Masked hypertension: A common but insidious presentation of hypertension

Abstract

M asked hypertension (MH) is strongly linked to an increased risk of heart disease and stroke (1-4). Mounting evidence suggests that MH must be taken into account in the assessment of blood pressure (BP), but little is known about how masked hypertensive patients are identified or how they should be managed. Despite prevalence estimates of at least 8% to 10% in the general population and a prognosis similar to sustained hypertension, the term, the meaning and the importance of MH are not widely understood. The present article provides some background on MH, describes its clinical importance and discusses some aspects of management in clinical practice. What is MH?MH is present when a normal office BP (OBP) is recorded in a patient with ambulatory BP (ABP) or home BP (HBP) readings in the hypertensive range (5). As the term implies, the hypertension is real but is masked to the physician. Patients with this condition have a normal or, more commonly, high normal OBP of less than 140/90 mmHg. Although ABP and HBP testing is not performed routinely in patients whose BP is less than 140/90 mmHg, various research studies have examined the relationship between normal OBP and ABP or HBP in a variety of populations. Over the past three years, four large, prospective studies (1-4) have reported that patients with MH exhibit a risk profile similar to those who have sustained hypertension.However, many health care professionals are unfamiliar with the concept of MH. This is possibly because of inconsistent nomenclature in the scientific or medical literature. However, the phenomenon of MH is not new. The classic paper on ABP monitoring was written by Perloff et al in 1983 (6), and demonstrated not only the superiority of ABP over OBP in predicting clinical outcomes, but also showed poorer outcomes in patients who had higher ABP values compared with their borderline or mildly hypertensive OBP. Since then, others who have observed this same phenomenon have called it a variety of names, including white coat normotension (7), reverse white coat (8), inverse white coat (9), home or isolated home hypertension (7,10), isolated ambulatory hypertension (11), isolated uncontrolled hypertension at home (12) and occult office hypertension (13). Pickering et al (5) suggested the term 'masked hypertension', and this term appears to have become the standard terminology to describe patients who have a normal OBP but elevated HBP or ABP. A patient has masked hypertension when his office blood pressure is less than 140/90 mmHg but his ambulatory or home blood pressure readings are in the hypertensive range. Several recent studies have demonstrated that cardiovascular risk is similar between those with masked hypertension and those with sustained hypertension. The prevalence of masked hypertension in Canada is not known, but data from other countries suggest rates greater than 8%. Physicians need to use careful clinical judgment to identify and treat subjects with masked hypertension. The present review discusses masked hypertension, its imp...

Call to Action on Use and Reimbursement for Home Blood Pressure Monitoring

“…Masked hypertension occurs when a patient's office BP is Ͻ140/90 mm Hg but ambulatory or home readings are in the hypertensive range (typically Ͼ135/85 mm Hg). 86 It conveys the same cardiovascular risk as sustained hypertension, and therefore it is important that it is detected. 87,88 The prevalence of masked hypertension may be Ϸ10% in the general population, 81,87,89 but at the present time there is no consensus in regard to how it should be detected or treated in people who have not been diagnosed as hypertensive.…”

Masked hypertension and its associated cardiovascular risk in young individuals: the African-PREDICT study

“…[3][4][5][6] The more commonly known white coat hypertension is in contrast to MHT and results in patients being unnecessarily pharmaceutically treated for hypertension. 7 MHT is a concern as patients are less easily diagnosed and are therefore untreated and unaware of their elevated cardiovascular risk.…”

Call to Action on Use and Reimbursement for Home Blood Pressure Monitoring

“…86 It conveys the same cardiovascular risk as sustained hypertension, and therefore it is important that it is detected. Masked hypertension occurs when a patient's office BP is G140/90 mm Hg but ambulatory or home readings are in the hypertensive range (typically 9135/85 mm Hg).…”