Sympathetic activation in resistant hypertension: theory and therapy.

Resistant hypertension defined as requiring 3 or more complementary antihypertensive drugs at maximally tolerated doses accounts for approximately 3% to 4% of all cases of hypertension. Its increased incidence over the past decade is related to the increase in obesity in the Western world. There are a number of dietary factors that affect sympathetic tone including sodium intake apart from increased body mass. This article discusses the mechanisms of sympathetic stimulation and activation in the context of animal models and human studies. In addition, there is a review of clinical trials with and without device therapy that summarizes the clinical findings. Effective management should be based on pathophysiologic principles and a focus on blood pressure reduction to levels well below 150/90 mm Hg because outcome trial evidence and Food and Drug Administration guidance supports this construct. The key to success of device-based therapy depends on identifying the cohort with true resistant hypertension that can benefit from therapies that are adjuncts to pharmacotherapy. Physicians need to concentrate on educating the patient on lifestyle modifications and themselves on use of proper combinations of antihypertensive medications. If this approach fails to result in a safe level of blood pressure then the patient should be referred to a board-certified clinical hypertension specialist.