Masked Hypertension Assessed by Ambulatory Blood Pressure Versus Home Blood Pressure Monitoring: Is It the Same Phenomenon?

• Published in: American journal of hypertension Vol. 18; no. 6; pp. 772 - 778
• Main Authors: Stergiou, George S., Salgami, Eleanna V., Tzamouranis, Dimitris G., Roussias, Leonidas G.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.06.2005; Oxford University Press; Elsevier Science
• Subjects: ambulatory blood pressure; Arterial hypertension. Arterial hypotension; Biological and medical sciences; Blood and lymphatic vessels; Blood Pressure - physiology; Blood Pressure Determination - methods; Blood Pressure Monitoring, Ambulatory; Cardiology. Vascular system; Clinical manifestations. Epidemiology. Investigative techniques. Etiology; Female; Follow-Up Studies; Fundamental and applied biological sciences. Psychology; Hemodynamics. Rheology; Humans; Hypertension - diagnosis; Hypertension - physiopathology; Male; Masked hypertension; Medical sciences; Middle Aged; Office Visits; Outpatients; Self Care; self-monitored home blood pressure; Sensitivity and Specificity; Vertebrates: cardiovascular system; self-monitored home blood pressure; ambulatory blood pressure; Masked hypertension; Hypertension; Cardiovascular disease; Arterial pressure; Blood pressure; Ambulatory; Comparative study; Monitoring
• ISSN: 0895-7061; 1879-1905; 1941-7225
• DOI: 10.1016/j.amjhyper.2005.01.003

Masked hypertension is defined as normal clinic blood pressure (CBP) and elevated out-of-clinic blood pressure assessed using either self-monitoring of blood pressure (BP) by the patients at home (HBP) or ambulatory BP (ABP) monitoring. This study investigated the level of agreement between ABP and HBP in the diagnosis of masked hypertension. Participants referred to an outpatient hypertension clinic had measurements of CBP (two visits), HBP (4 days), and ABP (24 h). The diagnosis of masked hypertension based on HBP (CBP <140/90 mm Hg and HBP ≥135/85) versus ABP (CBP <140/90 and awake ABP ≥135/85) was compared. A total of 438 subjects were included (mean age ± SD, 51.5 ± 11.6 years; 59% men and 41% women, 34% treated and 66% untreated). Similar proportions of subjects with masked hypertension were diagnosed by ABP (14.2%) and HBP (11.9%). In both treated and untreated subjects, the masked hypertension phenomenon was as common as the white coat phenomenon. Among 132 subjects with normal CBP, there was disagreement in the diagnosis of masked hypertension between the HBP and the ABP method in 23% of subjects for systolic and 30% for diastolic BP (κ 0.56). When a 5–mm Hg gray zone for uncertain diagnosis was applied to the diagnostic threshold, the disagreement was reduced to 9% and 6% respectively. Similar proportions of subjects with masked hypertension are detected by ABP and HBP monitoring. Although disagreement in the diagnosis between the two methods is not uncommon, in the majority of these cases the deviation of the diagnostic BP above the threshold in not clinically important. Both ABP and HBP monitoring appear to be appropriate methods for the detection of masked hypertension.