WHITE COAT EFFECT AT PRIMARY-CARE - AN AN ALYSIS IN PATIENTS WITH RECENTLY DIAGNOSED HYPERTENSION

BACKGROUND: In a non-selected group of hypertensive patients with a ne w diagnosis at primary care, blood pressures obtained in the office (o BP) are compared to ambulatory ones (aBP). White coat hypertension (WC H) and white coat phenomenon (WCP) are estimated to evaluate a white c oat effect on such population. PATIENTS AND METHODS: An ambulatory blo od pressure monitoring (ABPM) was performed to 91 hypertensive patient s (55 females) from 21 to 70 years-old, with consecutive diagnosis in 4 office rooms in an health center (oBP mean greater than or equal to 140 mmHg for systolic blood pressure and/or 90 mmHg for diastolic bloo d pressure during three measures at least). WCH was defined by systoli c aBP less than or equal to 135 mmHg and diastolic less than or equal to 85 mmHg, simultaneously, and WCP by oBP-aBP diferences greater than or equal to 20 and/or 10 mmHg (for respective systolic and diastolic blood pressure). RESULTS: oBP systematically exceeded aBP with wide va riations for each subject (difference mean +/- SD: 15 +/- 13/7 +/- 9 m mHg for systolic/diastolic), sex (female: 19 +/- 12/11 +/- 9, male 8 /- 11/2 +/- 9) and depending on the observer who made the measure, WCH was detected in 27 patients (22 females), and WCP in 47 (37 females), so 30% (confidence interval [CI]: 21-40%) and 52% (CI: 41-62%) respec tive prevalences are supposed. CONCLUSIONS: Within primary care, white coat effect causes a substantial hypertension sobrediagnosis as quant itative as qualitatively. Confirming measures made by nurses and addit ionally, ABPM for women, seem to lessen this effect.