Sex, age, type of diabetes and incidence of atrial fibrillation in patients with diabetes mellitus: a nationwide analysis

SGLT2 inhibitors: from glucose-lowering to cardiovascular benefits

An increasing number of individuals are at high risk of type 2 diabetes (T2D) and its cardiovascular complications, including heart failure (HF), chronic kidney disease (CKD), and eventually premature death. The sodium-glucose co-transporter-2 (SGLT2) protein sits in the proximal tubule of human nephrons to regulate glucose reabsorption and its inhibition by gliflozins represents the cornerstone of contemporary T2D and HF management. Herein, we aim to provide an updated overview of the pleiotropy of gliflozins, provide mechanistic insights and delineate related cardiovascular (CV) benefits. By discussing contemporary evidence obtained in preclinical models and landmark randomized controlled trials, we move from bench to bedside across the broad spectrum of cardio- and cerebrovascular diseases. With landmark randomized controlled trials confirming a reduction in major adverse CV events (MACE; composite endpoint of CV death, non-fatal myocardial infarction, and non-fatal stroke), SGLT2 inhibitors strongly mitigate the risk for heart failure hospitalization in diabetics and non-diabetics alike while conferring renoprotection in specific patient populations. Along four major pathophysiological axes (i.e. at systemic, vascular, cardiac, and renal levels), we provide insights into the key mechanisms that may underlie their beneficial effects, including gliflozins' role in the modulation of inflammation, oxidative stress, cellular energy metabolism, and housekeeping mechanisms. We also discuss how this drug class controls hyperglycaemia, ketogenesis, natriuresis, and hyperuricaemia, collectively contributing to their pleiotropic effects. Finally, evolving data in the setting of cerebrovascular diseases and arrhythmias are presented and potential implications for future research and clinical practice are comprehensively reviewed.

Age and aging process alter the gut microbes

BACKGROUND

Gut microbes and age are both factors that influence the development of disease. The community structure of gut microbes is affected by age.

OBJECTIVE

To plot time-dependent gut microbe profiles in individuals over 45 years old and explore the correlation between age and gut microbes.

METHODS

Fecal samples were collected from 510 healthy individuals over 45 years old. Shannon index, Simpson index, Ace index, etc. were used to analyze the diversity of gut microbes. The beta diversity analysis, including non-metric multidimensional scaling (NMDS), was used to analyze community distribution. Linear discriminant analysis (LDA) and random forest (RF) algorithm were used to analyze the differences of gut microbes. Trend analysis was used to plot the abundances of characteristic gut microbes in different ages.

RESULTS

The individuals aged 45-49 had the highest richness of gut bacteria. Fifteen characteristic gut microbes, including Siphoviridae and Bifidobacterium breve, were screened by RF algorithm. The abundance of Ligiactobacillus and Microviridae were higher in individuals older than 65 years. Moreover, the abundance of Blautia_A massiliensis, Lubbockvirus and Enterocloster clostridioformis decreased with age and the abundance of Klebsiella variicola and Prevotella increased with age. The functional genes, such as human diseases and aging, were significantly different among different aged individuals.

CONCLUSIONS

The individuals in different ages have characteristic gut microbes. The changes in community structure of gut microbes may be related to age-induced diseases.

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.

Oral anticoagulation across diabetic subtypes in patients with newly diagnosed atrial fibrillation: A report from the GARFIELD-AF registry

AIMS

This study aims to describe both management and prognosis of patients with diabetes mellitus (DM) and newly diagnosed atrial fibrillation (AF), overall as well as by antidiabetic treatment, and to assess the influence of oral anticoagulation (OAC) on outcomes by DM status.

METHODS

The study population comprised 52 010 newly diagnosed patients with AF, 11 542 DM and 40 468 non-DM, enrolled in the GARFIELD-AF registry. Follow-up was truncated at 2 years after enrolment. Comparative effectiveness of OAC versus no OAC was assessed by DM status using a propensity score overlap weighting scheme and weights were applied to Cox models.

RESULTS

Patients with DM [39.3% oral antidiabetic drug (OAD), 13.4% insulin ± OAD, 47.2% on no antidiabetic drug] had higher risk profile, OAC use, and rates of clinical outcomes compared with patients without DM. OAC use was associated in patients without DM and patients with DM with lower risk of all-cause mortality [hazard ratio 0.75 (0.69-0.83), 0.74 (0.64-0.86), respectively] and stroke/systemic embolism (SE) [0.69 (0.58-0.83), 0.70 (0.53-0.93), respectively]. The risk of major bleeding with OAC was similarly increased in patients without DM and those with DM [1.40 (1.14-1.71), 1.37 (0.99-1.89), respectively]. Patients with insulin-requiring DM had a higher risk of all-cause mortality and stroke/SE [1.91 (1.63-2.24)], [1.57 (1.06-2.35), respectively] compared with patients without DM, and experienced significant risk reductions of all-cause mortality and stroke/SE with OAC [0.73 (0.53-0.99); 0.50 (0.26-0.97), respectively].

CONCLUSIONS

In both patients with DM and patients without DM with AF, OAC was associated with lower risk of all-cause mortality and stroke/SE. Patients with insulin-requiring DM derived significant benefit from OAC.

Risk of atrial fibrillation in individuals with dysglycemia and diabetes

OBJECTIVE

Diabetes is a risk factor for atrial fibrillation (AF), and increases the risk of thromboembolic events in persons with AF. However, the link between the two conditions is not fully elucidated. Few studies have investigated the association of dysglycemia and incident AF. We investigated the risk of incident AF and prognosis according to diabetes status.

RESEARCH DESIGN AND METHODS

The Copenhagen Primary Care Laboratory Database was merged with data on medical prescriptions, in- and outpatient contacts and vital status. The risk of AF according to diabetes status was investigated by use of Cox regression models.

RESULTS

Of 354.807 individuals with a hemoglobin A1c (HbA1c) measurement, 28.541 (8 %) had known diabetes, 13.038 (4 %) had new onset diabetes and 27.754 (8 %) had prediabetes (HbA1c 42-47 mmol/mol). Persons with dysglycemia (HbA1c > 42 mmol/mol) and diabetes were older, more were men, they had lower level of education and were more likely to be living alone. We observed a gradual increase in risk of developing AF from HbA1c levels of 40 to 60 mmol/mol. In adjusted analyses we found a stepwise increase in hazard of AF from normoglycemia over prediabetes to persons with diabetes (no diabetes: 1.00 [ref.]; prediabetes: 1.12 [1.08-1.16]; new-onset diabetes: 1.16 [1.10-1.22]; known diabetes: 1.15 [1.11-1.20]). Persons with known diabetes had a significant higher hazard of stroke, cardiovascular and all-cause mortality.

CONCLUSION

Increasing levels of HbA1c were associated with an increased hazard of developing AF. Persons with new onset of diabetes and those with known diabetes had similar hazard of developing AF, however persons with known diabetes had a significant higher hazard of stroke, cardiovascular- and all-cause mortality.

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.

Analysis of age-dependent gene-expression in human tissues for studying diabetes comorbidities

The study of the relationship between type 2 diabetes mellitus (T2DM) disease and other pathologies (comorbidities), together with patient age variation, poses a challenge for medical research. There is evidence that patients affected by T2DM are more likely to develop comorbidities as they grow older. Variation of gene expression can be correlated to changes in T2DM comorbidities insurgence and progression. Understanding gene expression changes requires the analysis of large heterogeneous data at different scales as well as the integration of different data sources into network medicine models. Hence, we designed a framework to shed light on uncertainties related to age effects and comorbidity by integrating existing data sources with novel algorithms. The framework is based on integrating and analysing existing data sources under the hypothesis that changes in the basal expression of genes may be responsible for the higher prevalence of comorbidities in older patients. Using the proposed framework, we selected genes related to comorbidities from existing databases, and then analysed their expression with age at the tissues level. We found a set of genes that changes significantly in certain specific tissues over time. We also reconstructed the associated protein interaction networks and the related pathways for each tissue. Using this mechanistic framework, we detected interesting pathways related to T2DM whose genes change their expression with age. We also found many pathways related to insulin regulation and brain activities, which can be used to develop specific therapies. To the best of our knowledge, this is the first study that analyses such genes at the tissue level together with age variations.

Association of type 1 diabetes mellitus and risk of atrial fibrillation: Systematic review and meta-analysis

AIM

Whether type 1 diabetes mellitus (T1DM) could be regarded as an independent risk factor for atrial fibrillation (AF) risk remains unclear, and thus we aimed to elaborate on this association in our meta-analysis.

METHODS

We systematically searched the Pubmed, Embase, Cochrane Library and Web of Science databases up to August 2022 for studies that were related to T1DM and AF incidence. Hazard ratios (HRs) and 95% confidence intervals (CIs) from each study were pooled via a random-effects model.

RESULTS

A total of four cohort studies were involved in our meta-analysis. Our pooled results suggested that T1DM patients had a higher AF risk (HR = 1.30, 95%CI 1.15-1.47) than the control group. In the subgroup analysis, a higher AF incidence was also found in female T1DM patients (HR = 1.50, 95%CI 1.26-1.79) than that in male patients. Compared with T1DM patients over 65 years, those with < 65 years showed an increased risk of AF (HR = 1.45, 95%CI 1.21-1.74).

CONCLUSIONS

Our meta-analysis demonstrated that T1DM was an independent risk factor for AF development, but further studies should be performed to provide more convincing evidence.

Prevalence and incidence of cardiovascular and renal diseases in type 1 compared with type 2 diabetes: A nationwide French observational study of hospitalized patients

BACKGROUND

Type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) increase risks of cardiovascular (CV) and renal disease compared with diabetes-free populations. There are only a few studies comparing T1DM and T2DM for the relative risk of these clinical events.

METHODS

All adult patients hospitalized in French hospitals in 2013 with at least 5 years of follow-up were identified and categorized by their diabetes status. A total of 50,623 patients with T1DM (age 61.4 ± 18.6, 53% male) and 425,207 patients with T2DM (age 68.6 ± 14.3, 55% male) were followed over a median period of 5.3 years (interquartile range: 2.8 - 5.8 years). Prevalence and event rates of myocardial infarction (MI), heart failure (HF), ischemic stroke, chronic kidney disease (CKD), all-cause death and CV death were assessed with age stratification of 10-year intervals. For clinical events during follow-up, we report hazard ratios (HRs) in T1DM relative to T2DM.

RESULTS

The age and sex-adjusted prevalence of CV diseases was higher in T2DM for ages above 40 years whereas the prevalence of CKD was more common in T1DM between ages 18 and 70 years. During 2,033,239 person-years of follow-up, age and sex-adjusted HR event rates comparing T1DM, versus T2DM as reference, showed that MI and HF relative risks were increased above 60 years (1.2 and 1.4 -fold). HR of ischemic stroke did not markedly differ between T1DM and T2DM. Risk of incident CKD was 2.4-fold higher in T1DM above 60 years. All-cause death HR risk was 1.1-fold higher in T1DM after 60 years and the CV death risk was 1.15-fold higher in T1DM between 60 and 69 years compared to T2DM.

CONCLUSIONS

Although the crude prevalent burden of CV diseases may be lower in T1DM than in T2DM, patients with T1DM may have a higher risk of incident MI, HF, all-cause death and CV death above 60 years of age, highlighting the need for improved prevention in this population.

The complex interplay between diabetes mellitus and atrial fibrillation

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

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

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

A touch-actuated glucose sensor fully integrated with microneedle array and reverse iontophoresis for diabetes monitoring

The development of non-invasive biosensor for monitoring glucose in interstitial fluid (ISF) is still challenging, because ISF extraction through classical reverse iontophoresis (RI) is limited by low extraction flux and consistency. Here, we developed a touch-actuated biosensor for monitoring glucose in ISF. The biosensor is composed of three main components: 1) the solid microneedle array (MA) for painless skin penetration; 2) the RI unit for ISF extraction through the MA-created microchannels; and 3) the sensing unit for glucose monitoring. The sensing strategy of this biosensor is "skin penetration-RI extraction-electrochemical detection". Compared with RI extraction only, the reported skin penetration-RI extraction sampling strategy obviously increased the glucose extraction flux by ∼1.6 times not only in vitro but also in vivo. Moreover, we developed a wearable glucose monitoring system by incorporating this touch-actuated biosensor, a wireless electrochemical detector, and a smartphone application. In vivo experiments using healthy and diabetic rats revealed a high correlation between the results measured by the reported wearable system and commercially blood glucometer. This sampling strategy which combined skin penetration and RI extraction paves the way to develop wearable platforms for not only glucose monitoring but also various ISF biomarkers without the need of painful finger-stick blood sampling.

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.

Metabolically healthy obesity and cardiovascular events: A nationwide cohort study

AIM

To evaluate the associations between metabolically healthy obesity (MHO) and different types of incident cardiovascular events in a contemporary population.

MATERIALS AND METHODS

All patients discharged from French hospitals in 2013 with at least 5 years of follow-up and without a history of major adverse cardiovascular event (MACE; myocardial infarction, heart failure [HF], ischaemic stroke or cardiovascular death [MACE-HF]) or underweight/malnutrition were identified. They were categorized by phenotypes defined by obesity and three metabolic abnormalities (diabetes, hypertension and hyperlipidaemia). Hazard ratios (HRs) for cardiovascular events during follow-up were adjusted on age, sex and smoking status at baseline.

RESULTS

In total, 2 873 039 individuals were included in the analysis, among whom 272 838 (9.5%) had obesity. During a mean follow-up of 4.9 years, when pooling men and women, individuals with MHO had a higher risk of MACE-HF (multivariate-adjusted HR 1.22, 95% confidence interval [CI]: 1.19-1.24), new-onset HF (HR 1.34, 95% CI 1.31-1.37) and atrial fibrillation (AF; HR 1.33, 95% CI 1.30-1.37) compared with individuals with no obesity and zero metabolic abnormalities. By contrast, risks were not higher for myocardial infarction (HR 0.92, 95% CI 0.87-0.98), ischaemic stroke (HR 0.93, 95% CI 0.88-0.98) and cardiovascular death (HR 0.99, 95% CI 0.93-1.04). MHO in men was associated with a higher risk of clinical events compared with metabolically healthy men of normal weight (HR 1.12-1.80), while women with MHO had a lower risk for most events than metabolically healthy women of normal weight (HR 0.49-0.99).

CONCLUSIONS

In a large and contemporary analysis of patients seen in French hospitals, individuals with MHO did not have a higher risk of myocardial infarction, ischaemic stroke or cardiovascular death than metabolically healthy individuals with no obesity. By contrast, they had a higher risk of new-onset HF and new-onset AF. However, notable differences were observed in men and women in the sex-stratified analysis.

Sodium-Glucose Co-Transporter Inhibitors and Atrial Fibrillation: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Sodium‐glucose co‐transporter (SGLT) inhibitors reduce cardiovascular outcomes including mortality in several populations; however, their effect on atrial fibrillation/flutter (AF) remains unclear. Our objective was to determine whether SGLT inhibitors reduce AF and whether a history of AF modifies the effect of SGLT inhibitors on the composite of heart failure hospitalization or cardiovascular death.

Methods and Results

We searched MEDLINE, Embase, and CENTRAL to March 2021. Pairs of reviewers identified randomized controlled trials that compared an SGLT inhibitor with placebo or no therapy. We pooled data using RevMan 5.4.1, assessed risk of bias using the Cochrane tool, and determined the overall quality of evidence using Grades of Recommendation, Assessment, Development and Evaluation. Thirty‐one eligible trials reported on AF events (75 279 participants, mean age 62 years, 35.0% women). Moderate quality evidence supported a lower risk of serious AF events with SGLT inhibitors (1.1% versus 1.5%; risk ratio 0.75 [95% CI, 0.66–0.86]; I²=0%). A similar reduction in total AF events was also noted with SGLT inhibitors. Three trials reported on heart failure hospitalization/cardiovascular death stratified by a baseline history of AF (18 832 participants, mean age 66 years, 38.1% women); in patients with a history of AF, SGLT inhibitors resulted in a lower risk in the composite of heart failure hospitalization or cardiovascular death (hazard ratio, 0.70 [95% CI, 0.57–0.85]; I²=0%)—similar to the effect estimate for patients without AF, P value for interaction: 1.00.

Conclusions

SGLT inhibitors may reduce AF events and likely reduce heart failure hospitalization/cardiovascular death to a similar extent in patients with and without AF.