Serum digoxin concentration and outcomes in women with heart failure: A bi-directional effect and a possible effect modification by ejection fraction.

Pubmed ID: 16311070

Pubmed Central ID: PMC2708081

Journal: European journal of heart failure

Publication Date: June 1, 2006

Affiliation: Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA. aahmed@uab.edu

MeSH Terms: Humans, Female, Aged, Middle Aged, Chronic Disease, Treatment Outcome, Cause of Death, Cardiotonic Agents, Stroke Volume, Placebos, Digoxin, Cardiac Output, Low

Grants: K23 AG019211, K23 AG019211-03, 1-K23-AG19211-01, K23 AG019211-02

Authors: Aronow WS, Ahmed A, Weaver MT, Aban IB, Fleg JL

Cite As: Ahmed A, Aban IB, Weaver MT, Aronow WS, Fleg JL. Serum digoxin concentration and outcomes in women with heart failure: A bi-directional effect and a possible effect modification by ejection fraction. Eur J Heart Fail 2006 Jun;8(4):409-19. Epub 2005 Nov 28.

Studies:

Abstract

BACKGROUND: The association between serum digoxin concentration (SDC) and outcomes in women with heart failure (HF) has not been well studied. AIMS: To test the hypothesis that the effect of digoxin on outcomes in women with HF is bi-directional and dependent on SDC, as in men, and is modified by ejection fraction (EF). METHODS: We studied 1366 female participants of the Digitalis Investigation Group trial in whom data on SDC (ng/ml) were available. We calculated adjusted odds ratios (AOR) and Bonferroni-adjusted 97.5% confidence intervals (CI) for various outcomes at a median follow up of 41 months, in all women and stratified by EF 35%. RESULTS: Compared with placebo (26.9%), 40.3% with SDC> or =1.2 (AOR=1.80; CI=1.14-2.86; p=0.004) and 26.6% with SDC 0.5-1.1 (AOR=1.05; CI=0.73-1.51; p=0.762) died. Respective rates for HF-hospitalizations were: placebo (32.8%), SDC> or =1.2 (38.0%) and SDC 0.5-1.1 (25.5%). For women with EF<35% (N=677), SDC 0.5-1.1 lowered odds for HF-hospitalizations (AOR=0.63; CI=0.39-1.00; p=0.026) without increasing odds for death (AOR=0.77; CI=0.47-1.26; p=0.233). In women with EF> or =35% (N=689), SDC 0.5-1.1 had a borderline association with death (AOR=1.58; CI=0.92-2.72; p=0.058) but not with HF-hospitalization (AOR=0.95; CI=0.54-1.66; p=0.826). CONCLUSIONS: As in men, in women with HF, digoxin has a bi-directional effect based on SDC, and the beneficial effects were significant only among women with EF<35%.