Abstract 11223: Hydrochlorothiazide Use is Independently Associated With a Decreased Risk of New Atrial Fibrillation in Hypertensive Patients With Electrocardiographic Left Ventricular Hypertrophy
Background: High and even upper-normal blood pressure (BP) are predictors of incident atrial fibrillation (AF) and we have recently demonstrated that more aggressive BP control is associated with a lower risk of new AF. Previous study has demonstrated that hydrochlorothiazide (HCTZ) use is independently associated with greater left atrial size reduction in hypertensive patients. However, whether HCTZ use is associated with a lower incidence of AF independent of BP effects is unclear.
Methods: Risk of new-onset AF was examined in relation to in-study HCTZ use in 8704 hypertensive patients with ECG LVH with no history of AF, in sinus rhythm on their baseline ECG, with baseline data on HCTZ use, who were randomly assigned to losartan- or atenolol-based treatment with additional protocol-based use of HCTZ as needed to lower BP.
Results: During 4.7±1.1 years follow-up, new-onset AF was diagnosed in 691 patients (7.9%) and 6,932 (79.6%) were treated with HCTZ at some time. In univariate Cox analysis, in-study HCTZ use, entered as a time-varying covariate, was associated with a 19% lower risk (95% CI 5-32%) of developing AF. After adjusting for other univariate predictors of new AF, including randomized treatment, age, sex, race, diabetes, history of ischemic heart disease, MI or heart failure, prior antihypertensive therapy, baseline serum creatinine, urine albumin/creatinine ratio and a logistic propensity score for HCTZ use entered as standard covariates, and for incident heart failure and in-treatment systolic and diastolic BP, Cornell product left ventricular hypertrophy, heart rate, QRS duration, HDL cholesterol, statin and calcium channel blocker use treated as time-varying covariates, in-study HCTZ use remained associated with a 21% lower risk (95% CI 7-34%) of new AF. Use of HCTZ at any time during the study, entered as a standard covariate, predicted a significantly lower 5-year incidence of AF in Kaplan-Meier analysis (7.5 vs 10.3%, p<0.001) and an identical 21% lower risk of new AF (95% CI 4-35%) in a parallel multivariate Cox analysis.
Conclusions: HCTZ use is associated with a lower risk of developing new-onset AF in hypertensive patients, independent of in-treatment BP, other possible AF risk factors and of the propensity to use HCTZ in this population.
Author Disclosures: P.M. Okin: Research Grant; Significant; Novartis Pharmaceuticals. Consultant/Advisory Board; Significant; Novartis Pharmaceuticals. K. Wachtell: Consultant/Advisory Board; Modest; Merck & co., Inc. S.E. Kjeldsen: Honoraria; Modest; Bayer, MSD, Novartis, Takeda. Consultant/Advisory Board; Modest; Bayer, Serodus, Takeda. Other; Modest; Gyldendal. R.B. Devereux: None.
- © 2014 by American Heart Association, Inc.