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Hypertension affects about 30% of adults in the United States. This number is expected to grow as the population ages. High blood pressure has aptly been termed “the silent killer,” as its presence has been shown to be associated with heart blockages, heart failure, stroke, and kidney failure.
Despite this high prevalence, it is estimated that fewer than half of patients with high blood pressure have it under adequate control. The reasons for the low rates of blood pressure control are various, including poor access to medical care and to medications. Some patients may also feel reluctant to take medications for a condition that has no obvious symptoms. In addition, a number of patients have resistant hypertension that requires intensive evaluation and treatment.
Resistant hypertension is defined as blood pressure that remains higher than it should be despite the use of three or more medications from different classes. As many as 15% of treated patients with hypertension may have resistant hypertension. These patients are at high risk for cardiovascular events (such as heart attacks and strokes) and may need extensive evaluation and treatment in order to reach their blood pressure targets. The Johns Hopkins Center for Hypertension is designed to assist such patients in reaching and maintaining a safe level of blood pressure.
White Coat Hypertension
Patients who have elevated blood pressure readings in the doctor’s office but normal readings when taken outside of the clinical setting are said to have “white coat hypertension”. This condition may be present in as many as 30% of patients, potentially leading to a mistaken diagnosis of hypertension. Additionally, patients with existing hypertension may be labeled with resistant disease even though their blood pressure may be well controlled on their current regimen. Ambulatory blood pressure monitoring (ABPM) is an effective way to distinguish patients with white coat hypertension from those in need of more intensive therapy. The Johns Hopkins Center for Hypertension uses diagnostic tools such as ABPM to assure proper management of patients’ blood pressure.
As many as 30% of patients with normal blood pressure readings in the doctor’s office may be found to have hypertension when measured by ABPM. Patients with this masked hypertension have been shown to be at significantly increased risk of cardiovascular events and death. Many of these patients may show signs of the effects of elevated blood pressure (for example, left ventricular hypertrophy), despite normal office readings. At the Johns Hopkins Center for Hypertension, these patients may be diagnosed early and monitored through use of ABPM.