Background: Postural hypotension and dizziness are common findings in elderly individuals. Although postural hypotension and postural dizziness are often perceived to be strongly associated entities, evidence to support this view in sparse. In addition, there is a lack of knowledge regarding the relationship of postural hypotension and postural dizziness to potential clinical outcomes, such as falls, syncope, and restricted activity.
Methods: We utilized a cross-sectional examination to study the prevalence and correlates of postural hypotension (drop in systolic blood pressure of greater than or equal to 20 mm Hg after 1 minute of standing) and postural dizziness (self-reported dizziness on standing) in 9704 nonblack, ambulatory women aged 65 years and older enrolled in the multicenter Study of Osteoporotic Fractures. First, we examined postural hypotension and postural dizziness as outcomes of risk factors that included medical conditions, medications, and physical findings. Then, we examined falls, syncope, and impaired functional status as outcomes of postural hypotension and postural dizziness.
Results: Postural hypotension and postural dizziness were common findings, noted in 14% and 19% of subjects, respectively. However, they were not highly correlated with each other and did not share the same risk factors or associated outcomes. Postural dizziness was more strongly associated than was postural hypotension with history of falling (age-adjusted odds ratios, 1.32 vs 1.02), history of syncope (1.94 vs 1.35), and impaired functional status (1.95 vs 0.76).
Conclusion: Assessment of dizziness on standing appears to be more important than measurement of postural blood pressure change in ascertaining functional status and risk of falls and syncope in elderly individuals. Future prospective studies of postural dizziness are needed to confirm its value as a predictor of clinical outcomes.