Prevalence of orthostatic hypertension and its association with cerebrovascular diagnoses in patients with suspected TIA and minor stroke.

PURPOSE

We aimed to compare the rate of stroke, transient ischemic attack, and cerebrovascular disease diagnoses across groups of patients based on their orthostatic blood pressure response in a transients ischemic attack clinic setting.

MATERIALS AND METHODS

We retrospectively analysed prospectively collected data from 3201 patients referred to a transient ischemic attack (TIA)/minor stroke outpatients clinic. Trained nurses measured supine and standing blood pressure using an automated blood pressure device and the patients were categorized based on their orthostatic blood pressure change into four groups: no orthostatic blood pressure rise, systolic orthostatic hypertension, diastolic orthostatic hypertension, and combined orthostatic hypertension. Then, four stroke physicians, who were unaware of patients' orthostatic BP response, assessed the patients and made diagnoses based on clinical and imaging data. We compared the rate of stroke, TIA, and cerebrovascular disease (either stroke or TIA) diagnoses across the study groups using Pearson's χ test. The effect of confounders was adjusted using a multivariate logistic regression analysis.

RESULTS

Cerebrovascular disease was significantly less common in patients with combined systolic and diastolic orthostatic hypertension compared to the "no rise" group [OR = 0.56 (95% CI 0.35-0.89]. The odds were even lower among the subgroups of patients with obesity [OR = 0.31 (0.12-0.80)], without history of smoking [OR 0.34 (0.15-0.80)], and without hypertension [OR = 0.42 (95% CI 0.19-0.92)]. We found no significant relationship between orthostatic blood pressure rise with the diagnosis of stroke. However, the odds of TIA were significantly lower in patients with diastolic [OR 0.82 (0.68-0.98)] and combined types of orthostatic hypertension [OR = 0.54 (0.32-0.93)]; especially in patients younger than 65 years [OR = 0.17 (0.04-0.73)] without a history of hypertension [OR = 0.34 (0.13-0.91)], and patients who did not take antihypertensive therapy [OR = 0.35 (0.14-0.86)].

CONCLUSION

Our data suggest that orthostatic hypertension may be a protective factor for TIA among younger and normotensive patients.