Resistant hypertension: Definition, evaluation, and new therapeutic approaches to treatment

Resistant hypertension is defined as blood pressure above the patient's goal despite the use of 3 or more antihypertensive agents from different classes at optimal doses, one of which should ideally be a diuretic. Although the exact prevalence of resistant hypertension is currently unknown, indirect evidence from population studies and clinical trials suggests that it is a relatively common clinical problem. The prevalence of resistant hypertension is projected to increase, owing to the aging population and increasing trends in obesity, sleep apnea, and chronic kidney disease. Evaluation of patients with resistive hypertension should first confirm that they have true resistant hypertension by ruling out or correcting factors associated with pseudoresistance such as white coat hypertension, suboptimal blood pressure measurement technique, poor adherence to prescribed medication, suboptimal dosing of antihypertensive agents or inappropriate combinations, the white coat effect, and clinical inertia. Management includes lifestyle and dietary modification, elimination of medications contributing to resistance, and evaluation of potential secondary causes of hypertension. Education and reinforcement of life-style issues that affect BP, such as sodium restriction, reduction of alcohol intake, and weight loss if obese, are critical in treating resistant hypertension. Pharmacological treatment should be tailored to the patient's profile and focus on the causative pathway of resistance. Exclusion of preparations that contribute to true BP treatment resistance, such as nonsteroidal anti-inflammatory agents, cold preparations, and certain herbs, is also important. Lastly, BP control can only be achieved if an antihypertensive treatment regimen is used that focuses on the genesis of the hypertension. An example is volume overload, a common but unappreciated cause of treatment resistance. Use of the appropriate dose and type of diuretic provides a solution to overcome treatment resistance in this instance. Patients with uncontrolled hypertension despite receiving an optimal therapy are candidates for newer interventional therapies such as carotid baroreceptor stimulation and renal denervation.