White coat effect and white coat hypertension: one and the same?
AbstractWhite coat hypertension (WCHT) and white coat effect (WCE) are often thought to be of the same entity. They are in factdifferent conditions which carry distinctive definitions and prognostic significance. WCHT is diagnosed when office bloodpressure (OBP) is ≥140/90 mmHg on at least 3 occasions, while the average daytime or 24-hour blood pressure is <135/85mmHg.It is common with 15% prevalence in the general population and may account for over 30% of individuals in whomhypertension is diagnosed. Although individuals with WCHT were reported to have a better cardiovascular (CV) prognosiswhen compared to those with sustained hypertension and masked hypertension; they were also shown to have a greaterprevalence of target organ damage (TOD) and metabolic abnormalities than that of normotensive subjects. In contrast, WCEis defined as the transient elevation of OBP induced by the alerting response to a doctor or a nurse. WCE can occur in bothnormotensive and hypertensive persons; and is not substantially influenced by reassurance and familiarisation. There isconflicting evidence with regards to prognostic significance of WCE, where most data indicated that it does not predict futureTOD, CV morbidity or mortality; with some studies showed otherwise. This case scenario aims to solve the diagnosticperplexity with regards to WCHT and WCE, followed by an evidence-based commentary of how to best manage suchconditions.
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