A Detailed Classification of Neurogenic Orthostatic Hypotension According to the Pattern of Orthostatic Blood Pressure Drop in Patients with Orthostatic Intolerance

Background: To investigate the patterns of blood pressure (BP) decrement during the tilt, to compare the pattern of orthostatic hypotension (OH) and sympathetic index (SI) from the Valsalva maneuver (VM), and to identify whether the pattern of OH can predict the severity of autonomic failure.Methods: From January 2015 to July 2017, 551 consecutive patients with neurogenic OH were enrolled. All patients performed a standardized battery of autonomic tests, including the head-up tilt (HUT) test and VM using Finometer devices for recording beat-to-beat BP. SIs were calculated from the VM. The composite autonomic severity score (CASS) adrenergic subscore was also obtained to evaluate the severity of sympathetic adrenergic failure.Results: We classified OH into nine groups according to the patterns of orthostatic BP decrement during HUT. The two most common patterns of OH were classic stable OH (n=193) and classic OH with delayed normalization (n=102). Patients with classic stable OH and classic OH with delayed worsening had a more severe degree of sympathetic adrenergic failure as assessed with SI 5 and SI 4 from the VM, and a higher CASS adrenergic subscore than patients with other patterns of OH. There were no differences of autonomic parameters between the two delayed OH groups.Conclusions: The different patterns of orthostatic BP decrement may reflect underlying different pathophysiologic mechanisms causing OH. The pattern of orthostatic BP decrement can help to predict the degree of sympathetic adrenergic autonomic failure.