Frequency and determinants of white coat hypertension in mild to moderate hypertension - A primary care based study

Most of the previous studies on white coat hypertension were performed in h ypertension clinics or academic settings and included relatively small seri es of patients. Consequently, the prevalence of white coat hypertension in primary care settings and the clinical and epidemiologic characteristics of this subgroup of patients are not well known. We performed this study to e stimate the frequency of white coat hypertension in a population of mildly to moderately hypertensive subjects attended in a primary care setting and to examine possible epidemiologic and clinical factors that may identify th ese patients. Patients included in the study underwent clinical interview, measurement of clinic blood pressure (BP) on three visits, determination of serum lipids, glucose, uric acid, and urinary albumin excretion, 24-h ambu latory BP monitoring, and M-mode and Doppler echocardiography. Patients wer e classified as white coat hypertensives if their daytime ambulatory BP wer e < 135/85 mm Hg, We studied 345 patients, 136 (39%) of whom were diagnosed with white coat h ypertension. The frequency of white coat hypertension was inversely proport ional to the severity of clinic BP values. The diagnosis of white coat hype rtension was independently associated with female gender and low educationa l level. Left ventricular mass index and urinary albumin excretion were low er in the white-coat hypertensive group compared with the group with sustai ned hypertension. Our results show that a high proportion of patients with mild to moderate hypertension attended in a primary care setting have white coal hypertension. Some clinical characteristics may be helpful in the ide ntification of this group of subjects. White coal hypertensives show less t arget-organ damage than sustained hypertensive patients. Am T Hypertens 199 9;12:251-259 (C) 1999 American Journal of Hypertension, Ltd.