Resting heart rate and the risk of death and cardiovascular complications in patients with type 2 diabetes mellitus

Physiological effects of ivabradine in heart failure and beyond

Ivabradine is a pharmacologic agent that inhibits the funny current responsible for determining heart rate in the sinoatrial node. Ivabradine's clinical potential has been investigated in the context of heart failure since it is associated with reduced myocardial oxygen demand, enhanced diastolic filling, stroke volume, and coronary perfusion time; however, it is yet to demonstrate definitive mortality benefit. Alternative effects of ivabradine include modulation of the renin-angiotensin-aldosterone system, sympathetic activation, and endothelial function. Here, we review key clinical trials informing the clinical use of ivabradine and explore opportunities for leveraging its potential pleiotropic effects in other diseases, including treatment of hyperadrenergic states and mitigating complications of COVID-19 infection.

Exploring the contribution of inter-individual factors to the development of physiological heat strain in older adults exposed to simulated indoor overheating

Older adults are at elevated risk of heat-related mortality due to age-associated declines in thermoregulatory and cardiovascular function. However, the inter-individual factors that exacerbate physiological heat strain during heat exposure remain unclear, making it challenging to identify more heat-vulnerable subgroups. We therefore explored factors contributing to inter-individual variability in physiological responses of older adults exposed to simulated hot weather. Thirty-seven older adults (61-80 years, 16 females) rested for 8 h in 31 and 36 °C (45% relative humidity). Core (rectal) temperature, heart rate (HR), HR variability, mean arterial pressure (MAP), and cardiac autonomic responses to standing were measured at baseline and end-exposure. Bootstrapped least absolute shrinkage and selection operator regression was used to evaluate whether variation in these responses was related to type 2 diabetes (T2D, n = 10), hypertension (n = 18), age, sex, body morphology, habitual physical activity levels, and/or heat-acclimatization. T2D was identified as a predictor of end-exposure HR (with vs. without: 13 beats/min (bootstrap 95% confidence interval: 6, 23)), seated MAP (-7 mmHg (-18, 1)), and the systolic pressure response to standing (20 mmHg (4, 36)). HR was also influenced by sex (female vs. male: 8 beats/min (1, 16)). No other predictors were identified. The inter-individual factors explored did not meaningfully contribute to the variation in body temperature responses in older adults exposed to simulated indoor overheating. By contrast, cardiovascular responses were exacerbated in females and individuals with T2D. These findings improve understanding of how inter-individual differences contribute to heat-induced physiological strain in older persons.

Reliability of heart rate in reflecting cardiac sympathetic overdrive in type 2 diabetes mellitus

PURPOSE

Clinical trials have shown that in type 2 diabetes mellitus (T2D) resting office heart rate (HR) values > 70 beats/minute are associated with an increased cardiovascular risk, a worse prognosis and an unfavorable outcome. The present study was aimed at investigating whether the above mentioned treshold HR values reflect a sympathetic overdrive of marked degree.

METHODS

In 58 T2D patients (age range: 39-57 years) without signs of autonomic neuropathy and in 52 age-matched healthy controls, we assessed muscle sympathetic nerve activity (MSNA, microneurography) and venous plasma norepinephrine (NE, HPLC), subdividing the study population in different subgroups according to their clinic and 24-h HR values.

RESULTS

In T2D progressively greater clinic and 24-h HR values were accompanied by progressive increases in MSNA and NE. HR cutoff values indicated by clinical trials as associated with an increased cardiovascular risk (> 70 beats/minute) were accompanied by MSNA values significantly higher than those detected in patients with lower HR, this being the case also for NE. In T2D both MSNA and NE were significantly related to clinic (r = 0.93, P < 0.0001 and r = 0.87, P < 0.0001, respectively) and 24-h (r = 0.92, P < 0.0001 and r = 0.84, P < 0.0001, respectively) HR. The MSNA and NE behaviour observed in T2D was not detected in healthy controls.

CONCLUSIONS

In T2D clinic HR values allow to detect patients with a greater sympathetic overactivity. Considering the adverse clinical impact of the sympathetic overdrive on prognosis, our data emphasize the need of future studies investigating the potential usefulness of lifestyle and pharmacological interventions exerting sympathomodulatory effects.

Electrocardiographic markers in patients with type 2 diabetes and the role of diabetes duration

BACKGROUND

The association between type 2 diabetes and electrocardiographic (ECG) markers are incompletely explored and the dependence on diabetes duration is largely unknown. We aimed to investigate the electrocardiographic (ECG) changes associated with type 2 diabetes over time.

METHODS

In this cross-sectional study, we matched people with type 2 diabetes 1:1 on sex, age, and body mass index with people without diabetes from the general population. We regressed ECG markers with the presence of diabetes and the duration of clinical diabetes, respectively, adjusted for sex, age, body mass index, smoking, heart rate, diabetes medication, renal function, hypertension, and myocardial infarction.

RESULTS

We matched 988 people with type 2 diabetes (332, 34% females) with as many controls. Heart rate was 8 bpm higher (p < 0.001) in people with vs. without type 2 diabetes, but the difference declined with increasing diabetes duration. For most depolarization markers, the difference between people with and without type 2 diabetes increased progressively with diabetes duration. On average, R-wave amplitude was 6 mm lower in lead V5 (p < 0.001), P-wave duration was 5 ms shorter (p < 0.001) and QRS duration was 3 ms (p = 0.03). Among repolarization markers, T-wave amplitude (measured in V5) was lower in patients with type 2 diabetes (1 mm lower, p < 0.001) and the QRS-T angle was 10 degrees wider (p = 0.002). We observed no association between diabetes duration and repolarization markers.

CONCLUSIONS

Type 2 diabetes was independently associated with electrocardiographic depolarization and repolarization changes. Differences in depolarization markers, but not repolarization markers, increased with increasing diabetes duration.

Effects of temporal changes in resting heart rate on future diabetes-related outcomes

Background and aims

Most studies have analyzed the relationship between resting heart rate (RHR) measured at only one time point and future clinical events. The current study aims to investigate the impact of long-term RHR changes on future clinical outcomes in a decade-long cohort with type 2 diabetes mellitus (T2DM).

Methods

The two-staged follow-up involved 2,513 T2DM participants. The first stage (2008-2014) intended to identify levels and trends in RHR changes, while the second stage (2014-2018) attempted to collect new occurrence records of clinical results. Cox proportional hazards models were applied to predict hazard ratios (HRs), along with 95% confidence interval (CI) for the correlation between RHR changes and future events.

Results

There is no significant correlation between baseline RHR levels and long-term clinical events. According to the range of RHR change, compared with the stable RHR group, the adjusted HRs for cardiovascular events and all-cause death in the large increase group were 3.40 (95% CI: 1.33-8.71, p=0.010) and 3.22 (95% CI: 1.07-9.64, p=0.037), respectively. While the adjusted HRs for all-cause death and major adverse cardiac and cerebrovascular events (MACCE) in the moderate decrease group were 0.55 (95% CI: 0.31-0.96, p=0.037) and 0.51 (95% CI: 0.26-0.98, p=0.046). According to the trend of RHR, compared with the normal-normal group, the adjusted HRs for composite endpoint events and cerebrovascular events in the normal-high group were 1.64 (95% CI: 1.00-2.68, p=0.047) and 2.82 (95% CI: 1.03-7.76, p=0.043), respectively.

Conclusion

Changes in RHR had predictive value for long-term clinical events in diabetic populations. Individuals with significantly elevated RHR over a particular period of time showed an increased risk of adverse events.

Prevalence and predictors of female sexual dysfunction among sexually active women in the diabetes prevention program outcomes study

OBJECTIVE

To determine the burden and identify correlates of female sexual dysfunction (FSD) among women with prediabetes (PreD) and type 2 diabetes (T2D) enrolled in the Diabetes Prevention Program (DPP) Outcomes Study (DPPOS).

METHODS

The DPPOS visit included the Female Sexual Function Index (FSFI) to determine sexual function. Of 1464 participants, 1320 (90%) completed the (FSFI) and 426 were sexually active. A backward selection multivariable logistic regression model estimated the odds of FSD for sociodemographic, clinical, and diabetes-related covariates.

RESULTS

One hundred and eighty-five (43%) had a score of ≤26.55 and met the criteria for FSD. After adjustment for DPP treatment and age, urinary incontinence (UI) (odds ratio [OR] = 1.91, 95% confidence interval [CI] = 1.15-3.17) and hysterectomy (OR = 1.89, 95% CI = 1.01-3.53) were associated with increased odds of FSD. Increased body mass index was protective for FSD (OR = 0.93 per kg/m2, 95% CI = 0.89-0.96). Michigan Neuropathy Screening Instrument-based peripheral neuropathy (mean±SD scores 1.1±1.3 vs. 0.9±1.1, p < 0.0001) and Electrocardiogram (ECG)-based autonomic dysfunction measures (mean ± SD heart rate levels 64.3 ± 6.8 vs. 65.6 ± 10.2, p = 0.008) were associated with FSD. There were no differences in diabetes rates between women who did (66.5%) and did not (66%) have (p = 0.7).

CONCLUSIONS

FSD is prevalent in women with PreD and T2D. Our findings suggest that FSD is associated with neuropathic complications commonly observed in PreD and T2D.

The Importance of Evaluating Sudomotor Function in the Diagnosis of Cardiac Autonomic Neuropathy

INTRODUCTION

 Cardiac autonomic neuropathy (CAN) is a disorder affecting the autonomic nerves that regulate the cardiovascular system, leading to irregular heart rate and blood pressure control. It is commonly associated with diabetes mellitus but can also result from other conditions such as autoimmune disorders, chronic kidney disease, alcohol abuse, and certain medications. Screening for CAN is essential, particularly in individuals with poor glycemic control, cardiovascular risk factors, or complications. Early identification of CAN is vital for timely intervention to prevent or manage cardiovascular complications effectively. Regular screening helps detect CAN before symptoms emerge, enabling early intervention to slow or halt its progression. This study examined the relationship between sudomotor function and cardiovascular reflex tests.

MATERIAL AND METHODS

 This was a cross-sectional study conducted between June 2019 and June 2020. The study included 271 subjects aged 18 years and above who provided informed consent, were diagnosed with type 2 diabetes mellitus (T2DM), and were overweight or obese. Exclusion criteria encompassed patients with other types of diabetes, pregnant women, those with recent neoplasm diagnoses, stroke sequelae, history of myocardial infarction, or pelvic limb amputations. The assessment of cardiac autonomic neuropathy involved conducting an electrocardiogram and evaluating the QTc interval in the morning before taking medication. Additionally, cardiovascular reflex tests (CART) were conducted, including assessments of heart rate variability during deep breathing, the Valsalva maneuver, and changes in orthostatic position. Simultaneously, the diagnosis of CAN was assessed by performing a sweat test using a Sudoscan assessment (Impeto Medical, Moulineaux, France).  Results: More than half of the participants (52%, n=143) were female. Significant differences in statistical measures were noted between females and males regarding age, systolic blood pressure, fasting blood glucose, A1c level, total cholesterol, triglycerides, gamma-glutamyl transferase, and bilirubin levels. Within the CAN-diagnosed group (CAN+), 40.92% were classified as mild cases (n=90), 47.27% as moderate cases (n=104), and 11.81% as severe cases (n=26). Among the CAN+ group, 54% (n=119) were women. Electrochemical skin conductance was lower in the CAN+ group than the CAN- group in hands (67.34±15.51 μS versus 72.38±12.12 μS, p=0.008) and feet (73.37±13.38 μS versus 82.84 ±10.29 μS, p<0.001). The Sudoscan-CAN score significantly correlated with Ewing scores (r= 0.522, p<0.001). In multiple linear regression analysis, the Sudoscan-CAN score remained significantly associated with age, high BMI, long-standing diabetes, and Ewing score.

CONCLUSIONS

 Sudoscan demonstrates potential in identifying patients with an increased risk of CAN. Its integration into clinical practice can improve patient outcomes through early detection, risk stratification, and personalized treatment approaches. Its non-invasive, portable, and user-friendly features render it suitable for utilization in outreach programs or resource-constrained settings as part of screening efforts designed to pinpoint high-risk individuals for additional assessment.

Interplay of heart rate variability and resting heart rate on mortality in type 2 diabetes

AIMS

Heart rate variability (HRV) and resting heart rate (RHR) are usually analyzed and interpreted separately. We aimed to assess the interplay of HRV and RHR on mortality in type 2 diabetes.

METHODS

The study included 7,529 participants from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. HRV metrics included standard deviation of all normal-to-normal intervals (SDNN) and root mean square of successive differences between normal-to-normal intervals (rMSSD). Abnormal values were defined based on <25th percentile for HRV and >75th percentile for RHR. Interactions of HRV status and RHR status were tested on multiplicative and additive scales. Results were validated in a subset of patients with type 2 diabetes (n = 745) from the Multi-Ethnic Study of Atherosclerosis.

RESULTS

Low SDNN was associated with increased all-cause mortality in the high RHR group (HR 1.60; 95% CI 1.29-1.97), but not in the normal RHR group. Compared with those who had neither low SDNN nor high RHR, the presence of either low SDNN or high RHR was not significantly associated with an increased risk of all-cause mortality. In contrast, the combination of low SDNN and high RHR was associated with a significantly increased risk of all-cause mortality (HR 1.68; 95% CI 1.43-1.97). Significant multiplicative and additive interactions were found between HRV status and RHR status on risk of all-cause mortality (all Pinteraction < 0.05). Similar findings were observed for cardiovascular mortality, in analyses using rMSSD, and in the Multi-Ethnic Study of Atherosclerosis.

CONCLUSIONS

The association between HRV and mortality risk is modified by RHR levels. Furthermore, low HRV and high RHR have interdependent and synergistic associations with mortality risk.

G protein-coupled receptors and obesity

G protein-coupled receptors (GPCRs) have emerged as important drug targets for various chronic diseases, including obesity and diabetes. Obesity is a complex chronic disease that requires long term management predisposing to type 2 diabetes, heart disease, and some cancers. The therapeutic landscape for GPCR as targets of anti-obesity medications has undergone significant changes with the approval of semaglutide, the first peptide glucagon like peptide 1 receptor agonist (GLP-1RA) achieving double digit weight loss (≥10%) and cardiovascular benefits. The enhanced weight loss, with the expected beneficial effect on obesity-related complications and reduction of major adverse cardiovascular events (MACE), has propelled the commercial opportunity for the obesity market leading to new players entering the space. Significant progress has been made on approaches targeting GPCRs such as single peptides that simultaneously activate GIP and/or GCGR in addition to GLP1, oral tablet formulation of GLP-1, small molecules nonpeptidic oral GLP1R and fixed-dose combination as well as add-on therapy for patients already treated with a GLP-1 agonist.

Resting Heart Rate Independent of Cardiovascular Disease Risk Factors Is Associated With End-Stage Renal Disease: A Cohort Study Based on 476 347 Adults

BACKGROUND

The relationship between resting heart rate (RHR) and the risk of end-stage renal disease (ESRD) among those without cardiovascular disease remains unclear. We aim to establish temporal consistency and elucidate the independent relationship between RHR and the risk of ESRD.

METHODS AND RESULTS

This cohort enrolled participants from 476 347 individuals who had taken part in a screening program from 1996 to 2017. We identified 2504 participants who had ESRD, and the median follow-up was 13 years. RHR was extracted from electrocardiography results, and the study assessed the relationship between RHR and the risk of ESRD using the Cox proportional hazards model. Of the participants, 32.6% had an RHR of 60 to 69 beats per minute (bpm), and 22.2% had an RHR of ≥80 bpm. Participants with an RHR of ≥80 bpm had a higher stage of chronic kidney disease, lower estimated glomerular filtration rate, and more proteinuria than those with an RHR of 60 to 69 bpm. Participants with an RHR of 80 to 89 and ≥90 bpm had a 24% (hazard ratio [HR], 1.24 [95% CI, 1.09-1.42]) and 64% (HR, 1.64 [95% CI, 1.42-1.90]) higher risk of ESRD, respectively. The risk of ESRD remained significantly elevated (HR, 1.32 [95% CI, 1.10-1.58] per 10-beat increase from 60 bpm) after excluding participants who smoked; had hypertension, diabetes, or hyperlipidemia; or were overweight.

CONCLUSIONS

An RHR of ≥80 bpm is significantly associated with an increased risk of ESRD. These results suggest that RHR may serve as a risk factor for kidney disease in individuals without established cardiovascular disease risk factors.

Bariatric Surgery for Adults With Class I Obesity and Difficult-to-Manage Type 2 Diabetes: A Health Technology Assessment

Background

Many individuals with type 2 diabetes are classified as either overweight or obese. A patient may be described as having difficult-to-manage type 2 diabetes if their HbA1c levels remain above recommended target levels, despite efforts to treat it with lifestyle changes and pharmacotherapy. Bariatric surgery refers to procedures that modify the gastrointestinal tract. In patients with class II or III obesity, bariatric surgery has resulted in substantial weight loss, improved quality of life, reduced mortality risk, and resolution of type 2 diabetes. There is some evidence suggesting these outcomes may also be possible for patients with class I obesity as well. We conducted a health technology assessment of bariatric surgery for adults with class I obesity and difficult-to-manage type 2 diabetes, which included an evaluation of effectiveness, safety, cost-effectiveness, the budget impact of publicly funding bariatric surgery, and patient preferences and values.

Methods

We performed a systematic clinical literature review. We assessed the risk of bias of each included study, using the Cochrane Risk of Bias tool for randomized controlled trials, the Risk of Bias in Non-randomized Studies - of Interventions (ROBINS-I) tool for cohort studies, and the Risk of Bias in Systematic Reviews (ROBIS) tool for systematic reviews; we assessed the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We performed a systematic economic literature review and conducted a cost-utility analysis of bariatric surgery in comparison with nonsurgical usual care over a lifetime horizon from a public payer perspective. We also analyzed the budget impact of publicly funding bariatric surgery for adults with class I obesity and difficult-to-manage type 2 diabetes in Ontario. To contextualize the potential value of bariatric surgery, we spoke with people with obesity and type 2 diabetes who had undergone or were considering this procedure.

Results

We included 14 studies in the clinical evidence review. There were large increases in diabetes remission rates (GRADE: Low to Very low) and large reductions in body mass index (GRADE: Low to Very low) with bariatric surgery than with medical management. Bariatric surgery may also reduce the use of medications for type 2 diabetes (GRADE: Low) and may improve quality of life for people with class I obesity and difficult-to-manage type 2 diabetes compared with medical management. (GRADE: Low)Our economic evidence review included 5 cost-effectiveness studies; none were conducted in a Canadian setting, and 4 were considered partially applicable to our research question. Most studies found bariatric surgery to be cost-effective compared to standard care for patients with class I obesity and type 2 diabetes; however, the applicability of these results to the Ontario context is uncertain due to potential differences in clinical practice, resource utilization, and unit costs.Our primary economic evaluation found that over a lifetime horizon, bariatric surgery was more costly (incremental cost: $8,151 per person) but also more effective than current usual care (led to a 0.339 quality-adjusted life-year [QALY] gain per person). The cost increase was driven by costs associated with surgery (before, after, and during surgery), and the QALY gain was due to life-years gained. Results were sensitive to the bariatric surgery cost and assumptions regarding its long-term benefits with respect to weight loss and diabetes remission.Publicly funding 50 bariatric surgeries in year 1, and gradually increasing to 250 surgeries in year 5, for people with class I obesity and difficult-to-manage type 2 diabetes would lead to budget increases of $0.55 million in year 1 to $2.45 million in year 5, for a total of $7.63 million over 5 years.The people with obesity and type 2 diabetes with whom we spoke reported that bariatric surgery was generally seen as a positive treatment option, and those who had undergone the procedure reported positively on its value as a treatment to manage their weight and diabetes.

Conclusions

For adults with class I obesity and difficult-to-manage type 2 diabetes, bariatric surgery may be more clinically effective and cost-effective than medical management. Compared with medical management in people with class I obesity and difficult-to-manage type 2 diabetes, bariatric surgery may result in large increases in diabetes remission rates, large reductions in BMI, and reduced medication use for type 2 diabetes, improved quality of life. Over a lifetime horizon, bariatric surgery led to a cost increase and QALY gain. Bariatric surgery can result in postsurgical complications that are not faced by those receiving medical management. The cost-effectiveness of bariatric surgery depends on its long-term impacts on obesity-related and diabetes-related complications, which could be uncertain.Our budget impact analysis suggests that publicly funding bariatric surgery in Ontario for people with class I obesity and difficult-to-manage type 2 diabetes would lead to a budget increase of $7.63 million over 5 years.For people with obesity and type 2 diabetes, bariatric surgery was seen as a potential positive treatment option to manage their weight and diabetes.

Association of Resting Heart Rate Trajectories With Cardiovascular Disease and Mortality in Patients With Diabetes Mellitus

CONTEXT

Longitudinal patterns of resting heart rate (RHR) in patients with diabetes mellitus and their association with health outcomes are not well-characterized.

OBJECTIVE

We sought to explore the RHR trajectories in patients with diabetes mellitus and their association with cardiovascular disease (CVD) and all-cause mortality.

DESIGN

The Kailuan Study is a prospective cohort study. Participants underwent health examinations biennially starting in 2006 and were followed until December 31, 2020.

SETTING

General community.

PARTICIPANTS

A total of 8218 diabetic participants who attended at least 3 of the examinations conducted in 2006, 2008, 2010, and 2012 were included.

MAIN OUTCOME MEASURES

CVD and all-cause mortality.

RESULTS

We identified 4 RHR trajectories in participants with diabetes mellitus between 2006 and 2012: low-stable (range, 66.83-64.91 beats/min; n = 1705), moderate-stable (range, 76.30-76.95 beats/min; n = 5437), high-decreasing (mean decreased from 92.14 to 85.60 beats/min; n = 862), and high-increasing (mean increased from 84.03 to 111.62 beats/min; n = 214). During an average follow-up of 7.25 years, 977 cases of CVD and 1162 deaths were identified. Compared with the low-stable trajectory, adjusted hazard ratios (HRs) for CVD were 1.48 (95% CI, 1.02-2.14; P = .04) for the high-increasing trajectory, adjusted HRs for all-cause mortality were 1.34 (95% CI, 1.14-1.58; P < .01) for the moderate-stable trajectory, 1.68 (95% CI, 1.35-2.10; P < .01) for the high-decreasing trajectory, and 2.47 (95% CI, 1.85-3.31; P < .01) for the high-increasing trajectory.

CONCLUSIONS

RHR trajectories were associated with the subsequent risks of CVD and all-cause mortality in patients with diabetes mellitus.

High blood pressure with elevated resting heart rate: a high risk "Sympathetic" clinical phenotype

Epidemiological studies have unequivocally shown that elevated heart rate values measured at rest have an adverse prognostic impact in the hypertensive patient, being associated with an increased risk of cardiovascular events and complications. In recent years new data have been collected on this issue, strengthening the clinical relevance of elevated heart rate as a specific hypertensive phenotype. The present paper will review old and new data on the prognostic importance of resting tachycardia in the hypertensive patient. It will also examine the role of the sympathetic nervous system in the development of this alteration as well as its therapeutic implications. The different approaches to dynamically assess heart rate values in the clinical setting will be finally discussed.

Optimal Heart Rate Control Improves Long-Term Prognosis of Decompensated Heart Failure with Reduced Ejection Fraction

Background and Objectives: An elevated heart rate is an independent risk factor for cardiovascular disease; however, the relationship between heart rate control and the long-term outcomes of patients with heart failure with reduced ejection fraction (HFrEF) remains unclear. This study explored the long-term prognostic importance of heart rate control in patients hospitalized with HFrEF. Materials and Methods: We retrieved the records of patients admitted for decompensated heart failure with a left ventricular ejection fraction (LVEF) of ≤40%, from 1 January 2005 to 31 December 2019. The primary outcome was a composite of cardiovascular death or hospitalization for heart failure (HHF) during follow-up. We analyzed the outcomes using Cox proportional hazard ratios calculated using the patients' heart rates, as measured at baseline and approximately 3 months later. The mean follow-up duration was 49.0 ± 38.1 months. Results: We identified 5236 eligible patients, and divided them into five groups on the basis of changes in their heart rates. The mean LVEFs of the groups ranged from 29.1% to 30.6%. After adjustment for all covariates, the results demonstrated that lesser heart rate reductions at the 3-month screening period were associated with long-term cardiovascular death, HHF, and all-cause mortality (p for linear trend = 0.033, 0.042, and 0.003, respectively). The restricted cubic spline model revealed a linear relationship between reduction in heart rate and risk of outcomes (p for nonlinearity > 0.2). Conclusions: Greater reductions in heart rate were associated with a lower risk of long-term cardiovascular death, HHF, and all-cause mortality among patients discharged after hospitalization for decompensated HFrEF.

A higher resting heart rate is associated with cardiovascular event risk in patients with type 2 diabetes mellitus without known cardiovascular disease

A higher resting heart rate (RHR) is associated with an increased risk of cardiovascular events in patients with type 2 diabetes mellitus (T2DM) and cardiovascular diseases. The aim of this study was to investigate the association between RHR and cardiovascular events in T2DM patients with diabetic retinopathy and without known cardiovascular disease. We analyzed the association between RHR and cardiovascular events, including coronary, cerebral, renal and vascular events or cardiovascular death in T2DM patients with retinopathy and hyperlipidemia without prior cardiovascular events who were enrolled in the EMPATHY study. Data from 4746 patients were analyzed. The median RHR was 76 bpm. Patients were divided into four groups based on their baseline RHR ( < 60, 60-69, 70-79, and ≥80 bpm). Patients with a higher RHR were more likely to be younger and had a higher body mass index, blood pressure value, HbA1c value, and estimated glomerular filtration rate and a lower B-type natriuretic peptide value; they also had a higher proportion of current smoking status, neuropathy, and nephropathy. After adjusting for confounders, including the aforementioned risk factors, a RHR of 70-79 bpm and a RHR ≥ 80 bpm were significantly associated with cardiovascular events (hazard ratio 1.50, 95% CI 1.03-2.20; and hazard ratio 1.62, 95% CI 1.11-2.36; respectively) compared to a RHR of 60-69 bpm. The analysis using restricted cubic splines indicated that the cardiovascular risk seemed to be similarly high when the RHR range was ≥70 bpm. In conclusion, in T2DM patients with diabetic retinopathy and without known cardiovascular disease, a high RHR, particularly ≥70 bpm, was associated with the risk of cardiovascular events compared to a RHR of 60-69 bpm. High resting heart rate (RHR), particularly ≥70 bpm, was associated with the risk of cardiovascular events compared to RHR 60-69 bpm in patients with type 2 diabetes mellitus (T2DM), diabetic retinopathy, and hyperlipidemia, but without known cardiovascular disease.

Impact of Diabetes Mellitus and Its Comorbidities on Elderly Patients Hospitalized in Internal Medicine Wards: Data from the RePoSi Registry

BACKGROUND

Currently, diabetes represents the seventh leading cause of death worldwide, with a significant economic burden. The number and severity of comorbidities increase with age, and are identified as important determinants that influence the prognosis. We aimed to investigate comorbidities and outcomes in a cohort of hospitalized elderly patients affected by diabetes.

METHODS

In this observational study, we retrospectively analyzed data collected from the REgistro dei pazienti per lo studio delle POlipatologie e politerapie in reparti della rete Simi (RePoSi) registry. Socio-demographic, clinical characteristics, and laboratory findings were considered. The association between variables and in-hospital and 1-year follow-up were analyzed.

RESULTS

Among 4708 in-patients, 1378 (29.3%) had a diagnosis of diabetes. Patients with diabetes had more previous hospitalization, a clinically significant disability, and more need for a urinary catheter in comparison with subjects without diabetes. Patients affected by diabetes took more drugs, both at admission, at in-hospital stay, at discharge, and at 1-year follow-up. Thirty-five comorbidities were more frequent in patients with diabetes, and the first five were hypertension (57.1%), ischemic heart disease (31.4%), chronic renal failure (28.8%), atrial fibrillation (25.6%), and chronic obstructive pulmonary disease (22.7%). Heart rate was an independent predictor of in-hospital mortality. At 1-year follow-up, cancer and male sex were strongly independently associated with mortality.

CONCLUSIONS

Our findings showed the severity of the impact of diabetes and its comorbidities in the real life of internal medicine and geriatric wards, and provide data to be used for a better tailored management of elderly in-patients with diabetes.

Structural and Electrical Remodeling of the Sinoatrial Node in Diabetes: New Dimensions and Perspectives

The sinoatrial node (SAN) is composed of highly specialized cells that mandate the spontaneous beating of the heart through self-generation of an action potential (AP). Despite this automaticity, the SAN is under the modulation of the autonomic nervous system (ANS). In diabetes mellitus (DM), heart rate variability (HRV) manifests as a hallmark of diabetic cardiomyopathy. This is paralleled by an impaired regulation of the ANS, and by a pathological remodeling of the pacemaker structure and function. The direct effect of diabetes on the molecular signatures underscoring this pathology remains ill-defined. The recent focus on the electrical currents of the SAN in diabetes revealed a repressed firing rate of the AP and an elongation of its tracing, along with conduction abnormalities and contractile failure. These changes are blamed on the decreased expression of ion transporters and cell-cell communication ports at the SAN (i.e., HCN4, calcium and potassium channels, connexins 40, 45, and 46) which further promotes arrhythmias. Molecular analysis crystallized the RGS4 (regulator of potassium currents), mitochondrial thioredoxin-2 (reactive oxygen species; ROS scavenger), and the calcium-dependent calmodulin kinase II (CaMKII) as metabolic culprits of relaying the pathological remodeling of the SAN cells (SANCs) structure and function. A special attention is given to the oxidation of CaMKII and the generation of ROS that induce cell damage and apoptosis of diabetic SANCs. Consequently, the diabetic SAN contains a reduced number of cells with significant infiltration of fibrotic tissues that further delay the conduction of the AP between the SANCs. Failure of a genuine generation of AP and conduction of their derivative waves to the neighboring atrial myocardium may also occur as a result of the anti-diabetic regiment (both acute and/or chronic treatments). All together, these changes pose a challenge in the field of cardiology and call for further investigations to understand the etiology of the structural/functional remodeling of the SANCs in diabetes. Such an understanding may lead to more adequate therapies that can optimize glycemic control and improve health-related outcomes in patients with diabetes.

Cardiac autonomic neuropathy and risk of cardiovascular disease and mortality in type 1 and type 2 diabetes: a meta-analysis

We aimed to determine the prognostic association between cardiac autonomic neuropathy (CAN) and cardiovascular disease events (CVE) and mortality in type 1 and type 2 diabetes through a systematic review and meta-analysis. This systematic review and meta-analysis was registered with PROSPERO (CRD42020216305) and was conducted with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodological criteria. CAN was defined on the basis of 1 (early/possible CAN) or ≥2 (definite CAN) positive autonomic function tests as per the Toronto Consensus guidelines. Studies included those with prospective CVE or mortality data. Methodological variables/risk of bias were assessed using ROBINS-I (Risk Of Bias In Non-randomized Studies - of Interventions) and RoB-2 (Risk-Of-Bias tool for randomized trials) appraisal tools. Electronic database searches yielded 18 467 articles; 84 articles were screened full-text, 26 articles fulfilled the inclusion criteria for quantitative synthesis. Sixteen studies from patients with (n=2875) and without (n=11 722) CAN demonstrated a pooled relative risk (RR) of 3.16 (95%CI 2.42 to 4.13; p<0.0001) of future CVE in favour of CAN. Nineteen studies provided all-cause mortality data from patients with (n=3679) and without (n=12 420) CAN, with a pooled RR of 3.17 (95%CI 2.11 to 4.78; p<0.0001) in favour of CAN. The risk of both future CVE and mortality was higher in type 1 compared with type 2 diabetes and with a definite CAN (vs possible CAN) diagnosis. Three studies were considered to have risk of serious bias. This study confirms the significant association between CAN and CVE and all-cause mortality. The implementation of population-based CAN screening will identify a subgroup with disproportionately higher cardiovascular and mortality risk that will allow for earlier targeted intervention.

Ivabradine Ameliorates Cardiac Diastolic Dysfunction in Diabetic Mice Independent of Heart Rate Reduction

Cardiac fibroblast (CF) proliferation and activation play important roles in cardiac fibrosis and diastolic dysfunction (DD), which are involved in fibrosis-associated cardiovascular diseases. A previous study showed that ivabradine, a specific heart rate (HR)-lowering agent, significantly ameliorated DD in diabetic db/db mice by reducing HR. Herein, we attempted to determine whether ivabradine has antifibrotic and cardioprotective effects in diabetic mice by directly suppressing CF proliferation and activation, independent of a reduction in HR. We found that knockdown of c-Jun N-terminal kinase (JNK) or p38 mitogen-activated protein kinase (MAPK), or treatment with ivabradine, reduced JNK and p38 MAPK phosphorylation and the protein expression of proliferating cell nuclear antigen, collagen I, collagen III, tissue inhibitor of matrix metalloproteinase 2, and α-smooth muscle actin, accompanied with upregulation of matrix metalloproteinase 2 both in high glucose-treated neonatal rat CFs and left ventricular CFs isolated from db/db mice. However, zatebradine (a HR-lowering agent) did not have these effects in vitro or in vivo. In addition, cardiac fibrosis and DD were ameliorated in db/db mice that were intravenously administered lentiviruses carrying short hairpin RNAs targeting JNK and p38 MAPK or administered ivabradine. Taken together, these findings demonstrate that the ivabradine-induced amelioration of cardiac fibrosis, and DD in db/db mice may be at least in part attributable to the suppression of CF proliferation and activation, through the inhibition of JNK and p38 MAPK.

Effect of heart rate on hospital mortality in critically ill patients may be modified by age: a retrospective observational study from large database

BACKGROUND

Heart rate has been found associated with mortality in critically ill patients. However, whether the association differs between the elderly and non-elderly patients was unknown.

METHODS

We conducted a retrospective observational study of adult patients admitted to the intensive care unit (ICU) in the United States. Demographic, vital signs, laboratory tests, and interventions were extracted and compared between the elderly and non-elderly patients. The main exposure was heart rate, the proportion of time spent in heart rate (PTS-HR) was calculated. The primary outcome was hospital mortality. The multivariable logistic regression model was performed to assess the relationship between PTS-HR and hospital mortality, and interaction between PTS-HR and age categories was explored.

RESULTS

104,276 patients were included, of which 52,378 (50.2%) were elderly patients and 51,898 (49.8%) were non-elderly patients. The median age was 66 (IQR 54-76) years. After adjusting for confounders, PTS-HR < 60 beats per minute (bpm) (OR 0.972, 95% CI [0.945, 0.998], p = 0.031, P_interaction = 0.001) and 60-80 bpm (OR 0.925, 95% CI [0.912, 0.938], p < 0.001, P_interaction = 0.553) were associated with decreased risk of mortality; PTS-HR 80-100 bpm was associated with decreased mortality in the non-elderly patients (OR 0.955, 95% CI [0.941,0.975], p < 0.001) but was associated with increased mortality in the very elderly patients (OR 1.018, 95% CI [1.003,1.029], p = 0.017, P_interaction < 0.001). PTS-HR > 100 bpm (OR 1.093, 95% CI [1.081,1.105], p < 0.001, P_interaction = 0.004) was associated with increased mortality.

CONCLUSIONS

The effect of heart rate on hospital mortality differs between the elderly and non-elderly critically ill patients.

Risk Factors for Longitudinal Resting Heart Rate and Its Associations With Cardiovascular Outcomes in the DCCT/EDIC Study

OBJECTIVE

Individuals with diabetes have higher resting heart rate compared with those without, which may be predictive of long-term cardiovascular disease (CVD) risk. Using data from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study, we evaluated whether the beneficial effect of intensive versus conventional diabetes therapy on heart rate persisted, the factors mediating the differences in heart rate between treatment groups, and the effects of heart rate on future CVD risk.

RESEARCH DESIGN AND METHODS

Longitudinal changes in heart rate, from annual electrocardiograms over 22 years of EDIC follow-up, were evaluated in 1,402 participants with type 1 diabetes. Linear mixed models were used to assess the effect of DCCT treatment group on mean heart rate over time, and Cox proportional hazards models were used to estimate the effect of heart rate on CVD risk during DCCT/EDIC.

RESULTS

At DCCT closeout, 52% of participants were male and mean ± SD age was 33 ± 7 years, diabetes duration 12 ± 5 years, and HbA_1c 7.4 ± 1.2% (intensive) and 9.1 ± 1.6% (conventional). Through EDIC, participants in the intensive group had significantly lower heart rate in comparison with the conventional group. While significant group differences in heart rate were fully attenuated by DCCT/EDIC mean HbA_1c, higher heart rate predicted CVD and major adverse cardiovascular events independent of other risk factors.

CONCLUSIONS

After 22 years of follow-up, former intensive versus conventional therapy remained significantly associated with lower heart rate, consistent with the long-term beneficial effects of intensive therapy on CVD. DCCT treatment group effects on heart rate were explained by differences in DCCT/EDIC mean HbA_1c.

Heart Rate and Heart Rate Variability Changes Are Not Related to Future Cardiovascular Disease and Death in People With and Without Dysglycemia: A Downfall of Risk Markers? The Whitehall II Cohort Study

OBJECTIVE

Higher resting heart rate (rHR) and lower heart rate variability (HRV) are associated with increased risk of cardiovascular disease (CVD) and all-cause mortality in people with and without diabetes. It is unknown whether temporal changes in rHR and HRV may contribute to this risk. We investigated associations between 5-year changes in rHR and HRV and risk of future CVD and death, taking into account participants' baseline glycemic state.

RESEARCH DESIGN AND METHODS

In this prospective, population-based cohort study we investigated 4,611 CVD-free civil servants (mean [SD] age, 60 [5.9] years; 70% men). We measured rHR and/or six indices of HRV. Associations of 5-year change in 5-min rHR and HRV with fatal and nonfatal CVD and all-cause mortality or the composite of the two were assessed, with adjustments made for relevant confounders. Effect modification by glycemic state was tested.

RESULTS

At baseline, 63% of participants were normoglycemic, 29% had prediabetes, and 8% had diabetes. During a median (interquartile range) follow-up of 11.9 (11.4; 12.3) years, 298 participants (6.5%) experienced a CVD event and 279 (6.1%) died of non-CVD-related causes. We found no association between 5-year changes in rHR and HRV and future events. Only baseline rHR was associated with all-cause mortality. A 10 bpm-higher baseline HR level was associated with an 11.4% higher rate of all-cause mortality (95% CI 1.0-22.9%; P = 0.032). Glycemic state did not modify associations.

CONCLUSIONS

Changes in rHR and HRV and possibly also baseline values of these measures are not associated with future CVD or death in people with or without dysglycemia.

Minimum heart rate and mortality in critically ill myocardial infarction patients: an analysis of the MIMIC-III database

Background

Low minimum heart rate (MHR) is common in critically ill myocardial infarction (MI) patients. However, the association between MHR and the mortality of critically ill MI patients remains unclear.

Methods

In this retrospective cohort study, a total of 2,031 critically ill MI patients were enrolled from the Medical Information Mart for Intensive Care (MIMIC)-III database. Patients were divided into a low MHR group [MHR <60 beats per minute (bpm)] and a high MHR group (MHR ≥60 bpm). A Cox proportional hazard model was used to elucidate the association between these two groups and the mortality of MI patients. The association between mortality and MHR as a continuous variable was analyzed non-parametrically using restricted cubic splines. Sensitivity analyses were conducted to determine the impact of different admission heart rate, hypertension, atrial fibrillation, and vasopressor use on our results.

Results

MI patients in the low MHR group had higher 30-day and 1-year mortality than those in the high MHR group (20.59% vs. 10.91%, P<0.001 and 29.76% vs. 19.31%, P<0.001, respectively). After adjustment, the low MHR group was significantly correlated with 30-day mortality [hazard ratio, 1.779, 95% confidence interval (CI), 1.400-2.261, P<0.001] and 1-year mortality (hazard ratio, 1.537, 95% CI, 1.272-1.859, P<0.001). This correlation remained remarkable in patients with low or high admission heart rate, with or without hypertension, and with or without atrial fibrillation. An apparent L-curve relationship was observed between the 30-day mortality or 1-year mortality and MHR as a continuous variable.

Conclusions

MHR under 60 bpm may be associated with a higher risk for both 30-day and 1-year mortality in critically ill MI patients. These findings highlight the possibility of MHR as an early risk indicator and potential therapeutic target for mortality in critically ill MI patients, which warrants further investigation.

ESC working group on e-cardiology position paper: use of commercially available wearable technology for heart rate and activity tracking in primary and secondary cardiovascular prevention-in collaboration with the European Heart Rhythm Association, European Association of Preventive Cardiology, Association of Cardiovascular Nursing and Allied Professionals, Patient Forum, and the Digital Health Committee

Commercially available health technologies such as smartphones and smartwatches, activity trackers and eHealth applications, commonly referred to as wearables, are increasingly available and used both in the leisure and healthcare sector for pulse and fitness/activity tracking. The aim of the Position Paper is to identify specific barriers and knowledge gaps for the use of wearables, in particular for heart rate (HR) and activity tracking, in clinical cardiovascular healthcare to support their implementation into clinical care. The widespread use of HR and fitness tracking technologies provides unparalleled opportunities for capturing physiological information from large populations in the community, which has previously only been available in patient populations in the setting of healthcare provision. The availability of low-cost and high-volume physiological data from the community also provides unique challenges. While the number of patients meeting healthcare providers with data from wearables is rapidly growing, there are at present no clinical guidelines on how and when to use data from wearables in primary and secondary prevention. Technical aspects of HR tracking especially during activity need to be further validated. How to analyse, translate, and interpret large datasets of information into clinically applicable recommendations needs further consideration. While the current users of wearable technologies tend to be young, healthy and in the higher sociodemographic strata, wearables could potentially have a greater utility in the elderly and higher-risk population. Wearables may also provide a benefit through increased health awareness, democratization of health data and patient engagement. Use of continuous monitoring may provide opportunities for detection of risk factors and disease development earlier in the causal pathway, which may provide novel applications in both prevention and clinical research. However, wearables may also have potential adverse consequences due to unintended modification of behaviour, uncertain use and interpretation of large physiological data, a possible increase in social inequality due to differential access and technological literacy, challenges with regulatory bodies and privacy issues. In the present position paper, current applications as well as specific barriers and gaps in knowledge are identified and discussed in order to support the implementation of wearable technologies from gadget-ology into clinical cardiology.

Elevated heart rate and cardiovascular risk in hypertension

Epidemiological studies have shown that chronically elevated resting heart rate (HR) is significantly associated with organ damage, morbidity and mortality in a wide range of patients including hypertensive patients. Evidence is also available that an increased HR reflects sympathetic nervous system overdrive which is also known to adversely affect organ structure and function and to increase the risk of unfavourable outcomes in several diseases. The causal relationship between elevated HR, organ damage, and cardiovascular outcomes can thus be explained by its relationship with sympathetic cardiovascular influences although evidence of sympathetically-independent adverse effect of HR increases per se makes it more complex. Interventions that target HR by modulating the sympathetic nervous system have therefore a strong pathophysiological and clinical rationale. As most clinical guidelines now recommend the use of combination therapies in patients with hypertension, it might be desirable to consider as combination components drugs which lower HR, if HR is elevated such as, according to guideliines, when it is above 80 b/min.

Association of Cardiovascular Autonomic Neuropathy and Distal Symmetric Polyneuropathy with All-Cause Mortality: A Retrospective Cohort Study

BACKGROUND

People with diabetic cardiovascular autonomic neuropathy (CAN) have increased cardiovascular mortality. However, the association between distal symmetric polyneuropathy (DSPN) or CAN with all-cause mortality is much less investigated. Thus, we set out to examine the effect of CAN and DSPN on all-cause mortality in a well-phenotyped cohort.

METHODS

All diabetes cases (n = 1,347) from the catchment area of a secondary diabetes care centre who had medical examination including neuropathy assessment between 1997 and 2016 were followed up for all-cause mortality in the NHS Hungary reimbursement database until 2018. We investigated the association of CAN (Ewing tests) and DSPN (Neurometer) with all-cause mortality using Cox models stratified by diabetes type.

RESULTS

Altogether, n = 131/1,011 persons with type 1/type 2 diabetes were included. Of the participants, 53%/43% were male, mean age was 46 ± 12/64 ± 10 years, diabetes duration was 13 ± 10/7 ± 8 years, 42%/29% had CAN, and 39%/37% had DSPN. During the 9 ± 5/8 ± 5-year follow-up, n = 28/494 participants died. In fully adjusted models, participants with type 1 diabetes patients with versus without DSPN had an increased mortality (HR 2.99, 95% CI 1.4-8.63), while no association with CAN was observed. In type 2 diabetes, both DSPN and CAN independently increased mortality (HR 1.32, 95% CI: 1.07-1.64, and HR 1.44, 95% CI: 1.17-1.76).

CONCLUSIONS

Our results are compatible with an increased risk of mortality in people with type 1 diabetes and DSPN. Furthermore, we report a similarly strong association between DSPN and CAN and all-cause mortality in type 2 diabetes mellitus.

Characterizing Effects of Antidiabetic Drugs on Heart Rate, Systolic and Diastolic Blood Pressure

A model-based meta-analysis was performed with reported data from obese subjects and patients with type 2 diabetes (T2DM) to characterize the effects of dipeptidyl peptidase 4 (DPP4) inhibitors, gastric inhibitory polypeptides (GIPs), glucagon-like peptide-1 (GLP1), and dual GIP/GLP1 agonists, or a combination of these antidiabetic drugs (ADs) on heart rate (HR), diastolic blood pressure (DBP), and systolic blood pressure (SBP). A systematic literature search and review after the Cochrane method identified sources for investigational and approved ADs resulted in a comprehensive database with data from 178 clinical studies in obese subjects and patients with T2DM. Results indicated that there were AD class-dependent effects on HR and SBP, whereas no clear AD-related effects on DBP were found. All AD classes, except for DPP4 inhibitors, increased HR. The largest increase of 12 bpm was seen with GLP1 receptor agonists. All AD classes appeared to decrease SBP. DPP4 inhibitors were associated with a marginal decrease of ~ 1 mmHg, whereas GLP1 and GIP/GLP1 dual agonists exhibited the largest decrease of ~ 3 mmHg in SBP. AD-related effects were similar in obese subjects and patients with T2DM. In conclusion, there are clinically relevant AD-related effects on both HR and SBP, but not on DBP. DPP4 inhibitors are associated with the smallest (if at all) effects on HR and SBP, whereas GLP1 inhibitors exhibited the largest effects on these two cardiovascular end points. Additional studies are warranted to further investigate how AD-related SBP decreases combined with HR increases affect long-term cardiovascular mortality.

Coronary artery calcification, carotid intima-media thickness and cardiac dysfunction in young adults with type 2 diabetes mellitus

AIMS

Cardiovascular diseases (CVD) are the major causes of mortality in patients with type 2 diabetes mellitus (T2DM). There is paucity of information on prevalence of subclinical atherosclerosis and cardiac dysfunction in young adults with T2DM. This study aimed to assess the prevalence of subclinical atherosclerosis and cardiac dysfunction in young adults with T2DM, asymptomatic for CVD.

METHODS

Sixty-two patients with T2DM, age between 30 and 50 years were evaluated for coronary artery calcium (CAC) score, carotid intima-media thickness (CIMT) and flow-mediated dilatation (FMD) at the brachial artery. All were subjected to 2D-color Doppler echocardiography, electrocardiography and testing for serum N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hsCRP). The results were compared with those in 60 age, sex and BMI-matched healthy controls.

RESULTS

Prevalence of a positive CAC score was comparable among subjects with and without T2DM (14.5% vs 11.7%). Patients with T2DM had a significantly higher CIMT (0.54 ± 0.15 vs 0.49 ± 0.10 mm, p = 0.01), left ventricular (LV) mass (170 ± 36 vs 147 ± 23 g, p < 0.001), heart rate (83 ± 13 vs 74 ± 11, p < 0.001) and QTc interval (402 ± 20 vs 382 ± 21 ms, p < 0.001) compared to controls. FMD was lower in patients with T2DM compared to controls (9.1 ± 4.4% vs 10.7 ± 3.9%, p = 0.04). There was a higher prevalence of LV hypertrophy (37% vs 7%, p < 0.001) and diastolic dysfunction (7% vs 0) in patients with T2DM compared to controls. None of the participants had systolic dysfunction. Hypertension (42 vs 7%, p < 0.001) and metabolic syndrome (76 vs 35%, p < 0.001) were more prevalent in the patient group. In the multivariate analysis, age was the lone predictor of CIMT and FMD; while T2DM and male gender were the independent predictors of LV mass.

CONCLUSIONS

Young adults with T2DM, asymptomatic for CVD had a higher prevalence of CVD risk factors, LV hypertrophy and diastolic dysfunction. A higher CIMT and LV mass, and a lower FMD were noted in patients with T2DM. CAC score was comparable between the groups and thus may not be a useful tool for assessment of subclinical atherosclerosis in this cohort, where CIMT and FMD may be more appropriate.

Influence of an SGLT2 inhibitor, tofogliflozin, on the resting heart rate in relation to adipose tissue insulin resistance

AIMS

To examine the effects of a sodium-glucose co-transporter 2 (SGLT2) inhibitor, tofogliflozin, on resting heart rate by exploring baseline factors that independently influenced changes in the resting heart rate.

METHODS

Data on 419 participants in tofogliflozin phase 2/3 trials were analysed. Changes in resting heart rate from baseline to week 24 were analysed using an analysis of covariance (ANCOVA) model with groups (tofogliflozin/placebo) as a fixed effect and baseline values as covariates. The antilipolytic effect was evaluated as adipose tissue insulin resistance (Adipo-IR) and was calculated as the product of fasting insulin and free fatty acid. Multivariate analysis evaluated independent factors for changes in resting heart rate from baseline to week 24.

RESULTS

Of the participants, 58% were men, and mean age, HbA_1c , BMI and resting heart rate were 57.6 years, 65 mmol/mol (8.1%), 25.5 kg/m² and 66 bpm, respectively. At week 24, adjusted mean difference vs. placebo in the change from baseline was -2.3 bpm [95% confidence interval (CI) -4.6, -0.1] with tofogliflozin. Changes in resting heart rate were positively correlated with changes in Adipo-IR, whereas reductions in HbA_1c , body weight and blood pressure were similar independent of changes in resting heart among quartiles of resting heart rate change. On multivariate analysis, higher baseline resting heart rates and Adipo-IR values were significantly associated with greater reductions in resting heart rate.

CONCLUSIONS

Tofogliflozin corrected resting heart rate levels in accordance with baseline levels. Correction of high resting heart rates may be attributed to improved adipose tissue insulin resistance, leading to correction of hyperinsulinaemia.

Aberrant sinus node firing during β-adrenergic stimulation leads to cardiac arrhythmias in diabetic mice

AIM

Cardiovascular complications, including cardiac arrhythmias, result in high morbidity and mortality in patients with type-2 diabetes mellitus (T2DM). Clinical and experimental data suggest electrophysiological impairment of the natural pacemaker of the diabetic heart. The present study examined sinoatrial node (SAN) arrhythmias in a mouse model of T2DM and physiologically probed their underlying cause.

METHODS

Electrocardiograms were obtained from conscious diabetic db/db and lean control db/+ mice. In vivo SAN function was probed through pharmacological autonomic modulation with isoprenaline, atropine and carbachol. Blood pressure stability and heart rate variability (HRV) were evaluated. Intrinsic SAN function was evaluated through ex vivo imaging of spontaneous Ca²⁺ transients in isolated SAN preparations.

RESULTS

While lean control mice showed constant RR intervals during isoprenaline challenge, the diabetic mice experienced SAN arrhythmias with large RR fluctuations in a dose-dependent manner. These arrhythmias were completely abolished by atropine pre-treatment, while carbachol pretreatment significantly increased SAN arrhythmia frequency in the diabetic mice. Blood pressure and HRV were comparable in db/db and db/+ mice, suggesting that neither augmented baroreceptor feedback nor autonomic neuropathy is a likely arrhythmia mechanism. Cycle length response to isoprenaline was comparable in isolated SAN preparations from db/db and db/+ mice; however, Ca²⁺ spark frequency was significantly increased in db/db mice compared to db/+ at baseline and after isoprenaline.

CONCLUSION

Our results demonstrate a dysfunction of cardiac pacemaking in an animal model of T2DM upon challenge with a β-adrenergic agonist. Ex vivo, higher Ca²⁺ spark frequency is present in diabetic mice, which may be directly linked to in vivo arrhythmias.

Observational analyses from ADVANCE and ADVANCE-ON

AIMS

To explain, and document, the epidemiological work associated with the action in diabetes and vascular disease: preterax and diamicron-modified release controlled evaluation (ADVANCE) clinical trial.

MATERIALS AND METHODS

ADVANCE was designed as a randomized controlled multicentre factorial trial in high-risk patients with diabetes. The two interventions were blood pressure lowering medications versus placebo, and intensive glucose control versus standard glucose control. Following termination of the trial, an observational study of surviving participants, able to join, was mounted: the ADVANCE - observational study (ADVANCE-ON). Other epidemiological analyses that were undertaken treated the trial as a cohort study, including using biomarkers from the blood samples taken from ADVANCE subjects as risk exposures.

RESULTS

More than 50 publications have reported epidemiological results from ADVANCE. The main results from ADVANCE-ON suggested attenuated benefits of ADVANCE's blood pressure lowering treatment on all-cause and cardiovascular death, but no such long-term benefits for intensive glucose control, although this did give persistent benefit for end-stage renal disease. The other epidemiological studies found, amongst other things, strong effects of NT-terminal pro-B-type natriuretic peptide and high-sensitivity cardiac troponin T on macrovascular events, microvascular events and all-cause death.

CONCLUSIONS

Embedding post-randomization and epidemiological analyses into clinical trials is worthwhile and can be highly productive in advancing scientific knowledge.

Resting Heart Rate and In-Hospital Mortality in Acute Ischemic Stroke Patients With and Without Atrial Fibrillation

BACKGROUND

The prognostic role of resting heart rate (RHR) on mortality in acute ischemic stroke (AIS) patients including atrial fibrillation (AF) is unclear. This study evaluated the relationship between RHR and in-hospital mortality among all AIS patients with and without AF.Methods and Results:The study enrolled 3,447 AIS patients from December 2013 to May 2014 across 22 hospitals in Suzhou City. Patients were divided into 2 groups based on median baseline RHR (<76 and ≥76 beats/min). Cox proportional hazard regression models were used to estimate the effects of RHR on all-cause in-hospital mortality. During hospitalization, 124 patients (3.6%) died from all causes. A multivariable model adjusted for potential covariates showed that higher RHR (≥76 beats/min) was associated with an increase in the risk of in-hospital mortality among AIS patients (hazard ratio [HR] 1.63; 95% confidence interval [CI] 1.09-2.45; P=0.018). This relationship was consistent in a subgroup analysis of patients without AF (HR 2.39; 95% CI 1.29-4.45; P=0.006). However, there was no significant association between higher RHR and in-hospital mortality among patients with AF (P=0.654). Similar findings were confirmed in analyses with heart rate as a continuous variable.

CONCLUSIONS

Higher RHR at admission was independently associated with in-hospital mortality in AIS patients without AF.

Association of pulse rate with outcomes in heart failure with reduced ejection fraction: a retrospective cohort study

BACKGROUND

In a real-world setting, the effect of pulse rate measured at the time of diagnosis and serially during follow-up and management, on outcomes in heart failure with reduced ejection fraction (HFrEF), has not been well-studied. Furthermore, how beta-blockade use in a real-world situation modifies this relation between pulse rate and outcomes in HFrEF is not well-known. Hence, we identified a large, national, real-world cohort of HFrEF to examine the association of pulse rate and outcomes.

METHODS

Using Veterans Affairs (VA) national electronic health records we identified incident HFrEF cases between 2006 and 2012. We examined the associations of both baseline and serially measured pulse rates, with mortality and days hospitalized per year for heart failure and for any cause, using crude and multivariable Cox proportional hazards and Poisson or negative binomial models, respectively. The exposure was examined as continuous, dichotomous, and categorical. Post-hoc analyses addressed the interaction of pulse rate and beta-blocker target dose.

RESULTS

We identified 51,194 incident HFrEF cases (67 ± 12 years, 98% male, 77% white. A significant positive, near linear relationship was observed for both baseline and serially measured pulse rates with all-cause mortality, all-cause hospitalization and heart failure hospitalization after adjusting for covariates including beta-blocker use. Patients who had a pulse rate ≥ 70 bpm in the past 6 months had 36% (95% CI: 31-42%), 25% (95% CI: 19-32%), and 51% (95% CI: 33-72%) increased rates of mortality, all-cause hospitalization, and heart failure hospitalization, respectively, compared to patients with pulse rates < 70 bpm. A minority of subjects (15%) were treated with guideline directed beta blockade ≥50% of recommended target dose, among whom better outcomes were seen compared to those who did not achieve target dose in patients with pulse rates both above and below 70 beats per minute.

CONCLUSIONS

High pulse rate, both at the time of diagnosis and during follow-up, is strongly associated with increased risk of adverse outcomes in HFrEF patients, independent of the use of beta-blockers. In a real-world setting, the majority of HFrEF patients do not achieve target dose of beta-blockade; greater use of strategies to reduce heart rate may improve outcomes in HFrEF.

Arterial Stiffness Modulates the Association of Resting Heart Rate With Rapid Renal Function Decline in Individuals With Type 2 Diabetes Mellitus

Objective:

Resting heart rate (RHR) has been associated with cardiovascular risk, but data on renal outcomes are still scarce. We aimed to study the association of RHR with rapid renal function decline (RRFD) and to explore whether the association of RHR with RRFD is modulated by arterial stiffness in individuals with type 2 diabetes mellitus.

Approach and Results:

One thousand one hundred forty-two Asian people with type 2 diabetes mellitus were followed for 3.9±0.9 years in a regional hospital and a primary care facility. RRFD was defined as eGFR decline of 5 mL/min per 1.73 m2 or greater per year. Arterial stiffness was assessed by carotid-femoral pulse wave velocity. One hundred sixty-eight participants (15%) were classified as having RRFD. Participants with elevated RHR were younger, had higher levels of HbA1c, albuminuria, C-reactive protein, and pulse wave velocity. Compared with the lowest quartile, participants in quartile 4 had a higher risk for RRFD after adjustment for known risk factors (adjusted odds ratio 1.91 [1.11–3.28]). RHR improved discrimination and net reclassification for prediction of RRFD above traditional risk factors. Remarkably, arterial stiffness modulated the association of RHR with RRFD ( P for interaction =0.03). RHR was significantly associated with risk of RRFD only in those with increased arterial stiffness (pulse wave velocity above age-reference value 7.7 m/s).

Conclusions:

RHR independently predicts RRFD, and the association is modulated by arterial stiffness. An elevated heart rate may be one factor in the spectrum of cardiovascular risk factors associated with renal functional impairment, especially in those with type 2 diabetes mellitus and an increased arterial stiffness.

Relationship of the Aggregation of Cardiovascular Risk Factors in the Parasympathetic Modulation of Young People with Type 1 Diabetes

Background and objectives: In healthy individuals, autonomic alterations are associated with the aggregation of cardiovascular risk factors. However, in individuals with type 1 diabetes, who are known to present autonomic alterations, mainly characterized by a reduction in parasympathetic modulation, these associations have not yet been investigated. We assess whether the aggregation of cardiovascular risk factors influences parasympathetic indices of heart rate variability in young people with type 1 diabetes. Materials and methods: This cross-sectional study included 39 individuals with type 1 diabetes (22.54 ± 4.31), evaluated in relation to the risk factors: blood pressure, fat percentage, and resting heart rate. For heart rate variability analysis, heart rate was recorded beat-to-beat using a cardio frequency meter (PolarS810i) for 30 min with the volunteers in dorsal decubitus. The parasympathetic heart rate variability indices were calculated: rMSSD, pNN50, high frequency (HF) n.u (normalized units), SD1, 2LV, and 2ULV. Data collection was carried out in 2014 and analyzed in 2017. Results: Individuals with two aggregate risk factors present a reduction in the values of the indices that reflect parasympathetic autonomic modulation compared to individuals without the risk factors analyzed, regardless of sex and age. Conclusion: In young people with type 1 diabetes, the aggregation of cardiovascular risk factors is associated with parasympathetic autonomic impairment.

Cardiovascular Effects of Liraglutide

BACKGROUND

Liraglutide is a glucagon-like 1 (GLP-1) agonist approved for treatment of type 2 diabetes and obesity.

OBJECTIVE

To review the cardiovascular effects of liraglutide including macrovascular and microvascular events, its use in heart failure, and its effects on heart rate and blood pressure.

RESULTS

The impact of liraglutide on cardiovascular outcomes was examined in a large welldesigned study published in 2016, the LEADER trial. This study included 9,340 patients with advanced type 2 diabetes and high baseline cardiovascular risk. The primary outcome was the first occurrence of death from cardiovascular causes, non-fatal myocardial infarction, or non-fatal stroke. After a median follow-up of 3.8 years, patients randomized to liraglutide had significant reduction in the composite primary outcome compared to patients randomized to placebo, hazard ratio (HR) 0.87; 95% CI 0.78-0.97. Death from cardiovascular causes was significantly reduced with liraglutide therapy (HR, 0.78; 95% CI 0.66-0.93), as well as death from any cause (HR, 0.85; 95% CI 0.74-0.97). In 2017, the LEADER investigators reported that nephropathy events were significantly lower after liraglutide therapy than placebo (HR 0.78; 95% CI 0.67-0.92), but there was no significant difference in retinopathy events. Meanwhile, other studies suggested that the use of liraglutide may be harmful in patients with severe heart failure, in part due to increase in heart rate.

CONCLUSION

Liraglutide is a useful therapy in patients with advanced type 2 diabetes complicated by cardiovascular disease, except patients with severe heart failure. Further studies are needed to evaluate the long-term effects of liraglutide, and to see whether its beneficial effects extend to patients with type 2 diabetes and low cardiac risk.

Resting heart rate and relation to disease and longevity: past, present and future

Assessment of heart rate has been used for millennia as a marker of health. Several studies have indicated that low resting heart rate (RHR) is associated with health and longevity, and conversely, a high resting heart to be associated with disease and adverse events. Longitudinal studies have shown a clear association between increase in heart rate over time and adverse events. RHR is a fundamental clinical characteristic and several trials have assessed the effectiveness of heart rate lowering medication, for instance beta-blockers and selective sinus node inhibition. Advances in technology have provided new insights into genetic factors related to RHR as well as insights into whether elevated RHR is a risk factor or risk marker. Recent animal research has suggested that heart rate lowering with sinus node inhibition is associated with increased lifespan. Furthermore, genome-wide association studies in the general population using Mendelian randomization have demonstrated a causal link between heart rate at rest and longevity. Furthermore, the development in personal digital devices such as mobile phones, fitness trackers and eHealth applications has made heart rate information and knowledge in this field as important as ever for the public as well as the clinicians. It should therefore be expected that clinicians and health care providers will be met by relevant questions and need of advice regarding heart rate information from patients and the public. The present review provides an overview of the current knowledge in the field of heart rate and health.

Update on the Impact, Diagnosis and Management of Cardiovascular Autonomic Neuropathy in Diabetes: What Is Defined, What Is New, and What Is Unmet

The burden of diabetic cardiovascular autonomic neuropathy (CAN) is expected to increase due to the diabetes epidemic and its early and widespread appearance. CAN has a definite prognostic role for mortality and cardiovascular morbidity. Putative mechanisms for this are tachycardia, QT interval prolongation, orthostatic hypotension, reverse dipping, and impaired heart rate variability, while emerging mechanisms like inflammation support the pervasiveness of autonomic dysfunction. Efforts to overcome CAN under-diagnosis are on the table: by promoting screening for symptoms and signs; by simplifying cardiovascular reflex tests; and by selecting the candidates for screening. CAN assessment allows for treatment of its manifestations, cardiovascular risk stratification, and tailoring therapeutic targets. Risk factors for CAN are mainly glycaemic control in type 1 diabetes mellitus (T1DM) and, in addition, hypertension, dyslipidaemia, and obesity in type 2 diabetes mellitus (T2DM), while preliminary data regard glycaemic variability, vitamin B12 and D changes, oxidative stress, inflammation, and genetic biomarkers. Glycaemic control prevents CAN in T1DM, whereas multifactorial intervention might be effective in T2DM. Lifestyle intervention improves autonomic function mostly in pre-diabetes. While there is no conclusive evidence for a disease-modifying therapy, treatment of CAN manifestations is available. The modulation of autonomic function by SGLT2i represents a promising research field with possible clinical relevance.

Comparison between newly diagnosed hypertension in diabetes and newly diagnosed diabetes in hypertension

BACKGROUND

Hypertension and diabetes mellitus are often jointly present, especially in early onset cases of either disease. We investigated clinical characteristics of hypertensive patients with newly diagnosed diabetes and diabetic patients with newly diagnosed hypertension.

METHODS

Our study subjects were recruited in a China nationwide multicenter registry of hypertension and diabetes (n = 2510). We performed logistic regression to compare patients seen for hypertension in cardiology, with newly diagnosed diabetes (n = 137) and patients seen for diabetes mellitus in endocrinology, with newly diagnosed hypertension (n = 155). Albuminuria was defined as a urinary albumin-to-creatinine ratio of ≥ 30 mg/g, and left ventricular hypertrophy according to the Cornell product index.

RESULTS

These two groups of patients with both hypertension and diabetes mellitus were similar in most of the characteristics (P ≥ 0.06). However, hypertensive patients with newly diagnosed diabetes, compared to diabetic patients with newly diagnosed hypertension, had a significantly greater body mass index (26.3 vs. 25.4 kg/m², P = 0.03) and slower heart rate (73.7 vs. 78.1 beats/min, P = 0.01). In logistic regression analyses adjusted for sex (48.3% women) and age (mean 60.0 ± 11.5 years), the odds ratio for newly diagnosed diabetes mellitus versus newly diagnosed hypertension was 1.27 (95% CI 1.03-1.56) and 0.80 (95% CI 0.66-0.96) for body mass index (+ 3 kg/m²) and heart rate (+ 10 beat/min), respectively. Hypertensive patients with newly diagnosed diabetes also had a lower prevalence of albuminuria (16.0% vs. 30.1%, P = 0.02) and slightly and non-significantly higher prevalence of left ventricular hypertrophy (5.1% vs. 1.9%, P = 0.14) than diabetic patients with newly diagnosed hypertension.

CONCLUSIONS

Earlier or later onset of hypertension than diabetes mellitus may have different risk factors and organ damage.

Prevalence and factors associated with fast resting heart rate in hypertensive and normotensive patients

Background: Fast resting heart rate (RHR) is easily neglected in clinical practice of hypertension treatment.Aims: We aimed to investigate the prevalence of fast RHR and associated factors in hypertensive and normotensive individuals.Methods: We retrospectively analyzed data from two cross-sectional studies conducted in China. A total of 6763 hypertensive patients and 2807 age and sex-matched normotensive subjects with complete data on resting electrocardiogram and medical history were included. Fast RHR was defined as RHR > 85 bpm.Results: The prevalence of fast RHR was higher in hypertensive patients as compared with the normotensives (14.4% vs 7.1%, P < 0.01). In both hypertensive and normotensive subjects, fast RHR appeared as a "U-type" distribution as aging and a "inverted J type" trend as body mass index (BMI) increasing. Multivariate regression analysis showed that fast RHR was associated with age >65 or <25 years old (OR = 1.32, 95% CI 1.08-1.61), BMI <18.5 kg/m² (OR = 2.94, 95%CI 1.47-5.87) and hypercholesterolemia (OR = 1.30, 95%CI 1.10-1.53) in hypertensive patients. Fast RHR in the normotensives was associated with female (OR = 1.78, 95%CI 1.27-2.48), pre-hypertensive state (OR = 2.38, 95%CI 1.61-3.52), and rural area origin (OR = 1.50, 95%CI 1.01-2.42). Stroke and diabetes conferred closer relevance to fast RHR in both hypertensive (OR = 1.31, 95%CI 1.02-1.69 and OR 2.26, 95%CI 1.60-3.21) and normotensive individuals (OR = 2.67, 95%CI 1.36-5.21 and OR = 2.77, 95%CI 1.47-5.23).Conclusion: Fast RHR might be common in patients with hypertension. Prior stroke and diabetes history is common associated with fast RHR. Other factors associated with fast RHR seem to be different between hypertensive patients and normotensive subjects.Abbreviations: BMI: body mass index; CI: Confidence Interval; DBP: diastolic blood pressure; ECG: electrocardiogram; OR: odd ratio; RHR: resting heart rate; SBP: systolic blood pressure.

Silencing of NOD2 protects against diabetic cardiomyopathy in a murine diabetes model

The aim of the present study was to investigate the role of the nucleotide‑binding oligomerization domain (NOD) 2 in high glucose (HG)‑induced myocardial apoptosis and fibrosis in mice. Mouse models of diabetes were induced by streptozotocin (STZ). NOD2 expression was knocked down by injection of lentivirus‑mediated short‑hairpin RNA. Alternatively, small interfering RNA‑NOD2 was transfected into cardiomyocytes and cardiac fibroblasts (CFs). A hemodynamic assay was used to assess the cardiac function in the mouse model. Hematoxylin and eosin, Masson and terminal deoxynucleotidyl transferase dUTP nick end labeling staining was performed to observe pathological changes and injury of myocardial tissue. The expression levels of NOD2, collagen I and III, and transforming growth factor‑β (TGF‑β) and apoptotic proteins were quantified by reverse transcription‑quantitative polymerase chain reaction and western blotting. NOD2 silencing ameliorated diabetes‑induced myocardial apoptosis and fibrosis in mice. NOD2, collagen I, collagen III, TGF‑β and pro‑apoptotic proteins were upregulated in the diabetic cardiomyopathy (DCM) model group, but interference of NOD2 suppressed these alterations in protein expression levels. NOD2 is upregulated in HG‑induced primary cardiomyocytes and CFs. Suppression of NOD2 attenuated HG‑induced cardiomyocyte apoptosis and proliferation of CFs. Overall, NOD2 silencing alleviated myocardial apoptosis and fibrosis in diabetic mice. The results of the present study demonstrated an understanding of the role of NOD2 in diabetes‑induced cardiomyopathy, which provides a novel target and therapies for the prevention and treatment of DCM.

Identifying Risk Factors for Drug Use in an Iranian Treatment Sample: A Prediction Approach Using Decision Trees

INTRODUCTION AND AIM

Substance abuse exacts considerable social and health care burdens throughout the world. The aim of this study was to create a prediction model to better identify risk factors for drug use.

DESIGN AND METHODS

A prospective cross-sectional study was conducted in South Khorasan Province, Iran. Of the total of 678 eligible subjects, 70% (n: 474) were randomly selected to provide a training set for constructing decision tree and multiple logistic regression (MLR) models. The remaining 30% (n: 204) were employed in a holdout sample to test the performance of the decision tree and MLR models. Predictive performance of different models was analyzed by the receiver operating characteristic (ROC) curve using the testing set. Independent variables were selected from demographic characteristics and history of drug use.

RESULTS

For the decision tree model, the sensitivity and specificity for identifying people at risk for drug abuse were 66% and 75%, respectively, while the MLR model was somewhat less effective at 60% and 73%. Key independent variables in the analyses included first substance experience, age at first drug use, age, place of residence, history of cigarette use, and occupational and marital status.

DISCUSSION AND CONCLUSION

While study findings are exploratory and lack generalizability they do suggest that the decision tree model holds promise as an effective classification approach for identifying risk factors for drug use. Convergent with prior research in Western contexts is that age of drug use initiation was a critical factor predicting a substance use disorder.

Resting Heart Rate Is Not Associated with Cognitive Function

AIMS

In order to examine the hypothesis that elevated resting heart rate (RHR) is associated with impaired cognitive score, we investigated the relationship between RHR and cognitive score in middle-aged, elderly and old Danish subjects from the general population.

METHODS

Composite cognitive scores derived from the result of 5 age-sensitive cognitive tests for a total of 7,002 individuals (Middle-aged Danish twin: n = 4,132, elderly Danish twins: n = 2,104 and Danish nonagenarian: n = 766) divided according to RHR and compared using linear regression models adjusted for sex, age, previous heart conditions and hypertension. RHR was assessed by palpating radial pulse. Genetic and shared environmental confounding was addressed in intrapair analyses of 2,049 twin pairs.

RESULTS

In unadjusted multivariate models and in multivariable models adjusting for age, sex, heart conditions and hypertension, RHR was not associated with cognitive function. Furthermore, the intrapair analyses showed that RHR was not associated with cognitive score testing within twin pairs, as measured by the proportion of twin pairs in which the twin with higher RHR also was the twin with the lowest composite cognitive score (1,049 pairs of 2,049 pairs [51% (95% CI 49-53), p < 0.289]).

CONCLUSION

While elevated RHR has been shown to be associated with adverse health events and poor fitness level, RHR has no relation to cognitive function in the general population.

Caloric Restriction and Its Effect on Blood Pressure, Heart Rate Variability and Arterial Stiffness and Dilatation: A Review of the Evidence

Essential hypertension, fast heart rate, low heart rate variability, sympathetic nervous system dominance over parasympathetic, arterial stiffness, endothelial dysfunction and poor flow-mediated arterial dilatation are all associated with cardiovascular mortality and morbidity. This review of randomised controlled trials and other studies demonstrates that caloric restriction (CR) is capable of significantly improving all these parameters, normalising blood pressure (BP) and allowing patients to discontinue antihypertensive medication, while never becoming hypotensive. CR appears to be effective regardless of age, gender, ethnicity, weight, body mass index (BMI) or a diagnosis of metabolic syndrome or type 2 diabetes, but the greatest benefit is usually observed in the sickest subjects and BP may continue to improve during the refeeding period. Exercise enhances the effects of CR only in hypertensive subjects. There is as yet no consensus on the mechanism of effect of CR and it may be multifactorial. Several studies have suggested that improvement in BP is related to improvement in insulin sensitivity, as well as increased nitric oxide production through improved endothelial function. In addition, CR is known to induce SIRT1, a nutrient sensor, which is linked to a number of beneficial effects in the body.

A comparative safety review between GLP-1 receptor agonists and SGLT2 inhibitors for diabetes treatment

INTRODUCTION

Glucagon-like peptide-1 receptor agonists (GLP-1RA) and sodium glucose cotransporter 2 inhibitors (SGLT2i) are of particular interest in type 2 diabetes treatment strategies, due to their efficacy in reducing HbA1c with a low risk of hypoglycaemia, to their positive effects on body weight and blood pressure and in light of their effects on cardiovascular risk and on nephroprotection emerged from the most recent cardiovascular outcome trials. Since it is therefore very likely that GLP-1RA and SGLT2i use will become more and more common, it is more and more important to gather and discuss information about their safety profile.

AREAS COVERED

Adverse events and the safety concerns most often emerged in trials with GLP-1RA namely, exenatide long acting release (LAR), dulaglutide, liraglutide, semaglutide, lixisenatide or SGLT2i, namely empagliflozin, dapagliflozin, canagliflozin and SGLT2i with an attempt at comparing the safety profiles of molecules of these two classes.

EXPERT OPINION

GLP-1RA and SGLT2i, although each associated with different specific side effects, share a 'similar' safety profile and are both drugs relatively easy to handle. The potentially complementary mechanisms of action, the cardio and nephroprotective effects demonstrated by molecules of both classes, make these drugs potentially useful even in add on to each other.

Heart rate is an independent predictor of all-cause mortality in individuals with type 2 diabetes: The diabetes heart study

AIM

To assess the association of resting heart rate with all-cause and cardiovascular disease (CVD) mortality in the Diabetes Heart Study (DHS).

METHODS

Out of a total of 1443 participants recruited into the DHS, 1315 participants with type 2 diabetes who were free of atrial fibrillation and supraventricular tachycardia during the baseline exam were included in this analysis. Heart rate was collected from baseline resting electrocardiogram and mortality (all-cause and CVD) was obtained from state and national death registry. Kaplan-Meier (K-M) and Cox proportional hazard analyses were used to assess the association.

RESULTS

The mean age, body mass index (BMI) and systolic blood pressure (SBP) of the cohort were 61.4 ± 9.2 years, 32.0 ± 6.6 kg/m², and 139.4 ± 19.4 mmHg respectively. Fifty-six percent were females, 85% were whites, 15% were blacks, 18% were smokers. The mean ± SD heart rate was 69.8 (11.9) beats per minute (bpm). After a median follow-up time of 8.5 years (maximum follow-up time is 14.0 years), 258 participants were deceased. In K-M analysis, participants with heart rate above the median had a significantly higher event rate compared with those below the median (log-rank P = 0.0223). A one standard deviation increase in heart rate was associated with all-cause mortality in unadjusted (hazard ratio 1.16, 95%CI: 1.03-1.31) and adjusted (hazard ratio 1.20, 95%CI: 1.05-1.37) models. Similar results were obtained with CVD mortality as the outcome of interest.

CONCLUSION

Heart rate is an independent predictor of all-cause mortality in this population with type 2 diabetes. In this study, a 1-SD increase in heart rate was associated with a 20% increase in risk suggesting that additional prognostic information may be gleaned from this ubiquitously collected vital sign.

A review of glucagon-like peptide-1 receptor agonists and their effects on lowering postprandial plasma glucose and cardiovascular outcomes in the treatment of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is an independent risk factor for cardiovascular (CV) comorbidities, with CV disease being the most common cause of death in adults with T2DM. Although glucocentric therapies may improve glycaemic control (as determined by glycated haemoglobin levels), evidence suggests that this approach alone has limited beneficial effects on CV outcomes relative to improvements in lipid and blood pressure control. This may be explained in part by the fact that current antidiabetic treatment regimens primarily address overall glycaemia and/or fasting plasma glucose, but not the postprandial plasma glucose (PPG) excursions that have a fundamental causative role in increasing CV risk. This literature review evaluates the relationship between PPG and the risk of CV disease, discusses the treatment of T2DM with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and examines the associated CV outcomes. The literature analysis suggests that exaggerated PPG excursions are a risk factor for CV disease because of their adverse pathophysiologic effects on the vasculature, resulting in increased all-cause and CV-related mortality. Although GLP-1 RAs are well established in the current T2DM treatment paradigm, a subgroup of these compounds has a particularly pronounced, persistent and short-lived effect on gastric emptying and, hence, lower PPG substantially. However, current long-term data on CV outcomes with GLP-1 RAs are contradictory, with both beneficial and adverse effects having been reported. This review explores the opportunity to direct treatment towards controlling PPG excursions, thereby improving not only overall glycaemic control but also CV outcomes.