Clinical Briefs-By Louis Kuritzky, MD

Task Force V: White-Coat Hypertension

It is not uncommon for some patients to manifest an elevation of blood pressure only in a medical setting, a circumstance variously designated as white-coat hypertension (WCH), isolated office hypertension, clinic hypertension, and other names. The most common definition is the presence of consistently elevated blood pressure measured in the office, in the company of consistently normal blood pressure measured in nonmedical settings. Similarly, the term "white coat effect" has been coined to indicate the difference between measured ambulatory blood pressure.

WCH is present in about 20% of individuals designated as having hypertension. The magnitude of the white-coat effect appears to increase with increasing age, and disproportionately involves systolic blood pressure; that is, the lower blood pressure found at home is primarily a difference in systolic measurements, while diastolic pressure shows substantially less variation.

Whether target organ damage results from WCH is a matter of debate, but the predominance of information suggests little measurable consequences in such important realms as left ventricular hypertrophy. On the other hand, WCH is associated with microalbuminuria, albeit to a lesser degree than sustained hypertension.

Overall morbidity and mortality for WCH is small on an absolute basis, being minimally to only modestly increased compared to normals, and never approaching the magnitude of frankly hypertensive patients.

A final consensus on the consequences of WCH remains to be achieved. Since a substantial minority of WCH patients go on to have sustained hypertension in a fairly brief time period (11-37% over 3-5 years), patients with WCH are recommended to undergo follow-up on an indefinite basis.

Pickering TG, et al. Blood Press Monit 1999;4:333-341.