Early to Rise: A.M. Hypertension and Home BP Monitoring

Robert Lee Page II, PharmD, BCPS, FASCP, FSGC, CGP;

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Early to Rise: A.M. Hypertension and Home BP Monitoring

May 1, 2007

Robert Lee Page II, PharmD, BCPS, FASCP, FSGC, CGP

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Pharmacy Times

Volume 0

Behavioral Objectives

After completing this continuing education article, the pharmacist should be able to:

1. Delineate the specific type of hypertension (eg, morning,masked, or white-coat hypertension) a patient may beexperiencing.

2. Explain the neurohormonal imbalances as well as thepossible dangers associated with morning hypertension.

3. Describe the pathophysiology behind the circadianrhythm of the body, particularly as it impacts the cardiovascularsystem.

4. Counsel a patient on appropriate blood pressure deviceselection, technique, and validation.

5. Communicate the clinical importance of monitoringblood pressure at home.

Recently, home blood pressure(HBP) monitoring has become anacceptable and popular methodfor the diagnosis and assessment ofhypertension. As technology regardingthese devices has advanced, so has theamount of published data documentingits clinical value. Currently, more than 10million HBP devices are produced annuallyworldwide. Compared with blood pressure(BP) measurements obtained in anoffice or clinic, HBP monitoring offersgreater patient convenience, more accurateand reproducible BP readings, betterprognostic value, and patient-centeredinvolvement, which in turn enhancesdrug-therapy adherence.^1-3

HBP can also assist in the detection ofvarious types of hypertension, such aswhite-coat, masked, and morning hypertension.In the case of morning hypertension,the "surge"type has been independentlyassociated with elevated cardiovascularrisks and can be deadly if notrecognized and appropriately managed.^1-3Uncontrolled hypertension results innumerous deaths among Americans, andit is a serious risk factor for other deadlycardiovascular diseases; thus, the pharmacistis ideally positioned to assist withdiagnosis and management of this publichealth concern. This continuing educationlesson will explain the concepts of circadianrhythm of BP; the various types ofmorning hypertension; the dangers associatedwith morning hypertension, specificallythe morning surge type; the clinicalbenefits that HBP monitoring can offerpatients; and the pharmacist's role inappropriate HBP device selection.

Review of Chronobiology

A master clock resides deep within theanterior hypothalamus of the brain of allmammals, known as the suprachiasmaticnucleus.⁴This nucleus is made up of positiveand negative transcriptional andtranslational feedback loops that drivegene expression. This master clock isbelieved to ultimately oversee the coordinationof biological and physiologicprocesses within a predictable-in-timecyclic variability also known as circadianrhythm. Over time, light/dark and othersocietal/environmental time cues trainour master clock to a 24-hour time structureand stage the peaks and troughs ofcircadian rhythms to support the diurnalactivity-nocturnal sleep routine. By communicatingwith other peripheral clockslocated in tissues of the heart, liver, kidneys, and adrenal glands, the masterclock modulates individual rhythms inthe periphery via hormones or hemodynamiccues. The study of these circadianrhythms and how they impact physiology,disease, and outcomes is known aschronobiology. Data have suggested thathuman biochemistry and physiology arenot constant, but rather vary in a predictablemanner during the 24-hour timeperiod.^5-10

The sleep cycle is a prime example ofbiochemical and physiologic rhythms:just prior to sleep, basal gastric acidsecretion, white blood cell count, andatrial natriuretic peptides (which arepotent vasodilators) start to rise. As thesleep cycle progresses, growth and thyroid-stimulating hormone, blood lymphocyteand eosinophil number, and plasmaconcentrations of melatonin and prolactinalso begin to peak, as do adrenocorticotropichormone, follicle-stimulatinghormone, and luteinizing hormone.By the early morning hours, plasma cortisol,renin, angiotensin, and aldosteronecrest, leading to an increase in arterialcompliance, vascular resistance, plateletaggregation, and blood viscosity. By theafternoon, hemoglobin and insulin concentrationsare at their highest levels,whereas serum cholesterol and triglyceridesare at maximum concentration inearly evening.^5,6,10,11

Circadian Rhythm of BloodPressure

Cardiovascular hemodynamics alsofollows a circadian pattern. Heart rate(HR) and BP are the lowest during sleepand rise toward the end of the sleepcycle.^12-14On awakening, a change in postureis followed by systemic increases incatecholamines, cortisol, aldosterone,angiotensin, and renin, which accompanyphysical and psychological stress.^15,16Moreover, the body exhibits heightenedsensitivity to such changes, as evidencedby the lower concentration of epinephrineneeded to induce platelet aggregationor vessel vasoconstriction. All ofthese actions translate to increased HR,BP, coronary tone, and vessel caliber.^5,13

Morning Hypertension

Definitions

Due to these neurohormonal changes,the typical circadian variation in BP forthe majority of patients with hypertensionincludes a nadir that occurs duringthe nighttime hours and a surge thatoccurs during the early-morning periodwhen people typically arise for the day.This is referred to as morning hypertension.Although not validated, morninghypertension has been defined as amorning BP exceeding 135/85 mm Hg.Morning hypertension is classified accordingto 2 types (Figure 1). Patients whodemonstrate persistently high BP fromnighttime to morning are referred to as"nondippers,"because their BP remainselevated all night. This type of morninghypertension is also called sustained ornocturnal hypertension. Sustained hypertensionoccurs in about 10% to 30% ofpatients with hypertension and is associatedwith a high risk of target-organ(brain, kidney, heart) damage and cardiovascularevents.¹⁷Morning surge hypertension(MSH) is the second type and ischaracterized by extreme dips of nocturnalBP. For these 10% to 20% of patientsalso known as "extreme dippers,"nighttimeBP is >20% lower than daytime BP.In healthy individuals, this morning BPsurge is just 1 of the components of thediurnal variation in BP and is associatedwith morning stress on rising, which normalizeswithin a few hours of awaking.For the MSH patient, however, thisexcessive, sudden elevation in BP can bedeadly and is an independent risk factorfor cardiovascular disease, particularly inolder adults who may have impairedautoregulation.

Pathogenesis of MSH

During the early-morning hours, manydifferent neurohormonal systems areactivated (Figure 2). With a change inposture, the sympathetic nervous system(SNS) becomes stimulated, causingthe release of epinephrine and norepinephrineinto the circulation. Just prior toawaking, the renin-angiotensin-aldosteronesystem (RAAS) is also stimulated,thereby increasing the production ofangiotensin II.^18,19As mentioned earlier, ina healthy individual, these processes aremerely physiologic adjustments to compensatefor the change from a horizontalto a vertical position and the consequentincrease in cardiovascular demand. Inthe patient with hypertension, however,these systems are dysregulated. Forexample, in patients with MSH, theincrease in angiotensin II can be on theorder of 200% of normal. Such a largeabrupt elevation brings about vascularinflammation, endothelial damage, andvasoconstriction.²⁰When accompaniedby heightened platelet activity andgreater blood viscosity, these actionstranslate to increased HR and systemicvascular resistance, which disrupt theequilibrium between myocardial oxygendemand and supply.

Pathophysiologic processes associated with MSH can also result in rupture ofvulnerable atherosclerotic plaques.Atherosclerotic plaques start to emergeas early as the teenage years. Becausethese plaques are asymptomatic, mostpeople have no concept of what may bebuilding within their vasculature until it istoo late. With an increase in arterial pressureand vasoconstriction brought on bythe SNS and RAAS, shear stress cancause an initial disruption of an atheroscleroticplaque, which initiates a cascadeof inflammatory processes. Onceintimal collagen is exposed, plateletaggregation and inflammatory mediatorscause thrombus formation around thedisrupted plaque. Macrophages releaseproteases, which further degrade thethin fibrous cap surrounding the plaque'slipid core, resulting in full-blown rupture.Minor ruptures can lead to asymptomaticmural thrombus characterized byunstable angina or non-ST-segment-elevationmyocardial infarction (MI). A majorrupture can culminate in a potentiallyfatal occlusive coronary thrombus withthe addition of other external stimuli(such as an early-morning cigarette, coldweather, Monday-morning stress) to theincreased coagulability and vasoconstriction.^14,21-23

With this in mind, it seems plausiblethat timing of certain life-threateningemergencies may parallel these physiochemicalcircadian variations, especiallyin patients with underlying cardiovasculardisease. This hypothesis has been validatedby large database analyses, andepidemiologic studies have found theincidence of cardiovascular events (eg,MI, sudden cardiac death, thromboticstroke, and angina) occur several-foldmore frequently during the early-morninghours (ie, 6 AM-12 PM), compared withany other time of the day or night.^24,25Data from the JICHI Morning HypertensionResearch study (J-MORE) suggestthat, even in medicated patients withhypertension, the presence of older age(=65 years), regular alcohol consumption,and smoking may increase surges inmorning BP.^26-28Other risk factors associatedwith MSH include metabolic syndrome,renal disease, and diabetes.^29,30Aswith many chronic diseases, MSH maybe genetically linked. Curtis and colleagueshave identified various genes(Bmal1^-/-, Clock^mut, and Npas2^mut) from themaster clock in the brain that play a rolein the regulation of enzymes relevant tothe synthesis and disposition of catecholamines,resulting in alterations innorepinephrine and epinephrine throughoutthe day, as well as changes in thesevariables in response to stress.³¹Although the clinical onset of vascularevents occurs more frequently in themorning, it is unknown whether thisincrease is the result of this "molecular"master clock or merely the physical andemotional stress of getting up andbecoming active after slumber.

Effects on Cardiovascular Events

The effects of MSH on target organscan be devastating, particularly in vulnerablepopulations such as patients withdiabetes and the elderly. In type 2 diabetes,MSH is strongly related to bothmicrovascular and macrovascular complications,especially nephropathy, comparedwith other patients with hypertensionand diabetes. Other investigatorshave determined that MSH at themoment of rising is more strongly relatedto organ damage as measured by thepresence of cardiac hypertrophy andalbuminuria independent of other BPmeasurements, especially in olderadults.³²

In a subanalysis of the Ohasama study,1766 patients with hypertension wereassigned to 1 of 4 categories based onhome BP values: normotensive (bothmorning and evening BP <135/80 mmHg); MSH (morning BP =135/85 mm Hgand evening BP <135/85 mm Hg);evening hypertensive (morning BP<135/85 mm Hg and evening BP >135/85mm Hg); and sustained hypertensive(both morning and evening BP =135/85mm Hg).³³Compared with normotensivepatients, the investigators found thatpatients with morning surge and sustainedhypertension had a 2.66 and 2.38times higher risk of a stroke, respectively(P < .0001). In fact, for patients with MSHcurrently receiving antihypertensivetherapy, the stroke risk was even higher(risk hazard, 3.55, P < .0001).

Kario and colleagues prospectivelyevaluated stroke prognosis in 519 olderpatients with hypertension in whichambulatory BP monitoring was performed.^34,35The morning BP surge wasdefined as the difference between themean systolic BP during the 2 hours afterwaking and arising minus the mean systolicBP duringthe hour that includedthe lowestBP duringsleep. Over the41-month studyperiod, 44 strokesoccurred. Patientswere divided into2 groups: morningsurge (=55mm Hg) and nonmorningsurge(<55 mm Hg).

The investigators found that those in themorning-surge group had a higher baselineprevalence of multiple cerebralinfarcts (57% vs 33%, P = .001) and ahigher incidence of stroke (19% vs 7.3%,P = .004), compared with the non-morning-surge group, respectively. Moreover,the morning surge was associated withstroke events independent of 24-hour BP,nocturnal BP dipping status, and baselineprevalence of silent infarcts (P = .008).

MSH also has been correlated with leftventricular hypertrophy (LVH).³⁶If leftuntreated, LVH can ultimately lead to thedevelopment of heart failure, ventriculararrhythmias, atrial fibrillation, and evensudden death.

Ikeda and colleagues evaluated 297patients with hypertension who weretreated with amlodipine for at least 1year. Patients were divided into 2 groups:MSH (morning BP =135/85 mm Hg andevening BP <135/85 mm Hg) and eveninghypertension (morning BP <135/85 mmHg and evening BP >135/85 mm Hg). At 3months, all patients received echocardiography.

Compared with a control group,those in the MSH group had a significantlygreater left ventricular massindex (P = .001). After a multivariateregression analysis was conducted,morning rise in BP was the dominantpredictor of LVH.

The totality of the evidence surroundingthe association between target-organdamage and MSH logically suggests thatHBP should be incorporated into the diagnosisand assessment of hypertension.

Overview of HBP Monitoring

Initially, HBP measurements weredone using the auscultation method witheither mercury sphygmomanometers oraneroid manometers, as typically used inphysician offices. For the patient, however,these devices are difficult to use andrequire extensive training and skill. Theautomated cuff-oscillometric devices,which record pressure from the brachialartery, have become popular due to easeof use and the incorporation of digitalreadout and computer memory. Presently,several organizations have guidelinesaddressing established proceduresfor HBP measuring; these include theInternational Consensus Conference ofSelf BP Monitoring (ICCSBM), theAmerican Heart Association (AHA) recommendationsfor BP measurement, theEuropean Society of Hypertension recommendationsfor BP measurement,and the Japan Society of Hypertension(JSH) guidelines for self-monitoring of BPat home.^1,37-40

Indications and Contraindications

The American Society of Hypertension(ASH) recommends the use of HBP monitoringfor the majority of patients withhypertension, pointing to 4 potential benefits:

?Differentiating sustained from whitecoathypertension?Assessing the response to antihypertensivetherapy?Improving compliance?Reducing costs⁴¹

Very little has been written regardingcontraindications. Studies have suggestedthat patients with a low educationlevel often report inaccurate HBP readings.⁴²Those with severe mental or physicaldisabilities may also not be appropriatecandidates for HBP monitoring.Irregularity of the pulse may render theresults less accurate, so atrial fibrillationmay be a contraindication.⁴³

Types of Monitors

Three different categories of cuff-oscillometricdevices exist: the upper-armcuff, the wrist cuff, and the finger cuff.The finger-cuff device is not recommendeddue to measurement inaccuraciesrelated to vasoconstriction, alteration inBP the more distal the site of the recording,and limb positioning. Traditionalwrist-cuff devices are subject to thesame problems as the finger cuff in additionto problems with changing the positionof the wrist. However, certain wristBP monitors with positioning technologythat only allow them to inflate when theyare at heart level have been proven accuratein recently published clinical studiesamong adults, obese adults, and the elderly.Currently, the upper-arm cuff devicehas been shown to be most reliable.

Validation of Individual Monitors

The home BP monitor market ispresently flooded, with a multitude ofmanufacturers offering closely competitiveproducts. These products continueto evolve with respect to their complexity,variety of functions, and cost. Accuracyshould be the primary goal fordevice selection. Only monitors that havebeen subjected to proper validation testsshould be used in clinical practice. Theoriginal 2 protocols with the widestacceptance were developed by theAssociation for the Advancement ofMedical Instrumentation in 1987, revisedin 2002, and the British HypertensionSociety in 1990, revised in 1993.^44,45Unfortunately, only a few oscillometricdevices have been subject to these tests.

An up-to-date list of validated monitorsis available at www.dableducational.com/accuracy_criteria.html or www.bhsoc.org/blood_pressure_list.st. The Tableprovides a list of selected, validatedupper-arm devices for self-measurement.^46,47

The fact that a monitor has passed avalidation test does not always ensure100% accuracy in individual patients. Thisis particularly concerning for older adultsand patients with diabetes. In thesepatients, error with a device can be ashigh as 5 mm Hg. For this reason, allpatients should validate their device onthemselves before recording BP readings.No formal protocol has been developedfor doing this, but 2 methods havebeen suggested: the sequential methodand the simultaneous method. With thesequential method, the automated-cuffoscillometricdevicereadings arecompared withthe alternatingreadings of a traditionalmercurysphygmomanometeron the samearm. With the simultaneousmethod,the readings fromsimultaneous measurementsarecompared. First,the automated deviceis used onone side and the sphygmomanometeron the other side. Next, each measurementis done using the contralateral arm.Regardless of the method used, at least 2measurements by both automated deviceand mercury sphygmomanometerare recommended, and the deviceshould be validated if both readingstaken are within at least 5 mm Hg ofeach other. Monitors should be checkedfor accuracy every 1 to 2 years.^1,37-40

It is further recommended that deviceswith memory or those that can downloaddata to a personal computer areused, as some patients may have poorreporting accuracy. In 2 studies, >50% ofpatients who used HBP monitors eitheromitted or fabricated their readings.^1,37-40

User Procedure

As with office BP measurements, HBPmeasurements should be performedunder controlled conditions with the procedureof measurement standardized, asmentioned early. The ASH and JSH recommendthat 1 or 2 home BP measurementsbe obtained in the morning andevening. In the JSH guidelines, morning isdefined as 1 hour after arising fromsleep, after micturition, before breakfast,and before taking medications; whereasevening suggests just prior to bedtime.On all occasions, HBP should be taken inthe same position after a period of a fewminutes. The AHA recommends 3 to 5minutes of rest before measurement.¹

The number of HBP measurements oneach occasion remains a matter ofdebate. The guidelines of the ICCSBMsuggest 2 consecutive measurements inthe morning and evening. The AHA recommendsthat 2 or 3 readings be takenin succession, separated by =1 minutes,whereas the JSH guidelines suggest atleast 1 measurement on each occasion.^1,39Kario and colleagues haveassessed the association between thenumber of measurements and the levelof hypertensive organ damage, brainnatriuretic peptide (BNP), and urinaryalbumin excretion (UAE). In this study,second or third readings demonstratedsignificantly higher correlation with bothBNP and UAE than first readings.⁴⁸In astudy of 1491 patients with hypertension,Ohkubo and colleagues evaluatedthe optimum number of BP self-measurementsin relation to the predictivevalue for stroke risk. The investigatorsfound that no actual threshold existedfor the number of HBP measurementswithin the range of 1 to 14 measurements,suggesting that "as many as possible"measurements should be obtainedfor better prediction of stroke risk.⁴⁹Based on the present evidence, HBPmeasurements should be performedmultiple times and all values recordedwithout selection.

Home BP Readings

What is considered a normal HBPreading? HBP readings are typicallylower than clinical BP readings in mostpatients. In population surveys, the differenceis shown to be approximately 10/5mm Hg. Several studies have assessed atwhat level the home pressure correspondsto a normal clinic pressure of140/90 mm Hg. The largest trial to date,the Ohasama study, has suggested anupper limit of normal to be 137/84 mmHg.^3,50The Ohasama investigators foundthat, above this level of BP, a significantincrease in cardiovascular risk wasestablished. After reviewing the currentavailable published evidence, an ad hoccommittee of the ASH has suggested135/85 mm Hg as an acceptable upperlimit of normal.⁵¹This BP limit is also recommendedby the AHA.¹Although a normalBP threshold for home monitoringhas been suggested, the treatment goalfor HBP values has never been trulyestablished. Additional large-scale studieswill be needed to establish this BPrange. As with office-based BP readings,the AHA also suggests that a lower HBPgoal be recommended for certain patientpopulations: patients with diabetes, pregnantwomen, and patients with renal failure.Unfortunately, no specific goals havebeen defined specifically for HBP monitoring.¹

Prognostic Value of HBP Monitoring

For many years, office BP has beenused as the gold standard for clinical BPmeasurement. In the past 5 years, however,the value of HBP monitoring in combinationwith office measurements hasbeen documented.

Widespread adoption of self-monitoringBP in clinical practice has been slowdue to lack of prognostic data. Twoprospective studies have found that HBPmonitoring better predicts morbidevents, compared with conventionaloffice measurements. The Ohasamastudy was a prospective study evaluatingthe relation between initial BP levels(home and clinic) and subsequent allcausemortality in a cohort of 1789 ruralJapanese. The mean duration of followupwas 6.6 years. The investigators foundthat HBP was more strongly predictive oflater mortality than clinical BP. Analyzingboth systolic and diastolic levels of clinicalBP, initial (first 2 readings) HBP, andmultiple (>3 readings, mean number 20)HBP measurements, only the mean multiplehome systolic BP was significantlycorrelated with subsequent mortality.³

In the Self-Measurement of BloodPressure at Home in the Elderly study,4939 patients with hypertension aged 60years or older were followed for a meanof 3.2 years and evaluated for cardiovascularmortality based on their method ofBP measurements (ie, HBP or office monitoring).²The investigators found thatinclusion of HBP self-measurements betterdefined the prognosis of cardiovascularmorbidity and mortality, comparedwith office visits alone. For example, 9%of patients with well-controlled hypertensionat home, but poorly controlledhypertension in the physician's office,also known as white-coat hypertension,were detected and appropriately diagnosed.The authors also noted that, in avery small subset of patients, HBP monitoringdetected the phenomenon knownas reverse white-coat syndrome, ormasked hypertension. In this case, BPreadings are normal in the provider'soffice but abnormal at home. These findingshave also been validated by otherlarge cross-sectional studies.^52-54

Furthermore, increasing evidenceshows that HBP also better predictshypertensive organ damage more closelythan clinical BP measurements.^55-57Mule and colleagues evaluated 38patients with hypertension by clinical,ambulatory, and HBP measurements.Each patient recorded HBP for 2 dayswith a digital BP monitor 3 times daily,the first time on the same day duringwhich ambulatory monitoring was simultaneouslyperformed. They concludedthat HBP measurements, especiallythose recorded on the second day, correlatedsignificantly, and more tightly thanclinical BP, with LVH, renal function, andglobal target-organ damage.⁵⁵

HBP and Compliancewith Medication Therapy

Several studies have indicated thatHBP monitoring not only is effective atincreasing patient drug adherence butmay lead to betterBP control.^58-60In some situations,self-monitoringincreasedmedication adherencefrom 0% to70%.^58,59An HBPmonitor providesa visual reminderand a positivereinforcement toolfor drug adherence.Self-monitoringcan also help to determine correctdrug-dose intervals while patients areawake and to assess the efficacy oftherapeutic modifications. This in turnreinforces the advantages of maintainingBP within specified goals, possibly motivateslifestyle changes, and allows patientsa better overall understanding ofthe disease.

HBP and Limitations

Unfortunately, several limitationsexist with HBP monitoring. First, someHBP devices can be expensive and noteasily affordable for patients. Second,because of the lack of large studies, HBPmonitoring cannot be used to decidewhether treatment is indicated. Thetreatment decision must still be basedon repeated clinic BP readings. Onceestablished, the HBP reading can beused to exclude individuals who are atrisk for side effects due to low out-of-officeBP readings and to precisely monitorthe BP response to therapy. Third,goal HBP for special populations such asthose with renal disease or who arepregnant have not been clearly defined.Finally, accurate BP measurements areonly possible when patients have anexcellent understanding of the deviceand its correct use. Erroneous HBPreadings due to inappropriate deviceuse could potentially mislead a patientand a provider.

Implications for Pharmacists

Role of the Pharmacist

As pharmacists, it is important not onlyto identify appropriate patients who warrantHBP monitoring but also to assistpatients in identifying a monitor that issuitable to their needs. A patient shouldfeel content with all aspects of the monitor,including cost, user-friendliness,quality, and mobility of the unit. If unsatisfied,a patient might stop using thedevice.

A crucial aspect of self-monitoring isproperly fitting the BP cuff to the individualpatient. Unless fitted correctly, thedevice fails to maintain accuracy andpatient comfort during use. A cuff bladderthat is too narrow or too short producesa falsely elevated BP, and a bladderthat is too long or wide will underestimatethe actual value. The recommendedcuff sizes are as follows¹:

?For arm circumference of 22 to 26cm, the cuff should be "small adult"size: 12 22 cm?For arm circumference of 27 to 34cm, the cuff should be "adult"size:16 30 cm?For arm circumference of 35 to 44cm, the cuff should be "large adult"size: 16 36 cm?For arm circumference of 45 to 52cm, the cuff should be "adult thigh"size: 16 42 cm

Patient Counseling

After an HBP monitor has been selected,it is up to the pharmacist to communicateappropriate device use. High-qualityand accurate BP measurements arepossible only if patients use the devicecorrectly. Although the simplicity of digitalmonitors diminishes the potential forerrors, the pharmacist must explain tothe patient the specific instructionsincluded by the manufacturer anddemonstrate proper BP measuring technique.¹The following should be communicatedto the patient:

?The patient should be seated in acomfortable chair with the back fullysupported and the upper arm free ofconstrictive clothing?Both feet should be on the floor andlegs not crossed?The cuffed arm should be supportedand placed at the level of the heart,and the cuff should encircle at least80% of the arm circumference?The patient should not smoke, eat,exercise, or consume caffeine for=30 minutes prior to measuring BP?Measurements should be taken afterthe patient has remained quietlyseated for 3 to 5 minutes?The patient should not talk during themeasurement?Typically, 3 measurements should beobtained 1 minute apart in the morningon awakening and again prior tobedtime. Timing and frequency maybe patient-specific, however.?Patients should either store all HRand BP measurements in the memoryof the device or keep a carefullydocumented written record with thetime and date of measurements?The patient should always take thedevice and/or measurement to allhealth care provider visits?The patient should be encouraged tovalidate the device readings withoffice or clinical readings

Conclusions

The use of HBP monitoring continuesto gain popularity and acceptance byboth patients and providers as an essentialand vital comp

References

1. Pickering TG, Hall JE, Appel LJ, et al. Recommendations for blood pressuremeasurement in humans and experimental animals: Part 1: blood pressuremeasurement in humans: a statement for professionals from the Subcommittee ofProfessional and Public Education of the American Heart Association Council onHigh Blood Pressure Research. Hypertension. 2005;45(1):142-161.

2. Bobrie G, Chatellier G, Genes N, et al. Cardiovascular prognosis of "maskedhypertension" detected by blood pressure self-measurement in elderly treatedhypertensive patients. JAMA. 2004;291(11):1342-1349.

3. Ohkubo T, Imai Y, Tsuji I, et al. Home blood pressure measurement has astronger predictive power for mortality than does screening blood pressuremeasurement: a population-based observation in Ohasama, Japan. J Hypertens.1998;16(7):971-075.

4. Moore RY, Silver R. Suprachiasmatic nucleus organization. Chronobiol Int.1998;15(5):475-487.

5. Munger MA, Kenney JK. A chronobiologic approach to the pharmacotherapy ofhypertension and angina. Ann Pharmacother. 2000;34(11):1313-1319.

6. Reinberg A. Biological Rhythms and Medicine. New York, NY: Springer-Verlag;1983.

7. Rensing L, Meyer-Grahle U, Ruoff P. Biological timing and the clock metaphor:oscillatory and hourglass mechanisms. Chronobiol Int. 2001;18(3):329-369.

8. Smolensky MH. Chronobiology and chronotherapeutics: applications tocardiovascular medicine. Am J Hypertens. 1996;9(4 Pt 3):11S-21S.

9. Smolensky MH, D'Alonzo GE. Medical chronobiology: concepts andapplications. Am Rev Respir Dis. 1993;147(6 Pt 2):S2-S19.

10. Smolensky MH, Haus E. Circadian rhythms and clinical medicine withapplications to hypertension. Am J Hypertens. 2001;14(9 Pt 2):280S-290S.

11. Touitou Y, Haus E. Biologic Rhythms in Clinical and Laboratory Medicine.Heidelberg, Germany: Springer-Verlag; 1994.

12. Millar-Craig MW, Bishop CN, Raftery EB. Circadian variation of blood-pressure.Lancet. 1978;1(8068):795-797.

13. Rocco MB, Nabel EG, Selwyn AP. Circadian rhythms and coronary arterydisease. Am J Cardiol. 1987;59(7):13C-7C.

14. Kario K. Time for focus on morning hypertension: pitfall of currentantihypertensive medication. Am J Hypertens. 2005;18(2 Pt 1):149-151.

15. Gordon RD, Wolfe LK, Island DP, Liddle GW. A diurnal rhythm in plasma reninactivity in man. J Clin Invest. 1966;45(10):1587-1592.

16. Weitzman ED, Fukushima D, Nogeire C, Roffwarg H, Gallagher TF, Hellman L.Twenty-four hour pattern of the episodic secretion of cortisol in normal subjects.J Clin Endocrinol Metab. 1971;33(1):14-22.

17. Kario K, Shimada K, Pickering TG. Abnormal nocturnal blood pressure falls inelderly hypertension: clinical significance and determinants. J CardiovascPharmacol. 2003;41(suppl 1):S61-S66.

18. Kala R, Fyhrquist F, Eisalo A. Diurnal variation of plasma angiotensin II in man.Scand J Clin Lab Invest. 1973;31(4):363-365.

19. Portaluppi F, Bagni B, degli Uberti E, et al. Circadian rhythms of atrial natriureticpeptide, renin, aldosterone, cortisol, blood pressure and heart rate in normal andhypertensive subjects. J Hypertens. 1990;8(1):85-95.

20. Strawn WB, Ferrario CM. Mechanisms linking angiotensin II and atherogenesis.Curr Opin Lipidol. 2002;13(5):505-512.

21. Kario K. Caution for winter morning surge in blood pressure: a possible link withcardiovascular risk in the elderly. Hypertension. 2006;47(2):139-140.

22. Murakami S, Otsuka K, Kubo Y, et al. Repeated ambulatory monitoring reveals aMonday morning surge in blood pressure in a community-dwelling population.Am J Hypertens. 2004;17(12 Pt 1):1179-1183.

23. Woodhouse PR, Khaw KT, Plummer M, Foley A, Meade TW. Seasonalvariations of plasma fibrinogen and factor VII activity in the elderly: winterinfections and death from cardiovascular disease. Lancet. 1994;343(8895):435-439.

24. Muller JE. Circadian variation in cardiovascular events. Am J Hypertens.1999;12(2 Pt 2):35S-42S.

25. Muller JE, Tofler GH, Stone PH. Circadian variation and triggers of onset ofacute cardiovascular disease. Circulation. 1989;79(4):733-743.

26. Ishikawa J, Kario K, Eguchi K, et al. Regular alcohol drinking is a determinant ofmasked morning hypertension detected by home blood pressure monitoring inmedicated hypertensive patients with well-controlled clinic blood pressure: theJichi Morning Hypertension Research (J-MORE) study. Hypertens Res.2006;29(9):679-686.

27. Ishikawa J, Kario K, Hoshide S, et al. Determinants of exaggerated difference inmorning and evening blood pressure measured by self-measured blood pressuremonitoring in medicated hypertensive patients: Jichi Morning HypertensionResearch (J-MORE) Study. Am J Hypertens. 2005;18(7):958-965.

28. Mann SJ, James GD, Wang RS, Pickering TG. Elevation of ambulatory systolicblood pressure in hypertensive smokers: a case-control study. JAMA.1991;265(17):2226-2228.

29. Tamaki S, Nakamura Y, Yoshino T, et al. The association between morninghypertension and metabolic syndrome in hypertensive patients. Hypertens Res.2006;29(10):783-788.

30. Kuriyama S, Otsuka Y, Iida R, Matsumoto K, Tokudome G, Hosoya T. Morningblood pressure predicts hypertensive organ damage in patients with renaldiseases: effect of intensive antihypertensive therapy in patients with diabeticnephropathy. Intern Med. 2005;44(12):1239-1246.

31. Curtis AM, Cheng Y, Kapoor S, Reilly D, Price TS, Fitzgerald GA. Circadianvariation of blood pressure and the vascular response to asynchronous stress. Proc Natl Acad Sci USA.2007;104(9):3450-3455.

32. Polonia J, Amado P, Barbosa L, et al. Morning rise, morning surge and daytimevariability of blood pressure and cardiovascular target organ damage: a crosssectionalstudy in 743 subjects. Rev Port Cardiol. 2005;24(1):65-78.

33. Asayama K, Ohkubo T, Kikuya M, et al. Prediction of stroke by home "morning"versus "evening" blood pressure values: the Ohasama study. Hypertension.2006;48(4):737-743.

34. Kario K, Pickering TG, Umeda Y, et al. Morning surge in blood pressure as apredictor of silent and clinical cerebrovascular disease in elderly hypertensives: aprospective study. Circulation. 2003;107(10):1401-1406.

35. Kario K, Ishikawa J, Pickering TG, et al. Morning hypertension: the strongestindependent risk factor for stroke in elderly hypertensive patients. Hypertens Res.2006;29(8):581-587.

36. Ikeda T, Gomi T, Shibuya Y, et al. Morning rise in blood pressure is a predictorof left ventricular hypertrophy in treated hypertensive patients. Hypertens Res.2004;27(12):939-946.

37. Asmar R, Zanchetti A. Guidelines for the use of self-blood pressure monitoring: asummary report of the First International Consensus Conference. GroupeEvaluation & Measure of the French Society of Hypertension. J Hypertens.2000;18(5):493-508.

38. Imai Y, Ohkubo T, Kikuya M, Hashimoto J. Practical aspect of monitoringhypertension based on self-measured blood pressure at home. Intern Med.2004;43(9):771-778.

39. Imai Y, Otsuka K, Kawano Y, et al. Japanese Society of Hypertension (JSH)guidelines for self-monitoring of blood pressure at home. Hypertens Res.2003;26(10):771-782.

40. O'Brien E, Asmar R, Beilin L, et al. European Society of Hypertensionrecommendations for conventional, ambulatory and home blood pressuremeasurement. J Hypertens. 2003;21(5):821-848.

41. American Society of Hypertension releases guidelines on home and ambulatoryblood pressure monitoring. Am Fam Physician. 1996;54(4):1390.

42. Nordmann A, Frach B, Walker T, Martina B, Battegay E. Reliability of patientsmeasuring blood pressure at home: prospective observational study. BMJ.1999;319(7218):1172.

43. Yarows SA, Julius S, Pickering TG. Home blood pressure monitoring. ArchIntern Med. 2000;160(9):1251-1257.

44. Charbonnier FM. AAMI/ANSI standard for automatic or advisory externaldefibrillators. Association for the Advancement of Medical Instrumentation.American National Standards Institute. J Electrocardiol. 1993;26(suppl):147-150.

45. O'Brien E, Petrie J, Littler W, et al. The British Hypertension Society protocol forthe evaluation of automated and semi-automated blood pressure measuringdevices with special reference to ambulatory systems. J Hypertens.1990;8(7):607-619.

46. dabl Education Trust. Automated Devices for Clinical Use. Available at:www.dableducational.com/sphygmomanometers/devices_1_clinical.html#ClinTable. Accessed March 5, 2007.

47. Omron Healthcare. Omron HEM-70. Available at:www.omronhealthcare.com/enTouchCMS/app/viewDocument?docID=1736.Accessed March 8, 2007.

48. Hoshide S, Kario K, Hoshide Y, et al. Associations between nondipping ofnocturnal blood pressure decrease and cardiovascular target organ damage instrictly selected community-dwelling normotensives. Am J Hypertens.2003;16(6):434-438.

49. Ohkubo T, Asayama K, Kikuya M, et al. How many times should blood pressurebe measured at home for better prediction of stroke risk? Ten-year follow-upresults from the Ohasama study. J Hypertens. 2004;22(6):1099-1104.

50. Tsuji I, Imai Y, Nagai K, et al. Proposal of reference values for home bloodpressure measurement: prognostic criteria based on a prospective observation ofthe general population in Ohasama, Japan. Am J Hypertens. 1997;10(4 Pt 1):409-418.

51. Pickering T. Recommendations for the use of home (self) and ambulatory bloodpressure monitoring. American Society of Hypertension Ad Hoc Panel. Am JHypertens. 1996;9(1):1-11.

52. Mancia G. Reversed white-coat hypertension: definition, mechanisms andprognostic implications. J Hypertens. 2002;20(4):579-581.

53. Mancia G, Facchetti R, Bombelli M, Grassi G, Sega R. Long-term risk ofmortality associated with selective and combined elevation in office, home, andambulatory blood pressure. Hypertension. 2006;47(5):846-853.

54. Pickering TG, Davidson K, Gerin W, Schwartz JE. Masked hypertension.Hypertension. 2002;40(6):795-796.

55. Mule G, Caimi G, Cottone S, et al. Value of home blood pressures as predictor oftarget organ damage in mild arterial hypertension. J Cardiovasc Risk.2002;9(2):123-129.

56. Sakaguchi K, Horimatsu T, Kishi M, et al. Isolated home hypertension in themorning is associated with target organ damage in patients with type 2 diabetes. JAtheroscler Thromb. 2005;12(4):225-231.

57. Tsunoda S, Kawano Y, Horio T, Okuda N, Takishita S. Relationship betweenhome blood pressure and longitudinal changes in target organ damage in treatedhypertensive patients. Hypertens Res. 2002;25(2):167-173.

58. Edmonds D, Foerster E, Groth H, Greminger P, Siegenthaler W, Vetter W. Doesself-measurement of blood pressure improve patient compliance in hypertension?J Hypertens Suppl. 1985;3(1):S31-S34.

59. Marquez-Contreras E, Martell-Claros N, Gil-Guillen V, et al. Efficacy of a homeblood pressure monitoring programme on therapeutic compliance inhypertension: the EAPACUM-HTA study. J Hypertens. 2006;24(1):169-175.

60. Halme L, Vesalainen R, Kaaja M, Kantola I. Self-monitoring of blood pressurepromotes achievement of blood pressure target in primary health care. Am JHypertens. 2005;18(11):1415-1420.

(Based on the article starting on page 88) Choose the 1 most correct answer.

1. Where does the "master clock"that controls circadian rhythm existin the body?

Pituitary gland
Suprachiasmatic nucleus
Limbic system of the brain
Adrenal gland

2. What specific genes have beenisolated that may control morning-surgehypertension (MSH)?

Bmal1^-/-
Clock^mut
Npas2^mut
All of the above

3. A patient with hypertensionchecks his morning blood pressure(BP) after awaking, again around 3PM in his doctor's office, and againprior to bedtime (10:30 PM). His BPreadings are as follows: 150/90 mmHg, 148/85 mm Hg, and 155/93 mmHg, respectively. This is suggestiveof what type of hypertension?

Masked
Sustained
Morning
White-coat

4. A patient with hypertensionchecks his morning BP after awaking,again around 3 PM in his doctor'soffice, and again prior to bedtime.His BP readings are as follows:130/80 mm Hg, 160/95 mm Hg, and135/75 mm Hg, respectively. Whattype of hypertension is this patientexhibiting?

Masked
Sustained
Morning
White-coat

5. A patient with hypertensionchecks his morning BP after awaking,again around 3 PM in his doctor'soffice, and again prior to bedtime.His BP readings are as follows:180/100 mm Hg, 140/80 mmHg, and 130/82 mm Hg, respectively.What type of hypertension is thispatient exhibiting?

Masked
Sustained
Morning
White-coat

6. If the hypertension for thepatient in Question 5 is not controlled,which of the following couldpotentially occur?

Decrease in urine albuminexcretion
Decrease in left ventricularsize
Increase in risk of stroke
Increase in risk of neuropathy

7. If a patient is using a home bloodpressure (HBP) monitor to evaluatehis or her pressure, what would theupper limit of normal be for his orher BP?

130/85 mm Hg
135/85 mm Hg
140/90 mm Hg
145/95 mm Hg

8. What are some of the consequencesof the large, abrupt elevationin BP in patients with MSH?

Vascular inflammation
Endothelial damage
Vasoconstriction
All of the above

9. Which of the following may beresponsible for MSH?

Increased renin-angiotensin-aldosteroneactivity
Decreased sympathetic nervoussystem surges
Decreased vascular sensitivityto norepinephrine
Increased plasma calcium concentrations

10. Compared with BP readingsobtained in a doctor's office, whichof the following is true regardingHBP monitoring?

It is less accurate andreproducible.
It may improve drug therapyadherence.
It is not as prognostic.
It may reduce cardiovascularmortality.

11. Which of the following cuffoscillometricdevices has/havebeen shown to be more reliable?

upper-arm cuff
traditional wrist cuff
finger cuff
All are equally reliable

12. At what time of day shouldpatients check their HBP?

In the morning after waking up
In the morning after waking upand after lunch
In the morning after waking upand after eating supper
In the morning after waking upand prior to bedtime

13. According to the AmericanHeart Association (AHA), at a minimum,how long should a patientwait between BP measurements?

1 minute
3 minutes
5 minutes
10 minutes

14. A patient has purchased an HBPmonitor. How often would you recommendthat he or she check themonitor for accuracy?

Every 6 months
Every 1 to 2 years
Every month
Every 3 to 4 years

15. Which of the following patientpopulations may not benefit froman HBP monitor?

Patients with white-coathypertension
Patients with type 2 diabetes
Patients with atrial fibrillation
Patients with heart failure

16. A list of updated validated monitorscan be obtained from the AHA.

True
False

17. A patient with hypertensionchecks his morning BP after awaking,again around 3PM in his doctor'soffice, and again prior to bedtime.His BP readings are as follows:180/100 mm Hg, 135/85 mm Hg,and 160/90 mm Hg, respectively.What type of hypertension is thispatient exhibiting?