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

Estimating the burden of atrial fibrillation and atrial flutter with projection to 2050 in Iran

Atrial fibrillation (AF)/atrial flutter (AFL) is the most common cardiac tachyarrhythmia, with an increasing trend in its burden in recent years. However, the burden of AF/AFL in Iran remains unclear. This study aimed to estimate the burden of AF/AFL and its attributable risk factors from 1990 to 2019 at national and subnational levels. Using the comparative risk assessment method of the Global Burden of Disease (GBD) Study 2019, we extracted data on AF/AFL incidence, prevalence, deaths, disability-adjusted life years (DALYs), and their age-standardized rates from 1990 to 2019 and analyzed them based on by age, sex, and socio-demographic index (SDI). The percentage contribution of AF/AFL major risk factors was calculated. Moreover, the AF/AFL burden in 2050 was projected using the United Nations world population prospect data. In 2019, there were 339.1 (259.4-433.7) thousand AF/AFL patients in Iran, with 30.2 (23.2-38.5) thousand new cases, 1.7 (1.5-2) thousand deaths and 48 (37.7-60.5) thousand DALYs. Females and 50-69-year-old patients recorded a higher burden for AF/AFL; however, the increasing trend was more pronounced in males and more than 85-year-old patients. High systolic blood pressure and elevated body mass index (BMI) were the predominant attributable risk factors for AF/AFL-related deaths and DALYs. It is estimated that in 2050, the number of AF/AFL patients will increase to 1.1 million people, the incidence of AF/AFL will increase to 91 thousand patients, and the number of AF/AFL-related deaths and DALYs will surge to 7.2 and 170.8 thousand, respectively. Despite advancements in prevention and treatment, AF/AFL remains a major public health problem in Iran. Given its largely preventable and treatable nature, more cost-effective strategies are required to target modifiable risk factors, especially within susceptible age and sex groups.

Associations of obesity indices change with cardiovascular outcomes: a dose-response meta-analysis

BACKGROUND

Little is known about the degrees and shapes of associations of changes in obesity indices with cardiovascular disease (CVD) and mortality risks. We aimed to conduct a dose-response meta-analysis for the associations of changes in weight, body mass index (BMI), waist circumference (WC), waist-to-hip ratio, and waist-to-height ratio with CVD events, CVD-specific deaths, and all-cause mortality.

METHODS

We searched MEDLINE via OvidSP, Embase via OvidSP, Web of Science, CINAHL, and Scopus for articles published before January 8th, 2023. Dose-response relationships were modeled using the one-stage mixed-effects meta-analysis. Random-effects models were used to pool the relative risk (RR) and 95% confidence interval (CI).

RESULTS

We included 122 articles. Weight change was negatively associated with deaths from CVD and any cause, while WC change elevated CVD-specific mortality. Non-linear relationships also confirmed the adverse effects of increased WC on CVD-specific mortality. Additionally, gains of 5 kg in weight and 1 kg/m2 in BMI or more were associated with elevated CVD events, especially among young adults and individuals without CVD. Conversely, reductions of 5 kg in weight and 1 kg/m2 in BMI or more were associated with higher CVD-specific and all-cause deaths than increased counterparts, particularly among old adults and individuals with CVD. Similar non-linear relationships between relative changes in weight and BMI and deaths from CVD and any cause were observed.

CONCLUSIONS

The effects of changes in weight and BMI on CVD outcomes were affected by age and cardiovascular health. Tailored weight management and avoidance of increased WC should be recommended.

Obesity effect on newly diagnosed and recurrent post-ablation atrial fibrillation: a systematic review and meta-analysis

BACKGROUND AND AIMS

The role of overweight and obesity in the development of atrial fibrillation (AF) is well established; however, the differential effect on the occurrence and recurrence of AF remains uncertain. The aim of this review is to compare the effect of underweight and varying degrees of obesity on onset of AF and in recurrent post-ablation AF, and, when possible, in relation to sex.

METHODS

A systematic literature search was conducted in PubMed, Embase, and Cochrane Library from inception to January 31, 2023. Studies reporting frequency of newly-diagnosed AF and of recurrent post-ablation AF in different BMI categories, were included. 3400 records were screened and 50 met the inclusion criteria. Standardized data search and abstraction were performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Statement. Data were extracted from the manuscripts and were analyzed using a random effect model. The outcome was the occurrence of AF in population studies and in patients undergoing ablation.

RESULTS

Data from 50 studies were collected, of which 27 for newly-diagnosed AF and 23 for recurrent post-ablation AF, for a total of 15,134,939 patients, of which 15,115,181 in studies on newly-diagnosed AF and 19,758 in studies on recurrent post-ablation AF. Compared to normal weight, the increase in AF was significant (p < 0.01) for overweight, obese, and morbidly obese patients for newly-diagnosed AF, and for obese and morbidly obese patients for recurrent post-ablation AF. Newly-diagnosed AF was more frequent in obese female than obese male patients.

CONCLUSION

The effect of increased BMI was greater on the onset of AF, and obese women were more affected than men.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Impact of diabetes mellitus severity, treatment regimen and glycaemic control on atrial fibrillation prevalence in the Polish population aged ≥ 65

Diabetes mellitus (DM) is a well-known risk factor for atrial fibrillation (AF), but the mechanism(s) by which DM affects AF prevalence remains unclear. This study aims to evaluate the impact of diabetes mellitus severity (expressed as its known duration), antihyperglycemic treatment regimen and glycaemic control on AF prevalence. From the representative sample of 3014 participants (mean age 77.5, 49.1% female) from the cross-sectional NOMED-AF study, 881 participants (mean age 77.6 ± 0.25, 46.4% female) with concomitant DM were involved in the analysis. AF was screened using a telemonitoring vest for a mean of 21.9 ± 9.1 days. The mean DM duration was 12 ± 0.35 years, but no significant impact of DM timespan on AF prevalence was observed. No differences in the treatment pattern (oral medication vs insulin vs both oral + insulin) among the study population with and without AF were shown (p = 0.106). Metabolic control reflected by HbA1c levels showed no significant association with AF and silent AF prevalence (p = 0.635; p = 0.094). On multivariate analyses, age (Odds Ratio (OR) 1.35, 95%CI: 1.18-1.53, p < 0.001), p = 0.042), body mass index (BMI; OR 1.043, 95%CI: 1.01-1.08, p = 0.027) and LDL < 100 mg/dl (OR 0.64, 95%CI: 0.42-0.97, p = 0.037) were independent risk factors for AF prevalence, while age (OR 1.45, 95%CI: 1.20-1.75, p < 0.001), LDL < 100 mg/dl (OR 0.43, 95%CI 0.23-0.82, p = 0.011), use of statins (OR 0.51, 95%CI: 0.28-0.94, p = 0.031) and HbA1c ≤ 6.5 (OR 0.46, 95%CI: 0.25-0.85, p = 0.013) were associated with silent AF prevalence. Diabetes duration, diabetic treatment pattern or metabolic control per se did not significantly impact the prevalence of AF, including silent AF detected by prospective continuous monitoring. Independent predictors of AF were age, BMI and low LDL levels, with statins and HbA1c ≤ 6.5 being additional independent predictors for silent AF.Trial registration: NCT03243474.

Obesity and atrial fibrillation: a narrative review from arrhythmogenic mechanisms to clinical significance

The prevalence of obesity and atrial fibrillation (AF), which are inextricably linked, is rapidly increasing worldwide. Obesity rates are higher among patients with AF than healthy individuals. Some epidemiological data indicated that obese patients were more likely to develop AF, but others reported no significant correlation. Obesity-related hypertension, diabetes, and obstructive sleep apnea are all associated with AF. Additionally, increased epicardial fat, systemic inflammation, and oxidative stress caused by obesity can induce atrial enlargement, inflammatory activation, local myocardial fibrosis, and electrical conduction abnormalities, all of which led to AF and promoted its persistence. Weight loss reduced the risk and reversed natural progression of AF, which may be due to its anti-fibrosis and inflammation effect. However, fluctuations in weight offset the benefits of weight loss. Therefore, the importance of steady weight loss urges clinicians to incorporate weight management interventions in the treatment of patients with AF. In this review, we discuss the epidemiology of obesity and AF, summarize the mechanisms by which obesity triggers AF, and explain how weight loss improves the prognosis of AF.

Global burden of atrial fibrillation/atrial flutter and its attributable risk factors from 1990 to 2019

AIMS

The aim of this study was to estimate the global burden of atrial fibrillation (AF)/atrial flutter (AFL) and its attributable risk factors from 1990 to 2019.

METHODS AND RESULTS

The data on AF/AFL were retrieved from the Global Burden of Disease Study (GBD) 2019. Incidence, disability-adjusted life years (DALYs), and deaths were metrics used to measure AF/AFL burden. The population attributable fractions (PAFs) were used to calculate the percentage contributions of major potential risk factors to age-standardized AF/AFL death. The analysis was performed between 1990 and 2019. Globally, in 2019, there were 4.7 million [95% uncertainty interval (UI): 3.6 to 6.0] incident cases, 8.4 million (95% UI: 6.7 to 10.5) DALYs cases, and 0.32 million (95% UI: 0.27 to 0.36) deaths of AF/AFL. The burden of AF/AFL in 2019 and their temporal trends from 1990 to 2019 varied widely due to gender, Socio-Demographic Index (SDI) quintile, and geographical location. Among all potential risk factors, age-standardized AF/AFL death worldwide in 2019 were primarily attributable to high systolic blood pressure [34.0% (95% UI: 27.3 to 41.0)], followed by high body mass index [20.2% (95% UI: 11.2 to 31.2)], alcohol use [7.4% (95% UI: 5.8 to 9.0)], smoking [4.3% (95% UI: 2.9 to 5.9)], diet high in sodium [4.2% (95% UI: 0.8 to 10.5)], and lead exposure [2.3% (95% UI: 1.3 to 3.4)].

CONCLUSION

Our study showed that AF/AFL is still a major public health concern. Despite the advancements in the prevention and treatment of AF/AFL, especially in regions in the relatively SDI quintile, the burden of AF/AFL in regions in lower SDI quintile is increasing. Since AF/AFL is largely preventable and treatable, there is an urgent need to implement more cost-effective strategies and interventions to address modifiable risk factors, especially in regions with high or increased AF/AFL burden.

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.

Association of magnitude of weight loss and weight variability with mortality and major cardiovascular events among individuals with type 2 diabetes mellitus: a systematic review and meta-analysis

Background

Weight management is strongly promoted for overweight or obese patients with type 2 diabetes (T2DM) by current guidelines. However, the prognostic impact of weight loss achieved without behavioural intervention on the mortality and cardiovascular (CV) outcomes in diabetic patients is still contested.

Methods

We searched the PubMed, Embase, and Cochrane Library databases for studies that investigated the association of weight loss or weight variability with mortality and CV outcomes. Results of studies that measured weight loss by percentage weight loss from baseline and stratified it as > 10% and 5–10% or studies that computed weight variability were pooled using random effects model. Study quality was evaluated using the Newcastle–Ottawa Scale.

Results

Thirty eligible studies were included in the systematic review and 13 of these were included in the meta-analysis. Large weight loss (> 10%) was associated with increased risk of all-cause mortality (pooled hazard ratio (HR) 2.27, 95% CI 1.51–3.42), composite of major CV events (pooled HR 1.71, 95% CI 1.38–2.12) and CV mortality (pooled HR 1.50, 95% CI 1.27–1.76) among T2DM patients. Moderate weight loss showed no significant association with all-cause mortality (pooled HR 1.17, 95% CI 0.97–1.41) or CV outcomes (pooled HR 1.12, 95% CI 0.94–1.33). Weight variability was associated with high hazard of all-cause mortality (pooled HR 1.54, 95% CI 1.52–1.56).

Conclusions

Large weight loss and large fluctuations in weight are potential markers of increased risk of mortality and CV events in T2DM patients. Maintaining a stable weight may have positive impact in these patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01503-x.

Healthcare Resource Utilization and Costs of Rivaroxaban Versus Warfarin Among Nonvalvular Atrial Fibrillation Patients with Obesity and Diabetes

INTRODUCTION

Nonvalvular atrial fibrillation (NVAF) is associated with a substantial economic burden, particularly in patients with comorbid conditions. This study compared healthcare resource utilization (HRU) and costs of rivaroxaban and warfarin in patients with NVAF, obesity, and diabetes.

METHODS

A de-identified healthcare claims database was used to identify adult patients newly initiating rivaroxaban or warfarin and having at least one medical claim with a diagnosis of AF, obesity determined by validated algorithm, and at least one claim with a diagnosis of diabetes or for antidiabetic medication from December 2011 to March 2020. Propensity score matching was used to balance the treatment cohorts on the basis of demographics and baseline characteristics. All-cause and NVAF-related HRU rates and costs were compared between treatments using rate ratios, and mean cost differences were calculated on a per patient per year (PPPY) basis.

RESULTS

A total of 9999 matched pairs of patients with NVAF, obesity, and diabetes were identified in the rivaroxaban and warfarin cohorts. Rate ratios of all-cause HRU were significantly reduced with rivaroxaban versus warfarin in all healthcare settings evaluated, except emergency room visits. The greatest impact was on physician office visits followed by hospital outpatient and inpatient visits. NVAF-related HRU was significantly lower for rivaroxaban versus warfarin in all care settings. Consistent with these findings, the length of hospital stay was significantly reduced by approximately 4 days among all patients for both all-cause and NVAF-related hospitalizations in the rivaroxaban cohort compared with the warfarin cohort. Rivaroxaban was associated with reductions in all-cause total healthcare costs by more than $5000 PPPY and NVAF-related medical costs by approximately $1100 PPPY.

CONCLUSION

In comparison with warfarin, rivaroxaban reduced HRU and costs, particularly hospital inpatient and outpatient visits and physician office visits, in patients with NVAF and comorbidities of obesity and diabetes.

Edoxaban and the Issue of Drug-Drug Interactions: From Pharmacology to Clinical Practice

Edoxaban, a direct factor Xa inhibitor, is the latest of the non-vitamin K antagonist oral anticoagulants (NOACs). Despite being marketed later than other NOACs, its use is now spreading in current clinical practice, being indicated for both thromboprophylaxis in patients with non-valvular atrial fibrillation (NVAF) and for the treatment and prevention of venous thromboembolism (VTE). In patients with multiple conditions, the contemporary administration of several drugs can cause relevant drug-drug interactions (DDIs), which can affect drugs' pharmacokinetics and pharmacodynamics. Usually, all the NOACs are considered to have significantly fewer DDIs than vitamin K antagonists; notwithstanding, this is actually not true, all of them are affected by DDIs with drugs that can influence the activity (induction or inhibition) of P-glycoprotein (P-gp) and cytochrome P450 3A4, both responsible for the disposition and metabolism of NOACs to a different extent. In this review/expert opinion, we focused on an extensive report of edoxaban DDIs. All the relevant drugs categories have been examined to report on significant DDIs, discussing the impact on edoxaban pharmacokinetics and pharmacodynamics, and the evidence for dose adjustment. Our analysis found that, despite a restrained number of interactions, some strong inhibitors/inducers of P-gp and drug-metabolising enzymes can affect edoxaban concentration, just as it happens with other NOACs, implying the need for a dose adjustment. However, our analysis of edoxaban DDIs suggests that given the small propensity for interactions of this agent, its use represents an acceptable clinical decision. Still, DDIs can be significant in certain clinical situations and a careful evaluation is always needed when prescribing NOACs.

Effects of obesity and diabesity on heart rhythm in the Zucker rat

Obesity and type 2 diabetes mellitus are risk factors for hypertension, coronary heart disease, cardiac arrhythmias including atrial fibrillation, heart failure and sudden cardiac death. The effects of obesity and diabesity on heart rhythm were investigated in the Zucker diabetic fatty (ZDF) and Zucker fatty (ZF) compared to the Zucker lean (ZL) control rat. In vivo biotelemetry techniques were used to assess the electrocardiogram and other cardiac and metabolic parameters. ZDF rats were characterized by age-dependent elevations in fasting and non-fasting blood glucose, glucose intolerance and weight gain and ZF rats were characterized by smaller elevations in fasting and non-fasting blood glucose and greater weight gain compared to ZL rats. Heart rate (HR) was progressively reduced in ZDF, ZF and ZL rats. At 195 days (6.5 months) of age there were significant differences in HR between ZDF (265 ± 8 bpm, n = 10), ZF (336 ± 9 bpm, n = 10) and ZL (336 ± 10 bpm, n = 10) rats and significant differences in HRV between ZDF (22 ± 1 bpm, n = 10), ZF (27 ± 1 bpm, n = 10) and ZL (31 ± 1 bpm, n = 10) rats. Power spectral analysis revealed no significant (P > 0.05) differences in HRV at low frequencies, reduced HRV at high frequencies and increased sympathovagal balance in ZDF compared to ZF and ZL rats. HR was reduced by ageing and additionally reduced by diabesity in the absence of changes in physical activity and body temperature. Reductions in HRV associated with altered sympathovagal drive might partly underlie disturbed HR in the ZDF rat. Possible explanations for reduced HR and future mechanistic studies are discussed.

The impact of weight loss related to risk of new-onset atrial fibrillation in patients with type 2 diabetes mellitus treated with sodium-glucose cotransporter 2 inhibitor

Background

Sodium–glucose cotransporter 2 inhibitor (SGLT2i) use reduces body weight (BW) in patients with type 2 diabetes mellitus (T2DM). Obesity and T2DM are strong risk factors of new-onset atrial fibrillation (AF). However, whether BW loss following SGLT2i treatment reduces AF risk in patients with T2DM remains unclear.

Methods

We used a medical database from a multicenter health care provider in Taiwan, which included 10,237 patients with T2DM, from June 1, 2016 to December 31, 2018, whose BW data at baseline and at 12 weeks of SGLT2i treatment were available. Patients were followed up from the drug index date until the occurrence of new-onset AF, discontinuation of the SGLT2i, or the end of the study period, whichever occurred first.

Results

The patients’ baseline body mass index (BMI) was 28.08 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pm$$\end{document}± 4.88 kg/m². SGLT2i treatment was associated with a BW loss of 1.35 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pm$$\end{document}± 3.28 kg (1.78%\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pm$$\end{document}± 4.47%). There were 37.4%, 47.0%, and 15.6% of patients experienced no-BW loss (n = 3832), BW loss 0.0–4.9% (n = 4814), and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge$$\end{document}≥ 5.0% (n = 1591) following SGLT2i treatment, respectively. Compared with patients with baseline BMI < 23 kg/m², AF risk significantly increased in patients with baseline BMI \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge$$\end{document}≥ 27.5 kg/m² (P for trend = 0.015). Compared with those without BW loss after SGLT2i treatment, AF risk significantly decreased with a BW loss of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge$$\end{document}≥ 5.0% (adjusted hazard ratios [95% confidence intervals]: 0.39[0.22–0.68]). Use of diuretics, old age, high-dose SGLT2i, higher estimated glomerular filtration rate, and baseline BMI were independent factors associated with a BW loss of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge$$\end{document}≥ 5.0% following SGLT2i initiation. By contrast, neither baseline BMI nor BW loss after SGLT2i treatment predicted major cardiovascular adverse events or heart failure hospitalization risk (P for trend > 0.05).

Conclusion

BW loss of ≥ 5.0% following SGLT2i treatment was associated with a lower risk of new-onset AF in patients with T2DM in real-world practice.

Race, Body Mass Index, and the Risk of Atrial Fibrillation: The Multi-Ethnic Study of Atherosclerosis

Background

Higher body mass index (BMI) is associated with increased risk of incident atrial fibrillation (AF), but it is not known whether this relationship varies by race/ethnicity.

Methods and Results

Eligible participants (6739) from MESA (Multi‐Ethnic Study of Atherosclerosis) were surveilled for incident AF using MESA hospital surveillance, scheduled MESA study ECG, and Medicare claims data. After a median 13.8 years of follow‐up, 970 participants (14.4%) had incident AF. With BMI modeled categorically in a Cox proportional hazards model, only those with grade II and grade III obesity had increased risks of AF (hazard ratio [HR], 1.50; 95% CI, 1.14–1.98, P=0.004 for grade II obesity and HR, 2.13; 95% CI, 1.48–3.05, P<0.0001 for grade III obesity). The relationship between BMI and AF risk was J‐shaped. However, the risk of AF as a function of BMI varied substantially by race/ethnicity (P value for interaction=0.02), with Chinese‐American participants having a much higher risk of AF with higher BMI and Black participants having minimal increased risk of AF with higher BMI.

Conclusions

Obesity is associated with an increased risk of incident AF, but the relationship between BMI and the risk of AF is J‐shaped and this relationship differs by race/ethnicity, such that Chinese‐American participants have a more pronounced increased risk of AF with higher BMI, while Black participants have minimal increased risk. Further exploration of the differential effects of BMI by race/ethnicity on cardiovascular outcomes is needed.

Weight, height, weight change, and risk of incident atrial fibrillation in middle-aged men and women

BACKGROUND

Anthropometric factors are reported to be risk factors for atrial fibrillation (AF), but it is unclear whether weight change in mid-life is associated with AF. We aimed to study the possible associations of weight, height, and weight change with the risk of incident AF in men and women.

METHODS

Our study cohort included 108 417 persons (51% women) who participated in a population-based health examination in northern Sweden at 30, 40, 50, or 60 years of age. The health examination included weight and height measurement and collection of data regarding cardiovascular risk factors. Within this cohort, 40 275 participants underwent two health examinations with a 10-year interval. We identified cases with a first-ever diagnosis of AF through the Swedish National Patient Registry.

RESULTS

During a total follow-up of 1 469 820 person-years, 5154 participants developed incident AF. The mean age at inclusion was 46.3 years, and mean age at AF diagnosis was 66.6 years. After adjustment for potential confounders, height, weight, body mass index (BMI), and body surface area (BSA) were positively associated with risk of incident AF in both men and women. Among participants who underwent two health examinations 10 years apart, 1142 persons developed AF. The mean weight change from baseline was a gain of 4.8%. Weight gain or weight loss was not significantly associated with risk of incident AF.

CONCLUSIONS

Height, weight, BMI, and BSA showed positive associations with risk of incident AF in both men and women. Midlife weight change was not significantly associated with AF risk.

Body Mass Index, Sex, and Incident Atrial Fibrillation in Diabetes: The ACCORD Trial

OBJECTIVES

This study sought to characterize the relationship between obesity and the risk of atrial fibrillation (AF) in diabetes.

BACKGROUND

Obesity is associated with increased risk of AF in the general population, but there is evidence that this relationship may differ in those with diabetes.

METHODS

Cox proportional hazards models were used to examine the association between body mass index (BMI) and incident AF on study electrocardiogram in participants from the ACCORD (Action to Control Cardiovascular Risk in Diabetes) trial.

RESULTS

Among 10,074 ACCORD participants (age 62.7 ± 6.6 years, 38.7% women, 62.2% white), 8.4% were normal weight, 29.0% were overweight, 53.1% were obese, and 9.5% were severely obese. Participants with obesity and severe obesity had increased risks of AF compared with normal weight (hazard ratio [HR]: 1.91; 95% confidence interval [CI]: 1.03 to 3.93; and HR: 3.69; 95% CI: 1.79 to 8.22, respectively). There was a 51% increased risk of AF per SD (5.4 U) BMI increase. However, there was a sex and BMI interaction-in men, obesity and severe obesity were associated with a substantially increased AF risk (HR: 3.19; 95% CI: 1.27 to 7.31; and HR: 4.79; 95% CI: 2.11 to 11.93, respectively), whereas there was no statistically significant association in women.

CONCLUSIONS

In those with diabetes, obesity and severe obesity are associated with increased risk of AF, but there is an interaction between sex and BMI, such that elevated BMI appears to confer a much greater risk of AF in men than in women. Further studies exploring the differential effects of BMI on AF risk in men and women are needed.

High variability in bodyweight is associated with an increased risk of atrial fibrillation in patients with type 2 diabetes mellitus: a nationwide cohort study

Background

Bodyweight variability is a risk factor for atrial fibrillation (AF). We aimed to examine the relationship between bodyweight variability and the risk of AF in patients with type 2 diabetes mellitus (DM), and whether this relationship was affected by baseline body mass index (BMI), weight change, or advanced diabetic stage.

Methods

A nationwide population-based cohort of 670,797 patients with type 2 DM from the Korean National Health Insurance Service database without a history of AF and with ≥ 3 measurements of bodyweight over a 5-year period were followed up for AF development. Intra-individual bodyweight variability was calculated using variability independent of mean, and high bodyweight variability was defined as the quintile with the highest variability with the lower four quintiles as reference.

Results

During a median of 7.0 years of follow-up, 22,019 patients (3.3%) newly developed AF. After multivariate adjustment, those in the highest quintile of bodyweight variability showed a higher risk of incident AF (HR 1.16, 95% CI 1.12–1.20) compared to those in the lower 4 quintiles with reference bodyweight variability, irrespective of baseline BMI group and direction of overall weight change. This association was greater in magnitude in subjects with lower BMI, those on insulin, and those with a DM duration of greater than 5 years. In sensitivity analyses, high bodyweight variability was consistently associated with AF development using other indices of variability and adjusting for glycemic variability.

Conclusions

High variability in bodyweight was associated with AF development, independently of traditional cardiovascular risk factors and baseline BMI. This association was stronger in underweight patients and with advanced diabetic stage. Weight fluctuation may interfere with the beneficial effects of weight loss and should be avoided when possible in weight control regimens for DM patients.

Glycemic control is associated with atrial structural remodeling in patients with type 2 diabetes

Background

Diabetes mellitus (DM) has been demonstrated to be a strong risk factor for development and perpetuation of atrial fibrillation (AF). However, how DM and glycemic control affect the pathogenesis of AF has not been sufficiently investigated, especially for the atrial structural remodeling.

Methods

A total of 86 patients undergoing coronary artery bypass graft surgery were enrolled in this study, with atrium sample collected in the operation. The patients were divided into the DM group (n = 40) and the control group (n = 46) accordingly. Demographics, clinical data were collected and compared. Echocardiography, Masson staining and Western blotting were conducted to evaluate atrial structural remodeling.

Results

There was no significant difference between the two groups in baseline characteristics (all P > 0.05). Fast blood glucose and HbA1c of DM group were significantly higher than the control group (P < 0.001). Echocardiography results demonstrated that the left atrium diameter (LAD) and left atrium volume index (LAVI) of DM group was significantly higher than the control group (P < 0.001). Masson staining showed that the collagen volume fraction (CVF), a quantitative indicator of fibrosis, was significantly higher in DM patients (P = 0.03). Western blot results indicated that the Collagen I of DM group was more expressed in the DM group than the control group (P < 0.001). Univariate linear regression revealed that the HbA1c level was significantly associated with both LAD (Y = 1.139X + 25.575, P < 0.001, R² = 0.291) and CVF (Y = 0.444X + 29.648, P = 0.009, R² = 0.078).

Conclusions

DM was associated with atrial structural remodeling, including atrium enlargement and atrial fibrosis, which might be attributed to poor glycemic control.

Gender Differences in Arrhythmias: Focused on Atrial Fibrillation

There are significant differences in clinical presentation and treatment of atrial fibrillation (AF) between women and men. The primary goal of AF management is to restore sinus rhythm and to prevent various complications, including stroke and heart failure. In many areas of AF, such as prevalence, clinical manifestations, morbidity, risk factors, pathophysiology, treatment strategies, and complications, gender-specific variability is observed and needs to be further addressed by large-scale population researches or randomized clinical trials, which help to promote the customization of AF treatment programs, hence to maximize the success rate of AF therapy in both sexes. This review highlights our current understanding of these gender differences in AF and how these differences affect treatment decisions on 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.

Weight change and the risk of incident atrial fibrillation: a systematic review and meta-analysis

BACKGROUND

The prevalence of obesity is increasing globally and this could partly explain the worldwide increase in the prevalence of atrial fibrillation (AF), as both overweight and obesity are established risk factors. However, the relationship between weight change and risk of incident AF, independent of starting weight, remains uncertain.

METHODS

MEDLINE, Embase, Pubmed, Web of Science, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, Trials Register-clinicaltrials.gov, CINAHL and the WHO ICTRP were searched from inception to July 2018.We included randomised controlled trials and cohort studies across all healthcare settings but excluded studies of bariatric surgery. A random effects model was used to calculate pooled hazard ratios. The primary outcome was the risk of incident AF in relation to weight change.

RESULTS

Ten studies, including 108 996 people, met our inclusion criteria. For a 5% gain in weight, the incidence of AF increased by 13% (HR 1.13, 95% CI 1.04 to 1.23, I²=70%, n>20 411 in five studies; study size was unknown for one study). A 5% loss in body weight was not associated with a significant change in the incidence of AF (HR 1.04, 95% CI 0.94 to 1.16, I²=73%, n=40 704 in five studies).

CONCLUSIONS

Weight gain may increase the risk of AF, but there was no clear evidence that non-surgical weight loss altered AF incidence. Strategies to prevent weight gain in the population may reduce the global burden of AF. Given the lack of studies and methodological limitations, further research is needed.

Effect of catheter ablation on pre-existing abnormalities of left atrial systolic, diastolic, and neurohormonal functions in patients with chronic heart failure and atrial fibrillation

The critical role of the left atrium (LA) in cardiovascular homoeostasis is mediated by its reservoir, conduit, systolic, and neurohormonal functions. Atrial fibrillation is generally a reflection of underlying disease of the LA, especially in patients with heart failure. Disease-related LA remodelling leads to a decline in both atrial contractility and distensibility along with an impairment in the control of neurohormonal systems that regulate intravascular volume. Catheter ablation can lead to further injury to the atrial myocardium, as evidenced by post-procedural troponin release and tissue oedema. The cardiomyocyte loss leads to replacement fibrosis, which may affect up to 30-35% of the LA wall. These alterations further impair atrial force generation and neurohormonal functions; the additional loss of atrial distensibility can lead to a 'stiff LA syndrome', and the fibrotic response predisposes to recurrence of the atrial arrhythmia. Although it intends to restore LA systole, catheter ablation often decreases the chamber's transport functions. This is particularly likely in patients with long-standing atrial fibrillation and pre-existing LA fibrosis, especially those with increased epicardial adipose tissue (e.g. patients with obesity, diabetes and/or heart failure with a preserved ejection fraction). Although the fibrotic LA in these individuals is an ideal substrate for the development of atrial fibrillation, it may be a suboptimal substrate for catheter ablation. Such patients are not likely to experience long-term restoration of sinus rhythm, and catheter ablation has the potential to worsen their haemodynamic and clinical status. Further studies in this vulnerable group of patients are needed.

Diabetes and Arrhythmias: Pathophysiology, Mechanisms and Therapeutic Outcomes

The prevalence of diabetes is rapidly increasing and closely associated with cardiovascular morbidity and mortality. While the major cardiovascular complication associated with diabetes is coronary artery disease, it is becoming increasingly apparent that diabetes impacts the electrical conduction system in the heart, resulting in atrial fibrillation, and ventricular arrhythmias. The relationship between diabetes and arrhythmias is complex and multifactorial including autonomic dysfunction, atrial and ventricular remodeling and molecular alterations. This review will provide a comprehensive overview of the link between diabetes and arrhythmias with insight into the common molecular mechanisms, structural alterations and therapeutic outcomes.

Arrhythmogenic Substrates for Atrial Fibrillation in Obesity

Global obesity rates have nearly tripled since 1975. This obesity rate increase is mirrored by increases in atrial fibrillation (AF) that now impacts nearly 10% of Americans over the age of 65. Numerous epidemiologic studies have linked incidence of AF and obesity and other obesity-related diseases, including hypertension and diabetes. Due to the wealth of epidemiologic data linking AF with obesity-related disease, mechanisms of AF pathogenesis in the context of obesity are an area of ongoing investigation. However, progress has been somewhat slowed by the complex phenotype of obesity; separating the effects of obesity from those of related sequelae is problematic. While the initiation of pathogenic pathways leading to AF varies with disease (including increased glycosylation in diabetes, increased renin angiotensin aldosterone system activation in hypertension, atrial ischemia in coronary artery disease, and sleep apnea) the pathogenesis of AF is united by shared mediators of altered conduction in the atria. We suggest focusing on these downstream mediators of AF in obesity is likely to yield more broadly applicable data. In the context of obesity, AF is driven by the interrelated processes of inflammation, atrial remodeling, and oxidative stress. Obesity is characterized by a constant low-grade inflammation that leads to increased expression of pro-inflammatory cytokines. These cytokines contribute to changes in cardiomyocyte excitability. Atrial structural remodeling, including fibrosis, enlargement, and fatty infiltration is a prominent feature of AF and contributes to the altered conduction. Finally, obesity impacts oxidative stress. Within the cardiomyocyte, oxidative stress is increased through both increased production of reactive oxygen species and by downregulation of scavenging enzymes. This increased oxidative stress modulates of cardiomyocyte excitability, increasing susceptibility to AF. Although the initiating insults vary, inflammation, atrial remodeling, and oxidative stress are conserved mechanisms in the pathophysiology of AF in the obese patients. In this review, we highlight mechanisms that have been shown to be relevant in the pathogenesis of AF across obesity-related disease.

Body size and risk of atrial fibrillation: a cohort study of 1.1 million young men

BACKGROUND

Whilst tall stature has been related to lower risk of vascular disease, it has been proposed as a risk factor for atrial fibrillation. Little is known about other anthropometric measures and their joint effects on risk of atrial fibrillation.

OBJECTIVES

We aim to investigate associations and potential joint effects of height, weight, body surface area (BSA) and body mass index (BMI) with risk of atrial fibrillation.

METHODS

In a cohort covering 1 153 151 18-year-old men participating in the Swedish military conscription (1972-1995), Cox regression was used to investigate associations of height, weight, BSA and BMI with risk of atrial fibrillation.

RESULTS

During a median of 26.3 years of follow-up, higher height was associated with higher risk of atrial fibrillation (hazard ratio [HR] 2.80; 95% CI 2.63-2.98; for 5th vs. 1st quintile) and so was larger BSA (HR 3.05; 95% CI 2.82-3.28; for 5th vs. 1st quintile). Higher weight and BMI were to a lesser extent associated with risk of atrial fibrillation (BMI: 1.42; 95% CI 1.33-1.52, for 5th vs. 1st quintile). We found a multiplicative joint effect of height and weight. Adjusting for muscle strength, exercise capacity and diseases related to atrial fibrillation attenuated these measures.

CONCLUSIONS

Higher height and weight are strongly associated with higher risk of atrial fibrillation. These associations are multiplicative and independent of each other and are summarized in a strong association of body surface area with risk of atrial fibrillation. The mechanisms remain unknown but may involve increased atrial volume load with larger body size.

Obesity is associated with incident atrial fibrillation independent of gender: A meta-analysis

BACKGROUND

The prevalence of obesity is increasing among the general population. Obesity is associated with increased risk of several cardiovascular conditions, which in turn may increase the risk for atrial fibrillation (AF). We performed a meta-analysis of cohort studies that examined the effect of obesity on the incidence of AF. In addition, we examined the effect of obesity on the incidence of AF stratified by gender.

METHODS AND RESULTS

We searched the MEDLINE and EMBASE databases for studies evaluating the effect of obesity on AF. Pooled risk ratios (RR) with 95% confidence intervals (CI) were calculated using a random effects model. Sixteen trials involving 587,372 subjects were included in the analysis. Obesity was defined as body mass index >30 kg/m² . AF during follow-up developed in 5,751 of 91,031 (6.3%) obese subjects and in 15,346 of 496,341 (3.1%) nonobese subjects (RR = 1.51, 95% CI 1.35 to 1.68; P < 0.00001). Based on the pooled estimate across the studies, the effect of obesity on incident AF was similar in men (RR = 1.41, 95% 1.24 to 1.62; P < 0.00001) and women (RR = 1.53, 95% CI 1.19 to 1.97; P < 0.00001).

CONCLUSION

Obesity is associated with an increased risk of new-onset AF in susceptible individuals. This effect appears to be consistent in both genders. Further studies are warranted to examine the impact of weight loss interventions on the risk of developing AF.

Dipeptidyl peptidase-4 inhibitor decreases the risk of atrial fibrillation in patients with type 2 diabetes: a nationwide cohort study in Taiwan

BACKGROUND

Whether dipeptidyl peptidase-4 inhibitor (DPP4i) is associated with a lower risk of new-onset atrial fibrillation (AF) in patients with diabetes remains unclear. This study aimed to evaluate the risk of AF associated with use of DPP4i among a longitudinal cohort of patients with diabetes.

METHODS

Over a 3-year period, 480,000 patients with diabetes were analyzed utilizing Taiwan's National Health Insurance Research Database and 90,880 patients taking metformin as first-line therapy were enrolled. Patients were further divided into two groups: (1) DPP4i users: those taking DPP4i and (2) non-DPP4i users: those prescribed other hypoglycemic agents (HAs) as second-line drug. Study end point was defined by diagnosis of AF, addition of any third-line HA, or the end of the study period (December 31, 2013), whichever came first.

RESULTS

A total of 16,017 DPP4i users and 74,863 non-DPP4i users were eligible for the study. For the DPP4i group, most patients were prescribed sitagliptin (n = 12,180; 76%). Among the non-DPP4i group, most patients took sulfonylurea (n = 60,606; 81%) as their second-line medication. DPP4i users were associated with a lower risk of new-onset AF compared with non-DPP4i users after propensity-score weighting (hazard ratio 0.65; P < 0.0001). Subgroup analysis showed that DPP4i user were associated with a lower risk of new-onset AF compared with non-DPP4i users in most subgroups. Multivariate analysis indicated that use of DPP4i was associated with lower risk of new-onset AF and age > 65 years, presence of hypertension, and ischemic heart disease were independent risk factors for new-onset AF.

CONCLUSIONS

Among patients with diabetes prescribed with metformin, the patients with DPP4i as second HA were associated with a lower risk of AF compared with the patients with other drugs as second HAs in real-world practice.

Early Reverse Cardiac Remodeling Effect of Laparoscopic Sleeve Gastrectomy

BACKGROUND

This study evaluated the early postoperative benefits of laparoscopic sleeve gastrectomy (LSG) on the left ventricular (LV) function and left atrial (LA) structural, mechanical, and electrical functions in severely obese patients.

METHODS

Thirty-two patients with severe obesity who were consecutively scheduled for LSG and 30 healthy controls were included in the study. LV global longitudinal strain (LGS), peak atrial longitudinal strain (PALS), and strain rates (S-Sr, E-Sr, and A-Sr) of the lateral and septal LA walls, and intra- and interatrial dyssynchrony periods for all subjects were evaluated using strain echocardiography. The measurements were repeated in patients 1 month after surgery.

RESULTS

LGS of the LV was significantly depressed in the patient group compared with the control group (p < 0.001). LA peak septal and lateral wall strain values were significantly lower in patients than in controls (both p values <0.001). LA intra- and interatrial dyssynchrony periods were longer in patients than in controls (p = 0.012 and p = 0.004, respectively). LGS significantly improved after LSG (p < 0.001). Significant reductions were noted in the LA antero-posterior diameter (p < 0.001), LA volume index (LAVI, p = 0.001), and in the mitral velocity to the early diastolic velocity of the mitral annulus ratio (E/e' ratio, p = 0.046). The PALS of the septal and lateral LA walls significantly increased (p = 0.001 and p < 0.001, respectively). S-Sr, E-Sr, and A-Sr values of the septal LA wall (p = 0.049, p < 0.001, and p = 0.001, respectively) and the lateral LA wall (p = 0.009, p = 0.007, and p = 0.002, respectively) significantly improved postoperatively. Intra- and interatrial dyssynchrony significantly decreased (p = 0.001 and p < 0.001, respectively). Weight loss positively correlated with changes in LGS (R = 0.39, p = 0.039), LAVI (R = 0.39, p = 0.034), intra-atrial dyssynchrony (R = 0.45, p = 0.021), interatrial dyssynchrony (R = 0.42, p = 0.038), septal LA wall peak strain (R = 0.44, p = 0.027), lateral LA wall peak strain (R = 0.46, p = 0.017), septal LA wall A-Sr (R = 0.43, p = 0.028), and lateral LA wall A-Sr (R = 0.46, p = 0.019). The comparison of postoperative findings of the patients with controls revealed that the LA diameter, both LA volume and volume index (LAVI), E/e' ratio, S-Sr and E-Sr of both lateral and septal LA walls, intra- and interatrial LA dyssynchrony of the patient group became similar to the control group (all p value >0.05). Postoperative A-Sr values of both LA walls (both p value <0.001) were higher in patients than controls.

CONCLUSION

The benefits of LSG on LV and LA function may be observed even in the early postoperative phase. The resulting weight loss correlates with LV and LA reverse remodeling in severely obese patients.

Oxidative stress and inflammation as central mediators of atrial fibrillation in obesity and diabetes

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in humans. Several risk factors promote AF, among which diabetes mellitus has emerged as one of the most important. The growing recognition that obesity, diabetes and AF are closely intertwined disorders has spurred major interest in uncovering their mechanistic links. In this article we provide an update on the growing evidence linking oxidative stress and inflammation to adverse atrial structural and electrical remodeling that leads to the onset and maintenance of AF in the diabetic heart. We then discuss several therapeutic strategies to improve atrial excitability by targeting pathways that control oxidative stress and inflammation.

Increased healthcare utilization costs following initiation of insulin treatment in type 2 diabetes: A long-term follow-up in clinical practice

AIMS

To compare long-term changes in healthcare utilization and costs for type 2 diabetes patients before and after insulin initiation, as well as healthcare costs after insulin versus non-insulin anti-diabetic (NIAD) initiation.

METHODS

Patients newly initiated on insulin (n=2823) were identified in primary health care records from 84 Swedish primary care centers, between 1999 to 2009. First, healthcare costs per patient were evaluated for primary care, hospitalizations and secondary outpatient care, before and up to seven years after insulin initiation. Second, patients prescribed insulin in second line were matched to patients prescribed NIAD in second line, and the healthcare costs of the matched groups were compared.

RESULTS

The total mean annual healthcare cost increased from €1656 per patient 2 years before insulin initiation to €3814 seven years after insulin initiation. The total cumulative mean healthcare cost per patient at year 5 after second-line treatment was €13,823 in the insulin group compared to €9989 in the NIAD group.

CONCLUSIONS

Initiation of insulin in type 2 diabetes patients was followed by increased healthcare costs. The increases in costs were larger than those seen in a matched patient population initiated on NIAD treatment in second-line.

Genetic Obesity and the Risk of Atrial Fibrillation: Causal Estimates from Mendelian Randomization

BACKGROUND

Observational studies have identified an association between body mass index (BMI) and incident atrial fibrillation (AF). Inferring causality from observational studies, however, is subject to residual confounding, reverse causation, and bias. The primary objective of this study was to evaluate the causal association between BMI and AF by using genetic predictors of BMI.

METHODS

We identified 51 646 individuals of European ancestry without AF at baseline from 7 prospective population-based cohorts initiated between 1987 and 2002 in the United States, Iceland, and the Netherlands with incident AF ascertained between 1987 and 2012. Cohort-specific mean follow-up ranged from 7.4 to 19.2 years, over which period there was a total of 4178 cases of incident AF. We performed a Mendelian randomization with instrumental variable analysis to estimate a cohort-specific causal hazard ratio for the association between BMI and AF. Two genetic instruments for BMI were used: FTO genotype (rs1558902) and a BMI gene score comprising 39 single-nucleotide polymorphisms identified by genome-wide association studies to be associated with BMI. Cohort-specific estimates were combined by random-effects, inverse variance-weighted meta-analysis.

RESULTS

In age- and sex-adjusted meta-analysis, both genetic instruments were significantly associated with BMI (FTO: 0.43 [95% confidence interval, 0.32-0.54] kg/m2 per A-allele, P<0.001; BMI gene score: 1.05 [95% confidence interval, 0.90-1.20] kg/m2 per 1-U increase, P<0.001) and incident AF (FTO, hazard ratio, 1.07 [1.02-1.11] per A-allele, P=0.004; BMI gene score, hazard ratio, 1.11 [1.05-1.18] per 1-U increase, P<0.001). Age- and sex-adjusted instrumental variable estimates for the causal association between BMI and incident AF were hazard ratio, 1.15 (1.04-1.26) per kg/m2, P=0.005 (FTO) and 1.11 (1.05-1.17) per kg/m2, P<0.001 (BMI gene score). Both of these estimates were consistent with the meta-analyzed estimate between observed BMI and AF (age- and sex-adjusted hazard ratio 1.05 [1.04-1.06] per kg/m2, P<0.001). Multivariable adjustment did not significantly change findings.

CONCLUSIONS

Our data are consistent with a causal relationship between BMI and incident AF. These data support the possibility that public health initiatives targeting primordial prevention of obesity may reduce the incidence of AF.

Second line initiation of insulin compared with DPP-4 inhibitors after metformin monotherapy is associated with increased risk of all-cause mortality, cardiovascular events, and severe hypoglycemia

AIMS

The objective of this nationwide study was to compare the risk of all-cause mortality, fatal and nonfatal cardiovascular disease (CVD), and severe hypoglycemia in patients with type 2 diabetes (T2D) on metformin monotherapy treatment starting second-line treatment with either insulin or dipeptidyl peptidase-4 inhibitor (DPP-4i).

METHODS

All patients with T2D in Sweden who initiated second-line treatment with insulin or DPP-4i after metformin monotherapy during 2007-2014 identified in the Swedish Prescribed Drug Register were followed for outcome in the Cause of Death and National Patient Registers. Insulin and DPP-4i patients were matched 1:1 using propensity-score matching. Comparisons between groups were performed using unadjusted Cox regression models. Additionally, multivariate adjusted survival models were used to test the results using the full population without matching.

RESULTS

Of 27,767 mono-metformin-treated patients, 55.7% started insulin and 44.3% a DPP-4i, and after matching both groups had 9278 patients each. Median follow-up (patients years) times were 3.84 (37,578) and 3.93 (37,983) for insulin and DPP-4i-groups, respectively. Insulin compared with DPP-4i was associated with higher risk of subsequent all-cause mortality, fatal and nonfatal CVD, and severe hypoglycemia; adjusted HR (95% CI): 1.69 (1.45-1.96); 1.39 (1.21-1.61); and 4.35 (2.26-8.35), respectively. When performing multivariate adjusted analyses on the full population similar results were found.

CONCLUSIONS

Initiation of insulin, compared with DPP-4i treatment, was associated with an increased risk of subsequent all-cause mortality, fatal and nonfatal CVD, and severe hypoglycemia. Results from randomized trials will be important to elucidate causal relationships.

Characteristics and outcomes of diabetic patients with an implantable cardioverter defibrillator in a real world setting: results from the Israeli ICD registry

Aims

There are limited data regarding the effect of diabetes mellitus (DM) on the risks of both appropriate and inappropriate implantable cardioverter defibrillator (ICD) therapy. The present study was designed to compare the outcome of appropriate and inappropriate ICD therapy in patients with or without DM.

Methods and results

The risk of a first appropriate ICD therapy for ventricular tachyarrhythmias (including anti tachycardia pacing and shock) was compared between 764 DM and 1346 non-DM patients enrolled in the national Israeli ICD registry. We also compared the risks of inappropriate ICD therapy, and death or cardiac hospitalization between diabetic and non-diabetic patients. Diabetic patients were older, were more likely to have ischemic cardiomyopathy, lower ejection fraction, atrial fibrillation, and other co-morbidities. The 3-year cumulative incidence of appropriate ICD therapy was similar in the DM and non-DM groups (12 and 13%, respectively, p = 0.983). Multivariate analysis showed that DM did not affect the risk of appropriate ICD therapy (HR = 1.07, 95% CI 0.78–1.47, p = 0.694) or inappropriate therapy (HR = 0.72, 95% CI 0.42–1.23, p = 0.232). However, DM was associated with a 31% increased risk for death or cardiac hospitalization (p = 0.005). Results were similar in subgroup analyses including ICD and defibrillators with cardiac resynchronization therapy function recipients, primary or secondary prevention indication for an ICD.

Conclusions

Despite a significant excess of cardiac hospitalizations and mortality in the diabetic population, there was no difference in the rate of ICD treatments, suggesting that the outcome difference is not related to arrhythmias.

Clinical significance of nutritional status in patients with atrial fibrillation: An overview of current evidence

BACKGROUND

Obesity is a well-known atherosclerosis risk factor; however, its role and the importance of undernutrition in atrial fibrillation (AF) pathogenesis are still not well understood. The aim of this study was to present the current state of knowledge on this issue in different groups of patients.

METHODS

Systematic review of papers published between 1980 and 2016.

RESULTS

The literature shows contradicting views regarding the impact of nutritional status on the risk, course, and complications of AF. On the one hand, it has been revealed that overweight, obesity, and high birth mass increase the risk of AF, and that their reduction is linked to an improved course of AF and reduced all-cause and cardiovascular mortality. On the other hand, a so-called obesity paradox has been found, which shows lower all-cause mortality in overweight patients with AF compared to those of normal weight or who are underweight. It has also been shown, although based on a small number of studies, that the relationship between nutritional status and risk of AF and its complication may be U-shaped, which means that not only patients with obesity, but also individuals with underweight, cachexia, and low birth weight may have an increased risk and poor outcome of AF.

CONCLUSIONS

The relationship between patients' nutritional status and the course of AF has become clearer but it requires further studies examining the importance of weight reduction on AF course.

Impact of Body Mass Index on the Prognosis of Japanese Patients With Non-Valvular Atrial Fibrillation

Obesity is a risk factor for atrial fibrillation (AF); however, obesity is associated with lower mortality in patients with established AF, a phenomenon known as the obesity paradox. Previous studies reported inconsistent results regarding effects of body weight on risk of cardiogenic embolism in patients with AF. To determine relation between body mass index (BMI) and prognosis among Japanese patients with nonvalvular AF (NVAF), a post hoc analysis was conducted using observational data in the J-RHYTHM Registry. Subjects were categorized as underweight (BMI <18.5), normal (18.5 to 24.9), overweight (25.0 to 29.9), or obese (≥30 kg/m(2)). End points included thromboembolism, major hemorrhaging, all-cause mortality, and cardiovascular mortality. Of the 7,406 patients with NVAF, 6,379 patients (70 ± 10 years old; BMI, 23.6 ± 3.9 kg/m(2)) having baseline BMI data constituted the study group. During the 2-year follow-up period, 111 patients had thromboembolism, 124 experienced major hemorrhage, and 159 died. Multivariate analysis with the Cox proportional hazards model showed that none of the BMI categories were independent predictors of thromboembolism. However, being underweight was an independent predictor of all-cause mortality (hazard ratio [HR] 2.45; 95% confidence interval [CI] 1.62 to 3.69; p <0.001) and cardiovascular mortality (HR 3.00, 95% CI 1.52 to 5.91, p = 0.001) when normal weight was used as the reference. Additionally, being overweight was a predictor of lower all-cause mortality (HR 0.60, 95% CI 0.37 to 0.95, p = 0.029). In conclusion, being underweight is associated with higher risks of all-cause and cardiovascular mortality compared with having a normal weight. Being overweight or obese is not associated with increased mortality among Japanese patients with NVAF.

Sulphonylurea compared to DPP-4 inhibitors in combination with metformin carries increased risk of severe hypoglycemia, cardiovascular events, and all-cause mortality

AIMS

There are safety concerns related to sulphonylurea treatment. The objective of this nationwide study was to compare the risk of cardiovascular disease (CVD), all-cause mortality and severe hypoglycemia in patients with type 2 diabetes (T2D) starting second-line treatment with either metformin+sulphonylurea or metformin+dipeptidyl peptidase-4 inhibitor (DPP-4i).

METHODS

All patients with T2D in Sweden who initiated second-line treatment with metformin+sulphonylurea or metformin+DPP-4i during 2006-2013 (n=40,736 and 12,024, respectively) were identified in this nationwide study. The Swedish Prescribed Drug Register and the Cause of Death and National Patient Registers were used, and Cox survival models adjusted for age, sex, fragility, prior CVD, and CVD-preventing drugs were applied to estimate risks of events. Propensity score adjustments and matching methods were used to test the results.

RESULTS

Of 52,760 patients; 77% started metformin+SU and 23% metformin+DPP-4i. Crude incidences for severe hypoglycemia, CVD, and all-cause mortality in the SU cohort were 2.0, 19.6, and 24.6 per 1000 patient-years and in the DPP-4i cohort were 0.8, 7.6, and 14.9 per 1000 patient-years, respectively. Sulphonylurea compared with DPP4i was associated with higher risk of subsequent severe hypoglycemia, fatal and nonfatal CVD, and all-cause mortality; adjusted HR (95% CI): 2.07 (1.11-3.86); 1.17 (1.01-1.37); and 1.25 (1.02-1.54), respectively. Results were confirmed by additional propensity-adjusted and matched analyses. Among the SU drugs, glibenclamide had the highest risks.

CONCLUSIONS

Metformin+SU treatment was associated with an increased risk of subsequent severe hypoglycemia, cardiovascular events, and all-cause mortality compared with metformin+DPP4i. Results from randomized trials will be important to elucidate causal relationships.

Achievement of treatment goals for secondary prevention of myocardial infarction or stroke in 29,325 patients with type 2 diabetes: a German/Austrian DPV-multicenter analysis

BACKGROUND

To analyze whether medical care is in accordance with guidelines for secondary prevention of myocardial infarction (MI), or stroke in patients with type 2 diabetes from Germany and Austria.

METHODS

29,325 patients (≥ 20 years of age) with type 2 diabetes and MI, or stroke, documented between 2006 and 2015 were selected from the Diabetes-Patienten-Verlaufsdokumentation database. We analyzed medication, clinical characteristics, and lifestyle factors according to national secondary prevention guidelines in patients with MI, or stroke, separately.

RESULTS

HbA1C <7.5 % was achieved in 64.9 % (MI), and in 61.1 % (stroke) of patients. LDL <100 mg/dl was documented in 56.2 % (MI), and in 42.2 % (stroke). Non-smoking was reported in 92.0 % (MI), and in 93.1 % (stroke), physical activity in 9.6 % (MI), and 5.5 % (stroke). Target values of blood pressure (<130/80 mmHg in MI, 120/70-140/90 in stroke) were reached in 67.0 % (MI), and in 89.9 % (stroke). Prescription prevalence of inhibitors of platelet aggregation (IPA) was 50.7 % (MI), and 31.7 % (stroke). 57.0 % (MI), and 40.1 % (stroke) used statins, 65.1 % (MI), and 65.8 % (stroke) used any type of antihypertensives, and ACE inhibitors were prescribed in 49.7 % (MI), and 41.3 % (stroke). A body mass index (BMI) <27 kg/m(2) and the use of beta blockers were only recommended in subjects with MI. Of the patients with MI, 32.0 % had a BMI <27 kg/m(2), and 59.5 % used beta blockers.

CONCLUSIONS

Achievement of treatment goals in secondary prevention of MI, or stroke in subjects with type 2 diabetes needs improvement. Target goals were met more frequently in patients with MI compared to subjects with stroke. Especially the use of IPA was very low in patients with stroke. There remains great potential to reduce the risk of repeated macrovascular events and premature death, as well as to increase patients' quality of life.

Long-term mortality and incidence of cardiovascular diseases and type 2 diabetes in diabetic and nondiabetic obese patients undergoing gastric banding: a controlled study

BACKGROUND AND AIM

Aim of this retrospective study was to compare long-term mortality and incidence of new diseases [diabetes and cardiovascular (CV) disease] in morbidly obese diabetic and nondiabetic patients, undergoing gastric banding (LAGB) in comparison to medical treatment.

PATIENTS AND METHODS

Medical records of obese patients [body mass index (BMI) > 35 kg/m(2) undergoing LAGB (n = 385; 52 with diabetes) or medical treatment (controls, n = 681; 127 with diabetes), during the period 1995-2001 (visit 1)] were collected. Patients were matched for age, sex, BMI, and blood pressure. Identification codes of patients were entered in the Italian National Health System Lumbardy database, that contains life status, causes of death, as well as exemptions, drug prescriptions, and hospital admissions (proxies of diseases) from visit 1 to September 2012. Survival was compared across LAGB patients and matched controls using Kaplan-Meier plots adjusted Cox regression analyses.

RESULTS

Observation period was 13.9 ± 1.87 (mean ± SD). Mortality rate was 2.6, 6.6, and 10.1 % in controls at 5, 10, and 15 years, respectively; mortality rate was 0.8, 2.5, and 3.1 % in LAGB patients at 5, 10, and 15 years, respectively. Compared to controls, surgery was associated with reduced mortality [HR 0.35, 95 % CI 0.19-0.65, p < 0.001 at univariate analysis, HR 0.41, 95 % CI 0.21-0.76, p < 0.005 at adjusted analysis], similar in diabetic [HR 0.34, 95 % CI 0.13-0.87, p = 0.025] and nondiabetic [HR 0.42, 95 % CI 0.19-0.97, p = 0.041] patients. Surgery was also associated with lower incidence of diabetes (15 vs 48 cases, p = 0.035) and CV diseases (52 vs 124 cases, p = 0.048), and of hospital admissions (88 vs 197, p = 0.04).

CONCLUSION

Up to 17 years, gastric banding is associated with reduced mortality in diabetic and nondiabetic patients, and with reduced incidence of diabetes and cardiovascular diseases.

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.

Cardiac Fibrosis in Patients With Atrial Fibrillation: Mechanisms and Clinical Implications

Atrial fibrillation (AF) is associated with structural, electrical, and contractile remodeling of the atria. Development and progression of atrial fibrosis is the hallmark of structural remodeling in AF and is considered the substrate for AF perpetuation. In contrast, experimental and clinical data on the effect of ventricular fibrotic processes in the pathogenesis of AF and its complications are controversial. Ventricular fibrosis seems to contribute to abnormalities in cardiac relaxation and contractility and to the development of heart failure, a common finding in AF. Given that AF and heart failure frequently coexist and that both conditions affect patient prognosis, a better understanding of the mutual effect of fibrosis in AF and heart failure is of particular interest. In this review paper, we provide an overview of the general mechanisms of cardiac fibrosis in AF, differences between fibrotic processes in atria and ventricles, and the clinical and prognostic significance of cardiac fibrosis in AF.