Atrial fibrillation and its association with type 2 diabetes and hypertension in a Swedish community

Diabetes status, genetic susceptibility, and incident arrhythmias: A prospective cohort study of 457,151 participants

AIMS

The association of diabetes onset age and duration with incident arrhythmias remains unclear. This study evaluates the association of diabetes onset age and duration with incident arrhythmias and assesses modifications by the genetic predisposition to atrial fibrillation (AF).

METHODS

We included 457,151 participants from the UK Biobank study. Multivariable Cox regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) were used for the association between diabetes status, genetic predisposition, and risk of incident arrhythmias. The polygenic risk score (PRS) for AF comprised 142 single-nucleotide variants.

RESULTS

Over 12 years of follow-up, we documented 23,518 AF, 9079 bradyarrhythmia, 9280 conduction system diseases, 3358 supraventricular arrhythmias, and 3095 ventricular arrhythmias. Compared with non-diabetes, the risks of AF increased by 19%, 25%, and 36% for those with diabetes durations <5, 5-9, and ≥10 years, respectively. After multivariate adjustment, with the increase in diabetes onset age, the HRs of outcomes were gradually attenuated. The multivariable-adjusted HRs (95% CI) of diabetes for AF were 1.46 (1.24-1.71) in early middle age (<55 years), 1.21 (1.12-1.30) in late middle age (55-64 years), and 1.15 (1.06-1.24) in the elderly population (≥65 years). A significant interaction between diabetes status and AF-PRS for incident AF was observed (P for interaction <0.001). The same trends were observed for the other arrhythmias.

CONCLUSIONS

Diabetes was associated with higher risks of incident arrhythmias, and younger age at onset of diabetes was significantly associated with higher risk of subsequent arrhythmias.

Assessing the association between triglyceride-glucose index and atrial fibrillation: a systematic review and meta-analysis

BACKGROUND

An essential relationship between insulin resistance (IR) and atrial fibrillation (AF) has been demonstrated. Among the methods used to assess IR, the triglyceride-glucose (TyG) index is the more straightforward, dimensionless, and low-cost tool. However, the possible usage of this index in clinical practice to predict and diagnose AF has yet to be determined and consolidated.

OBJECTIVE AND RATIONALE

Herein, we performed a systematic review and meta-analysis to assess the association between the TyG index and AF.

METHODS

Databases (PubMed, Embase, Scopus, and Web of Science) were systematically searched for studies evaluating the TyG index in AF. The inclusion criteria were observational studies investigating AF and TyG index correlation in individuals older than 18 years, while preclinical studies and those without the relevant data were excluded. Random effect meta-analyses comparing TyG levels between AF and non-AF cases, AF recurrence after radiofrequency ablation, and post-procedural AF were performed using standardized mean differences (SMD) with their matching 95% confidence intervals (CIs).

RESULTS

Our screening identified nine studies to be analyzed, including 6,171 participants including 886 with AF. The meta-analysis demonstrated that the TyG index resulted higher in patients with AF than non-AF counterparts (SMD 1.23, 95% CI 0.71 to 1.75, I2 98%, P < 0.001). Subgroup analysis showed the same results for post-procedure AF (SMD 0.99, 95% CI 0.78 to 1.20, I2 10%, P < 0.001) and post-ablation AF (SMD 1.25, 95% CI 1.07 to 1.43, I2 46%, P < 0.001), while no difference was found in population-based cohorts (SMD 1.45, 95% CI - 0.41 to 3.31, I2 100%, P = 0.13). Publication year (P = 0.036) and sample size (P = 0.003) showed significant associations with the effect size, using multivariable meta-regression.

CONCLUSION

The TyG index is an easy-to-measure surrogate marker of IR in patients with AF. Further clinical studies are warranted to demonstrate its ability for routine clinical use and as a screening tool.

Association of adiponectin gene expression with atrial fibrillation in a Pakistani populace

Adiponectin, an adipocytokine produced and secreted by adipose tissue, has anti-diabetic, anti-atherogenic, and anti-inflammatory properties. This case-control study was aimed to assess the expression and serum levels of adiponectin in subject suffereing from atrial fibrillation (AF). The study's subjects (n = 690) were enrolled from the Punjab Institute of Cardiology, Lahore and were grouped into control, AF without Metabolic syndrome (MetS), and AF with MetS groups. Along with the collection of demographic data, an analysis of adiponectin and biochemical parameters were performed. A highly significant difference in serum levels of adiponectin was observed among the control, AF without MetS, and AF with MetS groups (61.61 ± 45.30 ng/ml, 37.20 ± 19.46 ng/ml, 63.78 ± 61.69 ng/ml). The expression analysis of adiponectin was decreased (n-fold = ̴ 0.30) in AF without MetS group as compared to control group (n-fold =  ~ 1.16) but increased in AF with MetS group (n-fold = ̴ 6.26). The correlation analysis revealed a highly significant positive relationship between the expression of the adiponectin gene with waist-to-hip ratio (WHR) in AF without MetS group. Whereas, serum adiponectin was negatively related to serum triglycerides (TG) in AF with MetS group. In multiple regression analysis using adiponectin expression as the dependent variable, WHR was a determinant in AF without MetS. Whereas, when serum adiponectin was used as the dependent variable, serum TG was the determinant in group AF with MetS. The present study implicates that decreased expression and serum levels of adiponectin were associated with the development of AF in which WHR and serum TG also contributed towards the onset of atrial fibrillation.

The Synergistic Relationship Between Atrial Fibrillation and Diabetes Mellitus: Implications for Cardiovascular and Metabolic Health

Type 2 diabetes mellitus (T2DM) and atrial fibrillation (AF) are widespread chronic conditions that profoundly impact public health. While the intricate mechanisms linking these two diseases remain incompletely understood, this review sets out to comprehensively analyze the current evidence about their pathophysiology, epidemiology, diagnosis, prognosis, and treatment. We reveal that T2DM can influence the electrical and structural properties of the atria through multiple pathways, including oxidative stress, inflammation, fibrosis, connexin remodeling, glycemic variability, and autonomic dysfunction. Moreover, it significantly influences AF's clinical course, elevating the risk of heart failure, stroke, and cardiovascular mortality. Our review also explores treatment options for individuals with T2DM and AF, encompassing antidiabetic and antiarrhythmic drugs and non-pharmacological interventions, such as cardioversion catheter ablation and direct current cardioversion. This review depicts an insight into the clinical interplay between T2DM and AF. It deepens our comprehension of the fundamental mechanisms, potential therapeutic interventions, and their implications for patient care. This comprehensive resource benefits researchers seeking to deepen their knowledge in this domain. Ultimately, our findings pave the way for more effective strategies in managing AF within the context of T2DM.

Increased Left Atrial Stiffness is Significantly Associated with Paroxysmal Atrial Fibrillation in Diabetic Patients

Purpose

Atrial fibrillation (AF) and diabetes mellitus (DM) are common pathogenic diseases. Diabetes is an independent risk factor for AF, and coexisting AF is a risk factor for the diabetic pa-tient's progression. The purpose of this study was to see if two-dimensional-speckle tracking echocardiography (2D-STE) might provide valuable criteria for determining the risk of AF in diabetic patients.

Patients and Methods

This retrospective study compared 30 adult diabetic patients with documented paroxysmal atrial fibrillation (PAF) with 30 age- and sex-matched diabetic patients without PAF. Inclusion criteria were: age ≥18 years, sinus rhythm, diabetes mellitus type 2, and the ability to sign the informed consent. Exclusion criteria included: moderate or severe valvular disease, previous myocardial infarction, left ventricular ejection fraction (LVEF) <50%, congenital heart disease, a history of cardiac surgery, paced atrial or ventricular rhythm, inadequate echocardiography imaging. The medical history, clinical, biochemical data and the results of the transthoracic cardiac ultrasound examination were registered during their evaluation at the outpatients cardiology clinics.

Results

The mean age of the patients was 62.5±1.7 years, 60% were men. Diabetic patients who experienced PAF episodes demonstrated significantly impaired left atrial (LA) deformation patterns, with decreased LA strains and increased LA stiffness (p < 0.05).

Conclusion

The present study demonstrates that LA strains and LA stiffness are significantly associated with the occurrence of PAF in diabetic patients. As 2D-STE of the LA is more sensitive than routine echocardiographic examination, it should be performed in patients suspected of being suffering from PAF.

Accumulated hypertension burden on atrial fibrillation risk in diabetes mellitus: a nationwide population study

BACKGROUND

Patients with diabetes mellitus have an increased risk of incident atrial fibrillation (AF). The effect of accumulated hypertension burden is a less well-known modifiable risk factor. We explored the relationship between accumulated hypertension burden and incident AF in these patients.

METHODS

We evaluated data for 526,384 patients with diabetes who underwent three consecutive health examinations, between 2009 and 2012, from the Korean National Health Insurance Service. Hypertension burden was calculated by assigning points to each stage of hypertension in each health examination: 1 for stage 1 hypertension (systolic blood pressure [SBP] 130-139 mmHg; diastolic blood pressure [DBP] 80-89 mmHg); 2 for stage 2 (SBP 140-159 mmHg and DBP 90-99 mmHg); and 3 for stage 3 (SBP ≥ 160 mmHg or DBP ≥ 100 mmHg). Patients were categorized into 10 hypertensive burden groups (0-9). Groups 1-9 were then clustered into 1-3, 4-6, and 7-9.

RESULTS

During a mean follow-up duration of 6.7 ± 1.7 years, AF was newly diagnosed in 18,561 (3.5%) patients. Compared to patients with hypertension burden 0, those with burden 1 to 9 showed a progressively increasing risk of incident AF: 6%, 11%, 16%, 24%, 28%, 41%, 46%, 57%, and 67% respectively. Clusters 1-3, 4-6, and 7-9 showed increased risks by 10%, 26%, and 45%, respectively, when compared to a hypertension burden of 0.

CONCLUSIONS

Accumulated hypertension burden was associated with an increased risk of incident AF in patients with diabetes. Strict BP control should be emphasized for these patients.

[Rhythm and metabolic control]

Diabetes mellitus and atrial fibrillation show a steady increase in their prevalence. Diabetes mellitus is a relevant risk factor for the development and maintenance of atrial fibrillation, which should not be underestimated. Fluctuations in blood glucose levels occurring in diabetes, inflammatory processes and oxidative stress lead to structural, electromechanical, electrical and autonomic remodelling processes in the myocardium that promote atrial fibrillation. When atrial fibrillation and diabetes mellitus coincide, this is often associated with more pronounced symptoms, lower quality of life, more frequent hospitalization and a higher mortality rate. Can early and consistent euglycemic blood glucose monitoring effectively influence atrial remodelling processes, cardiovascular end points and the occurrence of atrial fibrillation? Are there new and combined drug treatment approaches for diabetes mellitus and atrial fibrillation? What ablation strategy should be adopted for the interventional treatment of atrial fibrillation in patients with diabetes mellitus? This review article attempts to find answers to these questions.

Pathophysiological aspects of insulin resistance in Atrial Fibrillation: novel therapeutic approaches

Background

Insulin resistance is associated with metabolic disorders including diabetes, obesity, hypertension, and inflammation which are the risk factors for Atrial Fibrillation. Many studies have reported that type 2 diabetes and AF are related and also their prevalence is increasing globally. Moreover, insulin resistance begins the type 2 diabetes.

Main body

This review explains the pathophysiological aspects of insulin resistance in AF patients and discusses the drugs that are used to manage insulin resistance including Biguanides (metformin), thiazolidinediones (TZDs) [Pioglitazone, rosiglitazone], Sodium-glucose cotransporter 2 (SGLT2) inhibitors, Concentrated Insulin Products, Dipeptidyl peptidase-4 (DPP-4) Inhibitors, Glucagon-like peptide 1 (GLP-1) receptor Agonists, Pramlintide, Sulfonylureas, Meglitinides, α-Glucosidase Inhibitors, Colesevelam, Bromocriptine. This review will highlight a few major drugs that played a significant role in AF patients. For this purpose, many databases were used for reviewing the literature and keywords are used such as Insulin Resistance, Pathophysiology, Atrial Fibrillation, and Drugs.

Conclusion

This review article concludes that insulin resistance is related to AF. It also provides an outlook on the recent pathophysiological aspects of insulin resistance in AF; however, more studies are needed to clarify the management of insulin resistance in AF patients to prevent the development of type 2 diabetes.

Screening for Atrial Fibrillation in Community and Primary CareSettings: A Scoping Review

Background

Atrial Fibrillation (AF) is the most common tachyarrhythmia and is associated with increased risk of stroke, morbidity and mortality. AF is responsible for up to a quarter of all strokes and is often asymptomatic until a stroke occurs.Screening for AF is a valuable approach to reduce the burden of stroke in the population.

Objectives

The motivation for this review was to synthesise and appraise the evidence for screening for AF in the community. The aims of this scoping review are 1). To describe the prevalence of newly diagnosed AF in screening programmes 2). Identify which techniques/ tools are employed for AF screening 3). To describe the setting and personnel involved in screening for AF.

Eligibility Criteria

All forms of AF screening in adults (≥18 years) in primary and community care settings.

Methods

This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping reviews (PRISMA-ScR).

Results

Fifty-nine papers were included; most were cross-sectional studies (n=41) and RCTs (n=7). Prevalence of AF ranged from 0-34.5%. Screening tools and techniquesincluded the 12-lead ECG (n=33), the 1-lead ECG smartphone based Alivecor® (n=14) and pulse palpation (n=12). Studies were undertaken in community settings (n=30) or in urban/rural primary care (n=28). Personnel collecting research data were in the main members of the research team (n=31), GPs (n=16), practice nurses (n=10), participants (n=8) and pharmacists (n=4).

Conclusion

Prevalence of AF increased with advancing age. AF screening should target individuals at greatest risk of the condition including older adults≥65 years of age. Emerging novel technologies may increase the accessibility of AF screening in community and home settings. There is a need for high quality research to investigate AF prevalence and establish accuracy and validity for traditional versus novel screening tools used to screen for AF.

Medical therapies for prevention of cardiovascular and renal events in patients with atrial fibrillation and diabetes mellitus

Atrial fibrillation (AF), type 2 diabetes mellitus (DM), and chronic kidney disease (CKD) are three global epidemics with significant effects on morbidity and mortality. Diabetes is a risk factor for AF, and a risk factor for thromboembolism, comorbidity, and mortality when AF is present. The pathophysiology of diabetes-related AF and interrelationships with cardiovascular events and renal events is not fully understood but is in part related to structural, electrical, electromechanical, and autonomic remodelling. The current practice guidelines offer limited recommendations on the management of patients with AF (or risk of AF) and diabetes with its own heterogeneity for the prevention of cardiovascular and renal events. This document discusses possible clinical approaches for these patients. In the last decade, there have been major improvements for the prevention of stroke in AF patients with direct oral anticoagulants, which are preferable to vitamin K antagonists for stroke prevention in DM. Because of the increased risk rate for several cardiovascular adverse events in diabetic patients, a similar relative risk reduction generally translates into greater absolute risk reduction in the diabetic population. Recent trials with non-insulin diabetes drugs using glucagon-like peptide-1 agonists and sodium-glucose cotransporter-2 inhibitors showed a significant reduction for the risk of major adverse cardiovascular events in patients with type 2 DM. Sodium-glucose cotransporter-2 inhibitors also showed a large reduction in hospitalization for heart failure and renal events, which need to be more completely evaluated in patients with AF. Mechanisms, risks, and optimal management of AF patients with DM who have or are under risk of developing heart failure or CKD are also discussed in this document. The benefits of medical therapies for these patients still need to be put into perspective, and gaps in evidence on some of these issues are likely to be addressed in future years.

Predictive model for atrial fibrillation in hypertensive diabetic patients

BACKGROUND

Several scores to identify patients at high risk of suffering atrial fibrillation have been developed. Their applicability in hypertensive diabetic patients, however, remains uncertain. Our aim is to develop and validate a diagnostic predictive model to calculate the risk of developing atrial fibrillation at five years in a hypertensive diabetic population.

METHODS

The derivation cohort consisted of patients with both hypertension and diabetes attended in any of the 52 primary healthcare centres of Barcelona; the validation cohort came from the 11 primary healthcare centres of Terres de l'Ebre (Catalonia South) from January 2013 to December 2017. Multivariable Cox regression identified clinical risk factors associated with the development of atrial fibrillation. The overall performance, discrimination and calibration of the model were carried out.

RESULTS

The derivation data set comprised 54 575 patients. The atrial fibrillation rate incidence was 15.3 per 1000 person/year. A 5-year predictive model included age, male gender, overweight, heart failure, valvular heart disease, peripheral vascular disease, chronic kidney disease, number of antihypertensive drugs, systolic and diastolic blood pressure, heart rate, thromboembolism, stroke and previous history of myocardial infarction. The discrimination of the model was good (c-index = 0.692; 95% confidence interval, 0.684-0.700), and calibration was adequate. In the validation cohort, the discrimination was lower (c-index = 0.670).

CONCLUSIONS

The model accurately predicts future atrial fibrillation in a population with both diabetes and hypertension. Early detection allows the prevention of possible complications arising from this disease.

The Effect of Diabetes Mellitus on the Recurrence of Atrial Fibrillation after Ablation

Diabetes mellitus (DM) plays a crucial role in the regulation of atrial fibrillation (AF). This study aimed to evaluate the outcome of pulmonary vein isolation (PVI) using a single-shot device in patients with AF and DM. A total of 531 consecutive patients undergoing initial cryoballoon (CB)-guided PVI were evaluated. Two hundred eighty-one patients (53%) suffered from paroxysmal AF (PAF; mean age 51 ± 23.2 years, 26% female), 250 patients (48%) from persistent AF (PERS; 64 ± 10.0 years old, 30% female) and 80 patients (15%) were diagnosed with coincidental DM (68 ± 19.6 years old, 30% female). Follow-up visits were performed at 3, 6 and 12 months including 7-day Holter ECGs. Primary endpoint was the first documented recurrence of atrial tachyarrhythmia. AF recurrence occurred in 26% (140 patients). PAF patients with DM presented with a significantly higher risk for arrhythmia recurrence (Kaplan Meier analysis; Log rank p < 0.001 *). Multivariate analyses found DM to be an independent predictor (IP) for AF recurrence (p = 0.009 *, hazard ratio (HR) 4.363, confidence interval (CI) 1.456–13.074). In PERS, DM was associated with a 43% increase in AF recurrence (p = 0.320, HR 1.427, CI 0.707–2.879). DM has relevant effects on AF recurrence after PVI-only ablation approaches for AF. Major differences were observed in PAF as DM seems to favor the development of individual arrhythmia substrate, which is usually not yet present in PAF. In PERS, DM effects are less pronounced as individual fibrosis has already developed. Thus, personalized paths addressing individual arrhythmia substrates are needed in this specific cohort of patients.

MiR-21-3p Inhibits Adipose Browning by Targeting FGFR1 and Aggravates Atrial Fibrosis in Diabetes

A relationship between excess epicardial adipose tissue (EAT) and the risk of atrial fibrillation (AF) has been reported. Browning of EAT may be a novel approach for the prevention or treatment of AF by attenuating atrial fibrosis. Previous studies have identified microRNA-21 (miR-21) as a regulatory factor in atrial fibrosis. The present study examined the role of different subtypes of miR-21 in adipose browning and atrial fibrosis under hyperglycemic conditions. Wild type and miR-21 knockout C57BL/6 mice were used to establish a diabetic model via intraperitoneal injection of streptozotocin. A coculture model of atrial fibroblasts and adipocytes was also established. We identified miR-21-3p as a key regulator that controls adipocyte browning and participates in atrial fibrosis under hyperglycemic conditions. Moreover, fibroblast growth factor receptor (FGFR) 1, a direct target of miR-21-3p, decreased in this setting and controlled adipose browning. Gain and loss-of-function experiments identified a regulatory pathway in adipocytes involving miR-21a-3p, FGFR1, FGF21, and PPARγ that regulated adipocyte browning and participated in hyperglycemia-induced atrial fibrosis. Modulation of this signaling pathway may provide a therapeutic option for the prevention and treatment of atrial fibrosis or AF in DM.

Silent atrial fibrillation detected by home-monitoring: Cardiovascular disease and stroke prevention in patients with diabetes

OBJECTIVE

Patients with silent and undiagnosed paroxysmal atrial fibrillation and flutter (AF) have increased risk of ischemic stroke. Patients with diabetes have a higher risk of both AF and ischemic stroke compared to patients without diabetes. Our aim was to investigate the prevalence of silent AF in patients with diabetes in an outpatient cohort and to identify the possible risk factors associated with AF.

RESEARCH DESIGN AND METHODS

This prospective observational study was performed in the outpatient diabetes clinic at a single University Hospital. We included 217 patients with type 1 or type 2 diabetes with at least one additional risk factor from the CHA₂DS₂VASc Score for Stroke Risk Assessment in Atrial Fibrillation. The primary outcome was prevalence of AF, with a duration of at least 30 s, recorded by a seven-day home-monitor, external loop recorder (ELR) in comparison to a standard resting ECG. Seventeen patients were excluded due to premature removal of the device.

RESULTS

In the final cohort of 200 patients the majority were male (58.5%) with a mean age of 66 ± 0.7 years. The mean BMI was 29 ± 6 and patients had a mean diabetes history of 23 ± 14 years with the majority diagnosed with type 2 diabetes (59%). Comorbidity was common with hypertension in 86%, and dyslipidemia in 80%. The total prevalence of silent AF [n = 20 (10%)] or flutter [n = 1 (0.5%)] was 10.5% using the ELR compared to a 0.0% detection-rate in the standard ECG method (p < 0.001). Higher age, male gender, albuminuria, and elevated systolic blood pressure were associated with AF in univariate analyses, but only age [OR 1.14 (95% CI = 1.00-2.04) (p = 0.048)], male gender [OR 4.9 (95% CI = 1.30-18.65) (p = 0.019)] and albuminuria [OR 2.7 (95% CI =1.08-6.98) (p = 0.034) were independently associated with AF. Mean CHA₂DS₂VASc Score was ≥2 (4.1, SD ± 1.6), and patients with AF were referred to further cardiac evaluation.

CONCLUSION

Undiagnosed, silent AF is common in high-risk cohort with a long history of diabetes followed in a University Hospital outpatient clinic. Non-invasive monitoring with ELR enhances detection of AF and identifies candidates for early anticoagulation treatment with the possible effect of stroke prevention.

Macrovascular Complications of Type 2 Diabetes Mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) has emerged as a pandemic. It has different complications, both microvascular and macrovascular.

OBJECTIVE

The purpose of this review is to summarize the different types of macrovascular complications associated with T2DM.

METHODS

A comprehensive review of the literature was performed to identify clinical studies, which determine the macrovascular complications associated with T2DM.

RESULTS

Macrovascular complications of T2DM include coronary heart disease, cardiomyopathy, arrhythmias and sudden death, cerebrovascular disease and peripheral artery disease. Cardiovascular disease is the primary cause of death in diabetic patients. Many clinical studies have shown a connection between T2DM and vascular disease, but almost always other risk factors are present in diabetic patients, such as hypertension, obesity and dyslipidaemia.

CONCLUSION

T2DM causes a variety of macrovascular complications through different pathogenetic pathways that include hyperglycaemia and insulin resistance. The association between T2DM and cardiovascular disease is clear, but we need more clinical studies in order to identify the pure effect of T2DM.

[Clinical characteristics and quality assessment of the treatment of patients with chronic heart failure with diabetes mellitus]

AIM

A study of the clinical and instrumental characteristics and quality of treatment of patients with chronic heart failure (CHF) with diabetes mellitus.

MATERIALS AND METHODS

The study was conducted by using the CHF register method, which is a computer program with remote access, which allows on-line data collection on patients who have been examined and treated in primary care and in hospitals. The study included 8272 patients with CHF IIIV FC (functional class) (New York Heart Association NYHA); among them 62% of patients were treated in hospital.

RESULTS

The study showed that the frequency of diabetes was 21%. The main causes of CHF in diabetic patients are coronary artery disease, myocardial infarction (in anamnesis) and hypertension. These patients are more often diagnosed with III and IV CHF FC according to (NYHA) and retained LV (left ventricular) ejection fraction. The reduced ejection fraction was observed in 6.8% of cases, and the frequency of the intermediate LV was significantly higher than among patients with CHF and with diabetes and accounted for 18.9%. At patients with CHF with diabetes in comparison with patients with CHF without diabetes, atherosclerosis of the peripheral arteries, stroke (in anamnesis) and chronic kidney disease of stage III and IV were significantly more common.

CONCLUSION

Under the treatment, patients with CHF with diabetes have higher levels of SBP (systolic blood pressure), lipids and glucose in the blood plasma, indicating a lack of quality of treatment and, accordingly, the doctors are not optimally performing the clinical guidelines on treating this category of patients.

Early detection of left atrial and bi-ventricular myocardial strain abnormalities by MRI feature tracking in normotensive or hypertensive T2DM patients with preserved LV function

BACKGROUND

Previous studies have found that impaired global myocardial systolic strain is associated with cardiovascular events in T2DM patients. However, the effect of hypertension (HT) on left atrial (LA), right ventricular (RV) and left ventricular (LV) myocardial deformation in hypertensive T2DM patients has not been fully studied by cardiac magnetic resonance feature tracking (CMR-FT). Our aim was to assess LA, RV and LV strain in T2DM patients with T2DM-HT and without hypertension using CMR-FT and to determine the underlying relationships with clinical parameters.

METHODS

A total of 27 T2DM patients, 23 T2DM-HT patients and 31 controls were studied. LA, LV and RV strain was evaluated using CMR-FT. The clinical and biochemical parameters of the patients were collected.

RESULTS

The T2DM patients had reduced LA global circumferential strain (LAGCS), radial strain (LAGRS), longitudinal strain (LAGLS) and right ventricular longitudinal strain (RVGLS) compared with the controls (LAGCS: 27.2 ± 2.1% vs 33.5 ± 2.4%; LAGRS: - 28.6 ± 1.1% vs - 31.9 ± 1.3%; LAGLS: 24.3 ± 1.3% vs 31.4 ± 1.5; RVGLS: - 21.4 ± 1.2% vs - 26.3 ± 1.1%, p < 0.05 for all). The T2DM-HT patients had greater LAGCS, LAGRS and LAGLS than the T2DM patients (LAGCS: 40.4 ± 3.8% vs 27.2 ± 2.1%; LAGRS: - 36.8 ± 2.0% vs - 28.6 ± 1.1%; LAGLS: 32.3 ± 2.4% vs 24.3 ± 1.3%, p < 0.05 for all). In the diabetic patients, LAGCS was associated with microalbuminuria levels (standardized ß = - 0.289, p = 0.021), and LAGCS, LAGRS and LAGLS were correlated with diuretic treatment (standardized ß =0.440, - 0.442, and 0.643, p < 0.05 for all).

CONCLUSIONS

CMR-FT may be considered a promising tool for the early detection of abnormal LA and RV myocardial strain. LA and RV strain values are impaired in T2DM patients. The amelioration of LA strain might be associated with hypertensive compensation or antihypertensive treatment, which requires to be confirmed in larger trials.

Risk of atrial fibrillation in persons with type 2 diabetes and the excess risk in relation to glycaemic control and renal function: a Swedish cohort study

Background

To examine the incidence of atrial fibrillation in individuals with type 2 diabetes compared with age- and sex-matched controls from the general population and its variation in relation to glycaemic control and renal function.

Methods

A total of 421,855 patients with type 2 diabetes from the Swedish National Diabetes Registry and 2,131,223 controls from the Swedish Population Registry, matched for age, sex and county, were included and followed from January 1, 2001 to December 31, 2013.

Results

Overall, 8.9% of individuals with type 2 diabetes and 7.0% of controls were diagnosed with atrial fibrillation during follow-up, unadjusted incidence risk ratio (IRR) 1.35 (95% 1.33–1.36). Women < 55 years old with type 2 diabetes had an IRR of 2.36 (95% CI 2.10–2.66), in relation to controls, whereas the corresponding value for men < 55 years old with type 2 diabetes was IRR 1.78 (95% CI 1.67–1.90). In the fully adjusted Cox regression, the risk of type 2 diabetes on incident atrial fibrillation was 28% greater vs controls, hazard ratio (HR) 1.28 (95% CI 1.26–1.30), p < 0.0001. The excess risk of atrial fibrillation in individuals with type 2 diabetes increased with worsening glycaemic control and renal complications. For individuals with HbA1c ≤ 6.9% (≤ 52 mmol/mol) and normoalbuminuria the excess risk vs controls was still increased, adjusted HR 1.16 (95% CI 1.14–1.19); p < 0.0001.

Conclusions

Individuals with type 2 diabetes had an overall 35% higher risk of atrial fibrillation compared to age- and sex-matched controls from the general population. The excess risk for atrial fibrillation increased with renal complications or with poor glycaemic control. Individuals with type 2 diabetes with good glycaemic control and normoalbuminuria had slightly increased risk.

Type 2 Diabetes, Atrial Fibrillation, and Direct Oral Anticoagulation

Type 2 diabetes (T2D) is an independent risk factor of stroke and systemic embolism in patients with atrial fibrillation (AF), and T2D patients with AF-associated stroke seem to have worse clinical outcome and higher risk of unfavorable clinical course compared to individuals without this metabolic disorder. Long-term anticoagulation is indicated in majority of T2D patients with AF to prevent adverse AF-associated embolic events. Direct oral anticoagulants (DOACs), direct oral thrombin inhibitor dabigatran, and direct oral factor Xa inhibitors, rivaroxaban, apixaban, and edoxaban, have emerged as a preferred choice for long-term prevention of stroke in AF patients offering potent and predictable anticoagulation and a favorable pharmacology with low risk of interactions. This article reviews the current data regarding the use of DOACs in individuals with T2D and AF.

Pathological Role of Advanced Glycation End Products (AGEs) and their Receptor Axis in Atrial Fibrillation

Accumulating evidence has shown that the incidence of atrial fibrillation (AF) is higher in patients with diabetes, especially those with poor glycemic control or long disease duration. Nonenzymatic glycation of amino acids of proteins, lipids, and nucleic acids has progressed under normal aging process and/or diabetic condition, which could lead to the formation and accumulation of advanced glycation end products (AGEs). AGEs not only alter the tertiary structure and physiological function of macromolecules, but also evoke inflammatory and fibrotic reactions through the interaction of cell surface receptor for AGEs (RAGE), thereby being involved in aging-related disorders. In this paper, we briefly review the association of chronic hyperglycemia and type 1 diabetes with the risk of AF and then discuss the pathological role of AGE-RAGE axis in AF and its thromboembolic complications.

Risk Factors for Atrial Fibrillation in People With Type 1 Diabetes: An Observational Cohort Study of 36,258 Patients From the Swedish National Diabetes Registry

OBJECTIVE

This study identified variables associated with increased risk of atrial fibrillation in people with type 1 diabetes.

RESEARCH DESIGN AND METHODS

We performed a cohort study of people with type 1 diabetes from the Swedish National Diabetes Registry followed up between 1 January 2001 and 31 December 2013. Median follow-up was 9.7 years (interquartile range 5.2-13.0). The association between potential risk factors and incident atrial fibrillation was investigated using adjusted Cox regression. To compare the impact of each risk factor, the gradient of risk per 1 SD was estimated.

RESULTS

In this cohort of 36,258 patients with type 1 diabetes, 749 developed atrial fibrillation during follow-up. Older age, male sex, renal complications, increased BMI and HbA_1c, coronary artery disease, heart failure, and heart valve disease increased the risk of atrial fibrillation. Age, signs of renal dysfunction with macroalbuminuria, and decreasing estimated glomerular filtration rate were associated with the highest gradient of risk for atrial fibrillation. High blood pressure, severe obesity (BMI >35 kg/m²), and elevated levels of HbA_1c (>9.6%) were associated with increased risk, but no associations were found with hyperlipidemia or smoking.

CONCLUSIONS

The most prominent risk factors for atrial fibrillation in people with type 1 diabetes were older age, cardiovascular comorbidities, and renal complications, while obesity, hypertension, and hyperglycemia had more modest affects.

Atrial fibrillation and type 2 diabetes: Prevalence, etiology, pathophysiology and effect of anti-diabetic therapies

New-onset atrial fibrillation (NAF) is increased in the type 2 diabetic patient because of the presence of the metaboli syndrome and increased sympathetic activity. This results in inflammation, endothelial dysfunction and myocardial steatosis which, in turn, lead to atrial fibrosis and dilatation. The end result is the development of structural and electrical atrial remodeling. Drugs that lower insulin resistance, particularly pioglitazone, decrease the incidence of NAF while drugs that, through hypoglycaemia, stimulate the sympathetic nervous system, insulin and secretagogues, increase the incidence of NAF. Currently there is no evidence that GLP-1 agonists, SGLT2 inhibitors and DPP-4 inhibitors either accelerate or decelerate the development of NAF.

Clinical Overview of Obesity and Diabetes Mellitus as Risk Factors for Atrial Fibrillation and Sudden Cardiac Death

The epidemics of obesity and diabetes mellitus are associated with an increased incidence of both atrial fibrillation (AF), the most common sustained arrhythmia in adults, and sudden cardiac death (SCD). Obesity and DM are known to have adverse effects on cardiac structure and function. The pathologic mechanisms are thought to involve cardiac tissue remodeling, metabolic dysregulation, inflammation, and oxidative stress. Clinical data suggest that left atrial size, epicardial fat pad thickness, and other modifiable risk factors such as hypertension, glycemic control, and obstructive sleep apnea may mediate the association with AF. Data from human atrial tissue biopsies demonstrate alterations in atrial lipid content and evidence of mitochondrial dysfunction. With respect to ventricular arrhythmias, abnormalities such as long QT syndrome, frequent premature ventricular contractions, and left ventricular hypertrophy with diastolic dysfunction are commonly observed in obese and diabetic humans. The increased risk of SCD in this population may also be related to excessive cardiac lipid deposition and insulin resistance. While nutritional interventions have had limited success, perhaps due to poor long-term compliance, weight loss and improved cardiorespiratory fitness may reduce the frequency and severity of AF.

Data Linking Diabetes Mellitus and Atrial Fibrillation-How Strong Is the Evidence? From Epidemiology and Pathophysiology to Therapeutic Implications

According to estimates, around 5% of the world population has hazel eyes. And there are about as many people with diabetes mellitus (DM). Red hair occurs naturally in up to 2% of the human population. And about as many people are estimated to have atrial fibrillation (AF). If a hazel eyed person with red hair does not surprise us, should a diabetic patient with AF? Accumulating epidemiologic data suggest, however, that the DM-AF association may be more than a simple coincidence. But, how strong is this evidence? Experimental studies bring evidence for a DM-induced atrial proarrhythmic remodelling. But how relevant are these data for the clinical setting? In this review, we aim to provide a critical analysis of the existing clinical and experimental, epidemiologic, and mechanistic data that bridge DM and AF, we emphasize a number of questions that remain to be answered, and we identify hotspots for future research. The therapeutic implications of the DM-AF coexistence are also discussed, with a focus on rhythm control and on conventional and DM-specific upstream therapies for AF management.

Cardiovascular outcome in type 2 diabetes and atrial fibrillation

Diabetes is an independent risk factor for atrial fibrillation (AF). Frequently, it is part of the metabolic syndrome cluster, which includes obesity and hypertension that are independently associated with AF. The risk appears to be higher with longer duration of diabetes and inadequate glycemic control. Patients with diabetes and AF have a substantially increased risk of death and serious cardiovascular complications compared with those in sinus rhythm. Conversely, good metabolic control appears to be associated with maintenance of rhythm after successful therapeutic conversion to sinus rhythm by catheter ablation or electrical cardioconversion of AF. AF puts patients with type 2 diabetes at a high risk of cardiovascular complications and death, which could be successfully addressed by new classes of antidiabetic agents such as incretin analogues or sglt-2 inhibitors. Thus, a diagnostic strategy that addresses the increased risk for AF is urgently recommended, in addition to diabetes monitoring in routine outpatient practice. In order to prevent thromboembolic complications, which frequently determine the prognosis for this patient population, appropriate anticoagulation remains the mainstay of therapy, whereas the prognostic value of reinstalling sinus rhythm awaits further evidence.

Dysregulation of insulin-sensitive glucose transporters during insulin resistance-induced atrial fibrillation

Diabetes has been identified as major risk factor for atrial fibrillation (AF). Although glucose and insulin disturbances during diabetes may affect atrial function, little is known about the potential pathogenic role of glucose metabolism during AF. Glucose transport into the cell via glucose transporters (GLUTs) is the rate-limiting step of glucose utilization. Although GLUT4 is the major isoform, GLUT8 has emerged as a novel insulin-sensitive cardiac isoform. We hypothesized that atrial glucose homeostasis will be impaired during insulin resistance-induced AF. AF was induced by transesophageal atrial pacing in healthy mice and following a long-term high-fat-diet-induced insulin resistance. Active cell surface GLUT content was measured using the biotinylated photolabeling assay in the intact perfused heart. Atrial fibrosis, advanced glycation end products (AGEs) and glycogen were measured in the atria using histological analyses. Animals fed a high-fat-diet were obese and mildly hyperglycemic, and developed insulin resistance compared to controls. Insulin-resistant (IR) animals demonstrated an increased vulnerability to induced AF, as well as spontaneous AF. Insulin-stimulated translocation of GLUT4 and GLUT8 was down-regulated in the atria of IR animals, as well as their total protein expression. We also reported the absence of fibrosis, glycogen and AGE accumulation in the atria of IR animals. In the absence of structural remodeling and atrial fibrosis, these data suggest that insulin signaling dysregulation, resulting in impaired glucose transport in the atria, could provide a metabolic arrhythmogenic substrate and be a novel early pathogenic factor of AF.

Considerations and treatment options for patients with comorbid atrial fibrillation and diabetes mellitus

INTRODUCTION

Atrial fibrillation (AF) and diabetes mellitus (DM) are common worldwide and their incidence is increasing, representing a significant public health and economic burden as well as an increase in individual increased morbidity and mortality risk profiles. Both conditions are closely related, as patients with DM are at increased risk of incident AF, and AF patients with DM are at higher risk of cardiovascular events compared to non-AF patients. Areas covered: This review article aims to provide an overview of the current evidence linking DM and AF, as well as the impact of obesity, weight loss and stroke on these coexisting conditions. Second, the effects of new oral anti hyperglycaemic medications on cardiovascular risk will be considered. Expert opinion: In conclusion, coexisting AF and DM represent a high risk population of patients requiring aggressive risk factor identification and treatment optimisation. The multifactorial interplay between these conditions requires individual assessment of patient risk profiles with the aim of minimising the impact of each modifiable risk factor.

Early impairment in left ventricular longitudinal systolic function is associated with an increased risk of incident atrial fibrillation in patients with type 2 diabetes

AIMS

It is known that type 2 diabetic patients are at high risk of atrial fibrillation (AF). However, the early echocardiographic determinants of AF vulnerability in this patient population remain poorly known.

METHODS

We followed-up for 2years a sample of 180 consecutive outpatients with type 2 diabetes, who were free from AF and ischemic heart disease at baseline. All patients underwent a baseline echocardiographic-Doppler evaluation with tissue Doppler and 2-D strain analysis. Standard electrocardiograms were performed twice per year, and a diagnosis of incident AF was confirmed in affected patients by a single cardiologist.

RESULTS

Over the 2-year follow-up period, 14 (7.8%) patients developed incident AF. In univariate analyses, echocardiographic predictors of new-onset AF were greater indexed cardiac mass, larger indexed left atrial volume (LAVI), lower global longitudinal strain (LS_SYS), lower global diastolic strain rate during early phase of diastole (SR_E), lower global diastolic strain rate during late phase of diastole (SR_L), and higher E/SR_E ratio. Multivariate logistic regression analysis showed that lower LS_SYS remained the only significant predictor of new-onset AF (adjusted-odds ratio 1.63, 95%CI 1.17-2.27; p<0.005) after adjustment for age, sex, diabetes duration, indexed cardiac mass and LAVI. Results were unchanged even after adjustment for body mass index, hypertension and glycemic control.

CONCLUSIONS

This is the first prospective study to show that early LS_SYS impairment independently predicts the risk of new-onset AF in type 2 diabetic patients with preserved ejection fraction and without ischemic heart disease. Future larger prospective studies are needed to confirm these findings.

Evaluating the benefits of home-based management of atrial fibrillation: current perspectives

Atrial fibrillation (AF) is the most common arrhythmia worldwide, leading to an extensive public health and economic burden. The increasing incidence and prevalence of AF is due to the advancing age of the population, structural heart disease, hypertension, diabetes, and thyroid disease. The majority of costs associated with AF have been attributed to the cost of hospitalization. In order to minimize costs and decrease hospitalizations, counseling on modifiable risk factors contributing to AF has been strongly emphasized. With the release of novel oral anticoagulants bypassing the need for anticoagulant bridging or laboratory monitoring, post-discharge nurse-led home intervention, and novel methods of heart rate monitoring, home-based AF management has reached a new level of ease and sophistication. In this review, we aimed to review modifiable risk factors for AF and various methods of home-based management of AF, along with their benefits.

Impact of the Metabolic Syndrome on Atrial Size in Patients With New-Onset Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia, and it is strongly related to atrial enlargement. Metabolic syndrome (MetSyn) is associated with increased cardiovascular morbility and mortality. However, the impact of the MetSyn on cardiac arrhythmias is poorly elucidated. The aim of this study was to compare atrial dimensions in patients suffering from nonvalvular paroxysmal AF, with and without MetSyn, trying to identify structural differences that could favor the occurrence of this arrhythmia. The study population consisted of 60 patients who presented with at least 1 episode of paroxysmal AF. From these, 26 patients fulfilled the criteria of the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) definition of MetSyn, while the remaining 34 patients did not. Left atrial size was assessed by 2-dimensional echocardiography. Patients with MetSyn had a mean atrial size of 46.2 ∓4.3 mm and those without MetSyn had a mean atrial size of 41.6 ∓1.9 mm, p<0.011. MetSyn may favor the occurrence of paroxysmal AF by increasing atrial size. This concept deserves more research.

No Additional Effect of DPP-4 Inhibitor on Preventing Atrial Fibrosis in Streptozotocin-Induced Diabetic Rat as Compared With Sulfonylurea

Chronic inflammation is known to occur in diabetes mellitus (DM) and contributes to atrial fibrosis, possible substrates for atrial fibrillation. We tested the hypothesis that dipeptidyl peptidase (DPP)-4 inhibitors prevent the formation of atrial fibrosis through their anti-inflammatory activity, beyond the effects of controlling blood glucose.DM models obtained by administration of streptozotocin (STZ) were divided into 3 groups: with PKF275-055, a DPP-4 inhibitor in group D, glibenclamide in group SU, and no additional drug in group P. At 8 weeks after STZ administration, the heart was subjected to Masson trichrome staining and immunohistochemistry with anti-ED2, ED3, and smooth muscle actin antibody.The % area of fibrosis in atria of group P accounted for 14.7% ± 4.1%, showing a significant increase in fibrosis when compared with the control group. In group SU, the % area accounted for 7.9% ± 2.9%, indicating significant deceased fibrosis by sulfonylurea. Meanwhile, we could not find significant differences in group D when compared to group P or group SU. While ED3-positive cells increased in group P (1.12% ± 0.24%), they were significantly decreased in groups D and SU (0.41% ± 0.22% and 0.55% ± 0.29%, respectively). Between group D and SU, however, there were no significant differences in the amount of cells positive to ED2, ED3, and smooth muscle actin antibodies.In STZ-induced DM rats, administration of sulfonylurea and DPP-4 inhibitors inhibited inflammation and fibrosis of the atria. However, no significant differences were observed between the 2 antidiabetic drugs.

Diabetes mellitus is an independent risk factor for atrial fibrillation in a general Chinese population

Aims/Introduction

To explore the association between atrial fibrillation (AF) and diabetes mellitus in a general Chinese population, and the influence of hypertension.

Materials and Methods

From January 2013 to August 2013, we carried out a cross‐sectional study involving 11,956 permanent residents aged ≥35 years from the general population in the Liaoning province of China (response rate 85.3%). Each participant completed a questionnaire, had a physical examination, and underwent an electrocardiogram and echocardiogram. AF was diagnosed on the basis of the electrocardiogram findings. Logistic regression analyses were carried out to estimate the associations between diabetes mellitus and AF. The associations were also analyzed in hypertensive and normotensive subgroups.

Results

There was a higher prevalence of AF in participants with diabetes mellitus than those without diabetes mellitus (1.2 vs 0.5%; P = 0.004). In the hypertensive subgroup, the prevalence of AF in participants with diabetes mellitus was significantly higher than in participants without diabetes mellitus (1.5 vs 0.6%; P = 0.008); however, the prevalences were similar in the normotensive subgroup (0.3 vs 0.4%; P = 1.000). Similar trends were present in both men and women. After adjustment for cardiovascular risk factors, the independent association between diabetes mellitus and AF remained in the total sample (odds ratio 2.33, 95% confidence interval 1.20–4.54) and hypertensive subgroup (odds ratio 3.15, 95% confidence interval 1.52–6.56), but not in the normotensive subgroup (odds ratio 0.64, 95% confidence interval 0.08–5.31).

Conclusions

Diabetes mellitus is an independent risk factor for AF in the general population in China, this association was present in total and hypertensive participants, but not in normotensive participants.

Diabetes and new-onset atrial fibrillation in a hypertensive population

AIM

The association of diabetes with new-onset atrial fibrillation (AF) remains controversial. Hypertension may partly explain the risk association ascribed to diabetes. We studied the role and characteristics of diabetes in hypertensive patients with no ischemic vascular disease.

METHODS

Records of 262,892 persons from the Information System for the Development of Research in Primary Care in Catalonia (Spain) were examined from July 2006 to December 2011. Included participants were ≥55-years-old and hypertensive with no ischemic heart disease, stroke, or peripheral artery disease. We used Cox proportional hazards regression to model incidences in the diabetic and non-diabetic subgroups of our population, and among diabetic patients, diabetes duration and pharmacological treatment, hemoglobin A1C, and body mass index.

RESULTS

New-onset AF incidence in diabetic patients was 13.3 per 1000 person-years (mean follow-up: 4.3 years). In non-diabetic patients, it was 10.4 per 1000 person-years (mean follow-up: 4.1 years). Diabetes hazard ratio (HR) for new-onset AF was 1.11 (95% confidence interval (CI): 1.06-1.16). Diabetic patients also diagnosed with obesity had an HR of 1.41 (95% CI: 1.22-1.64).

CONCLUSION

Diabetes was modestly associated with new-onset AF in hypertensive patients with no ischemic vascular disease. Among diabetic patients, only obesity reached significance in its association with this arrhythmia.

Risk factors for atrial fibrillation in type 2 diabetes: report from the Swedish National Diabetes Register (NDR)

AIMS/HYPOTHESIS

Atrial fibrillation (AF) is more frequent in patients with diabetes than in the general population. However, characteristics contributing to AF risk in diabetes remain speculative.

METHODS

Observational study of 83,162 patients with type 2 diabetes, aged 30-79 years, with no baseline AF, 17% had history of cardiovascular disease (CVD) and 3.3% history of congestive heart failure (CHF), followed up for development of AF during mean 6.8 years from 2005-2007 to 2012. A subgroup of 67,780 patients without history of CVD or CHF was also analysed.

RESULTS

Using Cox regression, cardiovascular risk factors associated with risk for AF were updated mean BMI (HR 1.31 per 5 kg/m(2)) or obesity (HR 1.51), updated mean systolic BP (SBP; HR 1.13 per 10 mmHg) or hypertension (HR 1.71), and cumulative microalbuminuria (HR 1.21), p < 0.001 for all analyses. Male sex, increasing age and height were also significant predictors. HRs were 1.76 for a history of CHF and 2.56 for in-study CHF, while 1.32 for history of CVD and 1.38 for in-study CHD (p < 0.001). Among patients without history of CVD or CHF, significant predictors were similarly BMI, SBP, and cumulative microalbuminuria and CHF. The risk of AF differed in the subgroups achieving or not achieving a target BP < 140/85 mmHg. The HRs for AF were (per 10 mmHg increase) 0.88 and 1.24, respectively.

CONCLUSIONS/INTERPRETATION

The modifiable risk factors high BP, high BMI and albuminuria were strongly associated with AF in type 2 diabetes. CVD, advancing age and height were also associated with AF in type 2 diabetes.

Diabetes mellitus and atrial remodeling: mechanisms and potential upstream therapies

Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice, and its prevalence has increasing substantially over the last decades. Recent data suggest that there is an increased risk of AF among the patients with diabetes mellitus (DM). However, the potential molecular mechanisms regarding DM-related AF and diabetic atrial remodeling are not fully understood. In this comprehensive review, we would like to summarize the potential relationship between diabetes and atrial remodeling, including structural, electrical, and autonomic remodeling. Also, some upstream therapies, such as thiazolidinediones, probucol, ACEI/ARBs, may play an important role in the prevention and treatment of AF. Therefore, large prospective randomized, controlled trials and further experimental studies should be challengingly continued.

Obesity, metabolic syndrome and risk of atrial fibrillation: a Swedish, prospective cohort study

Aim

We aimed to investigate whether different measures of obesity could similarly predict atrial fibrillation, and whether the atrial fibrillation risk associated with obesity is dependent on presence of metabolic syndrome.

Material and Methods

We performed our study in a population-based longitudinal cardiovascular study, comprising 1 924 men and 2 097 women, aged 60 years, from Stockholm. Body mass index, waist circumference, sagittal abdominal diameter and components of metabolic syndrome (systolic- and diastolic blood pressure, fasting glucose, triglycerides, high-density lipoprotein-cholesterol) were recorded at baseline. Participants were classified by their body mass index (normal weight, overweight or obese), waist circumference (normal, semi-elevated or elevated), and according to presence of metabolic syndrome. Atrial fibrillation risk was estimated by Cox proportional hazards regression models, adjusted for common atrial fibrillation risk factors, expressed as HR and 95% CI.

Results

During a mean follow-up of 13.6 years, 285 incident atrial fibrillation cases were recorded. One standard deviation increment of each obesity measure was associated with increased atrial fibrillation risk as: body mass index 1.25 (1.12 – 1.40), waist circumference 1.35 (1.19 – 1.54) and sagittal abdominal diameter 1.28 (1.14 – 1.44). Compared to normal weight subjects without metabolic syndrome, increased atrial fibrillation risk was noted for overweight subjects with metabolic syndrome, 1.67 (1.16 – 2.41), obese subjects without metabolic syndrome, 1.75 (1.11 – 2.74) and obese subjects with metabolic syndrome, 1.92 (1.34 – 2.74). Compared to subjects with normal waist circumference without metabolic syndrome, subjects with elevated waist circumference and metabolic syndrome suffered increased atrial fibrillation risk, 2.03 (1.44 – 2.87).

Conclusions

Body mass index, waist circumference and sagittal abdominal diameter could similarly predict atrial fibrillation. Obesity was associated with an increased atrial fibrillation risk regardless of metabolic syndrome, whereas overweight and elevated waist circumference was associated with increased atrial fibrillation risk only if metabolic syndrome was present.

Diabetes mellitus and atrial fibrillation: Pathophysiological mechanisms and potential upstream therapies

Diabetes mellitus (DM) represents one of the most important risk factors for atrial fibrillation (AF) while AF is a strong and independent marker of overall mortality and cardiovascular morbidity in diabetic patients. Autonomic, electrical, electromechanical, and structural remodeling, including oxidative stress, connexin remodeling and glycemic fluctuations seem to be implicated in AF pathophysiology in the setting of DM. The present review highlights the association between DM and AF, provides a comprehensive overview of the responsible pathophysiological mechanisms and briefly discusses potential upstream therapies for DM-related atrial remodeling.

Body weight and risk of atrial fibrillation in 7,169 patients with newly diagnosed type 2 diabetes; an observational study

BACKGROUND

Obesity, type 2 diabetes and atrial fibrillation (AF) are closely associated, but the underlying mechanisms are not fully understood. We aimed to explore associations between body mass index (BMI) or weight change with risk of AF in patients with type 2 diabetes.

METHODS

A total of 7,169 participations with newly diagnosed type 2 diabetes were stratified according to baseline BMI, and after a second BMI measurement within 18 months, further grouped according to relative weight change as "weight gain" (>1 BMI unit), "stable weight" (+/- 1 BMI unit) and "weight loss" (<1 BMI unit). The mean follow-up period was 4.6 years, and the risk of AF was estimated using adjusted Cox regression models.

RESULTS

Average age at diabetes diagnosis was 60 years and the patients were slightly obese (mean BMI 30.2 kg/m(2)). During follow-up, 287 patients developed incident AF, and those with overweight or obesity at baseline had 1.9-fold and 2.9-fold higher risk of AF, respectively, than those with normal BMI. The 14% of the patients with subsequent weight gain had 1.5-fold risk of AF compared with those with stable weight or weight loss.

CONCLUSIONS

In patients with newly diagnosed type 2 diabetes, baseline overweight and obesity, as well as modest weight increase during the first 18 months after diagnosis, were associated with a substantially increased risk of incident AF. Patients with type 2 diabetes may benefit from efforts to prevent weight gain in order to reduce the risk of incident AF.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01121315.

Clinical characteristics and impact of diabetes mellitus on outcomes in patients with nonvalvular atrial fibrillation

PURPOSE

Studies have shown that diabetes mellitus (DM) is a risk factor for cardiovascular disease, including atrial fibrillation (AF); however, the clinical characteristics and prognostic impact of DM in patients with nonvalvular AF have not been well understood in China.

MATERIALS AND METHODS

Included were 1644 consecutive patients with nonvalvular AF. Endpoints included all-cause mortality, cardiovascular mortality, stroke, major bleeding, and combined endpoint events (CEE) during a 1-year follow-up.

RESULTS

The prevalence of DM was 16.8% in nonvalvular AF patients. Compared with non-diabetic AF patients, diabetic AF patients were older and tended to coexist with other cardiovascular diseases. Most patients with DM (93.5%) were eligible for anticoagulation, as determined by CHADS2 scores. However, only 11.2% of patients received anticoagulation. During a 1-year follow-up, the all-cause mortality and CEE rate in the DM group were significantly higher than those of the non-DM group, while the incidence of stroke was comparable. After multivariate adjustments, DM was still an independent risk factor for 1-year all-cause mortality [hazard ratio (HR)=1.558; 95% confidence interval (CI) 1.126-2.156; p=0.007], cardiovascular mortality (HR=1.615; 95% CI 1.052-2.479; p=0.028), and CEE (HR=1.523; 95% CI 1.098-2.112; p=0.012), yet not for stroke (HR=1.119; 95% CI 0.724-1.728; p=0.614).

CONCLUSION

DM is a common morbidity coexisting with nonvalvular AF and is associated with an increased risk of 1-year all-cause mortality, cardiovascular mortality, and CEE. However, no increased risk of stroke was found during a 1-year follow-up in patients with AF and DM.