Glycemic Control in Type 1 Diabetes and Long-Term Risk of Cardiovascular Events or Death After Coronary Artery Bypass Grafting

RBP4-based Multimarker Score: A Prognostic Tool for Adverse Cardiovascular Events in Acute Coronary Syndrome Patients

CONTEXT

Retinol binding protein 4 (RBP4) has been implicated in the progression of cardiovascular diseases. However, its association with major adverse cardiovascular events (MACEs) in patients with acute coronary syndrome (ACS) remains obscure.

OBJECTIVE

Here, we examined the prognostic value of baseline RBP4 and its derived multimarker score for MACEs in ACS patients.

METHODS

A total of 826 patients with ACS were consecutively recruited from the department of cardiology and prospectively followed up for a median of 1.95 years (interquartile range, 1.02-3.25 years). Plasma RBP4 was measured using enzyme-linked immunosorbent assay. Adjusted associations between RBP4 and its derived multimarker score (1 point was assigned when RBP4 ≥ 38.18μg/mL, left ventricular ejection fraction [LVEF] ≤ 55%, N-terminal pro-B-type natriuretic peptide [NT-proBNP] ≥ 450 ng/L, estimated glomerular filtration rate [eGFR] ≤ 90 mL/min/1.73 m2, and age ≥60) with MACEs were analyzed.

RESULTS

In total, 269 ACS patients (32.57%) experienced MACEs. When patients were grouped by multimarker score (0-1, n = 315; 2-3, n = 406; 4-5, n = 105), there was a significant graded association between RBP4-based multimarker score and risk of MACEs (intermediate score (2-3): HRadj: 1.80; 95% CI, 1.34-2.41; high score (4-5): HRadj: 3.26; 95% CI, 2.21-4.81) and its components (P < .05 for each). Moreover, the prognostic and discriminative value of the RBP4-derived multimarker score remained robust in ACS patients with various high-risk anatomical or clinical characteristics.

CONCLUSION

The RBP4-derived 5-item score serves as a useful risk stratification and decision support for secondary prevention in patients with ACS.

Hyperlipidemia and Cardiovascular Disease in People with Type 1 Diabetes: Review of Current Guidelines and Evidence

PURPOSE OF REVIEW

In this review, we discuss the prevalence of cardiovascular disease in people with type 1 diabetes. We outline key risk factors associated with increased cardiovascular event rates and discuss the prevalence and mechanisms underlying hyperlipidemia in people with type 1 diabetes. Finally, we summarize the evidence to support early and more aggressive lipid-lowering therapy in people with type 1 diabetes and review current guideline recommendations.

RECENT FINDINGS

Comprehensive treatment of hyperglycemia, hypertension, and hyperlipidemia reduces adverse cardiovascular outcomes in people with type 2 diabetes. In contrast, evidence to support a comparable benefit of intensive cardiovascular risk factor management in people with type 1 diabetes is lacking from prospective, randomized trials and has only been shown in registries. Therefore, current treatment guidelines extrapolate prospective clinical trial evidence obtained in people with type 2 diabetes to provide similar treatment recommendations for people with type 1 and type 2 diabetes. Evidence supports the more aggressive treatment of cardiovascular risk factors in people with type 1 diabetes, who would likely benefit from early risk stratification and comprehensive risk factor management, including aggressive lipid-lowering therapy.

Long-term cardiovascular prognosis of patients with type 1 diabetes after myocardial infarction

Background

To explore long-term cardiovascular prognosis after myocardial infarction (MI) among patients with type 1 diabetes.

Methods

Patients with type 1 diabetes surviving 90 days after MI (n = 1508; 60% male, mean age = 62.1 years) or without any type of diabetes (n = 62,785) in Finland during 2005–2018 were retrospectively studied using multiple national registries. The primary outcome of interest was a combined major adverse cardiovascular event (MACE; cardiovascular death, recurrent MI, ischemic stroke, or heart failure hospitalization) studied with a competing risk Fine-Gray analyses. Median follow-up was 3.9 years (maximum 12 years). Differences between groups were balanced by multivariable adjustments and propensity score matching (n = 1401 patient pairs).

Results

Cumulative incidence of MACE after MI was higher in patients with type 1 diabetes (67.6%) compared to propensity score-matched patients without diabetes (46.0%) (sub-distribution hazard ratio [sHR]: 1.94; 95% confidence interval [CI]: 1.74–2.17; p < 0.0001). Probabilities of cardiovascular death (sHR 1.81; p < 0.0001), recurrent MI (sHR 1.91; p < 0.0001), ischemic stroke (sHR 1.50; p = 0.0003), and heart failure hospitalization (sHR 1.98; p < 0.0001) were higher in patients with type 1 diabetes. Incidence of MACE was higher in diabetes patients than in controls in subgroups of men and women, patients aged < 60 and ≥ 60 years, revascularized and non-revascularized patients, and patients with and without atrial fibrillation, heart failure, or malignancy.

Conclusions

Patients with type 1 diabetes have notably poorer long-term cardiovascular prognosis after an MI compared to patients without diabetes. These results underline the importance of effective secondary prevention after MI in patients with type 1 diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01608-3.

Management of Hyperglycemia in Hospitalized Adult Patients in Non-Critical Care Settings: An Endocrine Society Clinical Practice Guideline

BACKGROUND

Adult patients with diabetes or newly recognized hyperglycemia account for over 30% of noncritically ill hospitalized patients. These patients are at increased risk for adverse clinical outcomes in the absence of defined approaches to glycemic management.

OBJECTIVE

To review and update the 2012 Management of Hyperglycemia in Hospitalized Patients in Non-Critical Care Settings: An Endocrine Society Clinical Practice Guideline and to address emerging areas specific to the target population of noncritically ill hospitalized patients with diabetes or newly recognized or stress-induced hyperglycemia.

METHODS

A multidisciplinary panel of clinician experts, together with a patient representative and experts in systematic reviews and guideline development, identified and prioritized 10 clinical questions related to inpatient management of patients with diabetes and/or hyperglycemia. The systematic reviews queried electronic databases for studies relevant to the selected questions. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess the certainty of evidence and make recommendations.

RESULTS

The panel agreed on 10 frequently encountered areas specific to glycemic management in the hospital for which 15 recommendations were made. The guideline includes conditional recommendations for hospital use of emerging diabetes technologies including continuous glucose monitoring and insulin pump therapy; insulin regimens for prandial insulin dosing, glucocorticoid, and enteral nutrition-associated hyperglycemia; and use of noninsulin therapies. Recommendations were also made for issues relating to preoperative glycemic measures, appropriate use of correctional insulin, and diabetes self-management education in the hospital. A conditional recommendation was made against preoperative use of caloric beverages in patients with diabetes.

CONCLUSION

The recommendations are based on the consideration of important outcomes, practicality, feasibility, and patient values and preferences. These recommendations can be used to inform system improvement and clinical practice for this frequently encountered inpatient population.

A Systematic Review Supporting the Endocrine Society Clinical Practice Guideline for the Management of Hyperglycemia in Adults Hospitalized for Noncritical Illness or Undergoing Elective Surgical Procedures

CONTEXT

Individuals with diabetes or newly recognized hyperglycemia account for over 30% of noncritically ill hospitalized patients. Management of hyperglycemia in these patients is challenging.

OBJECTIVE

To support development of the Endocrine Society Clinical Practice Guideline for management of hyperglycemia in adults hospitalized for noncritical illness or undergoing elective surgical procedures.

METHODS

We searched several databases for studies addressing 10 questions provided by a guideline panel from the Endocrine Society. Meta-analysis was conducted when feasible. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess certainty of evidence.

RESULTS

We included 94 studies reporting on 135 553 patients. Compared with capillary blood glucose, continuous glucose monitoring increased the number of patients identified with hypoglycemia and decreased mean daily blood glucose (BG) (very low certainty). Data on continuation of insulin pump therapy in hospitalized adults were sparse. In hospitalized patients receiving glucocorticoids, combination neutral protamine hagedorn (NPH) and basal-bolus insulin was associated with lower mean BG compared to basal-bolus insulin alone (very low certainty). Data on NPH insulin vs basal-bolus insulin in hospitalized adults receiving enteral nutrition were inconclusive. Inpatient diabetes education was associated with lower HbA1c at 3 and 6 months after discharge (moderate certainty) and reduced hospital readmissions (very low certainty). Preoperative HbA1c level < 7% was associated with shorter length of stay, lower postoperative BG and a lower number of neurological complications and infections, but a higher number of reoperations (very low certainty). Treatment with glucagon-like peptide-1 agonists or dipeptidyl peptidase-4 inhibitors in hospitalized patients with type 2 diabetes and mild hyperglycemia was associated with lower frequency of hypoglycemic events than insulin therapy (low certainty). Caloric oral fluids before surgery in adults with diabetes undergoing surgical procedures did not affect outcomes (very low certainty). Counting carbohydrates for prandial insulin dosing did not affect outcomes (very low certainty). Compared with scheduled insulin (basal-bolus or basal insulin + correctional insulin), correctional insulin was associated with higher mean daily BG and fewer hypoglycemic events (low certainty).

CONCLUSION

The certainty of evidence supporting many hyperglycemia management decisions is low, emphasizing importance of shared decision-making and consideration of other decisional factors.

Case Fatality of Patients With Type 1 Diabetes After Myocardial Infarction

OBJECTIVE

Type 1 diabetes is a risk factor for myocardial infarction (MI). We aimed to evaluate the case fatality in patients with type 1 diabetes after MI.

RESEARCH DESIGN AND METHODS

Consecutive patients experiencing MI with type 1 diabetes (n = 1,935; 41% female; mean age 62.5 years) and without diabetes (n = 74,671) admitted to 20 hospitals in Finland from 2005 to 2018 were studied using national registries. The outcome of interest was death within 1 year after MI. Differences between groups were balanced by multivariable adjustments and propensity score matching.

RESULTS

Case fatality was higher in patients with type 1 diabetes than in propensity score-matched controls without diabetes at 30 days (12.8% vs. 8.5%) and at 1 year (24.3% vs. 16.8%) after MI (hazard ratio 1.55; 95% CI 1.32-1.81; P < 0.0001). Patients with type 1 diabetes had poorer prognosis in subgroups of men and women and of those with and without ST-elevation MI, with and without revascularization, with and without atrial fibrillation, and with and without heart failure. The relative fatality risk in type 1 diabetes was highest in younger patients. Older age, heart failure, peripheral vascular disease, renal failure, and no revascularization were associated with worse prognosis after MI. The case fatality among patients with type 1 diabetes decreased during the study period, but outcome differences compared with patients without diabetes remained similar.

CONCLUSIONS

Patients with type 1 diabetes are at higher risk of death after MI than patients without diabetes. Our findings call for attention to vigorous cardiovascular disease prevention in patients with type 1 diabetes.

Influence of Baseline HbA1c and Antiplatelet Therapy on 1-Year Vein Graft Outcome

BACKGROUND

The influence of baseline HbA1c levels on vein graft outcomes post coronary artery bypass grafting (CABG) remains unclear.

OBJECTIVE

The purpose of this study was to assess the association between baseline HbA1c and 1-year vein graft patency, and the effects of antiplatelet therapy on the 1-year vein graft patency after CABG in patients with baseline HbA1c <6.5% vs ≥6.5%.

METHODS

We examined the subgroups with baseline HbA1c <6.5% vs ≥6.5% from the DACAB trial (NCT02201771), in which 500 patients were randomly allocated to receive ticagrelor plus aspirin (T+A), ticagrelor alone (T), or aspirin alone (A) for 1 year after CABG. The primary outcome was the vein graft patency (FitzGibbon grade A) at 1 year.

RESULTS

A total of 405 patients with available baseline HbA1c data were included in this subgroup analysis. Of them, there were 233 patients (678 vein grafts) with baseline HbA1c <6.5% and 172 patients (512 vein grafts) with baseline HbA1c ≥6.5%. Compared with the HbA1c <6.5% subgroup, the HbA1c ≥6.5% subgroup showed worse 1-year vein graft patency (adjusted odds ratio [OR] for nonpatency: 1.69, 95% confidence interval [CI]: 1.08-2.64). T+A showed higher vein graft patency than A in both HbA1c <6.5% (adjusted OR for nonpatency: 0.34, 95% CI: 0.15-0.75) and HbA1c ≥6.5% subgroups (adjusted OR for nonpatency: 0.45, 95% CI: 0.19-1.09), without an interaction effect (P for interaction = 0.335), whereas T did not show more significant improvement than A in both subgroups.

CONCLUSIONS

In the DACAB trial, lower baseline HbA1c was associated with higher vein graft patency 1 year after CABG. T+A improved 1-year vein graft patency vs A, irrespective of baseline HbA1c.

Glycemic Control in Coronary Artery Bypass Graft Surgery: A Different Perspective

Background

Hyperglycemia during coronary artery bypass graft surgery (CABG) strongly predicts intra- and post-operative adverse consequences.

Objectives

This study aimed to evaluate the quality of glycemic management during CABG in an academic center regarding peripheral blood and coronary sinus values.

Methods

This prospective descriptive study encompassed 55 eligible patients undergoing on-pump CABG surgery in 2020. Peripheral blood glucose (BG) was measured four times, before anesthesia induction (T0), before cardiopulmonary bypass pump (CPB) (T1), during CPB (T2), at the end of CPB (T3), and at the end of surgery (T4). The surgeon also took a sample of the coronary sinus BG.

Results

The BG variations from T0 to T4 were statistically significant (P < 0.0001). The higher values detected in the ASA class III compared to ASA classes II were statistically significant at T1 (P = 0.01) and T2 (P = 0.025): patients with the higher BMI showed the higher levels of BG. In this regard, the differences were significant at T0 (P = 0.0001), T2 (P = 0.004), and T3 (P = 0.015). Regarding coronary sinus, the mean BG was 222.18 ± 75.74 mg/dL. It was also observed that the ASA class III (P = 0.001), longer duration of CPB (P = 0.021), higher IV fluid volume administrated during surgery (P = 0.023), higher BMI (P = 0.0001), and less urine volume at the end of surgery (P = 0.049) were significantly associated with the higher BG of the coronary sinus.

Conclusions

The existing glycemic management protocols on the CABG patients were acceptable in our hospital. However, the BG level of the coronary sinus was higher than the peripheral one.

Impact of preoperative glycometabolic status on outcomes in cardiac surgery: Systematic review and meta-analysis

BACKGROUND

Historically, impaired glucose metabolism has been associated with early and late complicated clinical outcomes after cardiac surgery; however, such a condition is not specific to subjects with diabetes mellitus and involves a larger patient population.

METHODS

Databases were screened (January 2000 to December 2020) to identify eligible articles; studies that evaluated the association between preoperative metabolic status, as assessed by glycosylated hemoglobin levels and clinical outcomes, were considered. The studies were stratified in thresholds by baseline glycosylated hemoglobin level (lower vs higher).

RESULTS

Thirty studies, involving 34,650 patients, were included in the review. In a meta-analysis stratified by glycosylated hemoglobin levels, early mortality was numerically reduced in each threshold comparison and yielded the highest reductions when less than 5.5% versus greater than 5.5% glycosylated hemoglobin levels were compared (risk ratio, 0.39; 95% confidence interval, 0.18-0.84; P = .02). Comparing higher glycosylated hemoglobin threshold values yielded comparable results. Late mortality was reduced with lower levels of glycosylated hemoglobin. Low preoperative glycosylated hemoglobin was associated with the lowest risk of sternal wound infections (risk ratio, 0.50; 95% confidence interval, 0.32-0.80; P = .003 and risk ratio, 0.53; 95% confidence interval, 0.39-0.70; P < .0001) for comparisons of less than 7.5% versus greater than 7.5% and less than 7.0% versus greater than 7.0% glycosylated hemoglobin thresholds, respectively. Additionally, levels of glycosylated hemoglobin lower than 7% were associated with reduced hospital stay, lower risk of stroke/transient ischemic attack (risk ratio 0.53; 95% confidence interval, 0.39-0.70; P < .0001), and acute kidney injury (risk ratio, 0.65; 95% confidence interval, 0.54-0.79; P < .0001).

CONCLUSIONS

Lower levels of glycosylated hemoglobin in patients undergoing cardiac surgery are associated with a lower risk of early and late mortality, as well as in the incidence of postoperative acute kidney injury, neurologic complications, and wound infection, compared with higher levels.

The Effect of Glycemic Control on Cardiac Outcomes in Saudi Diabetic Patients who Underwent Coronary Angiogram

Background:

Diabetes mellitus is a metabolic disorder that causes impaired insulin secretion or cellular dysfunction. Glycated hemoglobin (HbA1c) indicates the long-term level of glucose. Diabetes can lead to cardiovascular complications such as acute coronary syndrome , which might require coronary intervention.

Objectives:

The aim of this study was to estimate the effect of glycemic control measured by HbA1c levels on cardiac complications in Saudi diabetic patients who underwent percutaneous coronary intervention (PCI) or Coronary artery bypass graft (CABG).

Methodology:

It was a cohort retrospective study conducted at King Abdulaziz Cardiac Center with a total sample size of 379 patients. The charts of all those diabetic patients were reviewed and their HbA1c level, type of intervention were compared to determine their effect on cardiac outcomes and complications. Inclusion criteria involved the age group 50–70 years within follow-up period of 3 years. Any patient known to have renal failure, liver dysfunction, type one diabetes, and cancer were excluded. The HbA1c level was divided into two groups (<7.5%, ≥7.5%).

Results:

Total sample size was 379, and the mean age was (60.33 ± 5.98) with male being (66.5%). HbA1c levels at admission were (mean 9.15 ± 2.03), whereas the mean after 3 years was (8.629 ± 1.518). The uncontrolled group was more likely to have PCI (n = 302), in comparison to the controlled group (n = 77) with a P value of 0.04. However, the controlled group was more likely to undergo medical treatment P value of 0.001. Patients with uncontrolled Hba1c after the intervention had a higher readmission rate with a P value of 0.018.

Conclusions:

Patients with an elevated level of HbA1c were more likely to be managed with PCI. Furthermore, they are at a higher risk of multiple readmissions. Patients who had CABG were at a lower risk of cardiac complications. Further studies are required in our population to consider different approaches of diabetes control for preventing adverse outcomes.

Coronary Artery Bypass Grafting vs Percutaneous Coronary Intervention in Patients With Diabetes

As percutaneous coronary intervention (PCI) continues to evolve, comparative outcomes for PCI vs coronary artery bypass grafting (CABG) remain relevant in diabetic patients. All revascularization procedures in patients with coronary artery disease and diabetes mellitus from 2010 to 2018 were included. Propensity matching was used to identify equivalent cohorts to compare revascularization strategies. Primary outcomes included 30-day, 1-year, and 5-year mortality. Multivariable analysis was used to define factors associated with major adverse cardiovascular and cerebrovascular events (MACCE). A total of 2869 patients with diabetes were divided into PCI (n = 653) and CABG (n = 2216) cohorts. Propensity matching yielded a 1:1 match consisting of 552 patients in each cohort (CABG vs PCI). Total median follow-up was 3.28 years (range: 1.83-5.00). Following propensity matching in patients with no prior PCI (1:1; n = 279), mortality remained significantly higher in the PCI cohort at 1 year (13.98% vs 7.53%; P = 0.014) and 5 years (26.88% vs 16.85%; P < 0.004). Hospital readmissions were higher for PCI patients at 1 year (16.49% vs 9.32%; P < 0.0122) and 5 years (19.71% vs 11.83%; P = 0.011). MACCE occurred more frequently in the PCI cohort (32.97% vs 21.51%; P = 0.002). Need for subsequent revascularization (6.45% vs 2.51%; P = 0.024) were significantly higher in the PCI cohort, and time interval to revascularization was significantly longer in the CABG cohort (3.48 [2.11-5.17] vs 2.62 [1.33-4.25] years; P < 0.001). The current study reports improved survival, fewer long-term hospital readmissions, and reduced MACCE and need for repeat revascularization in the CABG cohort. Given these data, patients with diabetes mellitus and coronary artery disease may fare better with surgical revascularization, compared to PCI.

Effects of Preoperative HbA1c Levels on the Postoperative Outcomes of Coronary Artery Disease Surgical Treatment in Patients with Diabetes Mellitus and Nondiabetic Patients: A Systematic Review and Meta-Analysis

AIMS

To investigate the effect of preoperative HbA1c levels on the postoperative outcomes of coronary artery disease surgery in diabetic and nondiabetic patients.

METHODS AND RESULTS

The MEDLINE (via PubMed), Cochrane Library, Web of Science, Embase, Wanfang Data, China National Knowledge Infrastructure (CNKI), and Chinese Biology Medicine (CBM) databases were used to search the effects of different preoperative HbA1c levels on the postoperative outcomes of coronary artery disease surgical treatment in diabetic and nondiabetic patients from inception to December 2018. Two review authors worked in an independent and duplicate manner to select eligible studies, extract data, and assess the risk of bias of the included studies. We used a meta-analysis to synthesize data and analyze subgroups, sensitivity, and publication bias as well as the GRADE methodology if appropriate. The literature search retrieved 886 records initially, and 23 cohort studies were included in the meta-analysis. In this meta-analysis, we found that there was a reduced incidence of surgical site infections (OR = 2.94, 95% CI 2.18-3.98), renal failure events (OR = 1.63, 95% CI 1.13-2.33), and myocardial infarction events (OR = 1.69, 95% CI 1.16-2.47), as well as a shortened hospital stay (MD = 1.08, 95% CI 0.46-1.71), in diabetic patients after coronary artery disease surgical treatment with lower preoperative HbA1c levels. For nondiabetic patients, a higher preoperative HbA1c level resulted in an increase in the incidence of mortality (OR = 2.23, 95% CI 1.01-4.90) and renal failure (OR = 2.33, 95% CI 1.32-4.12). No significant difference was found between higher and lower preoperative HbA1c levels in the incidence of mortality (OR = 1.06, 95% CI 0.88-1.26), stroke (OR = 1.49, 95% CI 0.94-2.37), or atrial fibrillation (OR = 0.94, 95% CI 0.67-1.33); the length of ICU stay (MD = 0.20, 95% CI -0.14-0.55); or sepsis incidence (OR = 2.49, 95% CI 0.99-6.25) for diabetic patients or for myocardial infarction events (OR = 1.32, 95% CI 0.27-6.31) or atrial fibrillation events (OR = 0.99, 95% CI 0.74-1.33) for nondiabetic patients. The certainty of evidence was judged to be moderate or low.

CONCLUSION

This meta-analysis showed that higher preoperative HbA1c levels may potentially increase the risk of surgical site infections, renal failure, and myocardial infarction and reduce the length of hospital stay in diabetic subjects after coronary artery disease surgical treatment and increase the risk of mortality and renal failure in nondiabetic patients. However, there was great inconsistency in defining higher preoperative HbA1c levels in the studies included; we still need high-quality RCTs with a sufficiently large sample size to further investigate this issue in the future. This trial is registered with CRD42019121531.

Association Between Hemoglobin A1c and Major Adverse Coronary Events in Patients with Diabetes Following Coronary Artery Bypass Surgery

INTRODUCTION

Diabetes is associated with a higher risk of major adverse coronary events (MACE) following coronary artery bypass grafting (CABG). Guidelines recommend disparate targets for glycemic control of patients with diabetes who have undergone CABG, ranging from a target hemoglobin A1c (HbA1c) of < 7.0% to 7.1-8.5%, based on data from non-CABG patients. To date, no study has evaluated the long-term impact of HbA1c concentrations on MACE post-CABG.

OBJECTIVE

To evaluate the association between HbA1c and MACE in CABG patients with diabetes.

METHODS

A secondary analysis of the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI2D) trial, which enrolled patients with type 2 diabetes and coronary artery disease, restricted to participants who underwent CABG with ≥ 1 HbA1c measurement post-CABG, was performed. The index date was date of first post-CABG HbA1c measurement. The primary outcome was MACE (composite of death, myocardial infarction, unstable angina, or repeat revascularization). Secondary outcomes included MACE components and heart failure. Cox proportional hazards models treating HbA1c as a time-dependent exposure (reference group: HbA1c 6.1-7.0%) were used to derive hazard ratios (HRs) with 95% confidence intervals adjusting for age, sex and baseline characteristics selected by stepwise regression.

RESULTS

A total of 549 patients were followed over a median 3.5 years. The median age of the cohort was 64 years, 25.1% were female, and median baseline HbA1c was 6.7%. Compared to achieving an HbA1c 6.1-7.0%, HbA1c > 8.0% was associated with an increased risk of MACE (HR 1.77, 1.01-3.10). This association was strongest for unstable angina (HR 5.21, 1.03-26.39). Achieving an HbA1c ≤ 6.0% was associated with an increased risk of death (HR 2.41, 1.01-5.74). Other comparisons were not statistically significant.

CONCLUSION

Among patients with type 2 diabetes who underwent CABG, achieving HbA1c 6.1-7.0% was associated with a lower risk of MACE and unstable angina versus achieving an HbA1c > 8.0% and lower risk of death versus achieving an HbA1c ≤ 6.0%.

Glycemic Control, Cardiac Autoimmunity, and Long-Term Risk of Cardiovascular Disease in Type 1 Diabetes Mellitus

BACKGROUND

Poor glycemic control is associated with increased risk of cardiovascular disease (CVD) in type 1 diabetes mellitus (T1DM); however, little is known about mechanisms specific to T1DM. In T1DM, myocardial injury can induce persistent cardiac autoimmunity. Chronic hyperglycemia causes myocardial injury, raising the possibility that hyperglycemia-induced cardiac autoimmunity could contribute to long-term CVD complications in T1DM.

METHODS

We measured the prevalence and profiles of cardiac autoantibodies (AAbs) in longitudinal samples from the DCCT (Diabetes Control and Complications Trial) in participants with mean hemoglobin A_1c (HbA_1c) ≥9.0% (n=83) and ≤7.0% (n=83) during DCCT. We assessed subsequent coronary artery calcification (measured once during years 7-9 in the post-DCCT EDIC [Epidemiology of Diabetes Interventions and Complications] observational study), high-sensitivity C-reactive protein (measured during EDIC years 4-6), and CVD events (defined as nonfatal myocardial infarction, stroke, death resulting from CVD, heart failure, or coronary artery bypass graft) over a 26-year median follow-up. Cardiac AAbs were also measured in matched patients with type 2 diabetes mellitus with HbA_1c ≥9.0% (n=70) and ≤7.0% (n=140) and, as a control for cardiac autoimmunity, patients with Chagas cardiomyopathy (n=51).

RESULTS

Apart from HbA_1c levels, the DCCT groups shared similar CVD risk factors at the beginning and end of DCCT. The DCCT HbA_1c ≥9.0% group showed markedly higher cardiac AAb levels than the HbA_1c ≤7.0% group during DCCT, with a progressive increase and decrease in AAb levels over time in the 2 groups, respectively ( P<0.001). In the HbA_1c ≥9.0% group, 46%, 22%, and 11% tested positive for ≥1, ≥2, and ≥3 different cardiac AAb types, respectively, similar to patients with Chagas cardiomyopathy, compared with 2%, 1%, and 0% in the HbA_1c ≤7.0% group. Glycemic control was not associated with AAb prevalence in type 2 diabetes mellitus. Positivity for ≥2 AAbs during DCCT was associated with increased risk of CVD events (4 of 6; hazard ratio, 16.1; 95% CI, 3.0-88.2) and, in multivariable analyses, with detectable coronary artery calcification (13 of 31; odds ratio, 60.1; 95% CI, 8.4-410.0). Patients with ≥2 AAbs subsequently also showed elevated high-sensitivity C-reactive protein levels (6.0 mg/L versus 1.4 mg/L in patients with ≤1 AAbs; P=0.003).

CONCLUSIONS

Poor glycemic control is associated with cardiac autoimmunity in T1DM. Furthermore, cardiac AAb positivity is associated with an increased risk of CVD decades later, suggesting a role for autoimmune mechanisms in the development of CVD in T1DM, possibly through inflammatory pathways.

Dietary fiber intake and glycemic control: coronary artery calcification in type 1 diabetes (CACTI) study

Background

Dietary fiber has been recommended for glucose control, and typically low intakes are observed in the general population. The role of fiber in glycemic control in reported literature is inconsistent and few reports are available in populations with type 1 diabetes (T1D).

Methods

Using data from the Coronary Artery Calcification in Type 1 Diabetes (CACTI) study [n = 1257; T1D: n = 568; non-diabetic controls: n = 689] collected between March 2000 and April 2002, we examined cross-sectional (baseline) and longitudinal (six-year follow-up in 2006–2008) associations of dietary fiber and HbA1c. Participants completed a validated food frequency questionnaire, and a physical examination and fasting biochemical analyses (12 h fast) at baseline visit and at the year 6 visit. We used a linear regression model stratified by diabetes status, and adjusted for age, sex and total calories, and diabetes duration in the T1D group. We also examined correlations of dietary fiber with HbA1c.

Results

Baseline dietary fiber intake and serum HbA1c in the T1D group were 16 g [median (IQ): 11–22 g) and 7.9 ± 1.3% mean (SD), respectively, and in the non-diabetic controls were 15 g [median (IQ): 11–21 g) and 5.4 ± 0.4%, respectively. Pearson partial correlation coefficients revealed a significant but weak inverse association of total dietary fiber with HbA1c when adjusted for age, sex, diabetes status and total calories (r = − 0.07, p = 0.01). In the adjusted linear regression model at baseline, total dietary fiber revealed a significant inverse association with HbA1c in the T1D group [β ± SE = − 0.32 ± 0.15, p = 0.034], as well as in the non-diabetic controls [− 0.10 ± 0.04, p = 0.009]. However, these results were attenuated after adjustment for dietary carbohydrates, fats and proteins, or for cholesterol and triglycerides. No such significance was observed at the year 6 follow-up, and with the HbA1c changes over 6 years.

Conclusion

Thus, at observed levels of intake, total dietary fiber reveals modest inverse associations with poor glycemic control. Future studies must further investigate the role of overall dietary quality adjusting for fiber-rich foods in T1D management.

Thymosin β4-mediated protective effects in the heart

INTRODUCTION

Despite recent advances in the treatment of coronary heart disease, a significant number of patients progressively develop heart failure. Reduction of infarct size after acute myocardial infarction and normalization of microvasculature in chronic myocardial ischemia could enhance cardiac survival.

AREAS COVERED

Induction of neovascularization using vascular growth factors has emerged as a promising novel approach for cardiac regeneration. Thymosin β4 (Tβ4) might be a promising candidate for the treatment of ischemic heart disease. It has been characterized as a major G-actin-sequestering factor regulating cell motility, migration, and differentiation. During cardiac development, Thymosin β4 seems essential for vascularization of the myocardium. In the adult organism, Thymosin β4 has anti-inflammatory properties, increases myocyte and endothelial cell survival accompanied by differentiation of epicardial progenitor cells. In chronic myocardial ischemia, Tβ4 overexpression enhances micro- and macrovasculature in the ischemic area and thereby improves myocardial function. A comparable effect is seen in diabetic and dyslipidemic pig ischemic hearts, suggesting an attractive therapeutic potential of adeno-associated virus encoding for Tβ4 for patients with ischemic heart disease.

EXPERT OPINION

Induction of mature micro-vessels is a prerequisite for chronic myocardial ischemia and might be achieved via a long-term overexpression of Thymosin β4.

Intensity of Glycemic Control Affects Long-Term Survival After Coronary Artery Bypass Graft Surgery

BACKGROUND

A patient's hemoglobin (Hb) A_1c level, regardless of diabetic status, is a measure of glycemic control. Studies have found it is an independent predictor of short-term death in patients undergoing coronary artery bypass grafting (CABG). In this study, we used preoperative HbA_1c to assess whether levels are associated with short-term and long-term survival after CABG.

METHODS

From a regional registry of consecutive cases, we identified 6,415 patients undergoing on-pump isolated CABG from 2008 to 2015 with documented preoperative HbA_1c level. We defined four HbA_1c groups: less than 5.7% (n = 1,713), 5.7% to 6.4% (n = 2,505), 6.5% to 8.0% (n = 1,377), and more than 8% (n = 820). Relationship to in-hospital outcomes and long-term survival was assessed. Outcome rates and hazard ratios were adjusted for patient and disease risk factors using multivariable logistic regression and Cox models.

RESULTS

The study included 3,740 patients (58%) not diagnosed as having diabetes and 2,674 with diabetes. Prediabetes (HbA_1c 5.7% to 6.4%) was documented in 52% (n = 1,933) of nondiabetic patients. Higher HbA_1c values were associated with younger age, female sex, greater body mass index, more comorbid diseases, lower ejection fraction, more 3-vessel coronary disease, and recent myocardial infarction (p < 0.05 trend for all). After adjustment for patient risk, greater HbA_1c values were not associated with higher rates of in-hospital death or morbidity. Long-term survival was significantly worse as HbA_1c increased. Risk of death increased by 13% for every unit increase in HbA_1c (adjusted hazard ratio, 1.13; 95% confidence interval, 1.07 to 1.19; p < 0.001).

CONCLUSIONS

Preadmission glycemic control, as assessed by HbA_1c, is predictive of long-term survival, with higher levels associated with poorer prognosis. Whether this risk can be modified by better glycemic control postoperatively remains to be determined.

Utility of glycated hemoglobin screening in patients undergoing elective coronary artery surgery: Prospective, cohort study from the E-CABG registry

BACKGROUND

Patients with increased glycated hemoglobin (HbA1c) seem to be at increased risk of sternal wound infection (SWI) after coronary artery bypass grafting (CABG). However, it is unclear whether increased baseline HbA1c levels may affect other postoperative outcomes.

MATERIAL AND METHODS

Data on preoperative levels of HbA1c were collected from 2606 patients undergoing elective isolated CABG from 2015 to 2016 and included in the prospective, multicenter E-CABG registry.

RESULTS

The prevalence of HbA1c ≥ 53 mmol/mol (7.0%) among non-diabetics was 5.3%, among non-insulin dependent diabetics was 53.5% and among insulin dependent diabetics was 67.1% (p < 0.001). The prevalence of HbA1c > 75 mmol/mol (9.0%) among non-diabetics was 0.5%, among non-insulin dependent diabetics was 5.8% and among insulin dependent diabetics was 10.6% (p < 0.001). Baseline levels of HbA1c ≥ 53 mmol/mol (7.0%) was a significant predictor of any SWI (10.7% vs. 3.3%, adjusted p-value: <0.001), deep SWI/mediastinitis (3.8% vs. 1.3%, adjusted p-value: 0.001) and acute kidney injury (27.4% vs. 19.8%, adjusted p-value: 0.042). These findings were confirmed in multilevel mixed effect logistic regression adjusted for participating centers. Among patients with diabetes, HbA1c ≥ 53 mmol/mol (7.0%) was predictive of SWI (11.1% vs. 4.8%, p = 0.001).

CONCLUSIONS

HbA1c is increased in a significant proportion of patients undergoing elective CABG and these patients are at higher risk of SWI. Less clear is the impact of increased HbA1c on other postoperative outcomes. These results do not support screening of HbA1c in patients without history of diabetes. Preoperative screening of HbA1c is valuable only to identify diabetics at risk of SWI.

Estimated glucose disposal rate predicts mortality in adults with type 1 diabetes

AIMS

This study aimed to investigate the association between insulin resistance as determined by the estimated glucose disposal rate (eGDR), and survival in adults with type 1 diabetes (T1D) in Sweden.

MATERIAL AND METHODS

Using the Swedish National Diabetes Register, indviduals with T1D were included from January 1, 2005 to December 31, 2012. Outcomes were retrieved from National healthcare registers. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated for the associations between eGDR (mg/kg/min) categorized into <4, 4 to 5.99, 6 to 7.99, and ≥8 (reference) and outcomes. Relative survival methods were used to compare survival to a matched Swedish reference population.

RESULTS

Among 17 050 included individuals with T1D, 10.5%, 20.2%, 20.5% and 48.9% had an eGDR of <4, 4 to 5.99, 6 to 7.99, and ≥8, respectively. Individuals with an eGDR <8 were older and had more comorbidities. During a median follow-up of 7.1 years, there were 946 (6%) deaths; 264 (15%), 367 (11%), 195 (6%) and 120 (1%) deaths occurred in individuals with an eGDR of <4, 4 to 5.99, 6 to 7.99 and ≥8, respectively. After adjustment for a wealth of different covariates including diabetes duration, age, sex and renal function, individuals with an eGDR <4, 4 to 5.99, and 6 to 7.99 had an increased risk of death compared to those with an eGDR ≥8 (adjusted HRs, 95% CIs, P values: 2.78, 2.04 to 3.77, <.001; 1.92, 1.49 to 2.46, <.001; 1.73, 1.34 to 2.21, <.001). Survival in individuals with an eGDR ≥8 was equal to a matched general population.

CONCLUSIONS

There is a strong association between eGDR and all-cause mortality, as well as cardiovascular mortality, in individuals with T1D. Our findings may guide preventive measures by improving risk assessment in individuals with T1D.

Glycaemic control and excess risk of major coronary events in persons with type 1 diabetes

OBJECTIVE

The excess risk of major coronary events (acute myocardial infarction (AMI) or death from coronary heart disease (CHD)) in individuals with type 1 diabetes (T1D) in relation to glycaemic control and renal complications is not known.

METHODS

Individuals with T1D in the Swedish National Diabetes Registry after 1 January 1998, without a previous MI (n=33 170) and 1 64 698 controls matched on age, sex and county were followed with respect to non-fatal AMI or death from CHD. Data were censored at death due to any cause until 31 December 2011.

RESULTS

During median follow-up of 8.3 and 8.9 years for individuals with T1D and controls, respectively, 1500 (4.5%) and 1925 (1.2%), experienced non-fatal AMI or died from CHD, adjusted HR 4.07 (95% CI 3.79 to 4.36). This excess risk increased with younger age, female sex, worse glycaemic control and severity of renal complications.The adjusted HR in men with T1D with updated mean haemoglobin A1c (HbA1c) <6.9% (52 mmol/mol) and normoalbuminuria was 1.30 (95% CI 0.90 to 1.88) and in women 3.16 (95% CI 2.14 to 4.65). HRs increased to 10.7 (95% CI 8.0 to 14.3) and 31.8 (95% CI 23.6 to 42.8) in men and women, respectively, with HbA1c >9.7% and renal complications.

CONCLUSIONS

The excess risk of AMI in T1D is substantially lower with good glycaemic control, absence of renal complications and men compared with women. In women, the excess risk of AMI or CHD death persists even among patients with good glycaemic control and no renal complications.

Diabetes Mellitus-Induced Microvascular Destabilization in the Myocardium

BACKGROUND

Diabetes mellitus causes microcirculatory rarefaction and may impair the responsiveness of ischemic myocardium to proangiogenic factors.

OBJECTIVES

This study sought to determine whether microvascular destabilization affects organ function and therapeutic neovascularization in diabetes mellitus.

METHODS

The authors obtained myocardial samples from patients with end-stage heart failure at time of transplant, with or without diabetes mellitus. Diabetic (db) and wild-type (wt) pigs were used to analyze myocardial vascularization and function. Chronic ischemia was induced percutaneously (day 0) in the circumflex artery. At day 28, recombinant adeno-associated virus (rAAV) (5 × 10¹² viral particles encoding vascular endothelial growth factor-A [VEGF-A] or thymosin beta 4 [Tβ4]) was applied regionally. CD31+ capillaries per high power field (c/hpf) and NG2+ pericyte coverage were analyzed. Global myocardial function (ejection fraction [EF] and left ventricular end-diastolic pressure) was assessed at days 28 and 56.

RESULTS

Diabetic human myocardial explants revealed capillary rarefaction and pericyte loss compared to nondiabetic explants. Hyperglycemia in db pigs, even without ischemia, induced capillary rarefaction in the myocardium (163 ± 14 c/hpf in db vs. 234 ± 8 c/hpf in wt hearts; p < 0.005), concomitant with a distinct loss of EF (44.9% vs. 53.4% in nondiabetic controls; p < 0.05). Capillary density further decreased in chronic ischemic hearts, as did EF (both p < 0.05). Treatment with rAAV.Tβ4 enhanced capillary density and maturation in db hearts less efficiently than in wt hearts, similar to collateral growth. rAAV.VEGF-A, though stimulating angiogenesis, induced neither pericyte recruitment nor collateral growth. As a result, rAAV.Tβ4 but not rAAV.VEGF-A improved EF in db hearts (34.5 ± 1.4%), but less so than in wt hearts (44.8 ± 1.5%).

CONCLUSIONS

Diabetes mellitus destabilized microvascular vessels of the heart, affecting the amplitude of therapeutic neovascularization via rAAV.Tβ4 in a translational large animal model of hibernating myocardium.

Association of Cardiovascular Risk Factors and Myocardial Fibrosis With Early Cardiac Dysfunction in Type 1 Diabetes: The Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications Study

OBJECTIVE

We investigated the association of cardiovascular risk factors and myocardial fibrosis with early cardiac dysfunction in type 1 diabetes.

RESEARCH DESIGN AND METHODS

Participants with type 1 diabetes aged 13-39 years without a known history of cardiovascular disease (CVD) (n = 1,441) were recruited into the Diabetes Control and Complications Trial (1983-1993) and subsequently followed in the Epidemiology of Diabetes Interventions and Complications study (1994 to present). Seven hundred fourteen participants underwent cardiac magnetic resonance (CMR) imaging (2007-2009) with late gadolinium enhancement sequences to assess ischemic and nonischemic scars and tagging sequences to evaluate circumferential strain. CMR-derived T1 mapping also was used to assess interstitial fibrosis. The influence of cardiovascular risk factors and myocardial scar on circumferential strain was assessed using linear regression.

RESULTS

Circumferential dysfunction was consistently associated with older age, male sex, smoking history, obesity, higher blood pressure, lower HDL cholesterol, and higher mean HbA1c. Participants with nonischemic scars (n = 16) had the worst circumferential function compared with those without scars (β ± SE 1.32 ± 0.60; P = 0.03). In sex-adjusted models, the correlation between T1 times and circumferential strain was not significant. In the fully adjusted models, a trend toward circumferential dysfunction in participants with nonischemic scars was found. Left ventricular ejection fraction was not associated with risk factors but was significantly lower if a myocardial scar was present.

CONCLUSIONS

Traditional CVD risk factors and elevated HbA1c levels are major factors related to early cardiac dysfunction in type 1 diabetes. Nonischemic myocardial scar, possibly as a marker of chronic exposure to known risk factors, may predict early cardiac dysfunction mediated by diffuse myocardial fibrosis as seen in diabetic cardiomyopathy.

Range of Risk Factor Levels: Control, Mortality, and Cardiovascular Outcomes in Type 1 Diabetes Mellitus

Supplemental Digital Content is available in the text.

Background:

Individuals with type 1 diabetes mellitus (T1DM) have a high risk of cardiovascular complications, but it is unknown to what extent fulfilling all cardiovascular treatment goals is associated with residual risk of mortality and cardiovascular outcomes in those with T1DM compared with the general population.

Methods:

We included all patients ≥18 years of age with T1DM who were registered in the Swedish National Diabetes Register from January 1, 1998, through December 31, 2014, a total of 33 333 patients, each matched for age and sex with 5 controls without diabetes mellitus randomly selected from the population. Patients with T1DM were categorized according to number of risk factors not at target: glycohemoglobin, blood pressure, albuminuria, smoking, and low-density lipoprotein cholesterol. Risk of all-cause mortality, acute myocardial infarction, heart failure hospitalization, and stroke was examined in relation to the number of risk factors at target.

Results:

The mean follow-up was 10.4 years in the diabetes group. Overall, 2074 of 33 333 patients with diabetes mellitus and 4141 of 166 529 controls died. Risk for all outcomes increased stepwise for each additional risk factor not at target. Adjusted hazard ratios for patients achieving all risk factor targets compared with controls were 1.31 (95% confidence interval [CI], 0.93–1.85) for all-cause mortality, 1.82 (95% CI, 1.15–2.88) for acute myocardial infarction, 1.97 (95% CI, 1.04–3.73) for heart failure hospitalization, and 1.17 (95% CI, 0.51–2.68) for stroke. The hazard ratio for patients versus controls with none of the risk factors meeting target was 7.33 (95% CI, 5.08–10.57) for all-cause mortality, 12.34 (95% CI, 7.91–19.48) for acute myocardial infarction, 15.09 (95% CI, 9.87–23.09) for heart failure hospitalization, and 12.02 (95% CI, 7.66–18.85) for stroke.

Conclusions:

A steep-graded association exists between decreasing number of cardiovascular risk factors at target and major adverse cardiovascular outcomes among patients with T1DM. However, risks for all outcomes were numerically higher for patients with T1DM compared with controls, even when all risk factors were at target, with risk for acute myocardial infarction and heart failure hospitalization statistically significantly higher.

Glycated Hemoglobin and Risk of Sternal Wound Infection After Isolated Coronary Surgery

BACKGROUND

Glycated hemoglobin (HbA1c) is a suspected risk factor for sternal wound infection (SWI) after CABG.Methods and Results:Data on preoperative HbA1c and SWI were available in 2,130 patients undergoing isolated CABG from the prospective E-CABG registry. SWI occurred in 114 (5.4%). Baseline HbA1c was significantly higher in patients with SWI (mean, 54±17 vs. 45±13 mmol/mol, P<0.0001). This difference was also observed in patients without a diagnosis of diabetes (P=0.027), in insulin-dependent diabetic (P=0.023) and non-insulin-dependent diabetic patients (P=0.034). In the overall series, HbA1c >70 mmol/mol (NGSP units, 8.6%) was associated with the highest risk of SWI (20.6% vs. 4.6%; adjusted OR, 5.01; 95% CI: 2.47-10.15). When dichotomized according to the cut-off 53 mmol/mol (NGSP units, 7.0%) as suggested both for diagnosis and optimal glycemic control of diabetes, HbA1c was associated with increased risk of SWI in the overall series (10.6% vs. 3.9%; adjusted OR, 2.09; 95% CI: 1.24-3.52), in diabetic patients (11.7% vs. 5.1%; adjusted OR, 2.69; 95% CI: 1.38-5.25), in patients undergoing elective surgery (9.9% vs. 2.7%; adjusted OR, 2.09; 95% CI: 1.24-3.52) and in patients with bilateral mammary artery grafts (13.7% vs. 4.8%; adjusted OR, 2.35; 95% CI: 1.17-4.69).

CONCLUSIONS

Screening for HbA1c before CABG may identify untreated diabetic patients, as well as diabetic patients with suboptimal glycemic control, at high risk of SWI.

Measuring the effects of CVD interventions and studies across socioeconomic groups: A brief review

There is a known socioeconomic skew in prevalence and outcomes of cardiovascular disease (CVD). To document the proportion of clinical trials and observational studies related to CVD recently published in peer-reviewed journals that report the socio-economic distributional differences in their outcomes. We undertook a review of peer-reviewed clinical trials and observational studies relating to CVD published between 01/06/2015-31/12/2015 in PubMed; and identified the proportion that included measures of socioeconomic status and the proportion that stratified results by, or controlled for, socioeconomic status when reporting outcomes. 414 peer reviewed publications reporting the outcomes of clinical trials or observational studies that related to CVD were identified. 32 of these reported on the socioeconomic status of participants. Of these, 20 stratified the results by socioeconomic status or adjusted the results for socioeconomic status. 18 studies measured education attainment, 5 measured income, 1 measured rurality and 1 measured occupation. Of the 414 articles reporting the outcomes of clinical trials or observational studies related to cardiovascular disease in 2015, the effectiveness of the intervention, or the differences in outcomes, between socioeconomic groups was assessed in 5% of studies. This lack of consideration of the effectiveness of trial outcomes or the differences in outcomes across socioeconomic groups impairs the ability of readers, healthcare professionals and policy makers to assess the impact of new treatments or interventions in closing the inequality gap associated with CVD.

Glycemic Control and Excess Cardiovascular Mortality in Type 1 Diabetes

Diabetes mellitus is a chronic systemic disease with multiple complications ranging from microvascular to macrovascular diseases. Type 1 diabetes comprises 5 % of adults with diabetes in the US. This population is shown to be at increased risk of cardiovascular events and mortality. Intensive glycemic control has been consistently associated with decreased microvascular complications but trials on macrovascular benefit yielded mixed results over the years. Recent data from long-term observational follow-up studies of major diabetes cardiovascular events and mortality are showing benefits that were not seen with the initial interventional trials. This article will review evidence on the effect of glycemic control on complications in diabetes mellitus with a focus on cardiovascular mortality in type 1 diabetes.