Smoking and risk of atrial fibrillation

Borderline personality disorder and risk of atrial fibrillation: insights from a bidirectional Mendelian randomization study

Background

Atrial fibrillation (AF) is one of the most common form of arrhythmia. Previous studies have shown a link between AF and mental illness. However, the causal relationship between mental illness and AF remains unclear. The purpose of this study was to investigate the bidirectional causal relationship between borderline personality disorder (BPD) and AF.

Method

We used the bidirectional Two-sample Mendelian randomization (TSMR) method to evaluate the causal relationship between BPD and AF. Instrumental variables associated with BPD were derived from a genome-wide association study involving 214,816 Europeans (2,637 cases and 212,179 controls). We then obtained atrial fibrillation data from the GWAS meta-analysis (60,620 cases and 970,216 controls). The TSMR analyses were performed in five methods, namely fixed-effect inverse-variance weighted (IVW) method、random-effect IVW method, MR Egger regression method, Weighted median method and Simple mode method. Several sensitivity analyses are used to test the robustness of positive results.

Results

The fixed-effect inverse-variance weighted model [Odds ratio (OR), 1.033, 95% confidence interval (CI), 1.011-1.056, P = 0.0031], random-effect inverse-variance weighted model (OR, 1.033; 95%CI, 1.005-1.062; P = 0.0191) and Weighted median (OR, 1.034; 95%CI, 1.002-1.068; P = 0.0394) all showed that genetically predicted BPD was associated with an increased risk of AF. Sensitivity analysis using other MR Methods, including the MR-Egger intercept, MR-Presso method, and leave-one-out analyses, showed that the results were robust. In reverse MR analysis, there was no causal relationship of AF on BPD.

Conclusion

Our study provides a causal relationship between BPD and AF. This means that patients with BPD should be monitored for the occurrence of AF. Early screening and proper management of BPD may show anti-arrhythmic benefits.

Global burden of atrial fibrillation/atrial flutter and its attributable risk factors from 1990 to 2021

AIMS

To devise effective preventive measures, a profound understanding of the evolving patterns and trends in atrial fibrillation (AF) and atrial flutter (AFL) burdens is pivotal. Our study was designed to quantify the burden and delineate the risk factors associated with AF and AFL across 204 countries and territories spanning 1990-2021.

METHODS AND RESULTS

Data pertaining to AF and AFL were sourced from the Global Burden of Disease Study 2021. The burden of AF/AFL was evaluated using metrics such as incidence, disability-adjusted life years (DALYs), deaths, and their corresponding age-standardized rates (ASRs), stratified by age, sex, socio-demographic index (SDI), and human development index (HDI). The estimated annual percentage change was employed to quantify changes in ASRs. Population attributable fractions were calculated to determine the proportional contributions of major risk factors to age-standardized AF/AFL deaths. This analysis encompassed the period from 1990 to 2021. Globally, in 2021, there were 4.48 million incident cases [95% uncertainty interval (UI): 3.61-5.70], 8.36 million DALYs (95% UI: 6.97-10.13) and 0.34 million deaths (95% UI: 0.29-0.37) attributed to AF/AFL. The AF/AFL burden in 2021, as well as its trends from 1990 to 2021, displayed substantial variations based on gender, SDI quintiles, and geographical regions. High systolic blood pressure emerged as the leading contributor to age-standardized AF/AFL incidence, prevalence, death, and DALY rate globally among all potential risk factors, followed closely by high body mass index.

CONCLUSION

Our study underscores the enduring significance of AF/AFL as a prominent public health concern worldwide, marked by profound regional and national variations. Despite the substantial potential for prevention and management of AF/AFL, there is a pressing imperative to adopt more cost-effective strategies and interventions to target modifiable risk factors, particularly in areas where the burden of AF/AFL is high or escalating.

Global, regional, and national burden of disease study of atrial fibrillation/flutter, 1990-2019: results from a global burden of disease study, 2019

Background

Data from the Global Burden of Disease, Injury, and Risk Factor Study 2019 (GBD 2019) was used to assess the burden and change in prevalence, incidence, deaths, disability-adjusted life years, and risk factors for atrial fibrillation/flutter in 204 countries and territories between 1990 and 2019.

Methods

Incidence, prevalence, deaths, disability-adjusted life years (DALYs), and their age-standardized rates of AF/AFL were analyzed by age, sex, socio-demographic index (SDI), and human development index (HDI) using the Global Burden of Disease study 2019 (GBD2019) results，and risk factors for AF/AFL (mainly high systolic blood pressure, high body-mass index, alcohol use, smoking and diet high in sodium) were differentially analyzed.

Results

There are 59.70 million (95% uncertainty interval (UI) 45.73–75.29 million) AF/AFL patients worldwide in 2019, with 4.72 million (95% uncertainty interval (UI) 3.64–5.96 million) new cases and 0.315 million deaths (95% uncertainty interval (UI) 0.268–0.361 million) and 8.39 million disability-adjusted years (95% uncertainty interval (UI) 6.69–10.54 million). The highest risk factor for deaths, DALYs attributable to AF/AFL in 2019 was high systolic blood pressure, high body-mass index, alcohol use, smoking, and diet high in sodium. It is estimated that between 2030 and 2034, the total incidence of male AF/ AFL will be 16.08 million, and the total number of deaths will be 1.01 million. For females, the total number of incidence is 16.85 million, and the total number of deaths is 1.49 million.

Conclusions

AF/AFL remains a major global public health problem, although the ASR of prevalence, incidence, and DALY at the worldwide level showed a decreasing trend from 1990 to 2019(the ASR of deaths increased slightly). However, the unfavorable trend observed in this study in countries with lower SDI suggests that current prevention and treatment strategies should be reoriented. Some countries should develop more targeted and specific strategies to prevent the increase of AF/AFL.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14403-2.

Association between noise exposure and atrial fibrillation: a meta-analysis of cohort studies

Noise has become an important environmental risk factor. Some studies have shown that exposure to noise can cause coronary artery disease, high blood pressure, and stroke. At present, the relationship between noise exposure and the risk of atrial fibrillation (AF) is inconsistent. Based on previous studies, we proposed the hypothesis that noise exposure is associated with a higher risk of AF. Eight databases, such as PubMed, Embase, Cochrane Library, and Web of Science, were searched from inception until January 5, 2022. The pooled relative risk (RR) with its 95% confidence interval (CI) was used to estimate the association between AF and highest noise level and per 10 dB (A) increment of noise. According to the size of heterogeneity, the random or fixed effects model was adopted as the pooling method. A total of 5 articles comprising 3,866,986 participants were identified, providing 7 estimates of highest noise level and 6 estimates of per 10 dB (A) increment of noise exposure. For the highest noise level, there was a statistically significant association between noise exposure and the risk of AF (RR = 1.05; 95% CI: 1.02-1.09; I² = 44.1%). In addition, we found the risk of AF for per 10 dB (A) increment of noise exposure was 1.01 (95% CI: 1.00-1.02; I² = 81.3%). In summary, our study found that noise exposure was associated with a higher risk of AF. More high-quality studies are needed in the future to confirm these conclusions given the limitations of study.

Updates on epicardial adipose tissue mechanisms on atrial fibrillation

Obesity is a well-known risk factor for atrial fibrillation (AF). Local epi-myocardial or intra-myocardial adiposity caused by aging, obesity, or cardiovascular disease (CVD) is considered to be a better predictor of the risk of AF than general adiposity. Some of the described mechanisms suggest that epicardial adipose tissue (EAT) participates in structural remodeling owing to its endocrine activity or its infiltration between cardiomyocytes. Epicardial fat also wraps up the ganglionated plexi that reach the myocardium. Although the increment of volume/thickness and activity of EAT might modify autonomic activity, autonomic system dysfunction might also change the endocrine activity of epicardial fat in a feedback response. As a result, new preventive therapeutic strategies are focused on reducing adiposity and weight loss before AF ablation or inhibiting autonomic neurotransmitter secretion on fat pads during open-heart surgery to reduce the recurrence or postoperative risk of AF. In this manuscript, we review some of the novel findings regarding the pathophysiology and associated risk factors of AF, with special emphasis on the role of EAT in the electrical, structural, and molecular mechanisms of AF initiation and maintenance. In addition, we have included a brief note provided on epicardial fat preclinical models that could be useful for identifying new therapeutic targets.

Beyond Ablation in Atrial Fibrillation: 10 Steps to Better Control

The prevention and treatment of atrial fibrillation includes risk factor modification beyond ablation, with lifestyle modifications including treatment of obesity through diet and moderate exercise being at the top of the list. Losing 10% of body weight if obese, a plant-based diet, exercise, maintaining systolic blood pressure below 130 mm Hg, treatment of sleep disorders and obstructive sleep apnea, stress management, and treatment of depression and anxiety should all be included in treatment. Maximizing evidence-based treatment of chronic obstructive pulmonary disease and diabetes is also paramount.

Clinical Risk Factors Associated with Ambulatory Outcome in Acute Ischemic Stroke Patients Smokers Treated with Thrombolytic Therapy

BACKGROUND

Patients who have suffered an acute ischemic stroke (AIS) and are smokers may have a better outcome following thrombolytic therapy when compared with non-smokers. While this finding is controversial, data on baseline clinical risk factors to predict treatment efficacy of thrombolytic therapy using ambulatory status in patients who suffered AIS and are smokers is not common.

METHODS

Between 2010 and 2016, retrospective data on patients who have suffered an AIS and received recombinant tissue plasminogen activator (rtPA) were obtained from Greenville health system registry. Assessment of clinical risk factors and the likelihood of an improvement in post-stroke ambulation among smokers and non-smokers was carried out using multivariate logistic regression.

RESULTS

Of 1001 patients, 70.8% were smokers and 29.2% non-smokers. Among the smokers and non-smokers, 74.6% and 84.6% improvement in ambulation respectively at discharge. The odds of improved ambulation decrease among smokers as age group increases compared to those below 50 [(60-69 years, aOR, 0.30, 95% C.I, 0.108-0.850, p < 0.05), (70-79 years aOR, 0.27, 95% C.I, 0.096-0.734, p < 0.05), (80+ years aOR, 0.16, 95% C.I, 0.057-0.430, P < 0.01). Patients with National Institute of Health Stroke Scale Score (NIHSS) score > 7 (reference <7) were 91% less likely to have improved ambulation among smokers and non-smokers (aOR, 0.09, 95% C.I, 0.055-0.155, P = 0.01), and (aOR, 0.08, 95% C.I, 0.027-0.214, P = 0.01) respectively. Atrial fibrillation was an independent predictor of decreased improvement in ambulation only among smokers (aOR, 0.58, 95% C.I, 0.356-0.928 P < 0.05).

CONCLUSION

Our findings suggest that elderly smokers with atrial fibrillation would benefit more from aggressive management of atrial fibrillation than non-smokers.

Does Chronic Intestinal Inflammation Promote Atrial Fibrillation: A Mendelian Randomization Study With Populations of European Ancestry

Background: Inflammatory bowel disease (IBD), comprising ulcerative colitis (UC), and Crohn's disease (CD), has been reported to be associated with an increased risk of atrial fibrillation (AF). However, the causal role of the chronic intestinal inflammation (CII) in the development of AF remains controversial. We use Mendelian randomization (MR) analysis to explore the causal inference of CII on AF. Methods: A two-sample MR analysis was performed to estimate the potential causal effect of CII on AF. Statistical summaries for the associations between single nucleotide polymorphisms (SNPs) and phenotypes of CII were obtained from genome-wide association studies (GWAS) with cohorts of CD (n = 51,874), UC (n = 47,745), and IBD (n = 65,642) of European descent. The GWAS of 1,030,836 people of European ancestry, including 60,620 AF cases and 970,216 controls was collected to identify genetic variants underlying AF. The causal inference was estimated using the multiplicative random effects inverse-variance weighted method (IVW). The methods of MR-Egger, simple median, and weighted median were also employed to avoid the bias of pleiotropy effects. Results: Using three sets of SNPs (75 SNPs of CD, 60 SNPs of UC, and 95 SNPs of IBD), multiplicative random-effect IVW model estimated a universal null effect of CII on AF (CD: OR = 1.0059, 95% CI: 0.9900, 1.0220, p = 0.47; UC: OR = 1.0087, 95% CI: 0.9896, 1.0281, p = 0.38; IBD: OR = 1.0080, 95% CI: 0.9908, 1.0255, p = 0.37). Similar results were observed using the MR-Egger, simple median, weighted median methods. Conclusion: As opposing to the traditional observational studies, our two-sample MR analysis did not find enough evidence to support a causal role of either CD or UC in the development of AF.

Smoking Accelerates Atrioventricular Conduction in Humans Concordant with Increased Dopamine Release

Smoking is associated with cardiac arrhythmia, stroke, heart failure, and sudden cardiac arrest, all of which may derive from increased sympathetic influence on cardiac conduction system and altered ventricular repolarization. However, knowledge of the effects of smoking on supraventricular conduction, and the role of the sympathetic nervous system in them, remains incomplete. Participants with intermediate-high cardiovascular disease risk were measured for urinary catecholamines and cotinine, and 12-lead electrocardiograms (ECGs) were measured for atrial and atrioventricular conduction times, including P duration, PR interval, and PR segment (lead II), which were analyzed for associations with cotinine by generalized linear models. Statistical mediation analyses were then used to test whether any significant associations between cotinine and atrioventricular conduction were mediated by catecholamines. ECG endpoints and urinary metabolites were included from a total of 136 participants in sinus rhythm. Atrial and atrioventricular conduction did not significantly differ between smokers (n = 53) and non-smokers (n = 83). Unadjusted and model-adjusted linear regressions revealed cotinine significantly and inversely associated with PR interval and PR segment, but not P duration. Dopamine, norepinephrine, and epinephrine all inversely associated with PR interval, whereas only dopamine was also inversely associated with PR segment (p < 0.05). Dopamine and norepinephrine (but not epinephrine) also associated positively with cotinine. Dopamine mediated the relationship between cotinine and PR interval, as well as the relationship between cotinine and PR segment. Smoking is associated with accelerated atrioventricular conduction and elevated urinary dopamine and norepinephrine. Smoking may accelerate atrioventricular nodal conduction via increased dopamine production.

Association between clustering of unhealthy lifestyle factors and risk of new-onset atrial fibrillation: a nationwide population-based study

We aimed to investigate the association between the combination of unhealthy lifestyle and risk of AF. Subjects aged 66 years who underwent health examination from 2009 to 2015 were included. The cohort was divided into 8 groups by the combination of unhealthy lifestyle including current smoking, heavy drinking (> 30 g/day), and lack of regular exercise, and followed up for new-onset AF till December 31, 2017. Among 1,719,401 subjects, 47,334 had incident AF (5.5 per 1000 person-years) during a 5-year mean follow-up period. Lack of regular exercise was the most powerful factor to be associated with a higher risk of AF as a single factor (adjusted hazard ratio 1.11, 95% confidence interval 1.08–1.13). Amongst combinations of two unhealthy lifestyle factors, current smoking with heavy drinking, lack of regular exercise with heavy drinking, and lack of regular exercise with current smoking were associated with a 6%, 15%, and 20% higher risks of AF, respectively. A cluster of three unhealthy lifestyle components was associated with a 22% higher risk of AF. Increased numbers of unhealthy lifestyle factors were associated with a higher risk of incident AF. These findings support the promotion of a healthy lifestyle to lower the risk of new-onset AF.

Prevalence and associated factors of undiagnosed atrial fibrillation among end-stage renal disease patients on maintenance haemodialysis: a cross-sectional study

BACKGROUND

Atrial fibrillation (AF) is the most prevalent sustained arrhythmia worldwide and it aggravates cardiovascular morbidity and mortality; however, this is largely under-diagnosed. Moreover, among end-stage renal disease patients on haemodialysis, AF is substantially more common and serious. The researchers conducted this study to assess the prevalence of, and the factors correlated with AF in Jordanian haemodialysis patients.

METHODS

In a cross-sectional analysis conducted from October 2018 to February 2019 in four tertiary hospitals, the researchers enrolled all consenting patients aged 18 years or older who were on haemodialysis for at least three months prior to the study. We screened for AF clinically by pulse palpation, precordial auscultation, by an automated blood pressure monitor and an electrocardiogram. The researchers reported qualitative variables as counts and frequencies, while continuous variables were summarised using the mean or median where necessary. We used multiple logistic regression with backward selection to identify independent risk factors of AF.

RESULTS

A total of 231 patients were enrolled; mean age was 54.8 ± 15.6 years (from 20 to 86), and 44.3% of them were women. The prevalence of AF was found to be 7.8% (95% CI, 4.8-12.2), with no gender disparity. Age (adjusted odds ratio [AOR] = 1.05; 95% CI, 1.01-1.10; p = 0.031), history of ischaemic heart disease (AOR = 3.74; 95% CI, 1.09-12.34; p = 0.033), history of smoking (AOR = 0.15; 95% CI, 0.02-0.60; p = 0.019), and low interdialytic weight gain (AOR = 0.50: 95% CI, 0.25-0.91; p = 0.031) were independently correlated to AF.

CONCLUSIONS

The prevalence of AF among patients on maintenance haemodialysis is high, but largely undiagnosed. AF is generally associated with advancing age, history of ischaemic heart disease, lower interdialytic weight gain, and history of smoking. We suggest routine check-up of AF in this high-risk group of patients as anticoagulant therapy if indicated may prevent serious complications. However, there is a need for large-scale cohort studies and for the creation of regional chronic kidney disease and dialysis registries in the Middle East region.

Atrial fibrillation: A review of modifiable risk factors and preventive strategies

Atrial fibrillation (AF), as the most common cardiac arrhythmia worldwide, is associated with increased mortality and morbidity. Successful therapeutic strategies have been introduced so far, but they are associated with significant costs. Therefore, identification of modifiable risk factors of AF and the development of appropriate preventive strategies may play a substantial role in promoting community health and reducing health care system costs. Modifiable cardiovascular risk factors including obesity, hypertension, diabetes mellitus, obstructive sleep apnea, alcohol consumption, smoking, and sedentary lifestyles have been proposed as possible contributors to the development and progression of AF. In this review, we discuss the role of modifiable risk factors in the development and management of AF and the evidence for the underlying mechanism for each of the potential risk factor.