Dose-response analysis between hemoglobin A1c and risk of atrial fibrillation in patients with and without known diabetes

Association between baseline glycated hemoglobin level and atrial fibrillation recurrence following cryoballoon ablation among patients with and without diabetes

OBJECTIVES

The study aims to assess the effect of baseline glycated hemoglobin (HbA1c) levels on atrial fibrillation (AF) recurrence following cryoballoon ablation in patients with and without diabetes.

METHODS

Consecutive AF patients receiving first cryoballoon ablation between April 2018 and April 2021 were included. AF recurrence and other clinical outcomes were recorded for a minimum of 12 months post-ablation, with regular assessments at 3, 6, and 12 months, followed by annual check-ups. The primary outcome was AF recurrence after ablation at longest follow-up. Multivariate Cox proportional hazards regression models were utilized to calculate the hazard ratio (HR) and 95% CI per standard deviation (SD) increase of baseline HbA1c level.

RESULTS

335 patients were included in the analysis. The mean age was 61.7 years, 61.8% were male. 12.8% had type 2 diabetes, and 81.7% of patients had paroxysmal AF. The median level of HbA1c was 5.3%, and the mean CHA2DS2-VASc score was 1.8. All cryoballoon ablation procedures, utilizing a 28-mm balloon, achieved successful pulmonary vein isolation. Over a median follow-up of 18 months, 105 patients (31.3%) experienced AF recurrence. In multivariate Cox proportional hazards analysis, a higher HbA1c level, persistent AF (HR 1.91, 95% CI 1.08 to 3.39, P = 0.026), alcohol consumption (HR 2.67, 95% CI 1.33 to 5.37, P = 0.006), and Nadir RSPV (HR 1.04, 95% CI 1.00 to 1.08, P = 0.005) were significant predictors of AF recurrence. Per-SD increase of HbA1c was associated with a 1.75-fold increase risk of AF recurrence (HR 1.75, 95% CI 1.39 to 2.21, P < 0.001). Subgroup analysis revealed that a higher HbA1c level was associated with a higher risk of AF recurrence in patients with and without diabetes, and in patients with paroxysmal and persistent AF.

CONCLUSION

Baseline HbA1c level was an independent predictor of AF recurrence following cryoablation, both in patients with and without diabetes.

Associations of combined polygenic risk score and glycemic status with atrial fibrillation, coronary artery disease and ischemic stroke

BACKGROUND

It is unknown whether high hemoglobin A1c (HbA1c) is associated with increases in the risk of cardiovascular disease among individuals with elevated genetic susceptibility. We aimed to investigate the association between HbA1c and atrial fibrillation (AF), coronary artery disease (CAD), and ischemic stroke according to the polygenic risk score (PRS).

METHODS

The UK Biobank cohort included 502,442 participants aged 40-70 years who were recruited from 22 assessment centers across the United Kingdom from 2006 to 2010. This study included 305,605 unrelated individuals with available PRS and assessed new-onset AF, CAD, and ischemic stroke. The participants were divided into tertiles based on the validated PRS for each outcome. Within each PRS tertiles, the risks of incident events associated with HbA1c levels were investigated and compared with HbA1c < 5.7% and low PRS. Data were analyzed from November 2022 to May 2023.

RESULTS

Of 305,605 individuals, 161,605 (52.9%) were female, and the mean (SD) age was 56.6 (8.1) years. During a median follow-up of 11.9 (interquartile range 11.1-12.6) years, the incidences of AF, CAD, and ischemic stroke were 4.6, 2.9 and 1.1 per 100 person-years, respectively. Compared to individuals with HbA1c < 5.7% and low PRS, individuals with HbA1c ≥ 6.5% and high PRS had a 2.67-times higher risk for AF (hazard ratio [HR], 2.67; 95% confidence interval (CI), 2.43-2.94), 5.71-times higher risk for CAD (HR, 5.71; 95% CI, 5.14-6.33) and 2.94-times higher risk for ischemic stroke (HR, 2.94; 95% CI, 2.47-3.50). In the restricted cubic spline models, while a U-shaped trend was observed between HbA1c and the risk of AF, dose-dependent increases were observed between HbA1c and the risk of CAD and ischemic stroke regardless PRS tertile.

CONCLUSIONS

Our results suggest that the nature of the dose-dependent relationship between HbA1c levels and cardiovascular disease in individuals with different PRS is outcome-specific. This adds to the evidence that PRS may play a role together with glycemic status in the development of cardiovascular disease.

Evaluation of the effect of preoperative HbA1c value on development of postoperative atrial fibrillation in diabetic patients with on-pump coronary artery bypass graft

BACKGROUND

We aimed to determine the relationship between hemoglobin A1c (HbA1c) levels and the development of postoperative atrial fibrillation (PoAF).

METHODS

Two hundred and eighty-eight patients diagnosed with diabetes mellitus and undergoing on-pump coronary bypass were included in the study. Those with serum HbA1c levels between 5.5% and 7.0% were defined as Group 1, those with serum HbA1c levels between 7.1% and 8.9% were defined as Group 2, while those with serum HbA1c levels 9.0% and above formed Group 3. Data between groups were compared. The predictive values of the independent variables for the development of PoAF were measured.

RESULTS

We did not find a difference between groups in terms of development PoAF (p = .170). The presence of hypertension was determined as an independent predictor for the development of PoAF (p = .003), but not HbA1c levels (p = .134). There was 50.5% sensitivity and 61.1% specificity for HbA1c values of 9.06% and above to predict PoAF (area under curve: 0.571, p = .049).

CONCLUSIONS

HbA1c levels were not an independent predictor of PoAF development. However, we think that high HbA1c levels may be a risk factor for the development of PoAF.

The complex interplay between diabetes mellitus and atrial fibrillation

INTRODUCTION

: A growing body of evidence suggests that diabetes mellitus (DM) is associated with an increased risk of new-onset atrial fibrillation (AF) and contributes to suboptimal arrhythmia control and poor prognosis in patients with AF. The high prevalence of AF among patients with DM is primarily attributed to common risk factors, shared pathophysiological mechanisms, and associated atrial remodeling and autonomic dysfunction.

AREAS COVERED

: This comprehensive review covers the current data on the role of DM in the development and prognosis of AF. In addition, we review the impact of anti-DM medications on AF prevention and the role of anticoagulation in patients with coexisting DM and AF.

EXPERT OPINION

: DM is independently associated with new-onset AF, and the coexistence of these two conditions contributes to poor outcomes, from reduced quality of life to increased risks of thromboembolic events, heart failure, and mortality. Despite this strong link, the current evidence is insufficient to recommend routine screening for AF in patients with DM. Although some observations exist on preventing AF with anti-DM medications, randomized controlled trials are warranted to explore the proposed benefits of novel anti-DM medicines in reducing the risk of incident AF.

Glycemic control and atrial fibrillation: an intricate relationship, yet under investigation

Atrial fibrillation (AF) and diabetes mellitus (DM) constitute two major closely inter-related chronic cardiovascular disorders whose concurrent prevalence rates are steadily increasing. Although, the pathogenic mechanisms behind the AF and DM comorbidity are still vague, it is now clear that DM precipitates AF occurrence. DM also affects the clinical course of established AF; it is associated with significant increase in the incidence of stroke, AF recurrence, and cardiovascular mortality. The impact of DM on AF management and prognosis has been adequately investigated. However, evidence on the relative impact of glycemic control using glycated hemoglobin levels is scarce. This review assesses up-to-date literature on the association between DM and AF. It also highlights the usefulness of glycated hemoglobin measurement for the prediction of AF and AF-related adverse events. Additionally, this review evaluates current anti-hyperglycemic treatment in the context of AF, and discusses AF-related decision-making in comorbid DM. Finally, it quotes significant remaining questions and sets some future strategies with the potential to effectively deal with this prevalent comorbidity.

Increased hemoglobin A1c level associates with low left atrial appendage flow velocity in patients of atrial fibrillation

BACKGROUND AND AIMS

High hemoglobin A1c (HbAlc) level is associated with increased cardiovascular disease risk and thromboembolic events [1]. The study sought to explored the association between HbAlc and left atrial appendage flow velocity (LAAV) among non-valvular atrial fibrillation (AF) patients.

METHODS AND RESULTS

A total of 249 consecutive non-valvular AF patients who underwent transesophageal echocardiography (TEE) were divided into two subgroups according to the median of LAAV level (<45 cm/s, ≥45 cm/s). Blood samples and other baseline clinical data of all patients were collected and analyzed. The low LAAV group included 126 patients and the high LAAV group included 123 patients. Patients in the low LAAV group were older and had a higher percentage of persistent AF, chronic heart failure, and higher CHA2DS2-VASc score (P < 0.05). HbAlc level in the low LAAV group was significantly higher than the high LAAV group [6.1 (5.7-6.5)% vs 5.9 (5.6-6.2)%, P = 0.010]. The low LAAV group had larger left atrial diameter (LAD), left atrial area (LAA), higher left atrial pressure (LAP), and lower left ventricular ejection fraction (LVEF) (P < 0.05). Spearman rank correlation analysis showed that the HbAlc level was negatively correlated with LAAV (r = -0.211, P = 0.001). Multivariate analysis indicated that female gender (OR = 2.233, 95% CI 1.110-4.492, P = 0.024), persistent AF (OR = 6.610, 95% CI 3.109-14.052, P < 0.001), and HbAlc (OR = 1.903, 95% CI 1.092-3.317, P = 0.023) were independent factors that associated with low LAAV in AF patients.

CONCLUSION

Increased HbAlc level is associated with decreased LAAV and may reflect a low contractile function of the left atrial appendage.

Biochemical predictors of postoperative atrial fibrillation following cardiac surgery

Background

New-onset postoperative atrial fibrillation (POAF) is common after cardiac surgery. Early identification of its risk factors during the preoperative period would help in reducing the associated morbidity, mortality, and healthcare costs.

Aim of the study

This study aimed to identify the predictors of POAF following open cardiac surgery, with emphasis on biochemical parameters.

Methods

A total of 1191 patients with no preoperative atrial fibrillation (AF) and undergoing open cardiac surgery for any reason were included in this retrospective study. Data on clinical and biochemical parameters, the occurrence of new-onset AF, and its clinical course were retrieved from the hospital database.

Results

During the early postoperative period 330 patients (27.7%) developed atrial fibrillation, at median third postoperative day (range 1–6 days) and 217 (65.8%) responded to treatment. Multivariate analysis identified the following as the significant independent predictors of any POAF: EF < 60% (Odds ratio (OR), 2.6), valvular intervention (OR, 2.4), liver failure (OR, 2.4), diabetes (OR, 1.6), low hematocrit (OR, 2.1), low thrombocyte (OR, 5.6), low LDL (OR, 1.6), high direct bilirubin (OR, 2.0), low GFR (OR, 1.6), and high CRP (OR, 2.0). Following parameters emerged as significant independent predictors of persistent AF: EF < 60% (OR, 1.9), diabetes (OR, 2.1), COPD (OR, 1.8), previous cardiac surgery (OR, 3.1), valvular intervention (OR, 2.4), low hematocrit (OR, 1.9), low LDL (OR, 2.1), high HbA1c (OR, 2.0), and high CRP (OR, 2.7).

Conclusions

Certain parameters assessed during preoperative physical and laboratory examinations have the potential to be used as markers of POAF.

Atrial fibrillation - Can HbA1c levels really predict the risk?

BACKGROUND

Diabetes is associated with higher mortality and worse post-operative outcomes in patients undergoing coronary artery bypass grafting and HbA1c levels have consistently been reported to be associated with adverse post-operative outcomes. However, the role of HbA1c still remains unclear with regards to the occurrence of atrial fibrillation.

METHOD

Data for the patients undergoing off-pump coronary artery bypass grafting was analysed in a retrospective fashion. Patients were divided into-those with HbA1c < 6.5% and those with HbA1c ≥ 6.5% and the incidence of atrial fibrillation observed in these two groups. We also compared patient who developed atrial fibrillation in the post-operative period and compared them with those who did not.

RESULTS

Of the 5259 patients included in the study HbA1c was <6.5 in 2808 (53.4%) patients and was ≥6.5 in 2451 (46.6%) patients; 623 (11.8%) patients in our study developed atrial fibrillation. Onset of atrial fibrillation in the post-operative period was seen most commonly 235 (38.3%) on between 24 and 48 h after the operation with more than half of them 338 (54.2%) occurring within the first 48 h. On multivariate analysis, HbA1c was not a risk factor for atrial fibrillation (odd's ratio 1.144, 95% confidence interval 0.967-1.354). Only increased age (odd's ratio 1.08; 95% confidence interval 1.069-1.091); EuroSCORE (odd's ratio 1.073; 95% confidence interval 1.048-1.099); history of recent MI (odd's ratio 0.768; 95% confidence interval 0.606-0.971) and peripheral vascular disease (odd's ratio 1.667; 95% confidence interval 1.091-2.517) were found to be independently associated with increased risk of atrial fibrillation in the post-operative period.

CONCLUSIONS

After adjusting for confounders HbA1c levels do not independently predict risk of atrial fibrillation after off-pump coronary artery bypass grafting.