Prevalence and clinical significance of a greater ambulatory versus office blood pressure ('reversed white coat' condition) in a general population.
BACKGROUND
Attention has recently been directed to a condition termed 'reversed white coat' because of an average 24 h ambulatory blood pressure (BP) uncharacteristically greater than office BP. No data are available, however, on the prevalence of this condition in the general population, as well as on its relationship to BP, age, gender, antihypertensive treatment and cardiac organ damage.


METHODS
In 3200 individuals (participation rate 64%), randomly selected to be representative of the residents of Monza (Milan, Italy) for sex and decades of age (25 to 74 years), we measured office BP (average of three measurements, sphygmomanometry), ambulatory BP (automatic readings every 20 min, Spacelabs 90207) and left ventricular mass (echocardiography).


RESULTS
A 'reversed white coat' condition (identified when 24-h average ambulatory systolic, diastolic or mean were higher than the corresponding office values) was seen in 15% (diastolic) to 26% (systolic) of the population as a whole. Prevalence was greater (34-40%) when the difference between office and daytime BP was considered but in both instances it remained less than the prevalence of the white-coat phenomenon. A reversed white-coat condition was similarly frequent in males and females and showed a steep reduction with age and increasing office BP values. Prevalence was greater in hypertensive subjects in whom treatment achieved BP control than in untreated or unsatisfactorily treated individuals. Within each quartile of 24-h or office BP, left ventricular mass index adjusted for demographic and biochemical values was similar in reversed white coat versus the remaining subjects. The absence of any association with left ventricular hypertrophy scores against the clinical significance of this phenomenon.
Bombelli
Michele
M
Clinica Medica, Dipartimento di Medicina Clinica, Prevenzione e Biotecnologie Sanitarie, University of Milano-Bicocca, Ospedale S. Gerardo, Monza (MI), Italy.
Sega
Roberto
R
Facchetti
Rita
R
Corrao
Giovanni
G
Polo Friz
Hernan
H
Vertemati
Andrea Maria
AM
Sanvito
Riccardo
R
Banfi
Elena
E
Carugo
Stefano
S
Primitz
Laura
L
Mancia
Giuseppe
G
D000328:Adult; D000368:Aged; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory / Q000706:statistics & numerical data*; D002940:Circadian Rhythm; D004452:Echocardiography; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000453:epidemiology*; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging / Q000453:epidemiology; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010824:Physicians' Offices; D015995:Prevalence; D011379:Prognosis