Diagnosing orthostatic hypotension: a narrative review of the evidence.

BACKGROUND

Orthostatic hypotension (OH) is very common, particularly in older populations. Diagnostic criteria exist but appear to be arbitrary rather than evidence based. This review will visit the evidence for diagnostic strategies for OH.

DATA SOURCES: Medline (OvidSP), EMBASE (OvidSP), ISI Web of Science, the Health Technology Assessments Database and the Cochrane Library.

AREAS OF AGREEMENT: A 5-min rest is required before measuring baseline. An active stand with continuous blood pressure (BP) monitoring is preferable to a tilt test to identify initial OH in particular. At least 2 min in the upright position is required. A systolic drop of 20 or a diastolic drop of 10 is supported by the evidence. Reproducibility when testing for OH is poor.

AREAS OF CONTROVERSY: Is the active stand preferable to the tilt test to diagnose classical OH? Although continuous BP monitoring increases diagnostic rates, does it improve clinical outcomes? Should symptoms be used to inform diagnosis?

AREAS TIMELY FOR RESEARCH: Establishing the long-term clinical outcomes for transient drops in BP detected on continuous, non-invasive monitoring. Evaluating the different patterns of BP drop to aid diagnosis and direct treatment.