Secondary causes of hypertension.

Secondary hypertension is the presence of a specific condition known to cause hypertension, which may be the primary cause or a contributing factor in a patient who already has primary hypertension. Although uncommon, it may cause major morbidity for a subset of patients. This article provides an overview of the range of secondary causes, including key clinical features and appropriate diagnostic and treatment options. Selection of patients for testing should incorporate historical and clinical clues, previous treatment course, and comorbidities. Decisions regarding the extent of secondary evaluation require consideration of the likelihood of diagnosis, the patient's overall health status and prognosis, and balancing the risks of intervention against the risks of missing a diagnosis. Referral is advised when these risks seem prohibitive or if there are questions regarding the selection of the most optimal studies or the extent of intervention to pursue when blood pressure remains uncontrolled.