: JACC Scientific Expert Panel

The accurate measurement of blood pressure (BP) is essential for the diagnosis and management of hypertension. Restricted use of mercury devices, increased use of oscillometric devices, discrepancies between clinic and out-of-clinic BP, and concerns about measurement error with manual BP measurement techniques have resulted in uncertainty for clinicians and researchers. The National Heart, Lung, and Blood Institute of the U.S. National Institutes of Health convened a working group of clinicians and researchers in October 2017 to review data on BP assessment among adults in clinical practice and clinic-based research. In this report, the authors review the topics discussed during a 2-day meeting including the current state of knowledge on BP assessment in clinical practice and clinic-based research, knowledge gaps pertaining to current BP assessment methods, research and clinical needs to improve BP assessment, and the strengths and limitations of using BP obtained in clinical practice for research and quality improvement activities.

Clinical Implementation of Self-Measured Blood Pressure Monitoring, 2015-2016

INTRODUCTION

Self-measured blood pressure monitoring (SMBP) plus additional clinical support is an evidence-based strategy that improves blood pressure control. Despite national recommendations for SMBP use and potential cost savings, insurance coverage for implementation is limited in the U.S. and little is known regarding clinical implementation.

METHODS

In 2017, using 2015 and 2016 DocStyles survey data from 1,590 primary care physicians and nurse practitioners in U.S. outpatient facilities, SMBP-related clinical practices and provider roles were assessed.

RESULTS

Almost all (97%) respondents reported using SMBP. Among 1,539 who used SMBP, more than half (60%) used SMBP for a combination of diagnostic and treatment purposes, whereas 24% used SMBP for diagnosis only and 16% used SMBP for treatment only. The most common methods for patients to share SMBP results with clinical staff were paper log (68%); during appointments (66%); by telephone (37%); by secure website (22%); or by secure e-mail (19%). Nearly all (98%) respondents reported that medication adjustments were provided to patients based on SMBP readings. About 15% did not counsel patients regarding cuff size, and 8% did not validate patient devices. Only 13% of respondents reported having monitor loaner programs, and availability did not vary by the financial status of the patient population (p=0.59).

CONCLUSIONS

SMBP is used widely in outpatient facilities as reported in the survey, although provider roles and SMBP-related practices vary, and gaps exist regarding patient counseling, device validation, and loaner program availability. As part of efforts to improve hypertension control, healthcare professionals can promote increased use of best practices for SMBP, whereas insurers can implement standardization and support of SMBP.

Blood Pressure Control and Other Quality of Care Metrics for Patients with Obesity and Diabetes: A Population-Based Cohort Study

INTRODUCTION

There are no population-level estimates in the United States for achievement of blood pressure goals in patients with diabetes and hypertension by obesity weight class.

AIM

We sought to examine the relationship between the extent of obesity and the achievement of guideline-recommended blood pressure goals and other quality of care metrics among patients with diabetes.

METHODS

We conducted an observational population-based cohort study of electronic health data of three large health systems from 2010-2012 in rural, urban and suburban settings of 51,229 adults with diabetes. Outcomes were achievement of diabetes quality of care metrics: blood pressure, A1c, and LDL control, and A1c and LDL testing. Two blood pressure goals were examined given the recommendation for adults with diabetes of 130/80 mmHg from JNC7 and the recommendation of 140/90 mmHg from JNC8 in 2014.

RESULTS

Patients in obesity classes I, II, and III with diagnosed hypertension were less likely to achieve blood pressure control at both the 140/90 mmHg and 130/80 mmHg control levels. The patients from obesity class III had the lowest likelihood of achieving control at the 130/80 mmHg goal, and control was markedly worse for the 130/80 mmHg threshold in all weight classes. There were minimal to no differences by weight class in LDL and A1c control and LDL and A1c testing.

CONCLUSIONS

Although the cardiovascular risk for patients with obesity and diabetes is greater than for non-obese patients with diabetes, we found that patients with obesity are even further behind in achieving blood pressure control.

Comparison of automated clinical and research blood pressure measurements: Implications for clinical practice and trial design

Discrepancies between clinic and research blood pressure (BP) measurements lead to uncertainties in translating hypertension management guidelines into practice. We assessed the concordance between standardized automated clinic BP, from a primary care clinic, and research BP, from a randomized trial conducted at the same site. Mean single-visit clinic BP was higher by 4.4/3.8 mm Hg (P = 0.007/<0.001). Concordance in systolic BP (SBP) improved with closer proximity of measurements (difference = 2.5 mm Hg, P = 0.21 for visits within 7 days), but not averaging across multiple visits (difference =5.1(9.2) mm Hg; P < 0.001). This discrepancy was greater among female participants. Clinic-based difference in SBP between two visits was more variable than research-based change (SD = 19.6 vs 14.0; P = 0.002); a 2-arm trial using clinic measurements would need 95% more participants to achieve comparable power. Implementation of a bundled standardization intervention decreased discrepancies between clinic and research BP, compared to prior reports. However, clinic measurements remained higher and more variable, suggesting treatment to research-based targets may lead to overtreatment and using clinic BP approximately halves power in trials.

A Primer on the New Guideline for the Prevention, Detection, Evaluation, and Management of Hypertension

Hypertension is a leading risk factor for the development of cardiovascular disease. In 2017, the American College of Cardiology and the American Heart Association published a new guideline for the prevention, detection, evaluation, and management of hypertension. The guideline adjusts the clinical parameters for diagnosis and management of hypertension. In this article we summarize the updates and provide some background on these changes as they relate to nursing practice implications, with specific implications for women's health.

Prospective external validation of the Predicting Out-of-OFfice Blood Pressure (PROOF-BP) strategy for triaging ambulatory monitoring in the diagnosis and management of hypertension: observational cohort study

OBJECTIVE

To prospectively validate the Predicting Out-of-OFfice Blood Pressure (PROOF-BP) algorithm to triage patients with suspected high blood pressure for ambulatory blood pressure monitoring (ABPM) in routine clinical practice.

DESIGN

Prospective observational cohort study.

SETTING

10 primary care practices and one hospital in the UK.

PARTICIPANTS

887 consecutive patients aged 18 years or more referred for ABPM in routine clinical practice. All underwent ABPM and had the PROOF-BP applied.

MAIN OUTCOME MEASURES

The main outcome was the proportion of participants whose hypertensive status was correctly classified using the triaging strategy compared with the reference standard of daytime ABPM. Secondary outcomes were the sensitivity, specificity, and area under the receiver operator characteristic curve (AUROC) for detecting hypertension.

RESULTS

The mean age of participants was 52.8 (16.2) years. The triaging strategy correctly classified hypertensive status in 801 of the 887 participants (90%, 95% confidence interval 88% to 92%) and had a sensitivity of 97% (95% confidence interval 96% to 98%) and specificity of 76% (95% confidence interval 71% to 81%) for hypertension. The AUROC was 0.86 (95% confidence interval 0.84 to 0.89). Use of triaging, rather than uniform referral for ABPM in routine practice, would have resulted in 435 patients (49%, 46% to 52%) being referred for ABPM and the remainder managed on the basis of their clinic measurements. Of these, 69 (8%, 6% to 10%) would have received treatment deemed unnecessary had they received ABPM.

CONCLUSIONS

In a population of patients referred for ABPM, this new triaging approach accurately classified hypertensive status for most, with half the utilisation of ABPM compared with usual care. This triaging strategy can therefore be recommended for diagnosis or management of hypertension in patients where ABPM is being considered, particularly in settings with limited resources.

A Network Meta-Analysis Comparing Semaglutide Once-Weekly with Other GLP-1 Receptor Agonists in Japanese Patients with Type 2 Diabetes

INTRODUCTION

Semaglutide once-weekly (QW) is a novel glucagon-like peptide-1 (GLP-1) analogue administered at a 0.5 or 1.0 mg dose. In the absence of head-to-head trials between semaglutide QW and other GLP-1 receptor agonists (GLP-1 RAs) in a Japanese population, a network meta-analysis (NMA) was performed. The objective was to assess the relative efficacy and safety of semaglutide QW vs GLP-1 RAs in Japanese patients with type 2 diabetes (T2DM), with a specific focus on the comparison between semaglutide 0.5 mg QW and dulaglutide 0.75 mg QW.

METHODS

A systematic review (SR) and supplementary Japanese searches were conducted to identify trials of GLP-1 RAs in Japanese patients on diet and exercise, who have previously received 0-1 oral antidiabetic drugs (OADs). Data at 52-56 weeks were extracted for the following outcomes (feasible for analysis in an NMA): glycated hemoglobin (HbA_1c), fasting plasma glucose (FPG), weight, systolic blood pressure (SBP), and overall hypoglycemia. The data were synthesized using an NMA and a Bayesian framework.

RESULTS

Four trials, identified from the SR and Japanese-specific searches, were relevant for inclusion in the NMA. When compared to dulaglutide 0.75 mg QW, semaglutide 0.5 mg QW was shown to provide significant reductions in HbA_1c [- 0.61% (12.3 mmol/mol)], weight (- 1.45 kg), SBP (- 5.03 mmHg), and FPG (- 1.26 mmol/L). No significant differences in the proportion of patients achieving a HbA_1c level < 7% (53 mmol/mol) or the risk of overall hypoglycemia were observed between semaglutide 0.5 mg QW and dulaglutide 0.75 mg QW.

CONCLUSION

Overall, semaglutide 0.5 mg QW was associated with significant reductions from baseline in HbA_1c, weight, SBP, and FPG compared with dulaglutide 0.75 mg QW in Japanese patients with T2DM. These data may provide valuable evidence for clinical decision-making, cost-effectiveness analyses, and health technology appraisal (HTA) requirements.

FUNDING

Novo Nordisk Pharma Ltd.

The role of clinic blood pressure for the diagnosis of hypertension

PURPOSE OF REVIEW

Recent data from randomized clinical trials and updates to hypertension guidelines warrant a review of the literature for the diagnosis and management of hypertension in the clinic setting. Although there have been significant advances in ambulatory blood pressure (BP) monitoring and home BP monitoring, office BP (OBP) measurements remains the primary means of diagnosis and treatment.

RECENT FINDINGS

The current review focuses on updated guidelines, proper technique, device selection, and the recent controversy regarding unattended BP measurements. We review the data on cardiovascular outcomes, the comparison of OBP with ambulatory BP monitoring and home BP monitoring and some of the pitfalls of OBP measurements.

SUMMARY

The current review highlights the need for constant review of BP goals to minimize cardiovascular risk and some of the ongoing controversies regarding OBP measurements.

Diagnostic precision of mentally estimated home blood pressure means

CONTEXT

Paper home blood pressure (HBP) charts are commonly brought to physicians at office visits. The precision and accuracy of mental calculations of blood pressure (BP) means are not known.

METHODS

A total of 109 hypertensive patients were instructed to measure and record their HBP for 1 week and to bring their paper charts to their office visit. Study section 1: HBP means were calculated electronically and compared to corresponding in-office BP estimates made by physicians. Study section 2: 100 randomly ordered HBP charts were re-examined repetitively by 11 evaluators. Each evaluator estimated BP means four times in 5, 15, 30, and 60 s (random order) allocated for the task. BP means and diagnostic performance (determination of therapeutic systolic and diastolic BP goals attained or not) were compared between physician estimates and electronically calculated results.

RESULTS

Overall, electronically and mentally calculated BP means were not different. Individual analysis showed that 83% of in-office physician estimates were within a 5-mmHg systolic BP range. There was diagnostic disagreement in 15% of cases. Performance improved consistently when the time allocated for BP estimation was increased from 5 to 15 s and from 15 to 30 s, but not when it exceeded 30 s.

CONCLUSION

Mentally calculating HBP means from paper charts can cause a number of diagnostic errors. Chart evaluation exceeding 30 s does not significantly improve accuracy. BP-measuring devices with modern analytical capacities could be useful to physicians.

Could self-measured office blood pressure be a hypertension screening tool for limited-resources settings?

Blood pressure (BP) was assessed by patients themselves in recently published trials. Self-measured office blood pressure (SMOBP) seems particularly interesting for limited health resources regions. The aim of our study was to evaluate the relationship between SMOBP values and those estimated by ambulatory blood pressure monitoring (ABPM). Six hundred seventy-seven patients were evaluated using both, SMOBP and ABPM. The differences between SMOBP and daytime ABPM were evaluated with paired "t" test. The correlations among SMOBP and ABPM were estimated using Pearson's r. The accuracy of SMOBP to identify abnormal ABPM was determined using area under ROC curve (AUC). Sensitivity, specificity, and positive and negative predictive values were calculated for different SMOBP cut-points. Using the average of three readings, systolic SMOBP was higher (3.7 (14.2) mmHg, p < 0.001) and diastolic SMOBP lower (1.5 (8.1) mmHg, p < 0.001) than ABPM. Both BP estimates had a significant correlation, r = 0.67 and r = 0.75 (p < 0.01) for systolic and diastolic BP, respectively. Systolic SMOBP predicted systolic abnormal ABPM; the AUC were 0.80 (0.77-0.84) and 0.78 (0.74-0.81) for daytime and 24 h hypertension, respectively. Diastolic SMOBP predicted diastolic hypertension, AUC 0.86 (0.83-0.88) for both daytime and 24 h hypertension. Neither correlations nor AUCs improved significantly using the average of five readings. SMOBP ≥ 160/90 mmHg was highly specific (>95%) to identify individuals with hypertension in the ABPM; SMOBP < 130/80 mmHg reasonably discarded abnormal ABPM. In conclusion, a high proportion of individuals could be classified adequately using SMOBP, reducing the necessity of healthcare resources and supporting its utility for screening purposes.

The Effect of Acute Consumption of Energy Drinks on Blood Pressure, Heart Rate and Blood Glucose in the Group of Young Adults

Background: Energy drinks (EDs) are very popular among young people, who consume them for various reasons. A standard ED typically contains 80 mg of caffeine, as well as glucose, taurine, vitamins and other ingredients. Excessive consumption of EDs and accumulation of the above ingredients, as well as their mutual interactions, can be hazardous to the health of young adults. The purpose of this study was to assess the effect of acute consumption of energy drinks on blood pressure, heart rate and blood glucose. Methods: The study involved 68 volunteers, healthy young adults (mean age 25 years), who were divided into two groups: the first consumed three EDs at one-hour intervals, and the second drank the same amount of water. All participants had their blood pressure (BP)—systolic and diastolic (SBP and DBP)—as well as heart rate (HR) and blood glucose (BG) measured. In addition, participants could report any health problems before and after consuming each portion of ED. Results: In the above experiment, having consumed three portions of ED (240 mg of caffeine), the participants presented a significant increase in DBP (p = 0.003), by over 8%, which coincided with a lack of any significant impact on SBP (p = 0.809). No significant changes were noted in HR (p = 0.750). Consumption of EDs caused a significant increase (p < 0.001) in BG, by ca. 21%, on average. Some participants reported various discomforts, which escalated after 2 and 3 EDs. Conclusions: Acute consumption of EDs contributed to increased diastolic blood pressure, blood glucose and level of discomfort in healthy young people. Our results reinforce the need for further studies on a larger population to provide sufficient evidence.

Hypertension Canada's 2018 Guidelines for Diagnosis, Risk Assessment, Prevention, and Treatment of Hypertension in Adults and Children

Hypertension Canada provides annually updated, evidence-based guidelines for the diagnosis, assessment, prevention, and treatment of hypertension in adults and children. This year, the adult and pediatric guidelines are combined in one document. The new 2018 pregnancy-specific hypertension guidelines are published separately. For 2018, 5 new guidelines are introduced, and 1 existing guideline on the blood pressure thresholds and targets in the setting of thrombolysis for acute ischemic stroke is revised. The use of validated wrist devices for the estimation of blood pressure in individuals with large arm circumference is now included. Guidance is provided for the follow-up measurements of blood pressure, with the use of standardized methods and electronic (oscillometric) upper arm devices in individuals with hypertension, and either ambulatory blood pressure monitoring or home blood pressure monitoring in individuals with white coat effect. We specify that all individuals with hypertension should have an assessment of global cardiovascular risk to promote health behaviours that lower blood pressure. Finally, an angiotensin receptor-neprilysin inhibitor combination should be used in place of either an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker in individuals with heart failure (with ejection fraction < 40%) who are symptomatic despite appropriate doses of guideline-directed heart failure therapies. The specific evidence and rationale underlying each of these guidelines are discussed.

The impact of unrecorded readings on the precision and diagnostic performance of home blood pressure monitoring: a statistical study

Hypertension is a major cardiovascular risk factor. To address the disease adequately, most clinicians rely on home blood pressure monitoring (HBPM). However, the impact of unrecorded BP values on the precision and diagnostic performance of BP schedules is unknown. We obtained 103 HBP patients schedules from a previous study. Then, readings were randomly removed from each schedule in order to create new incomplete schedules using a resampling technique. We obtained 10,000 new incomplete schedules. For each number of randomly removed readings, the percentages of incomplete schedules outside a systolic/diastolic blood pressure (SBP/DBP) range of 5/3 mmHg were calculated from the same complete patient's schedule. The sensitivity and specificity of incomplete HBPM schedules regarding BP control were also assessed. One hundred three HBPM schedules were analyzed. Mean patients' age was 67.9 ± 9.9 years. In non-diabetic patients, the mean BP of complete schedules' means was 131.9 ± 12.4/75.5 ± 10.5. In diabetic patients, the mean BP of complete schedules' means was 135.5 ± 14.0/73.4 ± 8.2 mmHg. When schedules were composed of 14 and 21 random measures, differences over 5 mmHg were seen in 2.6% and 0.1% of non-diabetic patients' schedule and 3.7% and 0.1% of diabetic patients' schedule, respectively. At 21 measurements, sensitivity and specificity were approximately 95% and 98% in non-diabetic patients and 90% and 99% in non-diabetic patients, respectively. HBPM precision and diagnostic performance improve rapidly with accumulation of readings. Incomplete schedules composed of 21 readings can provide an almost perfect diagnostic tool compared with the complete schedule reference.

Are self-reported telemonitored blood pressure readings affected by end-digit preference: a prospective cohort study in Scotland

OBJECTIVE

Simple forms of blood pressure (BP) telemonitoring require patients to text readings to central servers creating an opportunity for both entry error and manipulation. We wished to determine if there was an apparent preference for particular end digits and entries which were just below target BPs which might suggest evidence of data manipulation.

DESIGN

Prospective cohort study SETTING: 37 socioeconomically diverse primary care practices from South East Scotland.

PARTICIPANTS

Patients were recruited with hypertension to a telemonitoring service in which patients submitted home BP readings by manually transcribing the measurements into text messages for transmission ('patient-texted system'). These readings were compared with those from primary care patients with uncontrolled hypertension using a system in which readings were automatically transmitted, eliminating the possibility of manipulation of values ('automatic-transmission system').

METHODS

A generalised estimating equations method was used to compare BP readings between the patient-texted and automatic-transmission systems, while taking into account clustering of readings within patients.

RESULTS

A total of 44 150 BP readings were analysed on 1068 patients using the patient-texted system compared with 20 705 readings on 199 patients using the automatic-transmission system. Compared with the automatic-transmission data, the patient-texted data showed a significantly higher proportion of occurrences of both systolic and diastolic BP having a zero end digit (OR 2.1, 95% CI 1.7 to 2.6) although incidence was <2% of readings. Similarly, there was a preference for systolic 134 and diastolic 84 (the threshold for alerts was 135/85) (134 systolic BP OR 1.5, 95% CI 1.3 to 1.8; 84 diastolic BP OR 1.5, 95% CI 1.3 to 1.9).

CONCLUSION

End-digit preference for zero numbers and specific-value preference for readings just below the alert threshold exist among patients in self-reporting their BP using telemonitoring. However, the proportion of readings affected is small and unlikely to be clinically important.

TRIAL REGISTRATION NUMBER

ISRCTN72614272; Post-results.

A bundled quality improvement program to standardize clinical blood pressure measurement in primary care

We evaluated use of a program to improve blood pressure measurement at 6 primary care clinics over a 6-month period. The program consisted of automated devices, clinical training, and support for systems change. Unannounced audits and electronic medical records provided evaluation data. Clinics used devices in 81.0% of encounters and used them as intended in 71.6% of encounters, but implementation fidelity varied. Intervention site systolic and diastolic blood pressure with terminal digit "0" decreased from 32.1% and 33.7% to 11.1% and 11.3%, respectively. Improvement occurred uniformly, regardless of sites' adherence to the measurement protocol. Providers rechecked blood pressure measurements less often post-intervention (from 23.5% to 8.1% of visits overall). Providers at sites with high protocol adherence were less likely to recheck measurements than those at low adherence sites. Comparison sites exhibited no change in terminal digit preference or repeat measurements. This study demonstrates that clinics can apply a pragmatic intervention to improve blood pressure measurement. Additional refinement may improve implementation fidelity.

Cardiovascular risk profiles in a lupus cohort: what do different calculators tell us?

Background

Cardiovascular disease (CVD) is the leading cause of death worldwide and this risk is increased in patients with SLE who may not conform to traditional cardiovascular risk profiles.

Aims

To determine the prevalence of high CVD risk among patients with SLE calculated using different risk calculators, and to characterise those identified as high risk.

Methods

A cross-sectional analysis to estimate CVD risk using the Framingham Risk Equation (Framingham score) and an SLE-specific CVD risk equation (SLE score) was undertaken using data from a single centre cohort. The characteristics of patients identified as 'high risk' by the SLE score only (the 'missed group') were compared with those identified by the Framingham score (the 'conventional group').

Results

146 patients were included; 22 (15%) and 44 (30%) were determined to be at 'high risk' based on the Framingham and SLE scores, respectively. Patients in the 'missed group' were less likely to have traditional risk factors and were more likely to be female (81% vs 50%; p=0.03), younger (mean age 54 vs 69 years p<0.01) and have lower systolic blood pressure (132 vs 143 mm Hg; p=0.05). Of those deemed high risk, only a minority were treated to target blood pressure and lipid levels.

Conclusions

A large proportion of patients with SLE could be re-classified as high risk using a formula that incorporates SLE disease-related parameters. These patients have different profiles to those identified using a conventional risk model. Optimal CVD risk assessment and management warrants further attention in SLE.

The effects of awareness and count duration on adult respiratory rate measurements: An experimental study

AIMS AND OBJECTIVES

To investigate whether awareness of manual respiratory rate monitoring affects respiratory rate in adults, and whether count duration influences respiratory rate estimates.

BACKGROUND

Nursing textbooks typically suggest that the patient should ideally be unaware of respiratory rate observations; however, there is little published evidence of the effect of awareness on respiratory rate, and none specific to manual measurement. In addition, recommendations about the length of the respiratory rate count vary from text to text, and the relevant empirical evidence is scant, inconsistent and subject to substantial methodological limitations.

DESIGN

Experimental study with awareness of respiration monitoring (aware, unaware; randomised between-subjects) and count duration (60 s, 30 s, 15 s; within-subjects) as the independent variables. Respiratory rate (breaths/minute) was the dependent variable.

METHODS

Eighty-two adult volunteers were randomly assigned to aware and unaware conditions. In the baseline block, no live monitoring occurred. In the subsequent experimental block, the researcher informed aware participants that their respiratory rate would be counted, and did so. Respirations were captured throughout via video recording, and counted by blind raters viewing 60-, 30- and 15-s extracts. The data were collected in 2015.

RESULTS

There was no baseline difference between the groups. During the experimental block, the respiratory rates of participants in the aware condition were an average of 2.13 breaths/minute lower compared to unaware participants. Reducing the count duration from 1 min to 15 s caused respiratory rate to be underestimated by an average of 2.19 breaths/minute (and 0.95 breaths/minute for 30-s counts). The awareness effect did not depend on count duration.

CONCLUSIONS

Awareness of monitoring appears to reduce respiratory rate, and shorter monitoring durations yield systematically lower respiratory rate estimates.

RELEVANCE TO CLINICAL PRACTICE

When interpreting and acting upon respiratory rate data, clinicians should consider the potential influence of these factors, including cumulative effects.