'Transient immediate orthostatic hypotension' is preferable to 'initial' orthostatic hypotension

Area of Science:

• Physiology
• Cardiovascular Medicine
• Clinical Nomenclature

Background:

• A common physiological event involves a transient drop in systemic blood pressure (BP) upon moving to an upright posture.
• Severe drops can cause symptoms like lightheadedness and falls, with a systolic BP drop >40 mmHg within 15s of standing defined as initial orthostatic hypotension (iOH).
• The term 'initial OH' implies a subsequent hypotensive event, which is often not the case for this brief, self-resolving BP drop.

Purpose of the Study:

• To address the inaccurate implications of the term 'initial orthostatic hypotension' (iOH).
• To propose more accurate terminology for transient, self-resolving drops in blood pressure upon standing.
• To foster clearer communication in clinical and research settings regarding orthostatic hypotension.

Main Methods:

• Review and analysis of the current understanding and definition of initial orthostatic hypotension (iOH).
• Evaluation of the temporal characteristics and resolution patterns of posture-induced hypotension.
• Proposal of alternative nomenclature based on the observed physiological response.

Main Results:

• The current term 'initial OH' inaccurately suggests an imminent subsequent hypotensive event.
• The described BP drop is typically solitary, brief (resolving within 15-30 seconds), and spontaneously resolves.
• Existing nomenclature does not accurately capture this common, transient hypotensive event without implying further episodes.

Conclusions:

• The term 'initial OH' should be retired due to its misleading implications.
• Recommended new terms are 'immediate OH' or 'transient immediate OH' to better describe the early-onset, brief nature of the event.
• The proposed nomenclature aims for greater accuracy in describing this common physiological occurrence, while retaining the abbreviation 'iOH'.