Timing of Orthostatic Blood Pressure Changes and Its Association With Orthostatic Symptoms and Falls at Very Old Ages: Findings From the ARIC Study

BACKGROUND: Assessment and treatment of orthostatic hypotension (OH) are recommended to prevent falls in older adults. However, the optimal timing of standing blood pressure (BP) assessments to identify clinically relevant OH remains unclear. METHODS: We measured 3 supine BP readings after 5 minutes of rest at 30-second intervals and 6 standing BP readings (timed at 0, 1, 2, 3, 4, and 5 minutes after standing) during the ARIC study (Atherosclerosis Risk in Communities) visit 10. OH was defined as a drop in BP (systolic ≥20 mm Hg or diastolic ≥10 mm Hg) on standing from the supine position. We quantified the prevalence and predictors of initial OH (immediately after standing), early OH (within 3 minutes), late OH (after 3 minutes), and sustained OH (all 6 minutes). We examined their associations with orthostatic symptoms and falls using logistic regression and negative binomial models, respectively. RESULTS: Of the 863 participants (mean age, 83.7 years), 41.3% had initial OH. Participants on antihypertensive medications had higher odds of all types of OH irrespective of controlled (<130/80 mm Hg) or uncontrolled (≥130/80 mm Hg) hypertension compared with those without hypertension (<130/80 mm Hg) and no antihypertensive use. Initial and early OH were strongly associated with orthostatic symptoms in the process of standing from the supine position (odds ratio, 2.34 [95% CI, 1.42-3.86]; odds ratio, 1.82 [95% CI, 1.11-2.98], respectively). Finally, participants with initial OH had higher fall rates (rate ratio, 1.45 [95% CI, 1.02-2.06]) than those without OH. CONCLUSIONS: Measuring BP within 3 minutes of standing, particularly the first BP measurement immediately after standing, may provide clinicians with important information on falls risk and orthostatic symptoms.