Abstract WP282: Association of Very Short Interval Blood Pressure Variability With Stroke

Abstract

Background: While blood pressure variability (BPV) is associated with poor cardiovascular outcomes, the relationship between BPV obtained in a very short interval and stroke is unknown. We aim to examine the association between very short interval BPV and a history of stroke. Hypothesis: Higher BPV is associated with the likelihood of having a stroke. Methods: A cross-sectional study using 2017-2020 NHANES included 3 consecutive BP measurements taken 60 seconds apart. The average real variability (ARV) of systolic and diastolic BP (AVR-SBP and AVR-DBP) was assessed as an average of absolute difference in consecutive BP. The association of AVR-SBP and AVR-DBP and the history of stroke was examined by multiple logistic regression. Results: Of 9,693 adult participants, mean±SD age was 50±19 years and 51% were female. Up to 5% (487 patients) had a history of stroke. Mean of the three average SBP and DBP were 120±20 and 72±12 mmHg, respectively. Median (IQR) of ARV-SBP was 3.5 (2, 6) mmHg and of ARV-DBP was 2.4 (1.5, 4) mmHg. Patients with stroke had significantly higher SBP and ARV-SBP, but not DBP and ARV-DBP compared to non-stroke patients (mean difference (95%CI) of SBP 11 (9, 13); ARV-SBP 0.7, (0.4, 1.1); DBP 0.7 (-0.5, 1.9); ARV-DBP 0.1 (-0.2, 0.4)). For every one mmHg increase in ARV-SBP, there was a 4.6% significantly greater odds of stroke (OR (95%CI) 1.05 (1.02, 1.07)), while there were 1.6% greater odds of stroke for every one mmHg increase in ARV-DBP but no statistical significance (OR 1.02 (0.98, 1.05)). After adjusting for age, gender, race, ethnicity, and BMI, the odds of stroke were 2.8% significantly higher for every one mmHg increase in ARV-SBP (OR 1.03 (1.00, 1.05)) and the ARV - stroke association remained non-significant. ARV-SBP was only associated with stroke in patients who were diagnosed with a stroke at an age < 50 years old, while ARV-DBP was not associated with stroke regardless of the age when the stroke was diagnosed. Conclusions: ARV-SBP in a very short interval is associated with prior history of stroke in younger than 50 years old. Impaired cerebral vasculatures may affect autoregulation in younger patients with stroke, which possibly manifests as BPV. Longitudinal cohort studies to determine the association between BPV and stroke are required.