Global Burden of Atrial Fibrillation and Flutter by National Income: Results From the Global Burden of Disease 2019 Database.

Background Atrial fibrillation (AF) and atrial flutter (AFL) are common conditions that can lead to significant morbidity and death. We aimed to understand the distribution and disparities of the global burden of AF/AFL as well as the underlying risk factors. Methods and Results Data on the AF/AFL burden from the Global Burden of Disease data set were analyzed for the years 1990 to 2019, with countries grouped into low, lower-middle, upper-middle, and high national income classes according to World Bank categories. Data were supplemented with World Health Organization and World Bank information. The prevalence of AF/AFL has more than doubled (+120.7%) since 1990 in all income groups, though with a larger increment in middle-income countries (+146.6% in lower-middle- and +145.2% in upper-middle-income countries). In absolute numbers, 63.4% of AF/AFL cases originate from upper-middle-income countries, although the relative prevalence is highest in high-income countries. Prevalence of AF/AFL appears to be correlated with medical doctor rate and life expectancy. The most relevant AF/AFL risk factors are unevenly distributed among income classes, with elevated blood pressure as the only risk factor that becomes less common with increasing income. The development of these risk factors differed over time. Conclusions The global burden of AF/AFL is increasing in all income groups and is more pronounced in middle-income countries, with further growth to be expected. Underdiagnosis of AF/AFL in low- and middle-income countries may contribute to lower reported prevalence. The risk factor distribution varies between income groups.

Harmful Impact of Tobacco Smoking and Alcohol Consumption on the Atrial Myocardium.

Tobacco smoking and alcohol consumption are widespread exposures that are legal and socially accepted in many societies. Both have been widely recognized as important risk factors for diseases in all vital organ systems including cardiovascular diseases, and with clinical manifestations that are associated with atrial dysfunction, so-called atrial cardiomyopathy, especially atrial fibrillation and stroke. The pathogenesis of atrial cardiomyopathy, atrial fibrillation, and stroke in context with smoking and alcohol consumption is complex and multifactorial, involving pathophysiological mechanisms, environmental, and societal aspects. This narrative review summarizes the current literature regarding alterations in the atrial myocardium that is associated with smoking and alcohol.

The Relationship Between Vitamin D and Postoperative Atrial Fibrillation: A Prospective Cohort Study.

Background and Aims: The relationship between postoperative atrial fibrillation (POAF) and 25-hydroxyvitamin D [25(OH)D] concentration as well as vitamin D supplementation has been discussed controversially. The relation of pre-operative vitamin D status and POAF remains unclear. Methods and Results: We analysed the risk of POAF in a prospective, observational cohort study of n = 201 patients undergoing coronary artery bypass graft surgery (CABG) with 25(OH)D concentration. The median age was 66.6 years, 15.4% were women. The median (25th/75th percentile) vitamin D concentration at baseline was 17.7 (12.6/23.7) ng/ml. During follow-up we observed 48 cases of POAF. In age, sex, and creatinine-adjusted analyses, 25(OH)D was associated with an increased risk of POAF, though with borderline statistical significance [odds ratio (OR) 1.85, 95% confidence interval (CI) 0.87-3.92, p-value 0.107], in further risk factor-adjusted analyses the results remained stable (OR 1.99, 95% CI 0.90-4.39, p-value 0.087). The subgroup with vitamin D supplementation at baseline showed an increased risk of POAF (OR 5.03, 95% CI 1.13-22.33, p-value 0.034). Conclusion: In our contemporary mid-European cohort, higher 25(OH)D concentration did not show a benefit for POAF in CABG patients and may even be harmful, though with borderline statistical significance. Our data are in line with a recent randomised study in community-based adults and call for further research to determine both, the clinical impact of elevated 25(OH)D concentration and vitamin D supplementation as well as the possible underlying pathophysiological mechanisms.

Risk prediction of atrial fibrillation in the community combining biomarkers and genetics.

AIMS: Classical cardiovascular risk factors (CVRFs), biomarkers, and common genetic variation have been suggested for risk assessment of atrial fibrillation (AF). To evaluate their clinical potential, we analysed their individual and combined ability of AF prediction. METHODS AND RESULTS: In N = 6945 individuals of the FINRISK 1997 cohort, we assessed the predictive value of CVRF, N-terminal pro B-type natriuretic peptide (NT-proBNP), and 145 recently identified single-nucleotide polymorphisms (SNPs) combined in a developed polygenic risk score (PRS) for incident AF. Over a median follow-up of 17.8 years, n = 551 participants (7.9%) developed AF. In multivariable-adjusted Cox proportional hazard models, NT-proBNP [hazard ratio (HR) of log transformed values 4.77; 95% confidence interval (CI) 3.66-6.22; P < 0.001] and the PRS (HR 2.18; 95% CI 1.88-2.53; P < 0.001) were significantly related to incident AF. The discriminatory ability improved asymptotically with increasing numbers of SNPs. Compared with a clinical model, AF risk prediction was significantly improved by addition of NT-proBNP and the PRS. The C-statistic for the combination of CVRF, NT-proBNP, and the PRS reached 0.83 compared with 0.79 for CVRF only (P < 0.001). A replication in the Dutch Prevention of REnal and Vascular ENd-stage Disease (PREVEND) cohort revealed similar results. Comparing the highest vs. lowest quartile, NT-proBNP and the PRS both showed a more than three-fold increased AF risk. Age remained the strongest risk factor with a 16.7-fold increased risk of AF in the highest quartile. CONCLUSION: The PRS and the established biomarker NT-proBNP showed comparable predictive ability. Both provided incremental predictive value over standard clinical variables. Further improvements for the PRS are likely with the discovery of additional SNPs.