Thomas L. Schwenk, MD and Allan S. Brett, MD Reviewing Juraschek SP et al., JAMA Intern Med 2017 Jul 24;
Blood pressure readings within 1 minute might be more useful in predicting fractures, falls, and other adverse events.
According to a 2011 consensus statement, blood pressure (BP) measurement to assess orthostatic hypotension should be done “within 3 minutes of standing” (Clin Auton Res 2011; 21:69). To determine the value of measuring BP during the first 2 minutes after standing, researchers conducted this prospective cohort study that involved 11,249 middle-aged adults (mean age, 54; many with cardiovascular disease or risk factors, or on medications). Orthostatic hypotension (defined as systolic drop of ≥20 mm Hg or diastolic drop of ≥10 mm Hg) was assessed at baseline, with BP readings taken with an automatic cuff every 25 seconds as many as 5 times after a patient rose from a supine to a standing position.
Presence of orthostatic hypotension at the first measurement (but not at other measurement times) was associated significantly with self-reported history of dizziness on standing. During median follow-up of 23 years, about 12,000 adverse events (i.e., falls, fractures, syncopal episodes, motor vehicle accidents, and death) were recorded. Orthostatic hypotension at measurements 1 and 2 (i.e., within 1 minute) were associated most consistently and strongly with excess risk for all adverse events, except for syncope and death, which were associated significantly with orthostatic hypotension at all five time points.
This study reinforces the association between orthostatic hypotension and serious adverse events, affirms the importance of accurate diagnosis because of these risks, and suggests that orthostatic hypotension could be assessed more conveniently — within 1 minute of standing rather than waiting for 3 minutes. However, keep in mind that patients occasionally present with so-called “delayed orthostatic hypotension” (occurring after 3 minutes of standing; NEJM Gen Med Dec 1 2015 and Neurology2015; 85:1362); standing BP measurement should be extended beyond 3 minutes in patients who observe that syncopal or presyncopal symptoms don’t emerge until several minutes after standing.