Is orthostatic hypotension more common in individuals with atrial fibrillation?-Findings from The Irish Longitudinal Study on Ageing (TILDA)

Introduction: atrial fibrillation (AF) and orthostatic hypotension (OH) share common risk factors such as age, hypertension and cardiovascular (CV) disease. The autonomic nervous system (ANS) also plays a role in the pathogenesis of both AF and OH. The aim of this study is to assess whether individuals with AF are more likely to have OH than those without AF. Methods: data from wave 1 of The Irish Longitudinal Study on Ageing were used. Beat-to-beat blood pressure was measured during active stand lasting 110 s. OH, defined as a drop in systolic blood pressure (SBP) >= 20 mmHg or a drop in diastolic blood pressure >= 10 mmHg at 30, 60 and 90 s was assessed. Initial OH (IOH) was assessed as a drop in SBP >= 40 mmHg or a drop in diastolic BP >= 20 mmHg. Results: in total 4,408 participants aged >= 50 had active stand and electrocardiogram data suitable for analysis. AF was identified in 101 of these. Logistic regression found participants with AF were more likely to have OH at 30 (odds ratio (OR) 1.95, 95% confidence interval (CI) 1.24-3.06) and 60 (OR 2.13, 95% CI 1.18-3.87) seconds, and IOH (OR 1.81, 95% CI 1.21-2.70). The association between IOH and OH at 30 s remained significant following adjustment for confounders (age, sex, baseline HR, education, BP, smoking, frailty, beta blocker (BB) use, anti-hypertensive use (excluding BBs) and number of CV conditions). Conclusion: OH is more common in individuals with AF, this may reflect the role of the ANS in both AF and OH.