Postural hypotension: causes, clinical features, investigation, and management.

Postural hypotension may result from various neurogenic and non-neurogenic causes. It may be a key feature of certain disorders, such as the primary chronic autonomic failure syndromes; it can complicate a variety of diseases, such as diabetes mellitus; and its prevalence increases with advancing age. When symptomatic, it may result in loss of consciousness and thus cause injury. Postural hypotension can be suspected from the patient's history and is readily documented in the clinic by measuring lying and standing blood pressure. The diagnosis ideally should be confirmed in the laboratory with additional tests to determine the cause and evaluate the functional deficit, so as to aid treatment. Treatment of the causative disorder is often curative when there are non-neurogenic causes. A combination of nonpharmacological and pharmacological measures is needed in the management of neurogenic postural hypotension.