Increasing US Emergency Department Visit Rates and Subsequent Hospital Admissions for Atrial Fibrillation from 1993 to 2004

doi:10.1016/j.annemergmed.2007.03.007

Annals of Emergency Medicine

Volume 51, Issue 1, January 2008, Pages 58-65

https://doi.org/10.1016/j.annemergmed.2007.03.007 Get rights and content

Study objective

Atrial fibrillation is a significant public health problem that is becoming increasingly prevalent. The clinical epidemiology of US emergency department (ED) visits for atrial fibrillation is uncertain. This study seeks to describe recent trends in ED visits for atrial fibrillation.

Methods

ED visits with a primary diagnosis of atrial fibrillation were analyzed using data from the US National Hospital Ambulatory Medical Care Survey, 1993 to 2004.

Results

During the 12-year period, there were approximately 2.7 million (95% confidence interval [CI] 2.4 to 3.0 million) ED visits for atrial fibrillation in the United States, and the population-adjusted visit rate increased from 0.6 to 1.2 per 1,000 US population (P for trend=.02). Similarly, the absolute number of visits increased 88%, from 300,000 (95% CI 209,000 to 392,000) in 1993 to 1994 to 564,000 (95% CI 423,000 to 705,000) in 2003 to 2004. Approximately 64% (95% CI 59% to 69%) of these patients were admitted to the hospital, a rate that remained constant throughout the 12-year period (P for trend=.73). Admission rates were significantly lower in the western region of the United States (48%; 95% CI 36% to 60% versus 76%; in the Northeast, 95% CI 68% to 84%). Patient characteristics and ED management did not materially differ by admission status. In a multivariate model, congestive heart failure was the only predictor of admission but accounted for only 14% of admissions.

Conclusion

From 1993 to 2004, the population-adjusted rate of ED visits for atrial fibrillation increased, whereas the proportion admitted to the hospital remained stable. Patient characteristics and ED management were similar regardless of admission status, and there were relatively few predictors of admission.

Introduction

Atrial fibrillation is the most common significant cardiac arrhythmia encountered by physicians, and it is associated with significant morbidity and mortality.1, 2, 3, 4 In the United States, there are an estimated 2.3 million adults with atrial fibrillation, or approximately 0.95% of the population.⁵ Several studies have shown that prevalence increases with age, from 0.1% among those younger than age 55 years to 9% among those age 80 years or older. With the increasing age of the baby boomer population, the prevalence of atrial fibrillation in the United States is expected to increase dramatically. Go et al⁵ projected that the number of patients with atrial fibrillation will increase to more than 5.6 million by 2050. Already, a substantial increase in the number of hospitalizations for atrial fibrillation has been observed, with hospitalizations increasing 2- to 3-fold from 1985 to 1999.⁶ Furthermore, hospitalized patients with acute atrial fibrillation as the primary diagnosis had a mean length of stay of 4 days, resulting in mean hospital charges of approximately $7,000.⁷ Thus, as the prevalence of atrial fibrillation increases with our aging population, the number of hospitalizations and, consequently, the costs of treating patients with atrial fibrillation are expected to continue to increase.

Little is known about the impact of the growing prevalence of atrial fibrillation on emergency departments (EDs) in the United States. Defining ED management and admission patterns will be essential for planning interventions that may safely ease costs and lead to improved outcomes.

In this study, we seek to shed light on recent trends in ED visits for atrial fibrillation by examining the clinical epidemiology of such visits on a national level during a 12-year period, including analysis of visit rates and ED treatments, as well as rates and possible predictors of hospital admission.

Section snippets

Study Design

All data from the ED component of the National Hospital Ambulatory Medical Care Survey (NHAMCS) from 1993 to 2004 were combined for analysis.8, 9 NHAMCS is a 4-stage probability sample of hospital visits. NHAMCS is conducted annually and covers geographic primary sampling units, hospitals within primary sampling units, EDs within hospitals, and patients within EDs.

Setting and Selection of Participants

The setting of the NHAMCS is a random sample of all EDs in noninstitutional general and short-stay hospitals, excluding federal,

Results

From 1993 to 2004, there were approximately 2.7 million (95% CI 2.4 to 3.0 million) ED visits in the United States with a primary diagnosis of atrial fibrillation, estimated from 750 observed ED visits for atrial fibrillation in the NHAMCS sample (Table 1). ED visit rates for atrial fibrillation increased with age, ranging from 0.2 per 1,000 US population for those younger than 50 years to 6.7 per 1,000 US population for those aged 80 years and older. Visits for atrial fibrillation tended to be

Limitations

There are several potential limitations of our study. One limitation is that we considered atrial fibrillation as the reason for an ED visit only if atrial fibrillation was listed as the primary diagnosis on the NHAMCS data collection form. It is possible that some ED visits with atrial fibrillation listed as a secondary or tertiary diagnosis were due mainly to atrial fibrillation, which may have led us to underestimate the total number of ED visits attributable to atrial fibrillation and,

Discussion

The overall prevalence of atrial fibrillation will continue to increase as US baby boomers age.⁵ Already, the number of hospitalizations for atrial fibrillation has increased.⁶ Our study reveals that the expanding public health burden of atrial fibrillation is evident in the ED setting. Both the total number and population-adjusted rate of ED visits for atrial fibrillation have increased significantly during the last decade. Almost two-thirds of those patients were admitted to the hospital,

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Cited by (145)

The effect of serum calcium level on the success of diltiazem treatment: A retrospective cohort study
2023, American Journal of Emergency Medicine
Diltiazem is an antiarrhythmic drug widely used in the treatment of atrial fibrillation (AFib) with rapid ventricular response (RVR). It reveals its effect by blocking L-type calcium channels. Thus, it inhibits the extracellular calcium influx into the cytosol. The relationship between serum calcium level and the efficacy of intravenous (IV) diltiazem used in the treatment of AFib with RVR has not been investigated in vivo. The aim of this study is to investigate the mentioned relationship.
This study was planned as a single-center retrospective study. The data of 349 patients who presented to the emergency department with AFib with RVR and treated with diltiazem were retrospectively analyzed. A patient was considered to have responded to diltiazem treatment if the existing heart rhythm returned to sinus rhythm, or the heart rate decreased below 100 beats/min, or the heart rate decreased >20% provided that it was below 120 beats/min. The ionized calcium levels were recorded. The relationship between serum calcium level and the success of diltiazem treatment was examined.
Fifty five percent of the patients were female. The median age was 75 years. The rate of response to diltiazem treatment was 67.3%. The median of ionized calcium levels in the group which responded to diltiazem treatment (n = 235) was 1.14 mmol/L (IQR: 0.12), and the group which did not respond to diltiazem treatment (n = 114) was 1.11 mmol/L (IQR: 0.12) (p = 0.322). The patients were divided into three groups as low, normal, and high calcium levels according to the calcium reference levels determined by the hospital laboratory. The rate of response to diltiazem treatment was 61.4% in patients with low ionized calcium levels, 76.1% in patients with normal ionized calcium levels, and 40.0% in patients with high ionized calcium levels. The rate of response to diltiazem treatment was higher in patients with normal ionized calcium levels compared to patients with low or high ionized calcium levels (p = 0.004, p = 0.003).
The success rate of diltiazem used in the treatment of AFib with RVR was highest in physiological calcium levels. The current study may provide the clinician with awareness about the consideration of serum ionized calcium levels when choosing drugs in patients with AFib with RVR.
Trends and Inpatient Outcomes of Primary Atrial Fibrillation Hospitalizations with Underlying Iron Deficiency Anemia: An Analysis of The National Inpatient Sample Database from 2004 –2018
2022, Current Problems in Cardiology
Atrial fibrillation (AF) is the most prevalent arrhythmia in the United States. However, studies evaluating the impact of iron deficiency anemia on AF outcomes are limited. Therefore, we aimed to evaluate the association of iron deficiency anemia (IDA) on clinical outcomes in patients hospitalized with AF. A retrospective analysis of adult hospital discharges from the National Inpatient Sample (NIS) between 2004 and 2018 was conducted. Multivariable logistic regression was used to assess the association of IDA and other clinical outcomes ie inpatient mortality, acute myocardial infarction, cardiogenic shock, acute kidney injury, vasopressors use, length of stay, and other resource utilization. These models were adjusted for patient and hospital-level characteristics. A total of 5,975,241 weighted primary AF hospitalizations were identified. Out of these, 152,059 (2.5%) had diagnosis of IDA. After adjustment of variables, admissions with IDA were associated with higher rates of acute myocardial infarction (adjusted odds ratio [aOR] = 1.10, 95% CI 1.01–1.19 P = 0.026), use of vasopressors (aOR = 1.30, CI 1.27–1.32, P <0.001), invasive mechanical ventilation (aOR = 1.26, CI 1.14–1.40 P <0.001) and acute kidney injury (aOR = 1.72, CI 1.66–1.79 P <0.001). There was no significant difference in all-cause mortality (aOR = 0.97, CI 0.87–1.07, P = 0.513), cardiogenic shock, in-hospital cardiac arrest or use of mechanical circulatory support. Adjusted mortality in patients with AF and IDA decreased from 1.09% to 0.54% from 2004 to2018 (P -trend < 0.001). Among hospitalized patients with AF, our study did not show any difference in all-cause mortality between those with and without IDA.
Rhythm Control Vs Rate Control in a Contemporary Ambulatory Atrial Fibrillation Cohort: Post Hoc Analysis of the IMPACT-AF Trial
2022, CJC Open
We examined the characteristics and outcomes in a contemporary ambulatory population of patients with atrial fibrillation (AF), comparing rate control with rhythm control.
This is a post hoc analysis of a cluster-randomized trial (Integrated Management Program Advancing Community Treatment of Atrial Fibrillation [IMPACT-AF]) in ambulatory AF patients from 2016 to 2018, which compared use of a clinical decision support tool for general practitioners to usual care. This analysis compared patients managed with rate vs rhythm control, at entry into the study. Outcomes included AF-related emergency department (ED) visits, unplanned cardiovascular hospitalizations, and bleeding events at 12 months.
A total of 870 patients were included in this analysis, 99 (11.4%) in the rhythm-control group, and 40% women. In the rhythm-control group, the mean age was younger (70 ± 11.4 vs 72.7 ± 9.5 years, P = 0.03), a higher number were paroxysmal (80% vs 43%, P < 0.001), and CHADS₂ scores were lower. The rate of AF-related ED visits was higher in the rhythm-control group (17.2 vs 7.3%, P = 0.003), and repeat visits (rate ratio 3.03, 95% confidence interval [1.99-4.52], P < 0.001). The number of repeat ED visits was independently associated with female sex and being in the rhythm-control group.
Both rate- and rhythm-control patients have recurrent ED visits, with a higher rate in patients treated with rhythm control. These findings are observational, but taken in the context of current guidelines could help develop further therapies aimed at improving symptom burden in both rhythm- and rate-control patients to broadly improve healthcare utilization in the AF population.
Nous avons examiné les caractéristiques et le devenir de patients ambulatoires contemporains atteints de fibrillation auriculaire (FA) dans le cadre d’une comparaison entre la maîtrise de la fréquence cardiaque et la maîtrise du rythme cardiaque.
Nous avons effectué une analyse a posteriori d’un essai à répartition aléatoire par grappes (Integrated Management Program Advancing Community Treatment of Atrial Fibrillation [IMPACT-AF]) mené de 2016 à 2018 chez des patients ambulatoires atteints de FA en vue de comparer un outil d’aide à la décision clinique destiné aux omnipraticiens avec les soins habituels. Notre analyse a permis d’établir une comparaison entre les patients pris en charge par une maîtrise de la fréquence cardiaque et ceux pris en charge par une maîtrise du rythme cardiaque lors de leur inscription à l’essai. Les paramètres d’évaluation comprenaient les consultations aux urgences liées à la FA, les hospitalisations imprévues ayant des causes cardiovasculaires et les épisodes hémorragiques à 12 mois.
Au total, 870 patients ont été inclus dans cette analyse; 99 (11,4 %) faisaient partie du groupe pris en charge par une maîtrise du rythme cardiaque, et 40 % étaient de femmes. Dans le groupe pris en charge par une maîtrise du rythme cardiaque, l’âge moyen était moindre (70 ± 11,4 ans vs 72,7 ± 9,5 ans, P = 0,03), un plus grand nombre de patients présentaient une FA paroxystique (80 % vs 43 %, P < 0,001) et les scores CHADS₂ étaient moins élevés. Le taux de consultations aux urgences liées à la FA était plus élevé dans le groupe pris en charge par une maîtrise du rythme cardiaque (17,2 vs 7,3 %, P = 0,003) tout comme le taux de consultations répétées aux urgences (rapport des taux de 3,03, intervalle de confiance à 95 % de 1,99 à 4,52, P < 0,001). Le nombre de consultations répétées aux urgences était indépendamment associé au sexe féminin et à l’inclusion dans le groupe pris en charge par une maîtrise du rythme cardiaque.
Des consultations répétées aux urgences ont été notées tant chez les patients pris en charge par une maîtrise de la fréquence cardiaque que chez ceux pris en charge par une maîtrise du rythme cardiaque quoique plus fréquemment chez ces derniers. Nos constats sont de type observationnel. Néanmoins, dans le contexte des lignes directrices actuelles, ils pourraient contribuer à la mise au point d’autres traitements visant à atténuer le fardeau des symptômes tant chez les patients pris en charge par une maîtrise du rythme cardiaque que chez ceux pris en charge par une maîtrise de la fréquence cardiaque et ainsi permettre globalement une meilleure utilisation des soins de santé chez les patients atteints de FA.
Characteristics of patients presenting to emergency department for primary atrial fibrillation or flutter at an academic medical center
2021, Indian Heart Journal
In the United States, atrial fibrillation (AF) accounts for over 400,000 hospitalizations annually. Emergency Department (ED) physicians have few resources available to guide AF/AFL (atrial flutter) patient triage, and the majority of these patients are subsequently admitted. Our aim is to describe the characteristics and disposition of AF/AFL patients presenting to the University of North Carolina (UNC) ED with the goal of developing a protocol to prevent unnecessary hospitalizations.
We performed a retrospective electronic medical chart review of AF/AFL patients presenting to the UNC ED over a 15-month period from January 2015 to March 2016. Demographic and ED visit variables were collected. Additionally, patients were designated as either having primary or secondary AF/AFL where primary AF/AFL patients were those in whom AF/AFL was the primary reason for ED presentation. These primary AF/AFL patients were categorized by AF symptom severity score according to the Canadian Cardiovascular Society Severity of Atrial Fibrillation (CCS-SAF) Scale.
A total of 935 patients presented to the ED during the study period with 202 (21.5%) having primary AF/AFL. Of the primary AF/AFL patients, 189 (93.6%) had mild-moderate symptom severity (CCS-SAF ≤ 3). The majority of primary AF/AFL patients were hemodynamically stable, with a mean (SD) SBP of 123.8 (21.3), DBP of 76.6 (14.1), and ventricular rate of 93 (21.9). Patients with secondary AF/AFL were older 76 (13.1), p < 0.001 with a longer mean length of stay 6.1 (7.7), p = 0.31. Despite their mild-moderate symptom severity and hemodynamic stability, nearly 2/3 of primary AF/AFL patients were admitted.
Developing a protocol to triage and discharge hemodynamically stable AF/AFL patients without severe AF/AFL symptoms to a dedicated AF/AFL clinic may help to conserve healthcare resources and potentially deliver more effective care.
Evaluation of metoprolol versus diltiazem for rate control of atrial fibrillation in the emergency department
2021, American Journal of Emergency Medicine
The purpose of this study was to compare the effectiveness and safety of the metoprolol and diltiazem administration in the Emergency Department (ED) for rate control of supraventricular tachycardia.
This was a retrospective cohort study of adult patients who presented to the ED with ventricular rates ≥120 beats per minute (bpm) and who received bolus doses of either intravenous metoprolol or intravenous diltiazem. The primary outcome was achievement of rate control, defined as heart rate < 110 bpm, at two hours after administration of the last bolus dose of metoprolol or diltiazem. Safety outcomes included occurrence of hypotension, defined as systolic blood pressure < 90 mmHg or diastolic blood pressure < 60 mmHg, and bradycardia, defined as heart rate < 60 bpm.
There were 166 patients receiving metoprolol and 183 patients receiving diltiazem included in the study. The primary outcome, rate control at two hours after the last bolus dose of metoprolol or diltiazem was similar between the two groups (45.8% vs 42.6%, p = 0.590, respectively). The percentage of patients achieving rate control was also similar (47.0% vs 41.6%, p = 0.333) at one hour. At 0.5 h HR had a significantly greater numerical (diltiazem: 29.3 ± 23.1 bpm vs metoprolol: 21.8 ± 18.9 bpm, p = 0.012) and percent decrease (21.1% vs 15.94%, p = 0.014) in the diltiazem group compared to metoprolol. There was no significant difference in occurrence of bradycardia in the two groups (diltiazem: 3.83% vs metoprolol: 1.2%, p = 0.179). More patients in the diltiazem group compared to the metoprolol group experienced hypotension (39.3% vs 23.5%, p = 0.002). The difference in systolic hypotension events was not significantly different (9.29% vs 5.42%, p = 0.221), while the difference in diastolic hypotension events was significantly different (37.7% vs 22.3%, p = 0.002).
There was no difference in acute rate control effectiveness two hours after the last bolus dose of diltiazem and metoprolol for supraventricular tachycardias. There was a significantly higher occurrence of hypotension in the diltiazem group which was driven by higher rates of diastolic blood pressures less than 60 mmHg.
Weight-based versus non-weight-based diltiazem dosing in the setting of atrial fibrillation with rapid ventricular response
2020, American Journal of Emergency Medicine
There is conflicting evidence to support the superiority of weight-based (WB) dosing of intravenous (IV) diltiazem over non-weight-based (NWB) dosing strategies in the management of atrial fibrillation (AFib) with rapid ventricular response (RVR).
A retrospective review evaluated patients presenting to the emergency department (ED) in AFib with RVR and receiving IV diltiazem from 2015 to 2018. Those receiving a NWB dose were compared with those receiving a WB dose based on actual body weight (ABW). Secondary analyses evaluated safety profiles of the regimens and compared response in groups defined by ABW or ideal body weight (IBW).
A total of 371 patients were included in the analysis. No significant difference was observed in achieving a therapeutic response (66.5% vs. 73.1%, p = 0.18) or adverse events between the groups. Patients receiving a WB dose were significantly more likely to have a HR < 100 bpm than those receiving a NWB dose (40.9% vs. 53.5%, p = 0.01). When groups were defined by IBW, WB dosing was associated with a significantly higher incidence of achieving a therapeutic response (62.7% vs. 74.3%, p = 0.02).
In patients presenting with AF with RVR, there was no significant difference in achieving a therapeutic response between the two strategies. A WB dosing approach did result in a greater proportion of patients with a HR < 100 bpm. The utilization of IBW for WB dosing may result in an increased achievement of a therapeutic response.

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: Supervising editor: W. Brian Gibler, MD

: Author contributions: AJM, PTE, and CAC designed the study. AJM was primarily responsible for article preparation, and all authors contributed substantially to its revision. AJP undertook data collection and statistical analyses. PTE and CAC obtained funding. AJM takes responsibility for the paper as a whole.

: Funding and support: By Annals policy, all authors are required to disclose any and all commercial, financial, and other relationships in any way related to the subject of this article, that may create any potential conflict of interest. See the Manuscript Submission Agreement in this issue for examples of specific conflicts covered by this statment. The project was supported in part by the Emergency Medicine Foundation Center of Excellence Award (Dallas, TX) to Dr. Camargo and by grants from the Smith Family Foundation (Boston, MA) and the National Institutes of Health (Bethesda, MD) to Dr. Ellinor (HL-71632). None of the authors have any conflicts of interest to declare.

: Publication dates: Available online April 27, 2007.

: Reprints not available from the authors.

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Cardiology/original researchIncreasing US Emergency Department Visit Rates and Subsequent Hospital Admissions for Atrial Fibrillation from 1993 to 2004

Study objective

Methods

Results

Conclusion

Introduction

Section snippets

Study Design

Setting and Selection of Participants

Results

Limitations

Discussion

J Am Coll Cardiol

Am J Cardiol

Am J Cardiol

Lancet

J Am Coll Cardiol

Am J Cardiol

Ann Emerg Med

Ann Emerg Med

Ann Emerg Med

Atrial fibrillation as an independent risk factor for stroke: the Framingham Study

Stroke

Independent risk factors for atrial fibrillation in a population-based cohortThe Framingham Heart Study

JAMA

Impact of atrial fibrillation on the risk of death: the Framingham Heart Study

Circulation

Cardiology/original research
Increasing US Emergency Department Visit Rates and Subsequent Hospital Admissions for Atrial Fibrillation from 1993 to 2004