Reproducibility and cost of blood pressure self-measurement using the 'Loaned Self-measurement Equipment Model'

OBJECTIVE: To determine the reproducibility and the cost of the Loaned Self-measurement Equipment Model for blood pressure. SUBJECTS: Seventy-five subjects with non-complicated essential hypertension, having an average age of 56.2 +/- 11 years, were evaluated. METHODS: The Loaned Self-measurement Equipment Model consists of a set of sphygmomanometers belonging to the clinic, loaned to patients for 3-day periods for them to carry out 27 readings, and then returned. Using a mercury sphygmomanometer, a nurse carried out office blood pressure readings during two visits. A month later, the same procedure was repeated under the same clinical conditions. The agreement between studies was assessed by correlation coefficients, coefficients of variation and standard deviation of the differences (SDD). RESULTS: The office blood pressure was 147 +/- 17/89 +/- 12 mmHg during visit A, and 145 +/- 16/88 +/- 11 mmHg during visit B. The self-measurement blood pressure was 139 +/- 16/84 +/- 10 mmHg during the first visit, and 136 +/- 15/84 +/- 11 mmHg during the second visit. In neither of the cases were the differences statistically significant. The correlation coefficients for the office and self-measurement systolic blood pressure were statistically significant (P = 0.018), while those for the diastolic blood pressure were not statistically significant. The SDD for self-measurement systolic blood pressure was 10.7, compared to 15.0 for the office blood pressure (P < 0.01). The comparison in the case of diastolic blood pressure was not significant. The cost of each loan was $5.85 (US dollars). CONCLUSIONS: The Loaned Self-measurement Equipment Model has a good short-term reproducibility, and the cost is reasonable.     

Arterial stiffness and blood pressure self-measurement with loaned equipment

BackgroundA cross-sectional study was carried out in 415 hypertensive and normotensive subjects to determine the correlation between loaned self-measurement blood pressure (LSEM), arterial stiffness, and the different factors that contribute to it.MethodsThe LSEM model consists of lending a number of sphygmomanometers, property of the clinic, to patients for 3-day periods. Arterial stiffness was evaluated using the carotid-to-femoral pulse wave velocity (PWV), using an automatic apparatus. To determine the importance of each of these factors, a multiple linear regression analysis was carried out.ResultsOf the total number of patients, 78% were women, the average age was 57 ± 12 years, 55.8% were hypertensive, and 38.8% were diabetic. The PWV average for the whole group was 12.1 ± 4.2 m/sec. The correlation coefficients between the PVW and the self-measurements were 0.49 (P < .001) for the pulse pressure, and 0.46 (P < .001) for the systolic blood pressure (BP), respectively. Both represented 13.0 % of the total variation. The diastolic BP obtained by self-measurement and the serum creatinine values also had an effect on the stiffness, with 2.3 % (P = .05) each one.ConclusionsThe pulse pressure readings with self-measurement correlate better with the arterial stiffness, compared with the readings taken in the office.     

A pressure-time index' for assessing the severity of essential hypertension.

OBJECTIVE: A new derivative of 24 h ambulatory blood pressure monitoring (ABPM) is introduced and its association with left ventricular mass index (LVMI) in essential hypertension is examined. PATIENT: population One hundred and fifty-three previously untreated essential hypertension patients. METHODS: Patients underwent casual blood pressure (BP) readings, 24 h ABPM and left ventricular echocardiographic assessment The following 24 h awake and sleep ABP variables were calculated: mean systolic and diastolic BP, systolic and diastolic BP loads (percentage of systolic readings > 140/120 mmHg (day/ night) and diastolic readings > 90/80 mmHg (day/night)), standard deviation of systolic and diastolic ABP and nocturnal fall of systolic BP, as well as the integrated areas under the ABP curve. The area under the BP curve divided in horizontal slices was accurately modelled by a sigmoid curve. The parameters controlling the shape of the curve and in particular that regarding its 'slope' is hereafter called the 'pressure-time index'. RESULTS: 'Systolic pressure-time index 24 h' (SPTI24) is related to left ventricular mass index (multivariate analysis, P= 0.008). Using either partial correlation coefficients or a multivariate analysis, SPTI24 is related to left ventricular mass index, independently of age, casual blood pressure, mean systolic and diastolic ABP, systolic and diastolic BP loads, BP variability (standard deviation (SD), nocturnal fall of systolic BP) and integrated area under the curve (multivariate analysis, P= 0.004). CONCLUSIONS: In essential hypertension, the SPTI24 is related to LVMI independently of age, casual blood pressure, integrated area under the curve or any other derivative of 24 h ABPM, and might be used to assess the extent of hypertensive load.     

Accuracy of telemedical home blood pressure measurement in the diagnosis of hypertension

This study was conducted to compare the accuracy of clinic blood pressure (CBP) and telemedical home blood pressure (HBP) measurement in the diagnosis of hypertension in primary care. The study subjects were 411 patients with average CBP > or =140 mmHg systolic or > or =90 mmHg diastolic, who performed telemedical HBP measurement (5 days, four times daily) and ambulatory blood pressure (ABP) monitoring in random order. Main outcome measure was the agreement of CBP and HBP with daytime ABP. CBP was much higher than daytime ABP and average HBP (P<0.001) with no difference between the latter two. The correlation between CBP and ABP was weak (systolic: r=0.499, diastolic: r=0.543), whereas strong correlations existed between HBP and ABP (systolic: r=0.847, diastolic: r=0.812). A progressive improvement in the strength of the linear regression between average HBP of single days and ABP was obtained from day 1 to day 4, with no further benefit obtained on the fifth day. The HBP readings taken at noon and in the afternoon showed significantly stronger correlations with ABP than the blood pressures measured in the morning and in the evening. In conclusion, the accuracy of telemedical HBP measurement was substantially better than that of CBP in the diagnosis of hypertension in primary care. HBP most accurately reflected ABP on the fourth day of monitoring, and the readings at noon and in the afternoon seemed to be most accurate.     

Self-measured versus ambulatory blood pressure in the diagnosis of hypertension

OBJECTIVE: We examined to what extent self-measurement of blood pressure at home (HBP) can be an alternative to ambulatory monitoring (ABP) to diagnose white-coat hypertension. METHODS: In 247 untreated patients, we compared the white-coat effects obtained by HBP and ABP. The thresholds to diagnose hypertension were > or = 140/> or = 90 mmHg for conventional blood pressure (CBP) and > or = 135/> or = 85 mmHg for daytime ABP and HBP. RESULTS: Mean systolic/diastolic CBP, HBP and ABP were 155.4/100.0, 143.1/91.5 and 148.1/95.0 mmHg, respectively. The white-coat effect was 5.0/3.5 mmHg larger on HBP compared with ABP (12.3/8.6 versus 7.2/5.0 mmHg; P < 0.001). The correlation coefficients between the white-coat effects based on HBP and ABP were 0.74 systolic and 0.60 diastolic (P < 0.001). With ABP as a reference, the specificity of HBP to detect white-coat hypertension was 88.6%, and the sensitivity was 68.4%. CONCLUSION: Our findings are in line with the recommendations of the ASH Ad Hoc Panel that recommends HBP for screening while ABP has a better prognostic accuracy.     

Measurements of blood pressure with various techniques in daily practice: uncertainty in diagnosing office hypertension with short-term in-hospital registration of blood pressure.

OBJECTIVE: To predict blood pressure outside the clinic from a short-term in-hospital registration for patients referred for ambulatory blood pressure monitoring (ABPM) with special attention to office hypertension. PATIENTS AND METHODS: A series of measurements of blood pressure was performed by the same technician for 187 patients, 82% of whom were being administered antihypertensive therapy. She performed three mercury measurements of blood pressure (Hg stress 1) and then three manually started measurements with a semi-automatic device (Dinamap 1846SX; Dinamap stress) alternated with three manually started readings with a SpaceLabs 90207 monitor (SpaceLabs stress) on the contralateral non-dominant arm. The in-hospital session was continued with 15 automatic Dinamap registrations at 2 min intervals without the technician being present (Dinamap unstressed, five periods of three measurements averaged) before the patient left the hospital for 24h ABPM. RESULTS: The percentages of patients with hypertension in the office (systolic blood pressure >/= 140 mmHg or diastolic blood pressure >/= 90 mmHg, or both) were 80% with Hg stress 1, 76% with Dinamap stress and 85.0% with SpaceLabs stress. Average diastolic SpaceLabs stress was 6.0+/-5.6 mmHg (significantly) higher than diastolic Dinamap stress, whereas the difference between systolic blood pressures was 0.2+/-10.0 mmHg. No further change in blood pressure occurred after the fourth period of Dinamap unstressed measurements. Office hypertension defined as SpaceLabs stress systolic blood pressure >/= 140 mmHg or diastolic blood pressure >/= 90 mmHg, or both, and SpaceLabs daytime systolic blood pressure < 135 mmHg and diastolic blood pressure < 85 mmHg was found in 21 individuals. Office hypertension defined with similar cut-off points in the comparison of Dinamap stress versus Dinamap unstressed period 5 was found in 29 cases, 10 of which overlapped with the definition SpaceLabs stress versus SpaceLabs daytime. The differences between Dinamap stress and Dinamap unstressed period 5 were significantly correlated to the changes of SpaceLabs stress and SpaceLabs daytime both for systolic (r =0.41) and for diastolic (r =0.32) blood pressures. CONCLUSIONS: Measurements of blood pressure in the office with various techniques (mercury, Dinamap and SpaceLabs) are not equivalent. Office hypertension cannot be reliably predicted from a short-term semi-automatic in-hospital registration of blood pressure with a Dinamap device.     

Antihypertensive effect of valsartan 80 mg and hydrochlorothiazide 12.5 mg evaluated by ambulatory blood pressure monitoring

OBJECTIVE: The aim of the study was to evaluate by ambulatory blood pressure measurement (ABPM) the 24 hours antihypertensive efficacy of the fixed combination therapy, valsartan 80 mg + hydrochlorothiazide 12.5 mg (V + H), once daily, after 6 weeks of treatment, in patients with mild to moderate hypertension. STUDY DESIGN: It was a French, multicenter, double blind, randomized trial in parallel groups comparing V + H and placebo. After an initial two weeks placebo period, patients were assigned to receive either V + H or placebo for six weeks. Were eligible those with clinical arterial blood pressure, measured by sphygmomanometer, between 160/95 and 209/114 mmHg after monotherapy. A 26 hours ABPM, with Spacelabs 90,207, was done at J0 and J42 (one measurement every 15 minutes, in day time and at night). Responders were defined as a fall in day diastolic blood pressure > or = 5 mmHg and/or day diastolic blood pressure < 90 mmHg with ABPM. RESULTS: 123 of the 138 randomized patients had two interpretative measurements. Their average age was 59 + 10 years. 57% (78) of them were males and their average ABPM before treatment was 143 +/- 15/88 +/- 11 mmHg. With V + H, the reduction of the systolic and the diastolic blood pressure measured by ABPM, was significantly more important than with placebo (SBP: -15.4 +/- 10.9 mmHg versus -0.6 +/- 7.7 mmHg, p < 0.001; DBP: -9.1 +/- 7 mmHg versus -0.4 +/- 5.4 mmHg, p < 0.001). Pulse pressure (PP) was also significantly reduced with the combination therapy V + H, but it was not modified with placebo (-6.3 + 5.5 mmHg versus -0.2 + 4.1 mmHg, p < 0.001). ABPM responder rate was 73% with V + H versus 24% with placebo (p < 0.001). Trough/peak ratio was 80.3% for systolic blood pressure and 57.3% for diastolic blood pressure. The combination V + H was as well tolerated as placebo. CONCLUSION: The fixed combination V + H used for treatment of hypertension, after failure of monotherapy, is very effective in reducing pulse pressure, systolic and diastolic blood pressure, over 24 hours, homogeneously, and is as well tolerated as placebo.     

左室肥厚与单纯收缩,舒张或双期血压增高的关系

目的研究高血压病患者单纯收缩期（ＩＳＨ）、单纯舒张期（ＩＤＨ）或双相高血压（ＴＨ）上左室肥厚的关系。方法根据２４小时动态血压将病人分为４组：１．对照组（ｎ＝２７）平均收缩压＜１４０ｍｍＨｇ，平均舒张压＜９０ｍｍＨｇ；２．ＩＳＨ组（ｎ＝１６）平均收缩压＞１４０ｍｍＨｇ，平均舒张压＜９０ｍｍＨｇ；３．ＩＤＨ组（ｎ＝３１）平均收缩压＜１４０ｍｍＨｇ，平均舒张＞９０ｍｍＨｇ；４．ＴＨ组（ｎ＝１９）平均收缩压＞１４０ｍｍＨｇ和平均舒张压＞９０ｍｍＨｇ。超声心动图检测或计算舒张末期左室内径（ＥＤＤ）、室间隔及左室后壁厚度（ＬＶＳＴ，ＬＶＰＷＴ）、左室重量指数（ＬＶＭＩ）。结果ＩＳＨ、ＩＤＨ及ＴＨ组ＬＶＭＩ明显大于对照组Ｐ＜０．００１。ＩＳＨ和ＩＤＨ间、ＩＤＨ和ＴＨ组间无明显统计学差异。结论２４小时动态血压监测诊断为高血压病的患者ＬＶＭＩ明显大于偶测血压增高者。双期血压均高者左室肥厚最重。     

Validation of semi-automatic device UA-704 for self-measurement of blood pressure

OBJECTIVE: To perform a clinical validation for a semi-automatic arm-type device UA-704 (A&D Company, Ltd., Tokyo, Japan) according to the British Hypertension Society protocol. METHODS: Eighty-five study participants (37 men) were included. The mean age was 50.1+/-17.0 years, systolic blood pressure range was 79-212 mmHg and diastolic blood pressure range was 43-118 mmHg. For each participant, three readings of the UA-704 were compared with simultaneous auscultatory measurements by two trained independent observers. The observers used a mercury calibrated sphygmomanometer and a dual stethoscope. The results were graded according to the 1993 British Hypertension Society protocol. RESULTS: The average difference between mercury sphygmomanometer and UA-704 readings was -1.85+/-4.26 mmHg (mean+/-SD) for systolic blood pressure and -1.44+/-3.97 mmHg for diastolic blood pressure. The proportions of values agreeing to within 5, 10 and 15 mmHg were 79.2%, 96.5% and 99.6% for systolic blood pressure and 86.7%, 96.9% and 99.6% for diastolic blood pressure for the observers and device (A/A grade for British Hypertension Society). CONCLUSIONS: For an adult population, the UA-704 device for self-measurement of blood pressure achieved a British Hypertension Society grade A/A and therefore can be recommended for home blood pressure monitoring.     

Task force IV: Clinical use of ambulatory blood pressure monitoring. Participants of the 1999 Consensus Conference on Ambulatory Blood Pressure Monitoring

OBJECTIVE: To reach a consensus on the clinical use of ambulatory blood pressure monitoring (ABPM). METHODS: A task force on the clinical use of ABPM wrote this overview in preparation for the Seventh International Consensus Conference (23-25 September 1999, Leuven, Belgium). This article was amended to account for opinions aired at the conference and to reflect the common ground reached in the discussions. POINTS OF CONSENSUS: The Riva Rocci/Korotkoff technique, although it is prone to error, is easy and cheap to perform and remains worldwide the standard procedure for measuring blood pressure. ABPM should be performed only with properly validated devices as an accessory to conventional measurement of blood pressure. Ambulatory recording of blood pressure requires considerable investment in equipment and training and its use for screening purposes cannot be recommended. ABPM is most useful for identifying patients with white-coat hypertension (WCH), also known as isolated clinic hypertension, which is arbitrarily defined as a clinic blood pressure of more than 140 mmHg systolic or 90 mmHg diastolic in a patient with daytime ambulatory blood pressure below 135 mmHg systolic and 85 mmHg diastolic. Some experts consider a daytime blood pressure below 130 mmHg systolic and 80 mmHg diastolic optimal. Whether WCH predisposes subjects to sustained hypertension remains debated. However, outcome is better correlated to the ambulatory blood pressure than it is to the conventional blood pressure. Antihypertensive drugs lower the clinic blood pressure in patients with WCH but not the ambulatory blood pressure, and also do not improve prognosis. Nevertheless, WCH should not be left unattended. If no previous cardiovascular complications are present, treatment could be limited to follow-up and hygienic measures, which should also account for risk factors other than hypertension. ABPM is superior to conventional measurement of blood pressure not only for selecting patients for antihypertensive drug treatment but also for assessing the effects both of non-pharmacological and of pharmacological therapy. The ambulatory blood pressure should be reduced by treatment to below the thresholds applied for diagnosing sustained hypertension. ABPM makes the diagnosis and treatment of nocturnal hypertension possible and is especially indicated for patients with borderline hypertension, the elderly, pregnant women, patients with treatment-resistant hypertension and patients with symptoms suggestive of hypotension. In centres with sufficient financial resources, ABPM could become part of the routine assessment of patients with clinic hypertension. For patients with WCH, it should be repeated at annual or 6-monthly intervals. Variation of blood pressure throughout the day can be monitored only by ABPM, but several advantages of the latter technique can also be obtained by self-measurement of blood pressure, a less expensive method that is probably better suited to primary practice and use in developing countries. CONCLUSIONS: ABPM or equivalent methods for tracing the white-coat effect should become part of the routine diagnostic and therapeutic procedures applied to treated and untreated patients with elevated clinic blood pressures. Results of long-term outcome trials should better establish the advantage of further integrating ABPM as an accessory to conventional sphygmomanometry into the routine care of hypertensive patients and should provide more definite information on the long-term cost-effectiveness. Because such trials are not likely to be funded by the pharmaceutical industry, governments and health insurance companies should take responsibility in this regard.     

Office hypertension: abnormal blood pressure regulation and increased sympathetic activity compared with normotension

BACKGROUND: The percentage of patients with office or white-coat hypertension has been reported in international studies to be 20-30% of the hypertensive population. These patients can be identified and distinguished from patients with established hypertension by ambulatory blood pressure monitoring (ABPM) or self-measurement. There is still no satisfactory explanation for the phenomenon of 'office hypertension' and there are no data available to show how the blood pressure behaviour of office hypertensives differs from that of normotensive subjects away from the physician's office or clinic environment. OBJECTIVE: To investigate the blood pressure behaviour of patients with office hypertension away from the clinical setting over a 24 h period and to compare it with that of normotensive subjects. DESIGN AND METHODS: The blood pressure and heart rate of 36 patients with office hyhpertension and 33 normotensive subjects matched for age and sex were measured in a hypertension outpatient clinic and over 24 h using ABPM. The ambulatory data were subjected both to conventional and to modern rhythm analysis. Urinary catecholamine excretion was measured as a marker of sympathetic activity. RESULTS: In the clinic, the patients with office hypertension had significantly (P < 0.01) higher blood pressure values (146/97 mmHg) than did the normotensive controls (128/81 mmHg). The conventional analysis as well as the rhythm analysis of the ABPM data revealed no difference between the two groups with respect to the 24 h, daytime or night-time mean values and SD. However, the rhythm analysis showed a higher maximum and a lower minimum value for systolic and diastolic blood pressures in the patients with office hypertension, resulting in a greater amplitude both of systolic and of diastolic blood pressure due to a significantly (P < 0.005 and P < 0.05) higher maximum minus minimum value (38/32 mmHg) compared with those of normotensive controls (29/28 mmHg). The early morning rise in systolic and diastolic blood pressures was significantly (P < 0.008 and P < 0.03) greater in the patients with office hypertension (11/9 versus 7/7 mmHg) and intersected the curve of the normotensive controls at approximately 0600 h. No significant differences in heart rate at any time were observed between the groups. The urinary excretion of noradrenaline and dopamine was significantly (P < 0.01 and P < 0.05) increased during daytime for the office hypertensives. CONCLUSION: Patients with office hypertension, who by definition do not yet have established hypertension, already exhibit abnormal regulation both of systolic and of diastolic blood pressure during the morning period and daytime, with a significantly greater early morning rise compared with normotensive subjects and a greater blood pressure amplitude (amplitude hypertension) due to lower blood pressure during night-time and higher blood pressure during the day with increased sympathetic activation. Office hypertension seems to be the earliest manifestation of hypertension.     

Evaluation of a short home blood pressure measurement in an outpatient population of hypertensives

Current guidelines suggest the use of home blood pressure monitoring (HBPM) as a method complementary to ambulatory blood pressure monitoring (ABPM) for the identification of arterial hypertension. A cross-sectional study was conducted to evaluate the accuracy of a short HBPM schedule compared with ABPM, and to evaluate to what extent HBPM can replace ABPM. A total of 310 patients who performed ABPM in our hypertension clinic were enrolled between November 2011 and June 2015. They performed a 4-day HBPM schedule, with two readings in the morning and two readings at night. Results showed a moderate correlation between HBPM and ABPM (r = 0.59 for systolic blood pressure (SBP) and r = 0.72 for diastolic blood pressure (DBP)) and moderate diagnostic agreement (area under curve: 0.791 for SBP and 0.857 for DBP). No significant difference was found between first-day average and those of days 2–4. Diagnostic agreement between the two techniques was moderate, supporting the notion that HBPM cannot replace ABPM in the general population. However, we identified two HBPM thresholds, 123/75 and 144/87 mm Hg, through which subjects who may not require further ABPM can be identified.     

Is nurse-measured blood pressure a valid substitute for ambulatory blood pressure monitoring?

BACKGROUND: Because ambulatory blood pressure monitoring (ABPM) is not available everywhere, the objective of the study was to determine whether nurse-measured blood pressure could be an acceptable substitute to ABPM. METHODS: We analyzed the data of 2385 consecutive patients referred to our hypertension clinic for the performance of ABPM. Before ambulatory monitoring was performed, a nurse-measured BP was obtained three times using a Y-tube connecting the sphygmomanometer and the recorder. We compared the mean value of the three nurse-measured blood pressures with that of the 12h daytime ambulatory monitoring, considered as the reference. RESULTS: The difference between the nurse-measured and the ambulatory blood pressure was small but statistically significant, indicating that nurse-measured blood pressure tends to overestimate both diastolic and systolic blood pressure. The difference between the nurse blood pressure and ABPM was greater among treated hypertensive patients than untreated patients. To diagnose hypertension, defined as a blood pressure of over 140/90mmHg by ABPM, the positive predictive value of the nurse blood pressure was 0.81 and the negative predictive value 0.63. However, these predictive values could be improved with less stringent cut-off values of blood pressure. Thus, for a diastolic blood pressure above 100mmHg, the positive predictive value of nurse blood pressure was 0.55 and the negative predictive value 0.91. These figures were relatively similar for previously treated and untreated patients. CONCLUSION: Nurse blood pressure is less accurate than ABPM in diagnosing hypertension, defined as a blood pressure of over 140/90mmHg. It could, however, be an acceptable substitute, especially to exclude people who do not need to be treated, in situations where lower resources require a less rigorous definition of hypertension.     

Tele-monitoring of home blood pressure in treated hypertensive patients

AIM: To compare the accuracy of clinic blood pressure (CBP) and telemedical home blood pressure (HBP) measurement in the assessment of antihypertensive effect. METHODS: 362 patients on antihypertensive medication performed HBP measurement (5 days, duplicate measurements, four times daily) and ambulatory blood pressure (ABP) monitoring in random order. Main outcome measure was the agreement of CBP and HBP with daytime ABP. RESULTS: CBP was much higher than ABP and average HBP (p < 0.001). There was a progressive decline in HBP over the course of the study, achieving the level of daytime ABP on the last 2 monitoring days. The correlation between CBP and ABP was weak (systolic: r = 0.343, diastolic r = 0.430), whereas strong correlations existed between HBP and ABP (systolic r = 0.804, diastolic r = 0.776). A progressive improvement in the strength of the correlation between average HBP of single days and ABP was obtained over the 5 monitoring days. The HBP readings taken in the afternoon showed a stronger correlation with ABP than the values measured in the morning, at noon and in the evening. Averaging more HBP readings taken on succeeding days resulted in a progressive improvement in the agreement with ABP with a further benefit when readings of day 1 were included. CONCLUSIONS: The accuracy of telemedical HBP measurement is substantially better than that of CBP. The results suggest, that HBP should be measured for 5 days, and afternoon measurements should be preferred in assessing control of hypertension.     

A study of the white-coat phenomenon in patients with primary hypertension.

The objective of this study was to evaluate whether the discrepancy between clinic and home blood pressure (BP) in hypertensive subjects would disappear or diminish in magnitude if the BP measurement was taken under controlled conditions differing only with respect to location (clinic vs. home). Three hundred and sixty-seven patients aged 34-84 years with primary hypertension were enrolled. All of the patients or their spouses were taught to measure BP correctly with their own sphygmomanometer at home. The home BP value (HBP) was calculated as the average of 45 readings over 15 days. On days 6, 12, and 18 of the measurement period, rather than measuring their BP at home, patients and their spouses were asked to visit the hospital at the usual time of their BP measurement and to bring their own sphygmomanometer. The clinic BP value (CBP) was calculated as the average of the 9 readings taken on these visits by the patients or their spouses. The "white-coat phenomenon" (WCP) was considered to be present when the difference between the CBP and HBP was greater than 20/10 mmHg. The mean reading of home systolic/diastolic BP was 134.7/79.1 mmHg and the mean reading of clinic systolic/diastolic BP was 149.8/86.4 mmHg. In the total subject group, the prevalence rate of WCP was 31%-35% if the WCP was defined as DeltaBP (CBP - HBP) > or =20 mmHg/10 mmHg. In conclusion, ruling out the influence of different factors, including time of day, the sphygmomanometer, the individual taking the BP measurement, the climate, and the patients' health or mood, the WCP was still found to exist to a statistically significant degree. This study indicated that teaching patients to measure their own BP at home is an effective procedure to obtain a more accurate result of their BP level. It also helped to involve the patients more actively in controlling their hypertension.     

The international database of self-recorded blood pressures in normotensive and untreated hypertensive subjects.

OBJECTIVES: To pool data from individual subjects in an attempt to determine an operational threshold for making clinical decisions based on the self-recorded blood pressure (SRBP) and to examine how many hypertensive subjects, diagnosed by conventional blood pressure (CBP) measurement, would have a self-recorded blood pressure within the normotensive range if the proposed thresholds were applied. DATA SOURCES: Thirteen research groups studied 4668 untreated subjects. RESULTS: In total 2401 subjects were normotensive, 494 were borderline hypertensive and 1773 were definitely hypertensive. Hypertension had been diagnosed from the mean of 1-6 (median 3) CBP measurements obtained during 1-3 (median 1) visits. The reference values for SRBP measurements determined from the 95th percentiles of the distributions for normotensive subjects were 137 mmHg systolic and 85 mmHg diastolic. Of the subjects with systolic hypertension, 16% had systolic SRBP 相似文献   

Assessment of blood pressure in patients with Type 2 diabetes: comparison between home blood pressure monitoring, clinic blood pressure measurement and 24-h ambulatory blood pressure monitoring.

AIMS: To compare a home blood pressure (BP) monitoring device and clinic BP measurement with 24-h ambulatory BP monitoring in patients with Type 2 diabetes mellitus (DM). METHODS: Fifty-five patients with type 2 DM had BP measured at three consecutive visits to the DM clinic by nurses using a stethoscope and mercury sphygmomanometer (CBP). Twenty-four-hour ambulatory BP was measured using a Spacelabs 90207 automatic cuff-oscillometric device (ABPM). Subjects were then instructed in how to use a Boots HEM 732B semiautomatic cuff-oscillometric home BP monitoring device and measured BP at home on three specified occasions on each of 4 consecutive days at varying times (HBPM). RESULTS: Correlations between HBPM and ABPM were r = 0.88, P < 0.001 for systolic BP and r = 0.76, P < 0.001 for diastolic BP, with correlations between CBP and ABPM being systolic r = 0.59, P < 0.001, diastolic r = 0.47, P < 0.001. HBPM agreed with ABPM more closely compared with CBP (CBP +10.9/+3.8 (95% confidence intervals (CI) 6.9, 14.8/1.6, 6.1) vs. HBPM +8.2/+3.7 (95% CI 6.0, 10.3/2.0, 5.4)). The sensitivity, specificity and positive predictive value of HBPM in detecting hypertension were 100%, 79% and 90%, respectively, compared with CBP (85%, 46% and 58%, respectively). CONCLUSIONS: In patients with Type 2 DM, home BP monitoring is superior to clinic BP measurement, when compared with 24-h ambulatory BP, and allows better detection of hypertension. It would be a rational addition to the annual review process. Diabet. Med. 18, 431-437 (2001)     

Validation of the Microlife BP 3BTO-A oscillometric blood pressure monitoring device according to a modified British Hypertension Society protocol

BACKGROUND: The market for devices for the self-measurement of blood pressure is growing, and as accuracy is of prime importance, there is increasing pressure for manufacturers to provide evidence of independent testing. Recent reviews have shown that only five automated upper arm devices for self-measurement of blood pressure have been recommended for use. We tested the Microlife BP 3BTO-A, a lightweight, upper arm, automated oscillometric device, according to a modified version of the British Hypertension Society protocol and also analysed the computer-generated oscillograms for possible causes of inaccuracy. METHODS: One hundred and twenty-six subjects were recruited from general medical and specialist clinics and from amongst the staff at Guy's and St Thomas' Hospital, London, UK. Only 85 of these were included in the final analysis. Nine sequential readings were taken by two trained observers alternating between the mercury sphygmomanometer and the device. The last seven readings were analysed according to the British Hypertension Society protocol. Modifications to the protocol were: (1) the exclusion of patients whose blood pressure varied by more than 15 mmHg between sequential observer readings and (2) limited testing in the low systolic pressure range. RESULTS: The Microlife achieved a grade A for both systolic and diastolic pressure according to the British Hypertension Society protocol. The mean differences (standard deviation) between the observers and the device were -1.6 (7.7) mmHg and -2.1 (6.3) mmHg for systolic and diastolic blood pressure, respectively, therefore also fulfilling the criteria set by the Association for the Advancement of Medical Instrumentation. Sub-analysis for different pressure ranges showed that the device was less accurate in the high-pressure range (>160/100 mmHg). CONCLUSION: The Microlife can be recommended for clinical use in an adult population.     

The ambulatory blood pressure in normotensive and hypertensive subjects: results from an international database

Objective: To delineate more precisely an operational threshold for making clinical decisions based on ambulatory blood pressure (ABP) measurement by studying the ABP in subjects who were diagnosed as either normotensive or hypertensive by conventional blood pressure (CBP) measurement.Subjects: Twenty-four research groups recruited 7069 subjects. Of these, 4577 were normotensive (systolic CBP ≤ 140 mmHg and diastolic CBP ≤ 90 mmHg) and 1773 were hypertensive (systolic CBP ≥ 160 mmHg and/or diastolic CBP ≥ 90 mmHg). Of the latter, 1324 had systolic and 1310 had diastolic hypertension.Results: Ninety-five percent of the normotensive subjects had a 24-h ABP below (systolic and diastolic, respectively) 133 and 82 mmHg. Of the patients with systolic hypertension, 24% had a 24-h systolic ABP of < 133 mmHg. Similarly, 30% of those with diastolic hypertension had a 24-h diastolic ABP of < 82 mmHg. The probability that hypertensive patients had a 24-h ABP below these thresholds was higher in women than in men, increased with age and was 2- to 4-fold greater if the CBP of the patient had been measured at only one visit and if fewer than 3 CBP measurements had been averaged to establish the diagnosis of hypertension. By contrast, for each 10-mmHg increment in systolic CBP, this probability decreased by 54% for the 24-h systolic ABP and by 25% for the 24-h diastolic ABP, and for each 5 mmHg increment in diastolic CBP it increased by 6 and 9%, respectively.Conclusion: The ABP distributions of the normotensive subjects included in the present international database were not materially different from those in previous reports in the literature. One-fifth to more than one-third of the hypertensive patients had an ABP which was below the 95th centile of the ABP in normotensive subjects, but this proportion decreased if the hypertensive patients had shown a higher CBP upon repeated measurement. The prognostic implications of elevated CBP in the presence of normal ABP remain to be determined.     

Effects of age on hypertensive status in patients with chronic kidney disease

OBJECTIVE: To evaluate effect of age on hypertensive status in chronic kidney disease (CKD). METHODS: We studied 459 prevalent CKD patients (stages 2-5, no dialysis), grouped by age (< 55, 55-64, 65-74, >or= 75 years), undergoing clinical blood pressure (CBP) and ambulatory blood pressure (ABP) measurement. RESULTS: Prevalence of diabetes, left ventricular hypertrophy and previous cardiovascular disease progressively increased with aging; glomerular filtration rate (GFR) and hemoglobin decreased. Achievement of CBP target decreased from 16% in patients < 55 years to 6% in those >or= 75 years (P = 0.023). ABP 24-h systolic rose while diastolic decreased, with a consequent pulse pressure increase from 45 +/- 8 to 65 +/- 14 mmHg (P < 0.0001). Age, proteinuria, diabetes, cardiovascular disease and anemia but not GFR predicted higher 24-h pulse pressure. CBP overestimated systolic/diastolic daytime ABP by 14 +/- 18/7 +/- 11 mmHg on average, a greater difference in older than younger groups (P < 0.005). Conversely, CBP night-time ABP difference did not vary among groups (24 +/- 20/16 +/- 11 mmHg). These age-dependent differences determined a rising prevalence of white-coat hypertension (from 19 to 40%, P = 0.001) and night/day ratio of at least 0.9 (from 43 to 66%, P = 0.0004). Age, diabetes, left ventricular hypertrophy and anemia but not GFR predicted nondipping status. Among the oldest patients, 13% had diastolic CBP below 70 mmHg, with 48% below the corresponding values of daytime (< 69 mmHg) or night-time ABP (< 60 mmHg). CONCLUSION: In CKD, prevalence of white-coat hypertension, nondipping status and potentially dangerous low diastolic ABP increases with aging. This suggests wider use of ABP monitoring in older patients and need for trials addressing identification of an age-specific blood pressure target.