Effect of hypertension on anticoagulated patients with atrial fibrillation

Abstract

To test the hypothesis that stroke and systemic embolic events (SEE) in the Stroke Prevention using an ORal Thrombin Inhibitor in atrial Fibrillation (SPORTIF) III and V trials were related to blood pressure, and that differences in event rates (stroke and SEE, bleeding) could also be related to the degree of hypertension. A cross-sectional, longitudinal analysis was conducted, using data from the SPORTIF III and V trials. Results showed an increasing rate of stroke and SEE with increasing quartiles of systolic blood pressure (SBP) in AF patients. For the top quartile of SBP compared with the lowest quartile, the hazard ratio (HR) for stroke and SEE was 1.83 (95% confidence intervals [CI]: 1.22-2.74), whereas mortality was lower in the top quartile (HR 0.64; 95% CI: 0.49-0.83). In the combined SPORTIF III and V cohort, the event rate for stroke/SEE increased markedly at mean SBP of > 140 mmHg. There was no relationship between bleeding and quartiles of BP. The proportion of subjects with mean systolic BP > or = 140 mmHg was 35.8% (1220/3407) in SPORTIF III and 20.6% (807/3922) in SPORTIF V (P < 0.0001). Hypertension contributes to increased stroke and SEE in AF. Event rates markedly increase at SBP levels of > or = 140 mmHg. The higher stroke rates observed in SPORTIF III compared with SPORTIF V may be related to the greater proportion of subjects with SBP > or = 140 mmHg during the trial.