Hypertension Journal

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White-coat Hypertension
  JOHTN
REVIEW ARTICLE
White-coat Hypertension
Lexy Vijayan
Department of Internal Medicine, PRS Hospital, Thiruvananthapuram, Kerala, India
Address for correspondence: Dr. Lexy Vijayan, PRS Hospital, Thiruvananthapuram, Kerala, India.
Phone: +91-9744215144
E-mail: drlexy.manoj@gmail.com
Received: 22-11-2018; Accepted: 17-12-2018
doi: 10.15713/ins.johtn.0143
 
ABSTRACT
The term white-coat hypertension (WCHT) comes from the reference to the white coats traditionally worn by the doctors. It isalso called "isolated office or clinic hypertension." Thomas Pickering coined the term WCHT to denote individuals who were noton the treatment for hypertension but who had elevated office blood pressure and normal blood pressure measured at home or withambulatory blood pressure monitor. When your blood pressure is taken at home, the systolic value can be 10 mmHg lower than itwould be if taken by a doctor and 5 mm lower on the diastolic blood pressure value. For some people, the difference can be evengreater. The traditional definition of WCHT is based, therefore, on an elevated office blood pressure with a normal blood pressureduring the awake period with ambulatory blood pressure monitoring. The most recent European guidelines propose an alternativedefinition of WCHT, which encompasses subjects with office systolic/diastolic blood pressure readings of >140/90 mmHg and24 h blood pressure < 130/80 mmHg. This condition cannot be considered as innocent since it is associated with metabolicabnormalities as well as cardiac and vascular end-organ damage. Evidence has been provided that WCHT state is characterized byan increased risk of fatal and non-fatal cardiovascular (CV) events as compared to normotensive individuals. People with WCHTwere more likely to be female young less obese and more recently diagnosed with hypertension. The purpose of the review is toprovide new insights into the definition, characteristics, CV risk assessment, therapeutic implications, and all-cause mortality inpatients with WCHT.
Keywords: Ambulatory blood pressure monitoring, white-coat hypertension, sustained HTN
How to cite this article: Vijayan L. White-coat Hypertension.Hypertens 2019;5(1): 14-16.
Source of support: Nil
Conflict of interest: None
 
 

Introduction

The term white-coat hypertension (WCHT) describes asubgroup of untreated individuals with persistently elevatedoffice blood pressure but normal ambulatory blood pressurevalues. This isolated clinic hypertension is frequently diagnosedin current clinical practice. The prevalence of WCHT dependsmainly on the demographic and clinical characteristics of thesubjects as well as on the methods (including ambulatory orhome blood pressures measurement) and the blood pressurecutoffs used to define normal out-of-office values. Majority of theclinical studies have reported that WCHT accounts for 25-30%of individuals and the phenomenon is reasonably reproducible;however, whether WCHT is a benign phenomenon is stillunder debate. Failure to identify the condition results in a largeexpenditure on necessary drugs. Years of investigation haveshown that this condition cannot be regarded as "innocent"nature but with a greater CV risk and, hence, retains importantclinical implications.

 
The task force of the eighth international consensusconference on blood pressure monitoring recommendsambulatory blood pressure monitoring to exclude WCHT inuntreated patients when
  • Office blood pressure > 140/90 mmHg on >3 separate officevisits.
  • >2 Blood pressure measurements taken outside the officeare < 140/90 mmHg frequently using home blood pressuremonitoring and
  • There is no evidence of hypertensive end-organ damage.

The National Institute for Health and Clinical Excellenceguidelines advocate that every person with elevated office bloodpressure aged >18 years undergo ambulatory blood pressuremonitoring to rule out a diagnosis of WCHT with the potentialfor savings in health costs by virtue of unnecessary treatmentwith antihypertensive drugs.

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New insights on different aspects of WCHT Vijayan

Once ambulatory blood pressure has confirmed the diagnosisof WCHT, the European Society of Hypertension WorkingGroup on blood pressure monitoring recommends that thediagnosis be reconfigured in 3-6 months and followed upyearly with ambulatory blood pressure monitoring to detect anyevidence of progression to sustained hypertension.[1-6]

Etiology

Emotional factors such as anxiety or stress may be responsiblefor the microneurographic response in which pronouncedactivation of skin nerves and associated sympathetic inhibitionof muscle nerve traffic when physicians take the blood pressure.This anxious emotional response may act as a mechanism in thedevelopment of WCHT.[2,3]

Implications

The studies have shown that there is greater risk of futuresustained hypertension, high associated metabolic risk, and endorgandamage.[4]

Future Hypertension Risk

There is a greater risk of developing hypertension in whitecoat subjects based on in-office blood pressure and out-ofofficeblood pressure values. The condition of sustained bloodpressure >140/90 mmHg and mean 24 h blood pressure values< 125/79 mmHg or home blood pressure < 132/82 mmHg arewhite-coat hypertensives. 10-year follow-up study showed that43% of them had progressed to sustained hypertension. Hence,sustained hypertension was 2.5-fold higher for WCHT, evenafter adjusted for age.

Metabolic Risk

Evidence has supported the association between WCHT andmetabolic derangements which may precipitate CV events.When compared to the normotensive individuals, subjectswith WCHT may have high triglycerides, uric acid, and glucosevalues. These subjects with increased waist circumference andbody mass index show high blood pressure variability whichall contributes to cardiac vascular and renal involvement. Thepersistent impairment in glucose metabolism has been reportedin white-coat hypertensive subjects, and hence, the developmentof new-onset diabetes mellitus is much more high in white-coathypertensive patients than in normotensives.

End-organ Damage

Studies show that the development of target organ damagein white-coat hypertensive subjects is intermediate betweennormotensives and sustained hypertensives. At CV level, theremay be an increase in the left ventricular (LV) mass index, areduction in early to late mitral flow ratio (an index of the LVdistensibility) and greater values of the left atrial diameter.Untreated white-coat hypertensive subjects show the high-riskdevelopment of intima-media thickness. Early renal damage maybe assessed by urine microalbumin.

 
Treatment Strategies[4-6]

Maintain a Good Patient-health-care Professional
Relationship


WCHT may be addressed through the development of atherapeutic relationship between physician and patient. Effectivecommunication and relationship building can reduce thepatient's anxiety about their illness and about their interactionwith a physician. Communication between physician and patientis often considered the cornerstone of good medical care.

Relaxation Techniques

Some relaxation techniques such as breathing exercises ormeditation may help the patient to calm down before bloodpressure checking.

Supportive Management

It mainly includes lifestyle modification, weight reduction,and proper management of other risk factors such as diabetesmellitus, dyslipidemia, and renal dysfunction.

Drug Treatment

Antihypertensive medications may be considered in additionto the lifestyle modifications if there are any associated riskfactors including the end-organ damage. In unstable white-coathypertensive patients, the CV risk has been noted to be low than astable white-coat hypertensive patient. No any antihypertensivemedication is recommended for a stable white-coat hypertensivepatient with no additional risk factors and also for an unstablewhite-coat hypertensive patient.

Conclusion

WCHT is not considered as an innocent condition as it can beassociated with metabolic derangements, high CV risks, andother target organ damages, it has to be diagnosed earlier toprevent further complications. Even though there is no evidencebaseddata regarding treatment of WCHT, the European Societyof Hypertension/European Society of Cardiology guidelinessuggest that antihypertensive medications to be restricted tohigh-risk patients.

References
  1. Huang Y, Huang W, Mai W, Cai X, An D, Liu Z, et al. White-coathypertension is a risk factor for cardiovascular diseases and totalmortality. J Hypertens 2017;35:677-88.

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Vijayan New insights on different aspects of WCHT

  1. Cobos B, Haskard-Zolnierek K, Howard K. White coathypertension: Improving the patient-health care practitionerrelationship. Psychol Res Behav Manag 2015;8:133-41.
  2. Mancia G. Clinical significance of white-coat hypertension.J Hypertens 2016;34:623-6.
  3. Journal of the American college of Cardiology.
  4. Ogedegbe G. White coat effect: Unraveling its mechanics. Am JHypertens 2008;21:135.

 
  1. Franklin SS, Thijs L, Hansen TW, O'Brien E, Staessen JA. Whitecoat hypertension-new insights from recent studies. HypertensJ Am Heart Assoc 2013;62:982-7.

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