Chronic obstructive pulmonary disease predicts higher incidence and in hospital mortality for atrial fibrillation. An observational study using hospital discharge data in Spain (2004–2013)

Risk factors for tachycardia-induced cardiomyopathy due to atrial fibrillation

BACKGROUND

Tachycardia-induced cardiomyopathy (TIC) is a reversible cardiomyopathy with ventricular dysfunction caused by tachyarrhythmias. Notably, atrial fibrillation (AF) is the most common causal arrhythmia leading to TIC. However, the risk factors for the development of TIC due to AF remain unclear. This study aimed to identify the associated factors of TIC due to AF.

METHODS

Persistent AF patients with heart rate (HR) ≥100 beats per minute who underwent initial catheter ablation were enrolled in this study. TIC was diagnosed as left ventricular ejection fraction (LVEF) < 50% during AF rhythm, which was recovered after the restoration of sinus rhythm. Non-TIC was defined as LVEF ≥ 50% despite AF rhythm. The patient backgrounds were compared between the TIC group and the non-TIC group to reveal the contributing factors of TIC.

RESULTS

The TIC group comprised 57 patients, while the non-TIC group consisted of 101 patients. The TIC group was younger than the non-TIC group (median 64 vs. 70, p = 0.006). Male sex was more frequent in the TIC group than the non-TIC group (82.5% vs. 58.4%, p = 0.003). HR was higher in the TIC group than in the non-TIC group (median 130 bpm vs. 111 bpm, p < 0.001). The number of smokers was significantly higher in the TIC group than in the non-TIC group (p < 0.001). Multivariable analysis demonstrated that higher HR (odds ratio [OR]: 1.74; 95% confidence interval [CI]: 1.37-2.21; p < 0.001) and current smokers (OR: 5.27; 95% CI: 1.60-17.4; p = 0.006) were the independent factors leading to TIC.

CONCLUSION

Higher HR and current smokers were independent risk factors for the development of TIC due to AF.

Detrimental Impact of Atrial Fibrillation among Patients Hospitalized for Acute Exacerbation of COPD: Results of a Population-Based Study in Spain from 2016 to 2021

Background/Objectives: To analyze changes in the prevalence of atrial fibrillation (AF) in patients hospitalized for acute exacerbation of chronic obstructive pulmonary disease (AE-COPD); to evaluate hospital outcomes according to AF status, assessing sex differences; to identify factors associated with AF presence; and to analyze variables associated with in-hospital mortality (IHM) in AE-COPD patients with AF. Methods: We used data from the Registry of Specialized Care Activity-Basic Minimum Data Set (RAE-CMBD) to select patients aged ≥40 years with COPD in Spain (2016-2021). We stratified the study population according to AF presence and sex. The propensity score matching (PSM) methodology was employed to create comparable groups based on age, admission year, and comorbidities at the time of hospitalization. Results: We identified 399,196 hospitalizations that met the inclusion criteria. Among them, 20.58% had AF. The prevalence of AF rose from 2016 to 2021 (18.26% to 20.95%), though the increase was only significant in men. The median length of hospital stay (LOHS) and IHM were significantly higher in patients with AF than in those without AF. After PSM, IHM remained significantly higher for man and women with AF. Older age, male sex, and several comorbidities were factors associated with AF. Additionally, older age, male sex, different comorbidities including COVID-19, hospitalization in the year 2020, mechanical ventilation, and intensive care unit (ICU) admission were associated with higher IHM in patients with AE-COPD and AF. Conclusions: AF prevalence was high in patients hospitalized for AE-COPD, was higher in men than in women, and increased over time. AF presence was associated with worse outcomes. The variables associated with IHM in hospitalized AE-COPD patients with AF were older age, male sex, different comorbidities including COVID-19 presence, hospitalization in the year 2020, need of mechanical ventilation, and ICU admission.

Risk of Death and Cardiovascular Events in Asian Patients With Atrial Fibrillation and Chronic Obstructive Pulmonary Disease: A Report From the Prospective APHRS Registry

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with an increased risk of adverse events in patients with atrial fibrillation (AF); however, few data are available on this topic in Asian populations.

METHODS AND RESULTS

Prospective observational study conducted on patients with AF enrolled in the Asia-Pacific Heart Rhythm Society (APHRS) AF Registry. The diagnosis of COPD was based on data reported in the case report form by the investigators. Cox-regression models were used to assess the 1-year risk of a primary composite outcome of all-cause death, thromboembolic events, acute coronary syndrome, and heart failure. Analysis on single outcomes and cardiovascular death was also performed. Interaction analysis was used to assess the risk of composite outcome and all-cause death in different subgroups. The study included 4094 patients with AF (mean±SD age 68.5±12 years, 34.6% female), of whom 112 (2.7%) had COPD. Patients with COPD showed a higher incidence of the primary composite outcome (25.1% versus 6.3%, P<0.001), all-cause death (14.9% versus 2.6%, P<0.001), cardiovascular death (2.0% versus 0.6%, P<0.001), and heart failure (8.3% versus 6.0%, P<0.001). On multiple Cox-regression analysis, COPD was associated with a higher risk of the primary composite outcome (hazard ratio [HR], 3.17 [95% CI, 2.05-4.90]), all-cause death (HR, 3.59 [95% CI, 2.04-6.30]), and heart failure (HR, 3.32 [95% CI, 1.56-7.03]); no statistically significant differences were found for other outcomes. The association between COPD and mortality was significantly modified by the use of beta blockers (Pint=0.018).

CONCLUSIONS

In Asian patients with AF, COPD is associated with worse prognosis. In patients with AF and COPD, the use of beta blockers was associated with a lower mortality.

REGISTRATION INFORMATION

clinicaltrials.gov Identifier: NCT04807049.

Spirometry in atrial fibrillation: what's the catch?

INTRODUCTION

People with COPD rarely have COPD alone, and the commonest co-morbidities occurring with COPD are cardiovascular. Whilst multiple studies have explored the association between major cardiovascular events and COPD, less attention has been paid to arrhythmias, specifically atrial fibrillation (AF). AF and COPD frequently occur together, posing challenges in diagnosis and management. In this review, we describe the relationship between AF and COPD epidemiologically and physiologically, demonstrating the role of spirometry as a diagnostic and disease management tool.

AREAS COVERED

We provide epidemiological evidence that COPD and AF are independent risk factors for one another, that either disease is highly prevalent amongst people with the other, and that they have shared risk factors; all of which contribute to adverse prognostic. We elucidated common pathophysiological mechanisms implicated in AF-COPD. We ultimately present the epidemiological and physiological evidence with a view to highlight specific areas where we feel spirometry is of value in the management of AF-COPD.

EXPERT OPINION

AF and COPD commonly co-occur, there is often diagnostic delay, increased risk of reduced cardioversion success, and missed opportunity to intervene to reduce stroke risk. Greater awareness and timelier diagnosis and guideline directed management may improve outcomes for people with both diseases.

Cardioselective versus Non-Cardioselective Beta-Blockers and Outcomes in Patients with Atrial Fibrillation and Chronic Obstructive Pulmonary Disease

Background: Atrial fibrillation (AF) and chronic obstructive pulmonary disease (COPD) have been independently associated with increased mortality; however, there is no evidence regarding beta-blocker cardioselectivity and long-term outcomes in patients with AF and concurrent COPD. Methods: This post hoc analysis of the MISOAC-AF randomized trial (NCT02941978) included patients hospitalized with comorbid AF. At discharge, all patients were classified according to the presence of COPD; patients with COPD on beta-blockers were classified according to beta-blocker cardioselectivity. Adjusted hazard ratios (aHRs) were calculated by using multivariable Cox regression models. The primary outcome was all-cause mortality, and the secondary outcomes were cardiovascular mortality and hospitalizations. Results: Of 1103 patients with AF, 145 (13%) had comorbid COPD. Comorbid COPD was associated with an increased risk of all-cause (aHR, 1.33; 95% confidence interval (CI), 1.02 to 1.73) and cardiovascular mortality (aHR 1.47; 95% CI, 1.10 to 1.99), but not with increased risk of hospitalizations (aHR 1.10; 95% CI, 0.82 to 1.48). The use of cardioselective versus non-cardioselective beta-blockers was associated with similar all-cause mortality (aHR 1.10; 95% CI, 0.63 to 1.94), cardiovascular mortality (aHR 1.33; 95% CI, 0.71 to 2.51), and hospitalizations (aHR 1.65; 95% CI 0.80 to 3.38). Conclusions: In recently hospitalized patients with AF, the presence of COPD was independently associated with increased risk of all-cause and cardiovascular mortality. No difference between cardioselective and non-cardioselective beta-blockers, regarding clinical outcomes, was identified.

A systematic literature review and meta-analysis on the impact of COPD on atrial fibrillation patient outcome

BACKGROUND

COPD is often accompanied by extra-pulmonary manifestations such as thrombo-embolic and hemorrhagic events, the disease is linked with atrial fibrillation (AF).

OBJECTIVE

The objective of the current review was to assess the impact of chronic obstructive pulmonary disease (COPD) on outcomes of atrial fibrillation (AF).

METHODS

PubMed, Scopus, Embase, and Web of Science databases were searched for studies comparing overall mortality, cardiovascular death, and other outcomes for AF patients with and without COPD. The data retrieved were subjected to both qualitative and quantitative analyses. The hazard ratios (HR) obtained for mortality in presence of COPD were pooled to meta-analyze using generic inverse variance function of RevMan 5.3 software. The association of various risk factors and HRs were pooled with 95% confidence interval (CI). The quality of the included studies was assessed using Newcastle Ottawa scale (NOS).

RESULTS

The hazard ratios (HR) were calculated with 95% confidence intervals (CIs). A total of seven studies were included. The pooled HR for the impact of COPD on overall mortality and cardiovascular mortality in AF patients was found to be 1.70 (95% CI: 1.47, 1.97; p<0.0001) and 1.80 (95% CI: 1.29, 2.52; p = 0.0005), respectively. Hemorrhagic events were significantly higher in AF patients with COPD (Odds ratio (OR): 1.84; 95% CI: 1.58, 2.14; p<0.00001).

CONCLUSION

COPD has a deleterious impact on AF progression in terms of overall mortality, cardiovascular death, stroke and hemorrhagic complications.

Prevalence, management and impact of chronic obstructive pulmonary disease in atrial fibrillation: a systematic review and meta-analysis of 4,200,000 patients

AIM

Prevalence of chronic obstructive pulmonary disease (COPD) in atrial fibrillation (AF) patients is unclear, and its association with adverse outcomes is often overlooked. Our aim was to estimate the prevalence of COPD, its impact on clinical management and outcomes in patients with AF, and the impact of beta-blockers (BBs) on outcomes in patients with COPD.

METHODS AND RESULTS

A systematic review and meta-analysis was conducted according to international guidelines. All studies reporting the prevalence of COPD in AF patients were included. Data on comorbidities, BBs and oral anticoagulant prescription, and outcomes (all-cause death, cardiovascular (CV) death, ischaemic stroke, major bleeding) were compared according to COPD and BB status. Among 46 studies, pooled prevalence of COPD was 13% [95% confidence intervals (CI) 10-16%, 95% prediction interval 2-47%]. COPD was associated with higher prevalence of comorbidities, higher CHA2DS2-VASc score and lower BB prescription [odds ratio (OR) 0.77, 95% CI 0.61-0.98]. COPD was associated with higher risk of all-cause death (OR 2.22, 95% CI 1.93-2.55), CV death (OR 1.84, 95% CI 1.39-2.43), and major bleeding (OR 1.45, 95% CI 1.17-1.80); no significant differences in outcomes were observed according to BB use in AF patients with COPD.

CONCLUSION

COPD is common in AF, being found in 13% of patients, and is associated with increased burden of comorbidities, differential management, and worse outcomes, with more than a two-fold higher risk of all-cause death and increased risk of CV death and major bleeding. Therapy with BBs does not increase the risk of adverse outcomes in patients with AF and COPD.

Chronic obstructive pulmonary disease and atrial fibrillation: an interdisciplinary perspective

Chronic obstructive pulmonary disease (COPD) is highly prevalent among patients with atrial fibrillation (AF), shares common risk factors, and adds to the overall morbidity and mortality in this population. Additionally, it may promote AF and impair treatment efficacy. The prevalence of COPD in AF patients is high and is estimated to be ∼25%. Diagnosis and treatment of COPD in AF patients requires a close interdisciplinary collaboration between the electrophysiologist/cardiologist and pulmonologist. Differential diagnosis may be challenging, especially in elderly and smoking patients complaining of unspecific symptoms such as dyspnoea and fatigue. Routine evaluation of lung function and determination of natriuretic peptides and echocardiography may be reasonable to detect COPD and heart failure as contributing causes of dyspnoea. Acute exacerbation of COPD transiently increases AF risk due to hypoxia-mediated mechanisms, inflammation, increased use of beta-2 agonists, and autonomic changes. Observational data suggest that COPD promotes AF progression, increases AF recurrence after cardioversion, and reduces the efficacy of catheter-based antiarrhythmic therapy. However, it remains unclear whether treatment of COPD improves AF outcomes and which metric should be used to determine COPD severity and guide treatment in AF patients. Data from non-randomized studies suggest that COPD is associated with increased AF recurrence after electrical cardioversion and catheter ablation. Future prospective cohort studies in AF patients are needed to confirm the relationship between COPD and AF, the benefits of treatment of either COPD or AF in this population, and to clarify the need and cost-effectiveness of routine COPD screening.

Risk factors for new-onset atrial fibrillation in patients with chronic obstructive pulmonary disease: a systematic review and meta-analysis

BACKGROUND

New-onset atrial fibrillation (AF) in patients with chronic obstructive pulmonary disease (COPD) is associated with an accelerated decline in lung function, and a significant increase in mortality rate. A deeper understanding of the risk factors for new-onset AF during COPD will provide insights into the relationship between COPD and AF and guide clinical practice. This systematic review and meta-analysis is designed to identify risk factors for new-onset AF in patients with COPD, and to formulate recommendations for preventing AF in COPD patients that will assist clinical decision making.

METHODS

PubMed, Embase, Web of Science and Cochrane Library databases were searched for studies, which reported the results of potential risk factors for new-onset AF in COPD patients.

RESULTS

Twenty studies involving 8,072,043 participants were included. Fifty factors were examined as potential risk factors for new-onset AF during COPD. Risk factors were grouped according to demographics, comorbid conditions, and COPD- and cardiovascular-related factors. In quantitative analysis, cardiovascular- and demographic-related factors with a greater than 50% increase in the odds of new-onset AF included age (over 65 years and over 75 years), acute care encounter, coronary artery disease, heart failure and congestive heart failure. Only one factor is related to the reduction of odds by more than 33.3%, which is black race (vs white). In qualitative analysis, the comparison of the risk factors was conducted between COPD-associated AF and non-COPD-associated AF. Cardiovascular-related factors for non-COPD-associated AF were also considered as risk factors for new-onset AF during COPD; however, the influence tended to be stronger during COPD. In addition, comorbid factors identified in non-COPD-associated AF were not associated with an increased risk of AF during COPD.

CONCLUSIONS

New-onset AF in COPD has significant demographic characteristics. Older age (over 65 years), males and white race are at higher risk of developing AF. COPD patients with a history of cardiovascular disease should be carefully monitored for new-onset of AF, and appropriate preventive measures should be implemented. Even patients with mild COPD are at high risk of new-onset AF. This study shows that risk factors for new-onset AF during COPD are mainly those associated with the cardiovascular-related event and are not synonymous with comorbid factors for non-COPD-associated AF. The pathogenesis of COPD-associated AF may be predominantly related to the cardiac dysfunction caused by the chronic duration of COPD, which increases the risk of cardiovascular-related factors and further increases the risk of AF during COPD.

PROSPERO REGISTRATION NUMBER

CRD42019137758.

Trends, characteristics, in-hospital outcomes and mortality in surgical mitral valve replacement among patients with and without COPD in Spain (2001-2015)

PURPOSE

We examined trends, characteristics and in-hospital outcomes in mechanical and bioprosthetic surgical mitral valve replacement (SMVR) among patients with and without chronic obstructive pulmonary disease (COPD) in Spain from 2001 to 2015. We also identified factors associated with in-hospital mortality (IHM) in both groups of patients according to the implanted valve type.

METHODS

We analyzed data from the Spanish National Hospital Discharge Database for patients aged 40 years or over. We selected admissions of patients whose medical procedures included SMVR. We grouped hospitalizations by COPD status.

RESULTS

Over 43,024 patients identified, 83.63% underwent mechanical mitral valve replacement and 16.37% bioprosthetic valve (6.71% and 7.78% with COPD, respectively). The incidence of SMVR decreased for mechanical valves and increased for bioprosthetic valves over time in both groups of patients. The incidence of SMVR admissions was lower among COPD patients than in those without COPD, both for mechanical and bioprosthetic valves. IHM decreased significantly over time, regardless of the type of valve, in both groups of patients. COPD was associated with a significant increase in IHM, but only among patients who underwent bioprosthetic SMVR (OR 1.32, 95% CI 1.01-1.73).

CONCLUSIONS

The incidence of mechanical SMVR decreased while that of bioprosthetic SMVR increased over time in both groups of patients. COPD patients were less surgically operated than non-COPD patients for both valve types. In COPD patients, bioprosthetic SMVR was proportionally more used than mechanical SMVR. Mortality decreased over time for both valve types in patients with and without COPD. COPD increased in-hospital mortality among patients undergoing a biological SMVR.

Meta-analysis of risk factors and complications associated with atrial fibrillation after oesophagectomy

Background

Oesophagectomy is associated with high morbidity and mortality rates. New-onset atrial fibrillation (AF) is a frequent complication following oesophagectomy. Several studies have explored whether new-onset AF is associated with adverse events after oesophagectomy.

Methods

This review was performed according to PRISMA guidelines. Eligible studies were identified through a search of PubMed, Scopus and Cochrane CENTRAL databases up to 25 November 2018. A meta-analysis was conducted with the use of random-effects modelling. The I2 statistic was used to assess for heterogeneity.

Results

In total, 53 studies including 9087 patients were eligible for analysis. The overall incidence of postoperative AF was 16·5 per cent. Coronary artery disease and hypertension were associated with AF, whereas diabetes, smoking and chronic obstructive pulmonary disease were not. Patients with AF had a significantly higher risk of overall postoperative adverse events than those without fibrillation (odds ratio (OR) 5·50, 95 per cent c.i. 3·51 to 8·30), including 30-day mortality (OR 2·49, 1·70 to 3·64), anastomotic leak (OR 2·65, 1·53 to 4·59) and pneumonia (OR 3·42, 2·39 to 4·90).

Conclusion

Postoperative AF is frequently observed in patients undergoing oesophagectomy for cancer. It is associated with an increased risk of death and postoperative complications.

Sex-related risks of recurrence of atrial fibrillation after ablation: Insights from the Guangzhou Atrial Fibrillation Ablation Registry

BACKGROUND

Female sex has been linked with worse prognosis in patients with atrial fibrillation (AF). Clinical risk stratification of women with AF may help decision-making before catheter ablation (CA).

AIM

To evaluate arrhythmia outcomes and the predictive value of clinical scores for arrhythmia recurrence in a large cohort of Chinese patients with AF undergoing CA.

METHODS

A total 1410 of patients (68.1% men) who underwent AF ablation with scheduled follow-up were analysed retrospectively. Baseline characteristics and ablation outcome were compared between men and women. The predictive values of risk scoring systems for AF recurrence were assessed in women.

RESULTS

Recurrence, early recurrence and complications after CA were similar in women and men over similar follow-up periods (20.7±8.0 vs 20.7±9.1 months; P>0.05). Compared with men, women with AF recurrence were older and had a larger left atrial diameter (LAD), less paroxysmal AF, lower left ventricular ejection fraction, lower estimated glomerular filtration rate (eGFR) and higher serum concentrations of B-type natriuretic peptide (BNP) and C-reactive protein (CRP) (all P<0.01). Multivariable analysis showed that age, non-paroxysmal AF, body mass index, coronary artery disease, LAD, early recurrence, eGFR, BNP and CRP were independent risk factors with sex differences (all P<0.05) in the whole cohort. In women, only non-paroxysmal AF, early recurrence, BNP, CRP (all P<0.01) and history of stroke/transient ischaemic attack (P=0.016) were independent risk factors. Of the clinical scoring systems tested, MB-LATER, APPLE, CAAP-AF and BASE-AF₂ scores (C-indexes 0.73, 0.72, 0.68 and 0.72, respectively; all P<0.01) had a modest predictive value for AF recurrence after CA in women.

CONCLUSIONS

CA for AF has similar recurrence risks in women and men, but there are sex differences in the clinical characteristics and risk factors associated with AF recurrence.

In-hospital mortality of patients with atrial arrhythmias: insights from the German-wide Helios hospital network of 161 502 patients and 34 025 arrhythmia-related procedures

Aims

Atrial fibrillation (AFib) and atrial flutter (AFlut) are common arrhythmias with increased use of invasive procedures. A steady re-evaluation of relevant safety endpoints is recommended and both quality management and pay-for-performance programs are evolving. Therefore, the aims of this study were (i) to investigate and report overall in-hospital mortality and mortality of invasive arrhythmia-related procedures and (ii) to identify mortality predictors in a German-wide hospital network.

Methods and results

Administrative data provided by 78 Helios hospitals between 2010 and 2017 were examined using International Statistical Classification of Diseases and Related Health Problems- and Operations and Procedures-codes to identify patients with AFib or AFlut as main discharge diagnosis or secondary diagnosis combined with invasive arrhythmia-related interventions. In 161 502 patients, in-hospital mortality was 0.6% with a significant decrease from 0.75% to 0.5% (P < 0.01) during the observational period. In multivariable analysis, age [odds ratio (OR) 2.69, 95% confidence interval (CI) 2.36-3.05; P < 0.01], high centre volume (OR 0.57, 95% CI 0.50-0.65; P < 0.01), emergency hospital admission (OR 1.57, 95% CI 1.38-1.79; P < 0.01), and Charlson Comorbidity Index (CCI, OR 4.95, 95% CI 4.50-5.44; P < 0.01) were found as independent predictors of in-hospital mortality. Mortality rates were 0.05% for left atrial catheter ablation (CA, n = 21 744), 0.3% for right atrial CA (n = 9972), and 0.56% for implantation of a left atrial appendage occluder (n = 2309), respectively.

Conclusion

We analysed for the first time in-hospital mortality rates of patients with atrial arrhythmias in a German-wide, multi-centre administrative dataset. This allows feasible, comparable, and up-to-date performance measurement of clinically important endpoints in a real-world setting which may contribute to quality management programs and towards value-based healthcare.

Catheter ablation of paroxysmal atrial fibrillation using high-density mapping-guided substrate modification

BACKGROUND

This study aimed to evaluate the effect of substrate modification in paroxysmal atrial fibrillation (AF) patients prior to circumferential pulmonary vein isolation (CPVI).

METHODS

Patients without left atrial low-voltage and/or scar areas were defined as Group A. Patients with left atrial low-voltage and/or scar areas underwent regular CPVI (Group B) or substrate modification after CPVI (Group C). The procedural success rate and differences in the left atrial diameter (LAD) among groups were compared at 1 year postoperatively.

RESULTS

The procedural success rate in Group C was comparable to that in Group A (P > 0.05) and was significantly higher than that in Group B (P < 0.01). The LAD of patients in Groups A and C significantly decreased at 1 year postoperatively compared to that prior to the surgery (P < 0.05). However, no significant difference was noted in Group B.

CONCLUSIONS

Our study demonstrated that substrate modification could contribute to the single catheter ablation surgery success rate in patients with paroxysmal AF and narrow LAD.

Tobacco smoking and the risk of atrial fibrillation: A systematic review and meta-analysis of prospective studies

Background

Epidemiological studies on smoking and atrial fibrillation have been inconsistent, with some studies showing a positive association while others have found no association. It is also unclear whether there is a dose–response relationship between the number of cigarettes smoked or pack-years and the risk of atrial fibrillation. We conducted a systematic review and meta-analysis to clarify the association.

Design

Systematic review and meta-analysis.

Methods

We searched the PubMed and Embase databases for studies of smoking and atrial fibrillation up to 20 July 2017. Prospective studies and nested case–control studies within cohort studies reporting adjusted relative risk estimates and 95% confidence intervals (CIs) of atrial fibrillation associated with smoking were included. Summary relative risks (95% CIs) were estimated using a random effects model.

Results

Twenty nine prospective studies (22 publications) were included. The summary relative risk was 1.32 (95% CI 1.12–1.56, I2 = 84%, n = 11 studies) for current smokers, 1.09 (95% CI 1.00–1.18, I2 = 33%, n = 9) for former smokers and 1.21 (95% CI 1.12–1.31, I2 = 80%, n = 14) for ever smokers compared to never smokers. Comparing current versus non-current smokers the summary relative risk was 1.33 (95% CI 1.14–1.56, I2 = 78%, n = 10). The summary relative risk was 1.14 (95% CI 1.10–1.20, I2 = 0%, n = 3) per 10 cigarettes per day and 1.16 (95% CI 1.09–1.25, I2 = 49%, n = 2) per 10 pack-years and there was no evidence of a non-linear association for cigarettes per day, Pnon-linearity = 0.17.

Conclusions

The current meta-analysis suggests that smoking is associated with an increased risk of atrial fibrillation in a dose-dependent matter, but the association is weaker among former smokers compared to current smokers.

The impact of atrial fibrillation in patients with COPD during hospitalization

Background

Atrial fibrillation (AF) occurs frequently in patients with COPD. There are limited data about the impact of AF in hospitalized COPD patients on other serious health outcomes, such as acute organ dysfunction, severe sepsis, and respiratory failure. The aim of our study was to delineate the impact of AF in hospitalized COPD patients.

Methods

We defined COPD populations with and without AF from the National Health Insurance database in Taiwan. The control subjects (patients with COPD without AF) were selected from the population of COPD patients who had no history of AF and were matched to the COPD patients with AF by age (±1 year), gender, and the year of COPD diagnosis (±1 year). The primary outcome was the time to any first event, which included acute organ dysfunction, severe sepsis, respiratory failure, and death during the hospitalization period. Secondary outcomes, which also included acute organ dysfunction, severe sepsis, respiratory failure, and death, were estimated separately over time.

Results

The primary outcome probability was higher in COPD patients with AF than in COPD patients without AF, with an adjusted HR (aHR) of 1.169 (95% confidence interval [CI]: 1.034–1.320), and higher risks of acute organ dysfunction and respiratory failure were also observed in the former group, with aHRs of 1.179 (95% CI: 1.0370–1.339) and 1.176 (95% CI: 1.006–1.374), respectively.

Conclusion

Compared with COPD patients without AF, those with AF had a higher risk of hepatic dysfunction and respiratory failure.

Incidence and risk factors of atrial fibrillation in Asian COPD patients

Objective

To investigate the incidence and risk factors of atrial fibrillation (AF) in Asian chronic obstructive pulmonary disease (COPD) patients.

Patients and methods

We selected a study population older than 40 years with a COPD diagnosis and who had used at least one inhaled bronchodilator medication between 1998 and 2012. The date of the index COPD diagnosis was defined as the index date. We excluded patients with a history of AF, significant mitral valve disease, disorders of the thyroid gland, or ischemic heart disease before the index date. We followed all patients from the index date to the day of AF occurrence, the day of death, or the date of December 31, 2013. The baseline of comorbidities was identified before the index date. Comorbidities included hypertension, diabetes mellitus, end-stage renal disease, congenital heart failure, stroke, peripheral arterial occlusive disease, and malignancy.

Results

We included 6,208 COPD patients and 12,409 patients without COPD. The incidence of AF was higher in COPD patients than in those without COPD. The adjusted hazard ratio (HR) for AF among those with COPD was 2.23 with a 95% confidence interval (CI) of 1.98–2.51 compared to those without COPD. After multiple analyses, patients with hypertension (HR 1.43 [95% CI =1.26–1.62]) or heart failure (HR 2.36 [95% CI =1.81–3.08]) were found to have a significantly higher incidence of AF than those without these conditions.

Conclusion

It is important for physicians to monitor, prevent, and provide early intervention for AF in COPD patients with hypertension or heart failure.