Warfarin use and mortality, stroke, and bleeding outcomes in a cohort of elderly patients with non-valvular atrial fibrillation

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Abstract

Aims: To determine exposure to warfarin and the associated outcomes in a population of older patients with non-valvular atrial fibrillation (NVAF). Methods: Cohort study of patients aged 65-89 years admitted to hospital July 2003-December 2008 with newly-diagnosed or pre-existing AF. Outcomes at three years among one-year survivors post-index admission (landmark date) were all-cause mortality, stroke/systemic thromboembolism (stroke/TE) and bleeding. Multivariate Cox models were used to identify factors associated with each outcome. Results: AF was the principal diagnosis for 27.5% of 17,336 index AF admissions. Of 14,634 (84.4%) patients alive at one-year 1,384 (9.5%) died in the following year. Vascular disease (42%) was the most frequent cause of death. Warfarin use, prior to the index admission and/or the 1-year landmark, did not exceed 40%. Compared to non-exposure or discontinuation at the index admission, initiation or persistence with warfarin prior to the landmark date was associated with reduced risk for all-cause mortality, a statistically non-significant reduction in risk for stroke/TE, and an increased risk for bleeding. Higher CHA2DS2-VASc scores were associated with increased risk for each outcome. Conclusions: In a population-based cohort of hospitalised NVAF patients, the initiation and persistent use of warfarin was associated with lower all-cause mortality risk to three years, although reduction in risk for stroke/TE did not reach statistical significance. The apparent under-use of warfarin in this older, high-risk cohort reinforces the opportunity for further reduction in stroke/TE with the uptake of non-vitamin K oral anti-coagulants (NOACs) among those not prescribed, or not persistent with, warfarin.

Original languageEnglish
JournalJOURNAL OF ATRIAL FIBRILLATION
Volume12
Issue number1
Publication statusPublished - 1 Jan 2019

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Warfarin
Atrial Fibrillation
Stroke
Thromboembolism
Hemorrhage
Mortality
Risk Reduction Behavior
Coagulants
Vascular Diseases
Proportional Hazards Models
Population
Survivors
Cause of Death
Cohort Studies

Cite this

@article{f95f161250694ede93b37a467fe38ab6,
title = "Warfarin use and mortality, stroke, and bleeding outcomes in a cohort of elderly patients with non-valvular atrial fibrillation",
abstract = "Aims: To determine exposure to warfarin and the associated outcomes in a population of older patients with non-valvular atrial fibrillation (NVAF). Methods: Cohort study of patients aged 65-89 years admitted to hospital July 2003-December 2008 with newly-diagnosed or pre-existing AF. Outcomes at three years among one-year survivors post-index admission (landmark date) were all-cause mortality, stroke/systemic thromboembolism (stroke/TE) and bleeding. Multivariate Cox models were used to identify factors associated with each outcome. Results: AF was the principal diagnosis for 27.5{\%} of 17,336 index AF admissions. Of 14,634 (84.4{\%}) patients alive at one-year 1,384 (9.5{\%}) died in the following year. Vascular disease (42{\%}) was the most frequent cause of death. Warfarin use, prior to the index admission and/or the 1-year landmark, did not exceed 40{\%}. Compared to non-exposure or discontinuation at the index admission, initiation or persistence with warfarin prior to the landmark date was associated with reduced risk for all-cause mortality, a statistically non-significant reduction in risk for stroke/TE, and an increased risk for bleeding. Higher CHA2DS2-VASc scores were associated with increased risk for each outcome. Conclusions: In a population-based cohort of hospitalised NVAF patients, the initiation and persistent use of warfarin was associated with lower all-cause mortality risk to three years, although reduction in risk for stroke/TE did not reach statistical significance. The apparent under-use of warfarin in this older, high-risk cohort reinforces the opportunity for further reduction in stroke/TE with the uptake of non-vitamin K oral anti-coagulants (NOACs) among those not prescribed, or not persistent with, warfarin.",
keywords = "Atrial Fibrillation, Clinical Outcomes, Landmark Analysis, Linked Data, Population Study, Warfarin",
author = "Bradshaw, {Pamela J.} and Hung Joseph and Knuiman Matthew and Briffa, {Tomas G.} and Nedkoff Lee and Katzenellebogen, {Judith K.} and {Rankin Jamie}, M. and Frank Sanfilippo",
year = "2019",
month = "1",
day = "1",
language = "English",
volume = "12",
journal = "JOURNAL OF ATRIAL FIBRILLATION",
issn = "1941-6911",
publisher = "Cardiofront, Inc.",
number = "1",

}

TY - JOUR

T1 - Warfarin use and mortality, stroke, and bleeding outcomes in a cohort of elderly patients with non-valvular atrial fibrillation

AU - Bradshaw , Pamela J.

AU - Joseph, Hung

AU - Matthew, Knuiman

AU - Briffa , Tomas G.

AU - Lee, Nedkoff

AU - Katzenellebogen , Judith K.

AU - Rankin Jamie, M.

AU - Sanfilippo, Frank

PY - 2019/1/1

Y1 - 2019/1/1

N2 - Aims: To determine exposure to warfarin and the associated outcomes in a population of older patients with non-valvular atrial fibrillation (NVAF). Methods: Cohort study of patients aged 65-89 years admitted to hospital July 2003-December 2008 with newly-diagnosed or pre-existing AF. Outcomes at three years among one-year survivors post-index admission (landmark date) were all-cause mortality, stroke/systemic thromboembolism (stroke/TE) and bleeding. Multivariate Cox models were used to identify factors associated with each outcome. Results: AF was the principal diagnosis for 27.5% of 17,336 index AF admissions. Of 14,634 (84.4%) patients alive at one-year 1,384 (9.5%) died in the following year. Vascular disease (42%) was the most frequent cause of death. Warfarin use, prior to the index admission and/or the 1-year landmark, did not exceed 40%. Compared to non-exposure or discontinuation at the index admission, initiation or persistence with warfarin prior to the landmark date was associated with reduced risk for all-cause mortality, a statistically non-significant reduction in risk for stroke/TE, and an increased risk for bleeding. Higher CHA2DS2-VASc scores were associated with increased risk for each outcome. Conclusions: In a population-based cohort of hospitalised NVAF patients, the initiation and persistent use of warfarin was associated with lower all-cause mortality risk to three years, although reduction in risk for stroke/TE did not reach statistical significance. The apparent under-use of warfarin in this older, high-risk cohort reinforces the opportunity for further reduction in stroke/TE with the uptake of non-vitamin K oral anti-coagulants (NOACs) among those not prescribed, or not persistent with, warfarin.

AB - Aims: To determine exposure to warfarin and the associated outcomes in a population of older patients with non-valvular atrial fibrillation (NVAF). Methods: Cohort study of patients aged 65-89 years admitted to hospital July 2003-December 2008 with newly-diagnosed or pre-existing AF. Outcomes at three years among one-year survivors post-index admission (landmark date) were all-cause mortality, stroke/systemic thromboembolism (stroke/TE) and bleeding. Multivariate Cox models were used to identify factors associated with each outcome. Results: AF was the principal diagnosis for 27.5% of 17,336 index AF admissions. Of 14,634 (84.4%) patients alive at one-year 1,384 (9.5%) died in the following year. Vascular disease (42%) was the most frequent cause of death. Warfarin use, prior to the index admission and/or the 1-year landmark, did not exceed 40%. Compared to non-exposure or discontinuation at the index admission, initiation or persistence with warfarin prior to the landmark date was associated with reduced risk for all-cause mortality, a statistically non-significant reduction in risk for stroke/TE, and an increased risk for bleeding. Higher CHA2DS2-VASc scores were associated with increased risk for each outcome. Conclusions: In a population-based cohort of hospitalised NVAF patients, the initiation and persistent use of warfarin was associated with lower all-cause mortality risk to three years, although reduction in risk for stroke/TE did not reach statistical significance. The apparent under-use of warfarin in this older, high-risk cohort reinforces the opportunity for further reduction in stroke/TE with the uptake of non-vitamin K oral anti-coagulants (NOACs) among those not prescribed, or not persistent with, warfarin.

KW - Atrial Fibrillation

KW - Clinical Outcomes

KW - Landmark Analysis

KW - Linked Data

KW - Population Study

KW - Warfarin

UR - http://www.scopus.com/inward/record.url?scp=85073739202&partnerID=8YFLogxK

M3 - Article

VL - 12

JO - JOURNAL OF ATRIAL FIBRILLATION

JF - JOURNAL OF ATRIAL FIBRILLATION

SN - 1941-6911

IS - 1

ER -