Portal de Periódicos da CAPES

Why Is Out-of-Office Blood Pressure Measurement Needed?

2009; Lippincott Williams & Wilkins; Volume: 54; Issue: 2 Linguagem: Inglês

10.1161/hypertensionaha.108.122853

1524-4563

Gianfranco Parati, Stefano Omboni, Grzegorz Bilo,

Hemodynamic Monitoring and Therapy

HomeHypertensionVol. 54, No. 2Why Is Out-of-Office Blood Pressure Measurement Needed? Free AccessArticle CommentaryPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessArticle CommentaryPDF/EPUBWhy Is Out-of-Office Blood Pressure Measurement Needed?Home Blood Pressure Measurements Will Increasingly Replace Ambulatory Blood Pressure Monitoring in the Diagnosis and Management of Hypertension Gianfranco Parati, Stefano Omboni and Grzegorz Bilo Gianfranco ParatiGianfranco Parati From the Department of Clinical Medicine and Prevention (G.P., G.B.), University of Milano-Bicocca, Milan, Italy; Centro Interuniversitario di Fisiologia Clinica e Ipertensione (G.P.), Milan, Italy; Department of Cardiology (G.P., G.B.), S Luca Hospital, Istituto Auxologico Italiano, Milan, Italy; Italian Institute of Telemedicine (S.O.), Varese, Italy. , Stefano OmboniStefano Omboni From the Department of Clinical Medicine and Prevention (G.P., G.B.), University of Milano-Bicocca, Milan, Italy; Centro Interuniversitario di Fisiologia Clinica e Ipertensione (G.P.), Milan, Italy; Department of Cardiology (G.P., G.B.), S Luca Hospital, Istituto Auxologico Italiano, Milan, Italy; Italian Institute of Telemedicine (S.O.), Varese, Italy. and Grzegorz BiloGrzegorz Bilo From the Department of Clinical Medicine and Prevention (G.P., G.B.), University of Milano-Bicocca, Milan, Italy; Centro Interuniversitario di Fisiologia Clinica e Ipertensione (G.P.), Milan, Italy; Department of Cardiology (G.P., G.B.), S Luca Hospital, Istituto Auxologico Italiano, Milan, Italy; Italian Institute of Telemedicine (S.O.), Varese, Italy. Originally published6 Jul 2009https://doi.org/10.1161/HYPERTENSIONAHA.108.122853Hypertension. 2009;54:181–187Other version(s) of this articleYou are viewing the most recent version of this article. Previous versions: July 6, 2009: Previous Version 1 Over the last decades, 2 main techniques for measuring blood pressure (BP) out of the physician's office have gained increasing importance in the clinical approach to arterial hypertension, both being supported by recent international hypertension management guidelines.1,2 These techniques are home BP monitoring (HBPM) and 24-hour ambulatory BP monitoring (ABPM). Their diffusion in clinical practice has been favored by a number of factors, including on one side technical progress and wider availability of accurate HBPM and ABPM devices and on the other side the increasing awareness of the limitations of office BP (Table 1).3,4 Office BP is in fact characterized by a random error affecting casual BP readings and by a systematic error related to the patient's alerting reaction to the measurement procedure and setting, known as "white coat effect."1,3 Both ABPM and HBPM are devoid of these limitations and, thus, provide more stable and reproducible information on BP values,5 which is also of greater prognostic relevance6–21 (Table 2). Furthermore, office BP readings are unable to collect information on BP during a subject's usual activities and over a long period of time,22 an important limitation in everyday management of hypertensive subjects that can be overcome by out-of-office BP monitoring. Table 1. Comparison of Main Features of 3 Main Methods of BP MeasurementFeatureOffice BPABPMHBPMData are from Reference,6 modified WCH indicates white coat hypertension; MH, masked hypertension.No. of readingsLowHighMediumWhite coat effectYesNoNoOperator dependencyYesNoNoNeed of device validation (yes if oscillometric device used)NoYesYesDaytime BP++ + ++ +Nighttime BP and dipping−+ + +−Morning BP±+ ++24-h BP variability−+ +±Long-term BP variability−±+ +WCH and MH diagnosis−+ ++ +Placebo effect+ +−−ReproducibilityLowHigh (24-h average values)High (average of several values)Prognostic value++ + ++ +Patient involvement−−+ +Need of patient training−±+ +Physician involvement+ + ++ ++Patient acceptance+ +±+ +Monitoring of treatment effectsLimited informationExtensive information on diurnal BP profile, cannot be repeated frequentlyAppropriate for long-term monitoring, limited information on BP profileHypertension control improvement++ ++ + +CostLowHighLowAvailabilityHighLowHighTable 2. Home BP Measurements and OutcomeStudy NamePopulationOutcomeSHEAF indicates Self-Measurement of Blood Pressure at Home in the Elderly; PAMELA, Pressioni Arteriose Monitorate e Loro Associazioni; CDK, chronic kidney disease. Data are from Reference,6 by permission.Ohasama8,11Treated and untreated general population aged ≥40 yCardiovascular, noncardiovascular, and all-cause mortalityOhasama12Treated and untreated general population aged ≥40 yTotal stroke morbidityOhasama13Treated and untreated general population aged ≥40 yTotal stroke morbidityOhasama14Treated and untreated general population aged ≥40 yTotal, hemorrhagic, and ischemic stroke morbidityOhasama15Treated and untreated general population aged ≥40 yTotal stroke morbidityKahoku16Treated and untreated community-dwelling elderly individuals aged ≥65 yCardiovascular, noncardiovascular and all-cause mortalityKahoku17Treated and untreated community-dwelling elderly individuals aged ≥75 yDisability, cardiovascular and all-cause mortality, cardiovascular and stroke morbiditySHEAF18Treated hypertensive patients aged ≥60 yCardiovascular and all-cause mortality, total cardiovascular morbidityPAMELA9,10Treated and untreated general population aged 25–74 yCardiovascular and all-cause mortalityCKD veterans19Treated veterans with chronic kidney diseaseMorbidity of end stage renal disease, all-cause mortalityFlanders20Treated and untreated general population aged ≥60 yMajor cardiovascular events (cardiovascular death, myocardial infarction, and stroke)Didima21Treated and untreated general population aged ≥18 yTotal cardiovascular morbidity and mortalityABPM was initially confined to specialized hypertension centers because of its relatively high cost, but over the years its availability has steadily increased. HBPM, on the other hand, has been used rather reluctantly by physicians in routine management of hypertensive patients. Although its potential usefulness in clinical practice was acknowledged many years ago,23 its application has been limited until the end of last century by the need to use auscultatory measurements, an approach that is difficult to apply correctly,24 particularly in the home setting, and prone to providing inaccurate information, especially when using aneroid devices.25 A major breakthrough came with the introduction of inexpensive, easy-to-use, and accurate automated oscillometric BP measuring devices, leading to a widespread use of HBPM. At present, in developed countries ≈70% of hypertensive patients regularly assess their BP at home,26,27 and the clinical usefulness of this approach is generally acknowledged by physicians.28,29Such a rapidly growing diffusion of HBPM in clinical practice has inevitably raised the question of whether HBPM and ABPM should be considered as alternative methods to obtain the same information or whether instead they represent sources of complementary data. In the former case, the use of ABPM, this approach being a more expensive and more difficult technique, could hardly be justified. This important issue is still being debated, and our article is aimed at providing a contribution to this discussion.Similarities Between HBPM and ABPMThe most important common denominator of HBPM and ABPM is the fact that they both provide out-of-office BP values, ie, BP values obtained in the patient's "natural" environment. Thus, these values are basically devoid of the alarm reaction associated with office BP measurement, responsible for the white coat effect.30,31 Another important common advantage of ABPM and HBPM is that, when current recommendations are followed, they both make use of automated, validated oscillometric devices.6,7,32 This makes the obtained BP values operator independent, thus avoiding some common limitations affecting office measurements.33 Importantly, the application of these techniques is possible in a vast majority of cases, the 2 most relevant exceptions including important arrhythmias, eg, frequent extrasystoles or atrial fibrillation, where oscillometric measurements are unreliable, and obesity with extremely large arm circumference and/or conical shaped arms, where fitting an appropriate cuff may be difficult. In the latter case the use of wrist devices for HBPM might possibly be justified, whereas otherwise upper arm devices should always be preferred.6The above advantages, together with the ability of HBPM and ABPM to provide a much larger number of values than office BP measurements, result in more stable estimates of the prevailing BP in a given subject, reflecting the actual BP burden on cardiac and vascular targets more precisely than office readings. This has not only methodological but also clinical relevance, as documented by a number of studies showing the prognostic superiority of HBPM or ABPM over isolated office BP measurements (Table 2).6–10,34 These observations are further reinforced by the demonstration that a worse prognosis characterizes subjects with normal office and elevated out-of-office BP, assessed by either HBPM or ABPM (masked hypertension), than subjects with normal out-of-office but elevated office BP (white coat or isolated office hypertension; Figure 1).9,18,30,35Download figureDownload PowerPointFigure 1. Adjusted hazard ratios and 95% CIs for the incidence of cardiovascular events in sustained hypertensive patients, masked hypertensive patients, and patients with isolated clinic hypertension vs true normotensive subjects. Data from 7 studies, including 11 502 subjects (Reference,35 by permission).Differences Between ABPM and HBPMNotwithstanding the above similarities, there are major differences between HBPM and ABPM that importantly influence their possible clinical and research applications. One of the key issues is the economic aspect of using either HBPM or ABPM. Although the price of validated ABPM devices has fallen considerably over the last years, making them more easily and widely available, still, the costs of the system and its maintenance remain relatively high, unquestionably higher than those of HBPM.6 This is of particular relevance when promoting BP monitoring in low-resource settings, where the prevalence of hypertension is increasing and the limited availability of economic resources does not allow costly equipment to be considered in a population setting.4 Thus, should HBPM and ABPM provide equivalent clinical information, the former technique would have to be preferred on the background of the possibility to reduce patients' management costs.36,37Admittedly, however, ABPM has a number of clinically relevant features that are not directly available with HBPM, which makes the former approach not easily replaceable by the latter. One of the peculiar advantages of ABPM lies in its ability to provide a series of frequent and automated BP measurements throughout the 24 hours, which makes ABPM, at variance from HBPM, capable to dynamically assess BP changes over relatively short periods of time. This might have clinical implications in light of the evidence supporting the adverse prognostic relevance of specific patterns of BP variability over 24 hours, including reduced nocturnal BP fall,38 increased short-term BP variability,39,40 and possibly also an excessive morning BP surge.41 Nevertheless, the actual clinical usefulness of assessing these dynamic BP features remains controversial because of the lack of universally accepted normal reference values for their interpretation, lack of well-defined interventions able to counteract their adverse effects, and missing evidence that their modification by treatment may significantly reduce cardiovascular risk. Thus, unless further studies provide clear solutions for the above-mentioned problems, the assessment of these ABPM-specific parameters will not be translated into stringent clinical recommendations and will remain mostly confined to a research setting.1 Moreover, it should be emphasized that information on dynamic BP changes may at least partly be supplied also by HBPM. It has been shown recently that the degree of day-by-day variability of home BP and HR values may have prognostic significance in predicting the risk of cardiovascular events (Figure 2),42,43 and some authors suggest that, in line with ABPM data, morning hypertension identified by HBPM might be a stronger predictor of cardiovascular events than an elevated evening BP.44 Obviously, the evidence supporting the use of HBPM in this context is by no means definitive, and it is not clear whether the information on BP changes provided by HBPM is comparable to that provided by ABPM. However, there are no doubts that HBPM represents a much more easily available source of information on BP variations than ABPM. Download figureDownload PowerPointFigure 2. Absolute 10-year risk of cardiovascular mortality in relation to SD of systolic BP and SD of heart rate obtained with HBPM (Reference,43 by permission).Undoubtedly, a clinically important feature of ABPM consists in its ability to assess the capacity of a given antihypertensive treatment to adequately control BP throughout the 24 hours in a hypertensive subject and to provide indications on the possible need to differentiate dosing times of different drugs. In particular, ABPM allows BP to be assessed at times when HBPM cannot be used at all (eg, at night) or only with major difficulties (eg, at work, early in the morning, or during different activities). The assessment of nocturnal BP control is indeed of major clinical relevance because of its demonstrated prognostic value.45 Although HBPM is in general less effective than ABPM in assessing the time distribution of BP control by treatment, it may still be sufficient in many cases, however. HBPM performed in the morning (before drug intake) and in the evening may be quite informative about the efficacy of therapeutic coverage over 24 hours and may identify cases of morning hypertension attributed to insufficient duration of action of prescribed antihypertensive medications. In fact, whereas duration of antihypertensive effect is usually assessed with ABPM and typically quantified through trough:peak ratio, an HBPM-derived index, known as the morning:evening ratio, was proposed as an alternative approach, although its validity has not been sufficiently documented so far.46 The above examples demonstrate that HBPM application has been proposed even in areas where ABPM was traditionally considered to be the only available solution.An important field of ABPM application is in clinical pharmacology, when investigating the size and distribution over 24 hours of the effects of newly developed antihypertensive agents. At the moment, ABPM remains the most frequently used tool in such a research setting because of its documented superiority over office BP. However, the use of HBPM is an alternative solution increasingly gaining importance in research on antihypertensive therapies, especially in studies where large populations are being studied and where a compromise between the precision of BP assessment and the cost of wide application of BP monitoring has to be reached.6,47On top of this, HBPM has a number of features not available with ABPM, which are currently boosting its increasing use in clinical practice. First, it allows BP monitoring to be performed repeatedly and regularly over extended periods of time, which is crucial to optimize BP control in treated patients and is not easily achievable with ABPM. In addition, HBPM encourages the patient's active involvement in the management of his or her high BP condition, thus improving compliance with treatment48; it may reduce the need to frequently attend medical checkups36; it favors a faster optimization of treatment regimens36,37,48,49; and, because of all of the above, it may by itself contribute to BP lowering.50 An important and frequently overlooked practical aspect is that a substantial proportion of patients do not tolerate repeated ABPM recordings, whereas HBPM is usually welcome by them. Furthermore, technological progress provides new functionalities of HBPM devices, which make them increasingly interesting for both clinicians and patients. These include drug intake reminders; internal memory facilities for easy storage and review of measured BP values; possibility of data printout or download to a computer; built-in programs for structured measurement schedules with automatic calculation of average daily and weekly values; and, finally, teletransmission of BP data to a remote centralized server.51 The last possibility allows the incorporation of HBPM in telemonitoring systems, further contributing to an improvement in hypertension control (Figure 3).52Download figureDownload PowerPointFigure 3. Percentage of patients with daytime ambulatory BP normalization (systolic BP <130 mmHg and diastolic BP <80 mmHg). In this study, hypertensive patients were randomized to conventional management with office BP measurement (□, n=111) or to teletransmission of home BP values (, n=187; Reference,53 by permission).Conclusions and Perspectives for the FutureThe current position is that HBPM and ABPM should coexist and be used as complementary tools, providing different information on a subject's BP status.6,7 However, HBPM may be a valid alternative to ABPM in many cases, possibly even in settings where ABPM is currently considered the method of choice, eg, identification of isolated office hypertension and of masked hypertension, clinical evaluation of BP variability, and assessment of antihypertensive drug coverage. In fact, in clinical practice, HBPM is increasingly replacing ABPM, with use of the former being recommended in all treated hypertensive subjects by recent guidelines,6,53 a recommendation that cannot apply to ABPM. This is because HBPM is an ideal first-line tool because of its low cost, high availability, and easy application. It may also be the most reasonable option for the initial assessment of untreated subjects, in whom white coat or masked hypertension is suspected, ie, those with highly variable office BP, with office BP close to diagnostic thresholds, with isolated out-of-office BP values discrepant from office BP, with evidence of organ damage contrasting with office BP findings, etc. Moreover, HBPM is clearly the tool of choice in monitoring BP control in treated subjects over extended periods of time, also because it has the particular advantage of promoting a better therapeutic adherence.48 Possible exceptions are cases where recommendation of HBPM use to a patient ends up in obsessively frequent self-BP measurements, or, even worse, in self-modification of treatment on the basis of isolated and ill-interpreted BP findings. Still, in many such cases, an appropriate interaction between patient and physician, including patient education, may be sufficient to overcome this kind of problem so that only in a few cases should HBPM be discouraged and ABPM used instead. Finally, whereas ABPM remains the leading method in research on antihypertensive therapies, in outcome trials carried out in large populations, where the effects of BP lowering are assessed over many months or years, HBPM may be an interesting alternative solution.Therefore, we believe that priority should be given to HBPM in most patients when out-of-office BP assessment is needed. Possible exceptions, where ABPM should definitely be used, include high-risk patients with severe, difficult-to-control hypertension, in whom an adequate 24-hour BP control is crucial, and patients where the assessment of short-term BP variability and of the behavior of nocturnal BP is specifically indicated. ABPM might be also used as a second choice whenever HBPM does not provide clear answers to diagnostic questions, ie, when HBPM values are borderline or when it is likely that they have been influenced by methodological factors, as in the case of inappropriate use by patients with cognitive impairment or inaccurate BP data reporting. According to such an approach, out-of-office BP measurement would be available to a wide range of subjects with relatively modest costs, leaving the more expensive ABPM to selected cases only.In summary, both HBPM and ABPM are extremely useful in hypertension management, with a partial overlap of their clinical indications. Given that the clinical information they provide is not identical, both of these methods are likely to remain in use by physicians in daily practice. However, because of the important scientific and technological progress taking place in the field of HBPM, it may be expected that the number of HBPM applications and indications will be increasing, making this approach often preferable to ABPM. More studies are still needed, though, to define situations where the information provided by HBPM is sufficient for clinically successful and cost-effective hypertension management, including prognostic stratification of hypertensive patients. Finally, we cannot exclude that progress in technology might soon lead to the development of inexpensive, automated BP measuring devices combining the functionalities and advantages of ABPM and HBPM tools (eg, HBPM devices with the capacity of automatically obtaining nighttime and/or ambulatory measurements), thus providing a practical solution to the current debate on the choice between these 2 approaches.DisclosuresG.P. has received lecture honoraria from Omron Healthcare and Microlife; G.B. has received lecture honoraria from Docleader Srl; S.O. has received lecture honorarium from Omron Healthcare.FootnotesCorrespondence to Gianfranco Parati, Department of Cardiology, Ospedale San Luca, Istituto Auxologico Italiano, via Spagnoletto 3, 20149 Milan, Italy. E-mail [email protected] References 1 Mancia G, De Backer G, Dominiczak A, Cifkova R, Fagard R, Germano G, Grassi G, Heagerty AM, Kjeldsen SE, Laurent S, Narkiewicz K, Ruilope L, Rynkiewicz A, Schmieder RE, Boudier HA, Zanchetti A, Vahanian A, Camm J, De Caterina R, Dean V, Dickstein K, Filippatos G, Funck-Brentano C, Hellemans I, Kristensen SD, McGregor K, Sechtem U, Silber S, Tendera M, Widimsky P, Zamorano JL, Erdine S, Kiowski W, Agabiti-Rosei E, Ambrosioni E, Lindholm LH, Viigimaa M, Adamopoulos S, Agabiti-Rosei E, Ambrosioni E, Bertomeu V, Clement D, Erdine S, Farsang C, Gaita D, Lip G, Mallion JM, Manolis AJ, Nilsson PM, O'Brien E, Ponikowski P, Redon J, Ruschitzka F, Tamargo J, van Zwieten P, Waeber B, Williams B. Management of Arterial Hypertension of the European Society of Hypertension; European Society of Cardiology. 2007 Guidelines for the Management of Arterial Hypertension: the Task Force for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC). J Hypertens. 2007; 25: 1105–1187.CrossrefMedlineGoogle Scholar2 Chobanian AV, Bakris GL, Black HR, Cushman WC, Green LA, Izzo JL Jr, Jones DW, Materson BJ, Oparil S, Wright JT Jr, Roccella EJ; National Heart, Lung, and Blood Institute Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure; National High Blood Pressure Education Program Coordinating Committee. The seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: the JNC 7 report. Hypertension. 2003; 42: 1206–1252.LinkGoogle Scholar3 Parati G, Valentini M. Do we need out-of-office blood pressure in every patient? Curr Opin Cardiol. 2007; 22: 321–328.CrossrefMedlineGoogle Scholar4 Parati G, Mendis S, Abegunde D, Asmar R, Mieke S, Murray A, Shengelia B, Steenvoorden G, Van Montfrans G, O'Brien E. World Health Organization Recommendations for blood pressure measuring devices for office/clinic use in low resource settings. Blood Press Monit. 2005; 10: 3–10.CrossrefMedlineGoogle Scholar5 Stergiou GS, Baibas NM, Gantzarou AP, Skeva II, Kalkana CB, Roussias LG, Mountokalakis TD. Reproducibility of home, ambulatory, and clinic blood pressure: implications for the design of trials for the assessment of antihypertensive drug efficacy. Am J Hypertens. 2002; 15: 101–104.CrossrefMedlineGoogle Scholar6 Parati G, Stergiou GS, Asmar R, Bilo G, de Leeuw P, Imai Y, Kario K, Lurbe E, Manolis A, Mengden T, O'Brien E, Ohkubo T, Padfield P, Palatini P, Pickering T, Redon J, Revera M, Ruilope LM, Shennan A, Staessen JA, Tisler A, Waeber B, Zanchetti A, Mancia G; ESH Working Group on Blood Pressure Monitoring. European Society of Hypertension guidelines for blood pressure monitoring at home: a summary report of the Second International Consensus Conference on Home Blood Pressure Monitoring. J Hypertens. 2008; 26: 1505–1526.CrossrefMedlineGoogle Scholar7 Pickering TG, Miller NH, Ogedegbe G, Krakoff LR, Artinian NT, Goff D; American Heart Association; American Society of Hypertension; Preventive Cardiovascular Nurses Association. Call to action on use and reimbursement for home blood pressure monitoring: executive summary: a joint scientific statement from the American Heart Association, American Society Of Hypertension, and Preventive Cardiovascular Nurses Association. Hypertension. 2008; 52: 1–9.LinkGoogle Scholar8 Ohkubo T, Imai Y, Tsuji I, Nagai K, Kato J, Kikuchi N, Nishiyama A, Aihara A, Sekino M, Kikuya M, Ito S, Satoh H, Hisamichi S. Home blood pressure measurement has a stronger predictive power for mortality than does screening blood pressure measurement: a population-based observation in Ohasama. Japan J Hypertens. 1998; 16: 971–975.CrossrefMedlineGoogle Scholar9 Mancia G, Facchetti R, Bombelli M, Grassi G, Sega R. Long-term risk of mortality associated with selective and combined elevation in office, home, and ambulatory blood pressure. Hypertension. 2006; 47: 846–853.LinkGoogle Scholar10 Sega R, Facchetti R, Bombelli M, Cesana G, Corrao G, Grassi G, Mancia G. Prognostic value of ambulatory and home blood pressures compared with office blood pressure in the general population: follow-up results from the Pressioni Arteriose Monitorate e Loro Associazioni (PAMELA) Study. Circulation. 2005; 111: 1777–1783.LinkGoogle Scholar11 Hozawa A, Ohkubo T, Nagai K, Kikuya M, Matsubara M, Tsuji I, Ito S, Satoh H, Hisamichi S, Imai Y. Prognosis of isolated systolic and isolated diastolic hypertension as assessed by self-measurement of blood pressure at home: the Ohasama Study. Arch Intern Med. 2000; 160: 3301–3306.CrossrefMedlineGoogle Scholar12 Ohkubo T, Asayama K, Kikuya M, Metoki H, Hoshi H, Hashimoto J, Totsune K, Satoh H, Imai Y. Ohasama Study. How many times should blood pressure be measured at home for better prediction of stroke risk? Ten-year follow-up results from the Ohasama study. J Hypertens. 2004; 22: 1099–1104.CrossrefMedlineGoogle Scholar13 Asayama K, Ohkubo T, Kikuya M, Metoki H, Obara T, Hoshi H, Hashimoto J, Totsune K, Satoh H, Imai Y. Use of 2003 European Society of Hypertension-European Society of Cardiology guidelines for predicting stroke using self-measured blood pressure at home: the Ohasama Study. Eur Heart J. 2005; 26: 2026–2031.CrossrefMedlineGoogle Scholar14 Ohkubo T, Asayama K, Kikuya M, Metoki H, Obara T, Saito S, Hoshi H, Hashimoto J, Totsune K, Satoh H, Imai Y. Prediction of ischaemic and haemorrhagic stroke by self-measured blood pressure at home: the Ohasama study. Blood Press Monit. 2004; 9: 315–320.CrossrefMedlineGoogle Scholar15 Asayama K, Ohkubo T, Kikuya M, Metoki H, Hoshi H, Hashimoto J, Totsune K, Satoh H, Imai Y. Prediction of stroke by self-measurement of blood pressure at home versus casual screening blood pressure measurement in relation to the Joint National Committee 7 classification: the Ohasama Study. Stroke. 2004; 35: 2356–2361.LinkGoogle Scholar16 Nishinaga M, Takata J, Okumiya K, Matsubayashi K, Ozawa T, Doi Y. High morning home blood pressure is associated with a loss of functional independence in the community-dwelling elderly aged 75 years or older. Hypertens Res. 2005; 28: 657–663.CrossrefMedlineGoogle Scholar17 Okumiya K, Matsubayashi K, Wada T, Fujisawa M, Osaki Y, Doi Y, Yasuda N, Ozawa T. A U-shaped association between home systolic blood pressure and fouryear mortality in community-dwelling older men. J Am Geriatr Soc. 1999; 47: 1415–1421.CrossrefMedlineGoogle Scholar18 Bobrie G, Chatellier G, Genes N, Clerson P, Vaur L, Vaisse B, Menard J, Mallion JM. Cardiovascular prognosis of 'masked hypertension' detected by blood pressure self-measurement in elderly treated hypertensive patients. JAMA. 2004; 291: 1342–1349.CrossrefMedlineGoogle Scholar19 Agarwal R, Andersen MJ. Prognostic importance of clinic and home blood pressure recordings in patients with chronic kidney disease. Kidney Int. 2006; 69: 406–411.CrossrefMedlineGoogle Scholar20 Fagard RH, Van Den BC, De Cort P. Prognostic significance of blood pressure measured in the office, at home and during ambulatory monitoring in older patients in general practice. J Hum Hypertens. 2005; 19: 801–807.CrossrefMedlineGoogle Scholar21 Stergiou GS, Baibas NM, Kalogeropoulos PG. Cardiovascular risk prediction based on home blood pressure measurem