RESUMO
BACKGROUND: This study assessed the diagnostic reliability of automated office blood pressure (OBP) measurements in treated hypertensive patients in primary care by evaluating the prevalence of white coat hypertension (WCH) and masked uncontrolled hypertension (MUCH) phenomena. METHODS: Primary care physicians, nationwide in Greece, assessed consecutive hypertensive patients on stable treatment using OBP (1 visit, triplicate measurements) and home blood pressure (HBP) measurements (7 days, duplicate morning and evening measurements). All measurements were performed using validated automated devices with bluetooth capacity (Omron M7 Intelli-IT). Uncontrolled OBP was defined as ≥140/90 mmHg, and uncontrolled HBP was defined as ≥135/85 mmHg. RESULTS: A total of 790 patients recruited by 135 doctors were analyzed (age: 64.5 ± 14.4 years, diabetics: 21.4%, smokers: 20.6%, and average number of antihypertensive drugs: 1.6 ± 0.8). OBP (137.5 ± 9.4/84.3 ± 7.7 mmHg, systolic/diastolic) was higher than HBP (130.6 ± 11.2/79.9 ± 8 mmHg; difference 6.9 ± 11.6/4.4 ± 7.6 mmHg, p < 0.001). WCH phenomenon (high OBP with low HBP) was observed in 22.7% of the patients, MUCH (low OBP with high HBP) in 15.8%, uncontrolled hypertension (high OBP with high HBP) in 29.9%, and controlled hypertension (low OBP with low HBP) in 31.6%. In multivariate logistic regression analysis, WCH was determined by stage-1 systolic hypertension (odds ratio [OR] 8.6, 95% confidence intervals [CI] 5.7, 13.1) and female gender (OR 1.6, 95% CI 1.1, 2.4), whereas MUCH was determined by high-normal systolic OBP (OR 6.2, 95% CI 3.8, 10.1) and male gender (OR 2.0, 95% CI 1.2, 3.1). CONCLUSIONS: In primary care, automated OBP measurements are misleading in approximately 40% of treated hypertensive patients. HBP monitoring is mandatory to avoid overtreatment of subjects with WCH phenomenon and prevent undertreatment and subsequent excess cardiovascular disease in MUCH.