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In the last three decades protocols for the validation of blood pressure measuring devices have been developed by the US Association for the Advancement of Medical Instrumentation, the British Hypertension Society, the German Hypertension League, the European Society of Hypertension Working Group on blood pressure Monitoring and the International Organization for Standardization. The European Society of Hypertension International Protocol required much smaller sample size than the other protocols, aiming to reduce the time, resources and cost of validation studies and thereby increase the number of validated devices. Given its specifications, the European Society of Hypertension International Protocol was adequate for 'high- and low-accuracy' devices, yet assessment of 'moderate accuracy' devices had high uncertainty with resultant high rate of device failure. Thus, devices validated using the European Society of Hypertension International Protocol should be considered to be as accurate as those validated with the previous Association for the Advancement of Medical Instrumentation or British Hypertension Society protocols. However, the European Society of Hypertension International Protocol did not allow subgroup evaluation (arm sizes, special populations, etc). The mission of the European Society of Hypertension International Protocol to promote the concept of validation has been well achieved, as almost double studies have been published using it than all the other protocols together. However, the maintenance of different validation protocols is confusing and therefore experts from the Association for the Advancement of Medical Instrumentation, European Society of Hypertension International Protocol and International Organization for Standardization have now developed the AAMI/ESH/ISO Universal Standard (ISO 81060-2:2018) as the recommended 21st-century procedure for worldwide application. The European Society of Hypertension Working Group has published a practical guide for using the Universal Standard. It is in the interests of all scientific bodies to propagate the Universal Standard and ensure its wide implementation.

Objective The aim of this study was to determine the accuracy of the PHILIPS DL8760, an oscillometric blood pressure (BP) measuring device designed for self-measurement in the general population according to the European Society of Hypertension International Protocol (ESH-IP) revision 2010. Participants and methods The PHILIPS DL8760 measures BP at the brachial level. The validation was performed in 33 subjects. The mean age of the participants was 55.8 ± 14 years. SBP 146.1 ± 26 mmHg (range: 103-193), DBP was 86.8 ± 17.0 mmHg (range: 47-123), and arm circumference was 28.3 ± 4.0 cm (range: 22-39). Results The PHILIPS DL8760 fulfilled the criteria of the ESH-IP by passing phases one and two for both SBP measurements and DBP measurements. The device overestimated SBP by 1.5 ± 5.0 mmHg and underestimated DBP by 0.7 ± 3.9 mmHg. Conclusion The PHILIPS DL8760 BP device, with its specially designed cuff covering a broad range of arm circumferences, fulfilled the requirements of the International Protocol Revision 2010.

Background Auscultatory measurement of office blood pressure (BP) by mercury sphygmomanometers (AuscBPM) is still the gold standard in clinical trials and registration studies for antihypertensive drugs. The increasing availability of accurate automated oscillometric BP measuring devices has offered new perspectives in this field, although their usefulness in drug studies has not been systematically tested yet.Methods During the course of Valsartan 320mg EU Registration Study we used an electronic automated oscillometric BP measuring device (eBPM) as an alternative to conventional AuscBPM. Altogether 3776 patients were randomized into a double-blinded actively controlled parallel group study in 303 centers, and 54 422 BP readings were recorded by the validated, electronic, automated oscillometric device OMRON 705IT with digital printouts. Terminal digit preference and preference at therapeutic cutoff points were evaluated. The data were compared with the results of an earlier valsartan study similar in design but based on conventional AuscBPM. Furthermore, based on a simulation, four strategies for automated BP measurement with varying number of office readings (3-5) were analyzed to define an optimal method to collect BP at office visits.Results eBPM eliminated terminal digit preference and dramatically reduced preferences for therapeutic cutoff points as compared with earlier valsartan trials with conventional AuscBPM. However, even with eBPM a minor bias with the therapeutic cutoff value was observed probably because of an observer bias during data documentation. The within-patient variability of three measurements sequentially taken at each visit was similar to other strategies including more measurements.Conclusion On the basis of our data, we suggest that eBPM is a suitable alternative to AuscBPM in clinical trials and registration studies, and may carry specific advantages. Automatic data transfer of recorded values to electronic patient files may further minimize observer bias. Manufacturers should consider such findings for the development of professional devices. Blood Press Monit 15: 188-194 (C) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

Objective To reach a consensus on the prognostic significance of new techniques of automated blood pressure measurement. Methods A Task Force on the prognostic significance of ambulatory blood pressure monitoring wrote this review in preparation for the Eighth International Consensus Conference (28-31 October 2001, Sendai, Japan). This synopsis was amended to account for opinions aired at the conference and to reflect the common ground reached in the discussions. Points of consensus (1) Prospective studies in treated and untreated hypertensive patients and in the general population have demonstrated that, even after adjusting for established risk factors, the incidence of cardiovascular events is correlated with blood pressure on conventional as well as ambulatory measurement. Ambulatory monitoring, however, significantly refines the prediction already provided by conventional blood pressure measurement. (2) White-coat hypertension is usually defined as an elevated clinic blood pressure in the presence of a normal daytime ambulatory blood pressure. Event-based studies in hypertensive patients have convincingly demonstrated that the risk of cardiovascular disease is less in patients with white-coat hypertension than in those with higher ambulatory blood pressure levels even after controlling for concomitant risk factors. Based on prognostic evidence, white-coat hypertension can now be defined as a conventional blood pressure that is persistently equal to or greater than 140/90 mmHg with an average daytime ambulatory blood pressure of below 135/85 mmHg. The issue of whether or not white-coat hypertension predisposes to sustained hypertension needs further research. (3) There is a growing body of evidence showing that a decreased nocturnal fall in blood pressure (< 10% of the daytime level) is associated with a worse prognosis, irrespective of whether night-time dipping is studied as a continuous or a class variable. (4) Intermittent techniques of ambulatory blood pressure monitoring are limited in terms of quantifying short-term blood pressure variability. Proven cardiovascular risk factors such as old age, a higher than usual blood pressure and diabetes mellitus are often associated with greater short-term blood pressure variability. After adjusting for these risk factors, some - but not all - studies have nevertheless reported an independent and positive relationship between cardiovascular outcome and measures of variability of daytime and night-time blood pressure, for example standard deviation. (5) Reference values for ambulatory blood pressure measurement in children are currently based on statistical parameters of blood pressure distribution. In children and adolescents, functional rather than distribution-based definitions of ambulatory hypertension have yet to be developed. (6) Several studies of gestational hypertension have shown that, compared with office measurement, ambulatory blood pressure monitoring is a better predictor of maternal and fetal complications. Pregnancy is a special indication for ambulatory monitoring so that the white-coat effect can be measured and pregnant women are not given anti hypertensive drugs unnecessarily. (7) Ambulatory pulse pressure and the QKD interval are measurements obtained by ambulatory monitoring that to some extent reflect the functional characteristics of the large arteries. The QKD interval is correlated with left ventricular mass, and ambulatory pulse pressure is a strong predictor of cardiovascular outcome. (8) Under standardized conditions, the self-measurement of blood pressure is equally as effective as ambulatory blood pressure monitoring in identifying the white-coat effect, but further studies are required to elucidate fully the prognostic accuracy of self-measured blood pressure in comparison with conventional and ambulatory blood pressure measurement. Conclusions Ambulatory blood pressure measurement refines the prognostic information provided by conventional blood pressure readings obtained in the clinic or the doctor's office, Longitudinal studies of patients with white-coat hypertension should clarify the transient, persistent or progressive nature of this condition, particularly in paediatric patients, in whom white-coat hypertension may be a harbinger of sustained hypertension and target-organ damage in adulthood. Finally, the applicability, cost-effectiveness and long-term prognostic accuracy of the self-measurement of blood pressure should be evaluated in relation to conventional blood pressure measurement and ambulatory monitoring. (C) 2001 Lippincott Williams Wilkins.

Three oscillometric devices for the self blood pressure measurement were evaluated according to the International Protocol of the European Society of Hypertension in three separate studies. The Omron M3 Intellisense and the Omron M2 Compact measures blood pressure (BP) at the brachial level; the Omron R3-I Plus measures BP at the wrist level.The International Protocol is divided into two phases and includes a total number of 33 participants on whom the validation is performed. In each study, and for each participant, four BP measurements were taken simultaneously by two observers using mercury sphygmomanometers alternately with three measurements with the tested device. The difference between the observers and the device BP values was calculated for each measurement. The 99 pairs of BP differences were classified into three categories (or =5,or =10,or =15 mmHg).All three tested devices passed the first and second phase of the validation process. The mean differences between the device and mercury readings were 1.9+/-3.0 and -1.0+/-2.3 mmHg for systolic and diastolic BP, respectively, for the Omron M3 Intellisense device, 2.5+/-5.4 and -2.3+/-3.6 mmHg for the Omron M2 Compact device, and 1.4+/-4.5 and 0.8+/-4.6 mmHg for the Omron R3-I Plus device.Readings of the Omron M3 Intellisense, the Omron M2 Compact and the Omron R3-I Plus, differing by less than 5, 10, and 15 mmHg fulfill the International Protocol requirements and therefore can be used by patients for self blood pressure measurement.

Two electronic devices for self-measurement of blood pressure - a brachial monitor, the Omron M6, and a wrist monitor, the Omron R7 - were evaluated in two separate studies according to the International Protocol of the European Society of Hypertension.The International Validation Protocol is divided into two phases: the first phase is performed on 15 selected participants (45 pairs of blood pressure measurements); if the device passes this phase, 18 supplementary participants are included (54 pairs of blood pressure measurements) making a total number of 33 participants (99 pairs of blood pressure measurements) on whom the final validation is performed.The same methodology recommended by the European Society of Hypertension protocol was applied for both studies. In each study and for each participant, four blood pressure measurements were taken simultaneously by two trained observers using mercury sphygmomanometers alternately with three measurements taken by the tested device. The difference between the blood pressure value given by the device and that obtained by the two observers (mean of the two observers) was calculated for each measure. The 99 pairs of blood pressure differences were classified into three categories (or=5,or=10 andor=15 mmHg). The number of differences in each category was compared with the number required by the International Protocol. An individual analysis was then done to determine the number of comparisonsor=5 mmHg for each participant. At least 22 of the 33 participants should have two of their three comparisonsor=5 mmHg.In both studies, the two tested devices passed the first and the second phases of the validation process. The average differences between the device and mercury sphygmomanometer readings were 0.8+/-2.7 and -1.9+/-3.3 mmHg for systolic and diastolic blood pressure, respectively, for the Omron M6 device, and 0.2+/-4.2 and 0.2+/-2.9 mmHg for systolic and diastolic blood pressure, respectively, for the Omron R7 device. For both devices, readings differing by less than 5, 10 and 15 mmHg for systolic and diastolic blood pressure values fulfill the recommendation criteria of the International Protocol as well as the individual analysis.The Omron M6 (HEM-7001-E) and the Omron R7 (HEM 637-IT) devices fulfilled the validation recommendations of the International Protocol.

This paper, which summarizes the conclusions of a WHO Expert meeting, is aimed at proposing indications to develop technical specifications for an accurate and affordable blood pressure measuring device for office/ clinic use in low resource settings. Blood pressure measuring devices to be used in low resource settings should be accurate, affordable, and easily available worldwide. Given the serious inherent inaccuracy of the auscultatory technique, validated and affordable electronic devices, that have the option to select manual readings, seem to be a suitable solution for low resource settings. The agreement on the technical specifications for automated blood pressure measuring devices for office/ clinic use in low resource settings included the following features; high accuracy, adoption of electronic transducers and solar batteries for power supply, standard rates of cuff inflation and deflation, adequate cuff size, digital display powered by solar batteries, facilities for adequate calibration, environmental requirements, no need of memory function, resistance to shock and temperature changes, and low cost. Availability of a device with these features should be accompanied by adequate training of health care personnel, who should guarantee implementation of the procedures recommended in recent European and American Guidelines for accurate blood pressure measurement. © 2005 Lippincott Williams & Wilkins.

The Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Ireland, dabl Ltd., Blackrock Co., Dublin, Ireland, Hypertension Center, Third University Department of Medicine, Sotiria Hospital, Athens, Greece, Istituto Scientifico Ospedale San Luca, IRCCS, Instituto Auxologico Italiano, Milan, Italy, Societe Francaise d’Hypertension Arterielle, Filiale de la Societe Francaise de Cardiolgie, Paris, France, The Department of Clinical Pharmacology and Therapeutics, Tohoku University Graduate School of Pharmaceutical Science and Medicine, Sendai, Japan, Centre for Epidemiological Studies and Clinical Trials, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China, University Clinic Bonn, Department of Internal Medicine, Bonn, Germany and Guy’s and St Thomas’ Hospitals, London, UK

Background The aim of this study was to validate the Omron HEM-907 blood pressure (BP) measuring device according to the international validation protocol. Design The international validation protocol is divided into two phases: the first phase is performed on 15 selected subjects and if the device passes this phase, 18 more subjects are selected making a total number of 33 subjects on which the final validation is performed. Methods For each subject, BP measurements were performed simultaneously by two trained observers using mercury sphygmomanometers alternately with the Omron HEM-907 device. In all, 99 measurements were obtained for comparison. The difference between the BP value given by the device and that obtained by the two observers (mean of the two observers) was calculated for each measure. Results The difference between the two observers was -1 +/- 2 mmHg for the systolic BP (SBP) and for the diastolic BP (DBP). The Omron HEM-907 passed the first phase of the validation process. For the second phase, the average differences between the device and mercury sphygmomanometer readings were -1 +/- 7 and -5 +/- 6 mmHg for SBP and DBP respectively. Readings for the HEM-907 device differed by less than 5 mmHg for 61 of the systolic readings and 52 of the diastolic readings; by less than 10 mmHg for 85 of the systolic readings and 85 of the diastolic readings; and by less than 15 mmHg for 94 of the systolic readings and 96 of the diastolic readings. Conclusions The Omron HEM-907 device passes the two phases of the international validation protocol.

Working Group on Blood Pressure Monitoring of the European Society of Hypertension International Protocol for validation of blood pressure measuring devices in adults Eoin O’Brien,Thomas Pickering, Roland Asmar, Martin Myers, Gianfranco Parati, Jan Staessen, Thomas Mengden, Yutaka Imai, Bernard Waeber and Paolo Palatini and with the statistical assistance of Neil Atkins and William Gerin, on behalf of the Working Group on Blood Pressure Monitoring of the European Society of Hypertension

Self-measurement of blood pressure (SMBP) is increasingly used to assess blood pressure outside the medical setting. A prerequisite for the wide use of SMBP is the availability of validated devices providing reliable readings when they are handled by patients. This is the case today with a number of fully automated oscillometric apparatuses. A major advantage of SMBP is the great number of readings, which is linked with high reproducibility. Given these advantages, one of the major indications for SMBP is the need for evaluation of antihypertensive treatment, either for individual patients in everyday practice or in clinical trials intended to characterize the effects of blood-pressure-lowering medications. In fact, SMBP is particularly helpful for evaluating resistant hypertension and detecting white-coat effect in patients exhibiting high office blood pressure under antihypertensive therapy. SMBP might also motivate the patient and improve his or her adherence to long-term treatment. Moreover, SMBP can be used as a sensitive technique for evaluating the effect of antihypertensive drugs in clinical trials; it increases the power of comparative trials, allowing one to study fewer patients or to detect smaller differences in blood pressure than would be possible with the office measurement. Therefore, SMBP can be regarded as a valuable technique for the follow-up of treated patients as well as for the assessment of antihypertensive drugs in clinical trials.

This study compared the effects of morning and evening dosing of amlodipine/valsartan combination on 24-h blood pressure (BP) in patients uncontrolled by amlodipine (5 mg).This was a multicenter study that used a prospective, randomized, open-label, blinded endpoint design. Patients with essential hypertension, who's ambulatory BP was uncontrolled after 4 weeks on amlodipine (5 mg) were randomized to receive amlodipine/valsartan (5/160 mg) for 8 weeks in the morning or evening (n=231, 232, respectively), with optional uptitration up to 10/160 mg after 4 weeks if the office BP was uncontrolled. A 30-h ambulatory BP measurement was taken at randomization and at the end of the study.Morning and evening dosing with amlodipine/valsartan had equivalent effects on systolic BP (mean 24 h, daytime, night-time, and 24-30 h) and diastolic BP (mean 24 h, daytime, night-time, and 24-30 h). There was a small difference in the night-time diastolic BP (-4.92 vs.-6.20 mmHg; P=0.02) and a slight but nonsignificant trend for higher BP reduction during daytime for morning intake and during night-time for evening intake. BP control rates based on 24-h ambulatory BP measurement values (120/80 mmHg) were similar between morning and evening dosing (47 vs. 45%).These results indicate that, in patients with BP uncontrolled by amlodipine (5 mg), morning and evening treatment with amlodipine/valsartan combination have similar effects on circadian BP, especially when 24-h mean values are considered.

BACKGROUND A high percentage of hypertensive patients present an arm circumference of over 32 cm; the use of a large cuff is therefore recommended. Validation studies are usually performed in the general population using a standard-size cuff. The aim of this study was to assess the accuracy of the Omron M7 device in a population with an arm circumference ranging from 32 to 42 cm. DESIGN A validation study was performed according to the International Protocol of the European Society of Hypertension. This protocol is divided into two phases: the first phase is performed on 15 selected participants (45 pairs of blood-pressure measurements); if the device passes this phase, 18 supplementary participants are included (54 pairs of blood-pressure measurements), making a total number of 33 participants (99 pairs of blood-pressure measurements), on whom the analysis is performed. METHODS For each participant, four blood-pressure measurements were performed simultaneously by two trained observers, using mercury sphygmomanometers fitted with a Y tube; the measurements alternated with three by the test device. The difference between the blood-pressure value given by the device and that obtained by the two observers (mean of the two observations) was calculated for each measure. The 99 pairs of blood-pressure differences were classified into three categories (

Background Two electronic devices for self-measurement of blood pressure at the brachial artery - the Seinex SE-9400 (Seinex Electronics Ltd, Belfast, UK) and the Microlife BP 3AC1-1 (Microlife Corporation, Berneck, Switzerland) -were evaluated in two separate studies according to the International Protocol of the European Society of Hypertension. Design The international validation protocol is divided into two phases: the first phase is performed on 15 selected participants (45 blood pressure measurements); if the device passes this phase, 18 supplementary participants are included (54 blood pressure measurements) making a total number of 33 participants (99 blood pressure measurements) on whom the final validation is performed. Methods The same methodology recommended by the European Society of Hypertension protocol was applied for both studies. In each study and for each participant, four blood pressure measurements were taken simultaneously by two trained observers using mercury sphygmomanometers alternately with three measurements by the tested device. The difference between the blood pressure value given by the device and that obtained by the two observers (mean of the two observers) was calculated for each measure. The 99 differences were classified into three categories ( ≤ 5, ≤ 10, ≤ 15 mmHg). The number of differences in each category was compared with the number required by the ESH protocol. An individual analysis was then done to determine, for each participant, the number of comparisons ≤ 5 mmHg. At least 22 of the 33 participants should have two of their three comparisons ≤ 5 mmHg. Results In both studies, the two tested devices passed the first phase of the validation process. For the complete analysis (phase 1 and phase 2), the average differences between the device and mercury sphygmomanometer readings were in the first study for the Seinex SE-9400 device 0.9′5.2 and -1.7′4.7mmHg for systolic and diastolic blood pressure, respectively, and - 0.2′4.5 and -2.0′4.8mmHg for the Microlife BP 3AC1-1 device in the second study. For both devices, readings differing by less than 5,10 and 15mmHg for systolic and diastolic blood pressure values fulfill the recommendation criteria of the International Protocol as well as the individual analysis. Conclusions The Seinex SE-9400 and the Microlife BP 3AC1-1 devices fulfilled the validation recommendations of the International Protocol.

BACKGROUND Two devices for self-measurement of blood pressure at the brachial artery-the Omron M5-I and the Omron 705IT-were evaluated according to the international protocol of the European Society of Hypertension. DESIGN The international validation protocol is divided into two phases: the first phase is performed on 15 selected subjects and if the device passes this phase, 18 supplementary subjects are included making a total number of 33 subjects on which the final validation is performed. METHODS For each subject, four blood pressure (BP) measurements were performed simultaneously by two trained observers using mercury sphygmomanometers alternately with three measurements by the tested device. The difference between the BP value given by the device and that obtained by the two observers (mean of the two observers) was calculated for each measure. The 99 differences were classified into categories (

In recent years, studies have shown that parameters derived from the arterial pressure wave other than systolic and diastolic blood pressure provide important information on cardiovascular status. Among these parameters, pulse pressure, arterial stiffness and heart rate have emerged as independent markers of cardiovascular risk in different populations. Although a number of studies have used casual measurements of these parameters in a clinic setting, others have focused on their assessment under ambulatory conditions. The pulse pressure represents the amplitude of the pressure wave signal (systolic minus diastolic blood pressure), higher pulse pressure values having been reported in patients possessing cardiovascular risk factors. Close associations between a high pulse pressure and several surrogate end-points have been described. Furthermore, epidemiological studies have shown that a high pulse pressure is an independent predictor of hard end-points in several populations. Arterial stiffness represents one of the major haemodynamic factors determining pulse pressure. Pulse wave velocity, measured from the initial upstroke of the pressure wave, constitutes an established index of arterial stiffness. Studies have reported stiffer arteries in patients with cardiovascular pathology even at an early stage of disease. Close correlations between arterial stiffness and several surrogate markers have been reported, and arterial stiffness and its changes have recently been shown to be an independent predictor of hard end-points in patients with a high cardiovascular risk. Methods to evaluate arterial stiffness under ambulatory conditions are emerging. Heart rate represents the frequency of the cyclical strain of the arterial wall, clinical studies having shown that ambulatory heart rate is correlated to several surrogate markers. A few epidemiological studies have analysed the value of ambulatory heart rate as an independent predictor of hard end-points, but their positive findings need to be confirmed. The analysis of the pressure wave thus allows the determination of several haemodynamic indices other than systolic and diastolic blood pressure. Pulse pressure, arterial stiffness and heart rate constitute other outcomes that may be useful as additional factors in risk assessment for future therapeutic decision-making.

Objective To determine whether diabetes, smoking and dyslipidaemia were associated with greater than normal stiffness of aortic walls in subjects with white-coat hypertension. Methods Arterial distensibility was assessed by automatic measurement of carotid-femoral PWV in 35 healthy normotensives, 46 white-coat hypertensives (WCH, clinic blood pressures > 140/90 mmHg, daytime blood pressures < 130/85 mmHg) and 81 ambulatory hypertensives (clinic blood pressures > 140/90 mmHg, daytime blood pressures greater than or equal to 130 mmHg systolic or greater than or equal to 85 mmHg diastolic, or both) all matched for age, sex and body mass index, Nineteen normotensives (subgroup A), 28 WCH (subgroup A) and 37 ambulatory hypertensives (subgroup A) had only one or no other major cardiovascular risk factor whereas 16 normotensives (subgroup B), 18 WCH (subgroup B) and 44 ambulatory hypertensives (subgroup B) had also some combination of non-insulin-dependent diabetes, a smoking habit and dyslipidaemia. Results Both for the WCH and for ambulatory hypertensives diabetes and dyslipidaemia (subgroups B) were associated with higher (P < 0.04) PWV (11.6 +/- 0.3 and 12.8 +/- 0.3 m/s, respectively) than for subgroups A (9.3 +/- 0.5 and 10.9 +/- 0.6 m/s, respectively). In contrast, PWV for WCH in subgroup A (9.3 +/- 0.5 m/s) did not differ (P > 0.35) from those for the normotensive subgroups A (9.2 +/- 0.3 m/s) and B (9.6 +/- 0.4 m/s), PWV was not correlated to levels of glycaemia, glycosylated haemoglobin and cholesterolaemia. Conclusions These results suggest that, both for ambulatory hypertensives and for WCH, diabetes and dyslipidaemia are associated with an impairment of arterial distensibility that can entail a greater than normal cardiovascular risk, which might dictate a more than usually stringent treatment of concomitant risk factors and possibly of high blood pressure. In contrast, PWV in WCH of the subgroup A did not differ from those in normotensives, reinforcing the hypothesis that WCH is associated with a benign cardiovascular outcome in the absence of other cardiovascular risk factors. (C) 2000 Lippincott Williams & Wilkins.

BACKGROUND Self-monitoring of the blood pressure by patients at home or in other nonclinical settings has become increasingly common in recent years. This phenomenon has been fueled in part by the increase in availability of automatic sphygmomanometers, which are now both affordable and easy for patients to use. BENEFITS OF SELF-MONITORING: Self-monitoring of the blood pressure can be an important adjunct to management of hypertension. The technique allows patients to participate more in their care. Self-measured values of blood pressure are more likely to be representative of the average daily blood pressure than is a clinic measurement and may be better related to hypertensive involvement of target organs and cardiovascular morbidity than is the clinic blood pressure. Finally, the self-monitoring of blood pressure has the potential to reduce the costs of hypertension-related care. LIMITATIONS OF SELF-MONITORING: There are several issues that prevent the more widespread use of self-monitoring of the blood pressure in clinical practice. First, devices marketed for use by patients have advanced technically during the 1990s, but many have not been subjected to rigorous clinical validation for precision and reliability (e.g. in terms of Association for the Advancement of Medical Instrumentation and British Hypertension Society guidelines). It is recommended that devices for measuring blood pressure used by patients at home be subjected to the same validation processes as those that are applied to ambulatory recordings. Second, although the upper limits of normal for self-monitored blood pressure of a general population can be defined statistically (it is approximately 135/85 mmHg), it is not yet possible to determine the normal self-monitored blood pressure because these values must be linked to classical clinical cardiovascular endpoints or outcomes. Third, the relationships among self-monitored, clinic, and ambulatory blood pressures are defined for some populations but their behaviors according to age, sex, ethnicity, and treatment status require further study. Fourth, several different schedules for self-monitoring of the blood pressure by patients have been used in clinical research and practice. It will be necessary to determine the optimal schedule and number of recordings required when patients perform self-monitoring of the blood pressure. Fifth, self-monitoring of the blood pressure in clinical trials of antihypertensive therapies is certainly feasible but has typically not been included in their design, either by investigators or by the pharmaceutical sponsors. Sixth, there have been data suggesting that self-monitoring of the blood pressure reduces the comprehensive costs associated with hypertension care on an annual basis. However, since most work on the economic impact of self-monitoring of the blood pressure has been performed in managed-care environments in the USA, it is not known whether this reduction in health-care costs would be applicable to other types of practice environments on a worldwide basis. CONCLUSIONS Self-monitoring of the blood pressure is at present useful as an adjunct measurement for the management of hypertensive patients and might provide benefits in clinical trials of antihypertensive therapy. Nevertheless, the available data on self-monitoring of the blood pressure are inadequate as grounds for clinicians to make primary diagnostic or therapeutic decisions and should not override the blood pressure obtained by clinical measurement or via ambulatory monitoring.

OBJECTIVE: To determine whether non-invasive ambulatory blood pressure is more reproducible and less affected by the placebo treatment than are clinic blood pressure measurements. METHOD: Thirty-four essential hypertensive outpatients were randomly allocated after a 4-week preselection period in two groups in a cross-over study design. One group received placebo for 4 weeks while the other formed the control group (reproducibility), then the treatments were exchanged for another 4 weeks. Clinic and ambulatory blood pressures were measured at three different times for each patient, namely bnefore the random allocation to groups and at the end of each period, using a mercury sphygmomanometer and 24 h non-invasive ambulatory blood pressure monitoring. RESULTS: Administration of placebo was accompanied by a significant reduction in systolic and diastolic clinic blood pressures (by 3.4+/-13 and 3.6+/-8 mmHg, respectively), but not in 24 h, daytime and night-time blood pressures. Circadian hourly blood pressure and heart rate curves were virtually superimposable. In the 13 placebo responder patients selected on the basis of clinic blood pressure, placebo decreased the clinic blood pressure and also reduced systolic and diastolic ambulatory blood pressures, mainly during the day period (by 5.2+/-6.2 and 4.89+/-7.8 mmHg, respectively). This effect is specific and related to the placebo administration because repetition of the measurements without any treatment showed no significant difference. To characterize at baseline the placebo responder patients, comparison with the non-placebo responders showed lower baseline values of ambulatory systolic blood pressure recorded during 24 h daytime and night-time in the placebo responder group. CONCLUSION: The 24 h ambulatory blood pressure average is not affected by placebo in the present group of patients but that a placebo effect occurs mainly during the daytime in patients who decreased their clinic blood pressure under placebo (placebo responders); the placebo-induced reduction in blood pressure is related to a specific effect of placebo and is independent from any alerting reaction or reproducibility hypothesis. This study clearly indicates the necessity of including placebo and ambulatory blood pressure monitoring in the therapeutic and pharmacological trials of antihypertensive drugs.

This session was devoted to the application of ambulatory blood pressure monitoring (ABPM) to evaluate the therapeutic efficacy of antihypertensive treatment. Several aspects of this large field have been discussed, but others, no less important, need to be treated and clarified in the future.

The session devoted to the usefulness of non-invasive ambulatory blood pressure monitoring (ABPM) in the evaluation of antihypertensive therapy allowed us to discuss a number of important issues. ABPM emerged as a widely accepted technique to measure blood pressure in clinical trials. Actually, it was generally considered to provide more valuable information than do conventional blood pressure readings obtained sporadically by a doctor. However, still debated was the way of analysing ABPM recordings. This was particularly true with respect to the proposal of considering separately responders and non-responders when assessing the quality of blood pressure control achieved during treatment.