Difference between clinic and daytime blood pressure is not a measure of the white coat effect

[Effet blouse blanche résiduel : un outil pertinent en soins premiers?]

BACKGROUND

White coat effect (WCE) and white coat hypertension (WCH) are hardly both compared in primary care.

OBJECTIVE

To assess the usefulness of repeated measures of systolic blood pressure (SBP) to dissociate various forms of white-coat interactions.

METHODS

An open cross-sectional study on consecutive patients treated or not for high blood pressure was made in family physicians' offices. SBP was measured 5 times by an electronic device. Measurements were performed before (SBP1) and after (SBP5) the office visit by a lay assistant and at the beginning (SBP2), middle (SBP3) and end (SBP4) of visit, by the family physician. Home BP (HBPM) was measured from 3 consecutive days by the patient. WCE and office WCE tail (OWCET) were defined, respectively, as a 10 mmHg SBP increase or decrease between SBP2-SBP1 or SBP4-SBP2. WCH was considered when HBPM was normal (SBP < 135 mmHg) at home and high during the SBP2 office visit.

RESULTS

Two hundred five patients (134 women versus 71 men, ratio 1.9, aged 59.8±15.7 years) were recruited. In categorical terms, there were 51 patients (25%) who presented with WCE, OWCET was seen in 121 patients (62%) and 47 patients (23%) had WCH. Only 36 patients (18%) presented both OWCET and WCE and 32 (16%) had both OWCET and WCH. The receiver operating characteristic curves (ROCs) of OWCET in diagnosing WCE or WCH were respectively 0.67 (p<0.0001) and 0.53 (NS).

CONCLUSION

Thus, OWCET was predictive of WCE and not of WCH and it is worthwhile to be measured in the family physician office.

“What if It’s not Just an Item of Clothing?” – A Narrative Review and Synthesis of the White Coat in the Context of Aged Care

Although increasingly disputed, the white coat uniform is ubiquitous in geriatric care, which may reflect a phenomenon called medicalisation of ageing. This narrative review is the first attempt at integrating several theoretical approaches, such as the “white coat effect” and “enclothed cognition”, in order to gain a comprehensive understanding of the use of this clothing item. Based on extensive empirical evidence, we will examine the consequences of wearing a uniform, not only on patients (in this case, older patients) and healthcare professionals, but also on their relationship. The white coat has powerful symbolic functions for healthcare professionals and is still preferred by older adults. However, the negative repercussions of wearing a uniform require us to question its use, particularly in environments where older persons live, such as nursing homes.

Hypertension, white-coat hypertension and masked hypertension in Australia: findings from the Australian Diabetes, Obesity, and Lifestyle Study 3

BACKGROUND AND METHOD

The Australian Diabetes, Obesity, and Lifestyle Study is a national, population-based examination of ∼11 000 adults with a third follow-up phase at 12 years. The aim was to use ambulatory blood pressure monitoring (ABPM) in a subsample (n = 508) of the main Australian Diabetes third follow-up cohort to determine the proportion with established, masked or white-coat hypertension in city and regional centers and the effectiveness of diagnosis and treatment.

RESULTS

Mean age was 58.9 years, BMI was 27.6 kg/m with 53% women. The mean clinic BP was 127/73 mmHg and mean 24-h BP was 121/73 mmHg. Using regression analysis estimations, the predicted ABPM daytime equivalent for the hypertension threshold values of 140/90 mmHg were 136/90 mmHg. There were 43% classified as hypertensive due to either ABPM 24-h more than 130/80 mmHg (17%) or taking antihypertensive therapy (25%). Ambulatory SBP/DBP were higher in men (24-h + 6.4/4.9 mmHg, P < 0.001) compared with women. There was only 3% with white-coat but 21% with masked hypertension indicating 24% misdiagnosis. Based on ABPM, 9% were treated and still hypertensive, which was three times more common in men (14%) than women (4%). Thus 36% had not reached target. There were no differences between urban and rural participants. Based on ABPM, nearly half the participants were hypertensive while only a quarter were taking antihypertensive therapy.

CONCLUSION

The findings highlight the importance of out-of-office BP assessments and the considerable gaps in effectively diagnosing and treating hypertension.

Ambulatory blood pressure monitoring over 24 h: A Latin American Society of Hypertension position paper-accessibility, clinical use and cost effectiveness of ABPM in Latin America in year 2020

Accurate office blood pressure measurement remains crucial in the diagnosis and management of hypertension worldwide, including Latin America (LA). Office blood pressure (OBP) measurement is still the leading technique in LA for screening and diagnosis of hypertension, monitoring of treatment, and long-term follow-up. Despite this, due to the increasing awareness of the limitations affecting OBP and to the accumulating evidence on the importance of ambulatory BP monitoring (ABPM), as a complement of OBP in the clinical approach to the hypertensive patient, a progressively greater attention has been paid worldwide to the information on daytime and nighttime BP patterns offered by 24-h ABPM in the diagnostic, prognostic, and therapeutic management of hypertension. In LA countries, most of the Scientific Societies of Hypertension and/or Cardiology have issued guidelines for hypertension care, and most of them include a special section on ABPM. Also, full guidelines on ABPM are available. However, despite the available evidence on the advantages of ABPM for the diagnosis and management of hypertension in LA, availability of ABPM is often restricted to cities with large population, and access to this technology by lower-income patients is sometimes limited by its excessive cost. The authors hope that this document might stimulate health authorities in each LA Country, as well as in other countries in the world, to regulate ABPM access and to widen the range of patients able to access the benefits of this technique.

Evaluation of the applicability of deep breathing test in the diagnosis of hypertension with white-coat effect in Chinese patients in primary care

Purpose

The current gold standard for the diagnosis of white-coat effect is by the 24-h ambulatory blood pressure monitoring (ABPM) which may not be readily available in every primary care setting. Previous studies had shown that deep breathing, through modulating the baroreceptor reflex sensitivity to vagal stimulation over 30 to 60 s, was useful in detection of the white-coat effect. The aim of our study was to evaluate the diagnostic accuracy of the deep breathing test (DBT) as compared with the gold standard of ABPM in the diagnosis of hypertension with white-coat effect in Chinese patients in primary care.

Methods

This cross sectional study recruited 178 consecutive, eligible, consented, hypertensive patients receiving treatment at a local public primary care Hypertension Clinic.

The diagnostic accuracy of the DBT in all recruited patients, patients not taking beta-adrenergic blockers and patients with different clinic SBP cut-off before the DBT by means of area under the receiver operating characteristic (ROC) curve, sensitivity, specificity, positive and negative predictive values was evaluated.

Results

The results for the ROC curves for systolic and diastolic BP changes after the DBT were statistically insignificant. The ROC curve was statistically significant for SBP change in patients not taking beta-adrenergic blockers and with pre-DBT clinic SBP ≥ 165 mmHg (ROC curve area of 0.719, 95% CI 0.53 to 0.91, p = 0.04). The corresponding sensitivity and specificity of the DBT were 40.9 and 90.9% respectively if SBP drop was > 30 mmHg.

Conclusion

The DBT, even though could not be clinically applied to all patients, was proven to be a potential screening and diagnostic test for white-coat effect in Chinese hypertensive patients with a pre-test SBP of ≥165 mmHg and who were not taking beta-adrenergic blockers.

Trial registration

This study was approved by Kowloon East Cluster/ Kowloon Central Cluster Research Ethics Committee/Institutional Review Board of Hospital Authority of Hong Kong under the registration KC/KE-16-0084/ER-3.

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

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

Automated Versus Manual Blood Pressure Measurement: A Randomized Crossover Trial in the Emergency Department of a Tertiary Care Hospital in Karachi, Pakistan: Are Third World Countries Ready for the Change?

BACKGROUND

Hypertension has proven to be a strong liability with 13.5% of all mortality worldwide being attributed to elevated blood pressures in 2001. An accurate blood pressure measurement lies at the crux of an appropriate diagnosis. Despite the mercury sphygmomanometer being the gold standard, the ongoing deliberation as to whether mercury sphygmomanometers should be replaced with the automated oscillometric devices stems from the risk mercury poses to the environment.

AIM

This study was performed to check the validity of automated oscillometric blood pressure measurements as compared to the manual blood pressure measurements in Karachi, Pakistan.

MATERIAL AND METHODS

Blood pressure was recorded in 200 individuals aged 15 and above using both, an automated oscillometric blood pressure device (Dinamap Procare 100) and a manual mercury sphygmomanometer concomitantly. Two nurses were assigned to each patient and the device, arm for taking the reading and nurses were randomly determined. SPSS version 20 was used for analysis. Mean and standard deviation of the systolic and diastolic measurements from each modality were compared to each other and P values of 0.05 or less were considered to be significant. Validation criteria of British Hypertension Society (BHS) and the US Association for the Advancement of Medical Instrumentation (AAMI) were used.

RESULTS

Two hundred patients were included. The mean of the difference of systolic was 8.54 ± 9.38 while the mean of the difference of diastolic was 4.21 ± 7.88. Patients were further divided into three groups of different systolic blood pressure <= 120, > 120 to = 150 and > 150, their means were 6.27 ± 8.39 (p-value 0.175), 8.91 ± 8.96 (p-value 0.004) and 10.98 ± 10.49 (p-value 0.001) respectively. In our study 89 patients were previously diagnosed with hypertension; their difference of mean systolic was 9.43 ± 9.89 (p-value 0.000) and difference of mean diastolic was 4.26 ± 7.35 (p-value 0.000).

CONCLUSIONS

Systolic readings from a previously validated device are not reliable when used in the ER and they show a higher degree of incongruency and inaccuracy when they are used outside validation settings. Also, readings from the right arm tend to be more precise.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Epidemiological Characteristics of Hypertension in the Elderly in Beijing, China

Background/Objectives

The prevalence rate of hypertension increases significantly with the aging society, and hypertension is obviously becoming a major health care concern in China. The aim of the study was to explore the epidemiological characteristics of hypertension in the elderly and to provide a basis for the prevention of hypertension.

Design

3-cross sectional studies in 2000, 2004, and 2007, respectively.

Setting

Beijing, China.

Participants

A group of 2,832, 1,828, and 2,277 elderly residents aged ≥60 years were included this study in 2000, 2004, and 2007, respectively.

Intervention

None.

Measurements

Statistical sampling techniques included cluster, stratification, and random selection. Trained staff used a comprehensive geriatric assessment questionnaire and a standard survey instrument to complete the assessments. During the person-to-person interviews, the participants’ demographic characteristics, living conditions, and health status were collected, and their blood pressure was measured.

Results

The prevalence rates (69.2%, 61.9%, and 56.0%) of hypertension and the control rates (22.6%, 16.7%, and 21.5%) lowered annually, while the awareness rates (43.7%, 55.8%, and 57.6%) of the treatment elevated annually in 2000, 2004, and 2007, respectively. There was no increase in the control rates for males (26.2%, 16.7%, and 20.8%), younger participants (28.0%, 18.4%, and 21.0%), and rural residents (19.5%, 9.6%, and 13.4%) in 2000, 2004, and 2007, respectively.

Conclusions

Our study findings indicated that the prevalence of hypertension is high in rural elderly participants, while the rates of awareness, treatment, and control were low. This suggests that effective public measures need to be developed to improve the prevention and control of hypertension.

European Society of Hypertension position paper on ambulatory blood pressure monitoring

Ambulatory blood pressure monitoring (ABPM) is being used increasingly in both clinical practice and hypertension research. Although there are many guidelines that emphasize the indications for ABPM, there is no comprehensive guideline dealing with all aspects of the technique. It was agreed at a consensus meeting on ABPM in Milan in 2011 that the 34 attendees should prepare a comprehensive position paper on the scientific evidence for ABPM.This position paper considers the historical background, the advantages and limitations of ABPM, the threshold levels for practice, and the cost-effectiveness of the technique. It examines the need for selecting an appropriate device, the accuracy of devices, the additional information and indices that ABPM devices may provide, and the software requirements.At a practical level, the paper details the requirements for using ABPM in clinical practice, editing considerations, the number of measurements required, and the circumstances, such as obesity and arrhythmias, when particular care needs to be taken when using ABPM.The clinical indications for ABPM, among which white-coat phenomena, masked hypertension, and nocturnal hypertension appear to be prominent, are outlined in detail along with special considerations that apply in certain clinical circumstances, such as childhood, the elderly and pregnancy, and in cardiovascular illness, examples being stroke and chronic renal disease, and the place of home measurement of blood pressure in relation to ABPM is appraised.The role of ABPM in research circumstances, such as pharmacological trials and in the prediction of outcome in epidemiological studies is examined and finally the implementation of ABPM in practice is considered in relation to the issue of reimbursement in different countries, the provision of the technique by primary care practices, hospital clinics and pharmacies, and the growing role of registries of ABPM in many countries.

Isolated increases in in-office pressure account for a significant proportion of nurse-derived blood pressure-target organ relations

AIMS

We determined the extent to which relationships between nurse-derived blood pressures (BPs) and cardiovascular damage may be attributed to isolated increases in in-office SBP independent of ambulatory BP.

METHODS

In 750 participants from a community sample, nurse-derived office BP, ambulatory BP, carotid-femoral pulse wave velocity (PWV; applanation tonometry and SphygmoCor software; n=662), and left ventricular mass indexed to height (LVMI; echocardiography; n=463) were determined.

RESULTS

Nurse-derived office BP was associated with organ changes independent of 24-h BP (LVMI; partial r=0.15, P<0.005, PWV; partial r=0.21, P<0.0001) and day BP. However, in both unadjusted (P<0.0001 for both) and multivariate adjusted models (including adjustments for 24-h BP; LVMI; partial r=0.14, P<0.01, PWV; partial r=0.21, P<0.0001), nurse office-day SBP (an index of isolated increases in in-office BP) was associated with target organ changes independent of ambulatory BP and additional confounders, with the highest quartile (≥15 mmHg) showing the most marked increases in LVMI (P<0.0005) and PWV (P<0.0001) as compared to the lowest quartile (<-5 mmHg). These relationships were reproduced in those with normotensive day BP values and the quantitative effect of nurse office-day BP on target organ changes was at least equivalent to that of ambulatory BP.

CONCLUSION

Nurse-elicited isolated increases in in-office BP account for a significant proportion of the relationship between nurse-derived BP and target organ changes independent of ambulatory BP. Therefore, high quality nurse-derived BP measurements do not approximate the impact of BP effects per se on cardiovascular damage.

Ambulatory blood pressure monitoring and prognosis in the management of essential hypertension

Over the past decade, several prospective outcome studies have demonstrated that ambulatory blood pressure measurements provide a better prediction of major cardiovascular events compared with clinic blood pressure measurements. This review summarizes the advantages of ambulatory blood pressure over clinic blood pressure to predict outcome in untreated and treated hypertensive subjects. Based on available evidence, an operational flow-chart in order to interpret results of ambulatory blood pressure for a better management of these subjects is suggested.

Does home blood pressure allow for a better assessment of the white-coat effect than ambulatory blood pressure?

BACKGROUND

The difference between clinic and ambulatory blood pressure (BP) is a poor estimate of the true white-coat effect (WCE) measured with beat-to-beat recording.

METHOD

We investigated whether the difference between clinic and home BP (home WCE) was a better estimate of true WCE than ambulatory WCE. In 73 young hypertensives, ambulatory WCE was calculated as the difference between clinic BP and the mean of two 24-h BP recordings, and home WCE as the difference between clinic and home BP (HBP) measured over 6 months. All individuals underwent beat-to-beat BP monitoring with the Finometer. During the recording, a white-coat test (true WCE) and a public speaking test were performed.

RESULTS

Ambulatory WCE correlated with home WCE (P  <  0.001 for systolic and diastolic BPs). However, both surrogate WCEs were unrelated to true WCE (P  =  0.93/0.36 and P  =  0.11/0.36, respectively). True WCE correlated with the BP reaction to public speaking (P  <  0.001/P  <  0.001), whereas both surrogate WCEs were unrelated to the BP response to this test (all P  >  0.21). Individuals were divided into two groups according to whether BP response to the doctor's visit was above (WCH+) or below (WCH-) the median. WCH+ patients had similar clinic and ambulatory BPs to WCH- but showed a higher BP response to public speaking.

CONCLUSION

As previously observed for ambulatory WCE, home WCE does not reflect the true BP reaction to doctor's visit. BP response to psychosocial stressors is increased in individuals with hyperreactivity to doctor's measurement but not in individuals with white-coat hypertension identified with either ambulatory or HBP measurement.

Diagnosis and management of patients with white-coat and masked hypertension

White-coat hypertension is characterized by an elevation in clinic blood pressure but normal home or ambulatory blood-pressure values, whereas patients with masked hypertension have normal clinic blood pressure and elevated ambulatory or home blood-pressure load. Both white-coat and masked hypertension are frequent clinical entities that need appropriate recognition and a close diagnostic follow-up. White-coat and masked hypertension seem to be associated with organ damage and increased cardiovascular risk, although not invariably. In addition, patients with masked or white-coat hypertension have an increased risk of abnormalities affecting their glucose and lipid profiles. Therefore, the diagnosis of these conditions should be accurate and include the assessment of cardiovascular as well as of metabolic risk. Once diagnosed, first-line therapeutic interventions should be nonpharmacological and aim at lifestyle changes, but drug treatment can be indicated, particularly when the patient's cardiovascular risk profile is elevated or when target-organ damage is detected.

Magnitude of the white-coat effect in the community pharmacy setting: the MEPAFAR study

BACKGROUND

There is little information regarding the community pharmacy blood pressure (CPBP) measurement method and their differences with home (HBP) or ambulatory BP (ABP). The aim of this study was to measure such differences and their variation over successive visits.

METHOD

Cross-sectional study carried out in eight pharmacies in Gran Canaria (Spain). The study included 169 treated hypertensive patients. BP was measured at the pharmacy (four visits), at HBP (4 days) and 24-h ABP monitoring. We defined pharmacy white-coat effect (PWCE) as differences between CPBP and HBP (home PWCE) or daytime ABP (ambulatory PWCE).

RESULTS

The overall (pooled values for all visits) ambulatory PWCE was not significantly different from zero for systolic BP (SBP) (-0.4 mm Hg (95% confidence interval (CI): -1.8 to 1.1)), but greater than zero for diastolic BP (DBP) (3.4 mm Hg (95% CI: 2.3 to 4.6)). The overall home PWCE was not significantly different from zero, both for SBP (1.2 mm Hg (95% CI: -0.1 to 2.6)) and DBP (0.1 mm Hg (95% CI: -0.7 to 1.0)). The ambulatory and home PWCE on the first visit were greater than zero (P < 0.001) (SBP/DBP): 3.5/4.8 and 1.9/1.5 mm Hg, respectively; but showed important reductions at the second visit and became not significantly different from zero, except the ambulatory PWCE in DBP, which persisted until the last visit.

CONCLUSION

The trend in the PWCE decreased over the successive visits to the pharmacy. Only the ambulatory PWCE in DBP proved to be statistically greater than zero after the second visit. Repeated CPBP measurements could be a useful alternative to assess the response to antihypertensive treatment.

The role of blood pressure variability in misdiagnosed clinic hypertension

Blood pressure (BP) assessment may be vulnerable to bias by increased BP variability. Uncertainty in determining BP control is inherent to the clinic setting. We analyzed a registry of 3949 patients referred for ambulatory BP monitoring. The difference between clinic and ambulatory readings was plotted against ambulatory BP variability, assessed by standard deviation. In addition, BP variability of patients with clinic and awake ambulatory hypertension was compared with that of patients with controlled BP and sustained hypertension, respectively. The average clinic-ambulatory systolic BP difference was 5 ± 17/3 ± 9 mm  Hg. Patients with >10-mm  Hg systolic difference had higher systolic ambulatory BP standard deviation (14.9 ± 4.2 mm  Hg) compared to patients with a difference of 0 to 10-mm  Hg (standard deviation 12.5 ± 3.7 mm  Hg). Patients with masking (negative clinic-ambulatory BP difference) also had comparatively higher standard deviation (14.4 ± 4.9 mm  Hg P<0.0001). Greater ambulatory BP variability carried increased risk for both false diagnosis of hypertension (odds ratio (OR): 2.09, 95% confidence interval (CI): 1.58-2.76), and missed clinic diagnosis of hypertension (OR: 1.86, 95% confidence interval: 1.48-2.33). The former was more striking in women, in whom high variability carried greater odds for false diagnosis of hypertension (OR: 2.76, 95% confidence interval: 1.96-3.89). Thus, clinic misjudgment of BP control may stem in part from high BP variability. Women with high BP variability are more susceptible to hypertension misdiagnosis. It is possible that high BP variability contributes to the increased cardiovascular risk related to both masked hypertension and white coat hypertension.

White-coat effect among older patients with suspected cognitive impairment: prevalence and clinical implications

OBJECTIVES

To evaluate the prevalence of white-coat effect (WCE), and its association with individual anxiety and insight of disease, among older patients evaluated for suspected cognitive impairment.

METHODS

This prospective cohort study, conducted in an Alzheimer Evaluation Unit, involved patients aged 55 years or older with suspected cognitive impairment. WCE was defined as a difference of at least 20 mmHg in systolic or 10 mmHg in diastolic blood pressure (BP) measured either by a physician during the visit or by a nurse (before and after the visit), compared with home self-blood pressure measurement (SBPM). Severity of cognitive impairment was evaluated through the Mini-Mental State Examination (MMSE); the Clinical Insight Rating Scale (CIR) and the Guidelines for the Rating for Awareness Deficits (GRAD) were used to evaluate the subject's insight; anxiety disorder was evaluated using the seven-question Generalized Anxiety Disorder scale (GAD-7).

RESULTS

Among 273 subjects, prevalence of WCE was 52%, 32.6% and 30.4%, according to physician and nurse BP measurements, respectively (p = 0.000). Prevalence of WCE did not differ between patients diagnosed with and without dementia, but was higher among patients with than in those without anxiety disorder (70.7% vs 38.2%, p = 0.000). Positive relations were observed between severity of anxiety and insight of disease, which were both inversely related with severity of cognitive impairment.

CONCLUSIONS

WCE is extremely common and is correlated to individual anxiety and insight of disease among older outpatients with suspected cognitive impairment; overestimation of hypertension severity might lead to unnecessary drug treatment and greater health costs in this setting.

Missed opportunities in diabetes management: a longitudinal assessment of factors associated with sub-optimal quality

BACKGROUND

In diabetic adults, tight control of risk factors reduces complications.

OBJECTIVE

To determine whether failure to make visits, monitor risk factors, or intensify therapy affects control of blood pressure, glucose, and lipids.

DESIGN

A non-concurrent, prospective study of data from electronic files and standardized abstraction of hard-copy medical records for the period 1/1/1999-12/31/2001.

PARTICIPANTS

Three hundred eighty-three adults with diabetes managed in an academically affiliated managed care program.

MEASUREMENTS

Main exposure variable: Intensification of therapy or failure to intensify, reckoned on a quarterly basis.

MAIN OUTCOME MEASURE

Hemoglobin A1c (A1c), systolic blood pressure (SBP), and LDL-cholesterol at the end of the interval.

RESULTS

In this visit-adherent cohort, control of glycemia and lipids showed improvement over 24 months, but many patients did not achieve targets. Only those with the worst blood pressure control (SBP >or=160 mmHg) showed any improvement over 2 years. Failure to intensify treatment in patients who kept visits was the single strongest predictor of sub-optimal control. Compared to their counterparts with no failures of intensification, patients with failures in >or=3 quarters showed markedly worse control of blood glucose (A1c 1.4% higher: 95% CI: 0.7, 2.1); hypertension (SBP 22.2 mmHg higher: 95% CI: 16.6, 27.9) and LDL cholesterol (LDL 43.7 mg/dl higher: 95% CI: 24.1, 63.3). These relationships were strong, graded, and independent of socio-demographic factors, baseline risk factor values, and co-morbidities.

CONCLUSIONS

Failure to intensify therapy leads to suboptimal control, even with adequate visits and monitoring. Interventions designed to promote appropriate intensification should enhance diabetes care in primary practice.

Clinical implications of white-coat effect among patients attending at a lipid clinic

We evaluated clinical implications of the white-coat effect (WCE) in cardiovascular (CV) risk stratification in the primary prevention setting of a Lipid Clinic. We compared home self blood pressure measurement (SBPM) with office blood pressure (BP) readings and BP measured by a nurse before and after the visit on consecutive subjects, free of previous CV diseases, attending at a Lipid Clinic for a first visit. Additionally, we evaluated whether and to what extent the difference between these measurements affect the 10-year cardiovascular risk calculated according to current guidelines. Mean home self-measured systolic and diastolic BP values were significantly lower than physician's and nurse's readings (p=0.000). A WCE was observed in 60.3% of patients during the physician's visit, and in 33.9% and 36.6% of nurse's measurements before and after visit, respectively. Compared with computation of SBPM, inclusion in risk predictive model of systolic BP values obtained by physician and nurse (before or after visit) resulted in significantly higher calculated CV risk (p=0.000) and in a higher risk-class allocation in 16.5%, 8.5% and 9.4% of patients, respectively (p=0.000). Our findings show that among patients attending at a Lipid Clinic there is a high prevalence of WCE, which is roughly halved when nurse's BP measurements were considered. Nurse's BP measurements before or after the doctor's visit may reduce, but not eliminate at all, the clinic overestimation of BP. The WCE associated with physician's office visit carries a substantial probability of 10-year CV risk overestimation in the primary prevention setting.

Masked hypertension in diabetes mellitus: a potential risk

The prevalence and clinical significance of masked hypertension (MHT) in diabetics have infrequently been described. The authors assessed the association of MHT (defined using a clinic blood pressure [BP] <140/90 mm Hg and daytime ambulatory BP > or = 135/85 mm Hg) with microvascular and macrovascular end organ damage in 81 clinically normotensive Japanese diabetic persons. The prevalence of silent cerebral infarcts (SCIs), increased left ventricular mass, and albuminuria were evaluated. Of 81 patients, 38 (46.9%) were classified as having MHT and showed significantly more SCIs (mean +/- SE: 2.5+/-0.5 vs 1.1+/-0.2; P=.017), and more albuminuria (39% vs 16%; P=.025), but no increase in left ventricular mass index, than the normotensive persons in office and on ambulatory BP monitoring group. The prevalence of MHT in this diabetic population was high (47%). Diabetic patients with MHT showed evidence of brain and kidney damage. Hence, out-of-office monitoring of BP may be indicated in diabetics whose BP is normal in the clinic.

Estimate of white-coat effect and arterial stiffness

OBJECTIVES

Blood pressure (BP) measured in the office is usually higher than the average ambulatory BP, a difference generally taken as an estimate of the white-coat effect. This study was designed to assess whether such a difference is associated with impairment of the conduit arterial system.

METHODS

We calculated the difference between office and average daytime peak systolic blood pressure (DeltaSBP) in 2778 hypertensive participants (1240 women) of the Progetto Ipertensione Umbria Monitoraggio Ambulatoriale cohort. Arterial stiffness was evaluated using an adjusted office pulse pressure to stroke volume ratio (PP/SV), measured at rest, which has previously been shown to predict cardiovascular outcome independent of echocardiographic left ventricular hypertrophy. Effective arterial elastance was also estimated.

RESULTS

Across quintiles of PP/SV, significant linear, positive trends were found with age, the proportion of women, plasma glucose and triglyceride levels (0.05 > P < 0.0001). Heart rate measured in the office increased mildly with quintiles of PP/SV (P < 0.05). After adjusting for age, sex, body weight and office heart rate, DeltaSBP progressively increased with increasing quintiles of PP/SV (P for trend < 0.0001), whereas stroke volume decreased, paralleling the increase in left ventricular relative wall thickness (both P < 0.0001) and left ventricular mass index (P < 0.05). The significant increase in effective arterial elastance with quintiles of PP/SV was also independent of peak systolic BP, in addition to age, sex, heart rate and body weight.

CONCLUSIONS

The difference between office BP and ambulatory BP, an estimate of the white-coat effect, is strongly associated with increased arterial stiffness, evaluated by a two-element fluid system accumulator.

Assessment of long-term antihypertensive treatment by clinic and ambulatory blood pressure: data from the European Lacidipine Study on Atherosclerosis

OBJECTIVES

Information on the features of long-term modifications of clinic and 24-h ambulatory blood pressure (ABP) by treatment is limited. The present study aimed to address this issue.

METHODS

Ambulatory BP monitoring and clinic BP (CBP) measurements were performed at baseline and at yearly intervals over a 4-year follow-up period in 1523 hypertensives (56.1 +/- 7.6 years) randomized to treatment with lacidipine or atenolol in the European Lacidipine Study on Atherosclerosis (ELSA).

RESULTS

CBP was always greater than ABP, while reductions in all BP values (greater for CBP than for ABP) were on average maintained throughout 4 years, CBP changes showing limited relationship with ABP changes (r = 0.14-0.27). BP reductions by treatment during daytime and night-time were correlated (r = 0.63-0.73). BP normalization was achieved in a greater percentage of patients for CBP (41.7%) than for ABP (25.3%), with systolic BP control being always less common than diastolic BP control. BP normalization was more frequent at single yearly visits than throughout the 4 years. Twenty-four-hour BP variability was reduced by treatment over 4 years in absolute but not in normalized units.

CONCLUSIONS

The present study provides the best evidence available on long-term effect of antihypertensive treatment on both ABP and CBP. On average, ABP was sustainedly reduced by treatment throughout the follow-up period, but 24-h BP was more difficult to control than CBP. In several patients, ABP control was unstable between visits, the percentage of patients under control over 4 years being much less than that of those controlled at each year. Treatment induced a reduction in absolute but not in normalized BP variability estimates. This has clinical implications because of the prognostic importance of ABP mean values and variability.

Introversion associated with large differences between screening blood pressure and home blood pressure measurement: The Ohasama study

OBJECTIVE

To explore the effect of personality on screening blood pressures measured in clinical settings and home blood pressure measurements.

METHODS

From 1997 to 1999, 699 participants underwent screening and home blood pressure measurements and completed the Japanese version of the short-form Eysenck personality questionnaire. An increased screening blood pressure was defined as screening blood pressure > or = 140/90 mmHg and an increased home blood pressure was defined as home blood pressure > or = 135/85 mmHg.

RESULTS

Participants with lower extroversion scores (i.e., introversion) showed a greater difference between screening and home systolic blood pressure. The association between introversion and differences was statistically significant, even after adjustment for other possible factors (younger age, female, wide screening pulse pressure, never smoked, and no antihypertensive medication). The adjusted means of SBP differences were 7.3 and 4.4 mmHg among the lowest and highest extroversion quartiles, respectively (P for trend = 0.02). Other personality scores (psychoticism or neuroticism) were not associated with screening and home blood pressure differences. The incorporation of an extroversion score in the basic model consisting of the above factors that affected the difference between screening and home blood pressure slightly improved the prediction of a high home blood pressure. The area under the receiver operating characteristic curve increased by 0.037 among participants with high screening blood pressure and 0.006 for those with normal screening blood pressure compared with the basic model.

CONCLUSION

Physicians may need to be aware of 'introverted' patients who have high blood pressure in clinic settings, because they have the potential for 'white-coat' hypertension.

Blood pressure at rest, during 24 h monitoring and in response to sympathetic stimulation in hypertensive patients with metabolic syndrome

OBJECTIVE

As subjects with metabolic syndrome have an increased sympathetic activity regardless of the presence of arterial hypertension, this study aimed at evaluating in hypertensives whether this condition has repercussions on differences in resting, ambulatory and under sympathetic stimulation blood pressure levels.

METHODS

Blood pressure (BP) was measured at rest and in response to isometric exercise and cold pressure test by zero-random sphygmomanometer. Moreover 24 h BP monitoring was performed by using Spacelabs 90207.

RESULTS

Of the 340 hypertensive patients entering the study, 110 (32%) had metabolic syndrome. They were older (47 vs. 42 years, p<0.01) than those without MS and, by definition, had increased body mass index, fasting blood glucose and triglycerides and lower HDL-cholesterol. Also BP at rest (148/95 vs. 140/90 mm Hg, p<0.01), during 24 h (138/89 vs. 129/84 mm Hg, p<0.001) as well as during daytime and nighttime were significantly increased in this group. No difference, on the other hand, was detected in the response to tests stimulating sympathetic nervous system and in the clinic-daytime BP difference.

CONCLUSIONS

In the present study hypertensive patients with MS have higher BP, both at rest and during ambulatory monitoring in comparison to hypertensives without MS. The BP response to the stimulation of the sympathetic system seems, on the other hand, similar probably because the presence of hypertension in both groups masks during maximal stress the differences evident in less stressing conditions.

Estimation of base blood pressure by using a new device in the outpatient clinic

Direct measurement of intra-arterial blood pressure (BP) for 24-h provides approximately 100,000 values that vary enormously, but each (BPi) can be expressed by the equation BPi = BP0 + DeltaBPi (BP0, base BP; DeltaBPi, BP increment, i=1, 2, ..., 100 x 10(3)). About 20% of outpatients with hypertension exhibit white-coat hypertension (WCH). In such patients, DeltaBPc (i = c; c, time at the clinic) is surmised to be large. A method for explaining the physiological factors in DeltaBPc and the estimation of base BP in the outpatient clinic is important. This study addresses this issue. A total of 293 subjects were divided into four groups: 1) WCH group, 45 individuals (office BP > or = 140/90 mmHg and 24-h indirect BP < 125/80 mmHg); 2) normotensive (NT) group, 84 controls matched for age and sex; 3) WHO-I group, 95 hypertensive patients with WHO stage I (office BP > or = 140/90 mmHg and 24-h BP > or = 125/80 mmHg); and 4) WHO-II group, 69 hypertensive patients with WHO stage II. Their BPc and heart rate (HR; HRc, clinic HR) values were measured by a BP-ECG monitoring device in the outpatient clinic. Power-spectral analysis was used to obtain the ratio between the low-frequency component (LF) and high-frequency component (HF) of ECG-RR variability (LF/HF = LH). Twenty-four-hour indirect BP (and BP0) and base HR (HR0) were measured by a portable device (TM2425) at 30-min intervals. Then, DeltaBPc (= BPc - BP0) was estimated by performing linear multivariate analysis applying the model equation DeltaBPc = (BPc -alphaLH)(1-betaHR0/HRc) + epsilon to the above variables (alpha and beta, constant values; epsilon, error). This model equation made it possible to estimate BP0 (and DeltaBPc) with a high coefficient of correlation (r > or = 0.85, mean of error less than 0.82 +/- 5.9 mmHg). The predictive accuracy for discrimination between WCH and sustained hypertension (WHO-I and WHO-II groups) by this equation was 88%. The new DeltaBP-estimation device (BP-ECG monitor) enabled us to infer BP0 and is therefore useful in estimating WCH in the outpatient clinic.

White-coat hypertension in adults

White-coat hypertension is defined by the coexistence of persistently high office blood pressure (BP) with normal self-measured or ambulatory blood pressure. The prognostic impact of white-coat hypertension is a subject of debate. Cardiovascular morbidity seems to be lower in white-coat hypertension than in ambulatory hypertension, and, according to some but not all studies, is not dissimilar between white-coat hypertension and clinical normotension. In a large collaborative study including individual data from four prospective cohort studies, the incidence of stroke tended to increase in the white-coat hypertension group in the long run, crossing the hazard curve of the ambulatory hypertension by the ninth year of follow-up. These data raise the hypothesis, to be tested in future studies, that white-coat hypertension might not be a benign condition for stroke in the long term. Further studies are needed in order to: (1) test whether white-coat hypertension is really a benign condition for stroke in the long term; (2) compare, in patients with white-coat hypertension, a regimen based on life-style measures without drugs and a standard regimen consisting of life-style measures with the possible addition of drugs. On the basis of current evidence, it is reasonable to suggest a treatment based on life-style measures in the low-risk stratum of patients with white-coat hypertension under the conditions of correct definition, absence of comorbid conditions and target-organ damage, and adequate follow-up

Assessment of the white-coat effect

BACKGROUND

A limitation of blood pressure measurements made in the physician's office is the transient elevation in pressure seen in many patients that does not appear to be linked to target organ damage or prognosis. This has been labeled the 'white-coat effect' (WCE), computed as the difference between blood pressure measurements taken by the physician and the ambulatory level or resting measures. It is unclear, however, which resting measure is most appropriate. The awake ambulatory blood pressure is the most widely used. However, while arguably the most useful measure for prediction of clinical outcomes, it is less appropriate for use as a resting measure, because it is influenced by many factors, including posture and physical activity level. Resting levels taken in the clinic may also be elevated, and will therefore underestimate the WCE.

METHODS

We addressed this question by taking resting measures in a non-medical setting on the day before patients were seen at a Hypertension Clinic (day 1), and comparing these with resting measures taken on the following day, in the clinic before the patient saw the physician.

RESULTS

As predicted, the day 1 resting levels were lower than those taken in the clinic prior to seeing the physician (P < 0.05 and P < 0.001 for systolic and diastolic pressures, respectively) in both normotensive and hypertensive patients. Using the day 1 resting levels, the estimated WCE for hypertensive patients was 5.3/6.9 mmHg (systolic/diastolic blood pressures), compared with estimates, using the clinic resting levels, of 0.3/0.5 mmHg. The pattern of changes was different in normotensive patients and hypertensive patients, with the physician pressures being slightly lower than day 1 pressures in the former, and substantially higher in the latter. Heart rate changes were similar and modest in both groups.

CONCLUSION

The WCE may not just be limited to that narrow interval in which the patient actually sees the physician, but may generalize to the clinic setting, rendering a clinic 'resting' level invalid. While it is strongly positive in most hypertensive patients, it is frequently negative in normotensive patients. Our results suggest that improved methods of measuring blood pressure in the clinic setting are unlikely to resolve the confounding influence of the WCE, and that greater reliance will need to be placed on out-of-office monitoring.