A history of diabetes predicts outcomes following myocardial infarction: an analysis of the 28 771 patients in the High-Risk MI Database

Cardiovascular Outcomes Among Patients with Acute Coronary Syndromes and Diabetes: Results from ACS QUIK Trial in India

Background

Despite cardiovascular disease being the leading cause of death in India, limited data exist regarding the factors associated with outcomes in patients with diabetes who suffer acute myocardial infarction (AMI).

Methods

We examined 21,374 patients with AMI enrolled in the ACS QUIK trial. We compared in-hospital and 30-day major adverse cardiac events including death, re-infarction, stroke, or major bleeding in those with and without diabetes. The associations between diabetes and cardiac outcomes were adjusted for presentation and in-hospital management using logistic regression.

Results

Mean ± SD age was 60.1 ± 12.0 years, 24.3% were females, and 44.4% had diabetes. Those with diabetes were more likely to be older, female, hypertensive, and have higher Killip class but less likely to present with STEMI. Patients with diabetes had longer symptoms onset-to-arrival (median 225 vs 290 min; P < 0.001) and, in case of STEMI, longer door-to-balloon times (median, 75 vs 91 min; P < 0.001). Diabetes was independently associated with higher in-hospital death (adjusted odds ratio [aOR], 1.46; 95% CI, 1.12-1.89), in-hospital reinfarction (aOR, 1.52; 95% CI, 1.15-2.02), 30-day MACE (aOR, 1.33; 95% CI, 1.14-1.55) and 30-day death (aOR, 1.40; 95%CI, 1.16-1.69) but not 30-day stroke or 30-day major bleeding.

Conclusion

Among patients presenting with AMI in Kerala, India, a considerable proportion has diabetes and are at increased risk for in-hospital and 30-day adverse cardiovascular outcomes. Increased awareness of the increased cardiovascular risk and attention to the implementation of established cardiovascular therapies are indicated for patients with diabetes in lower-middle-income countries who develop AMI.

Clinical Trial registration

ClinicalTrials.gov Unique identifier: NCT02256658.

Glycaemic control in people with diabetes following acute myocardial infarction

Diabetes is a highly prevalent disease associated with considerable cardiovascular end organ damage and mortality. Despite significant changes to the management of acute myocardial infarction over the last two decades, people with diabetes remain at risk of complications and mortality following a myocardial infarct for a multitude of reasons, including increased coronary atherosclerosis, associated coronary microvascular dysfunction, and diabetic cardiomyopathy. Dysglycaemia causes significant endothelial dysfunction and upregulation of inflammation within the vasculature and epigenetic changes mean that these deleterious effects may persist despite subsequent efforts to tighten glycaemic control. Whilst clinical guidelines advocate for the avoidance of both hyper- and hypoglcyaemia in the peri-infarct period, the evidence base is lacking, and currently there is no consensus on the benefits of glycaemic control beyond this period. Glycaemic variability contributes to the glycaemic milieu and may have prognostic importance following myocardial infarct. The use of continuous glucose monitoring means that glucose trends and parameters can now be captured and interrogated, and its use, along with newer medicines, may provide novel opportunities for intervention after myocardial infarction in people with diabetes.

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.

The ceRNA Crosstalk between mRNAs and lncRNAs in Diabetes Myocardial Infarction

Competitive endogenous RNA regulation suggests an intricate network of all transcriptional RNAs that have the function of repressing miRNA function and regulating mRNA expression. Today, the specific ceRNA regulatory mechanisms of lncRNA–miRNA–mRNA in patients who have diabetes mellitus (DM) and myocardial infarction (MI) are still unknown. Two data sets, GSE34198 and GSE112690, were rooted in the Gene Expression Omnibus database to search for changes of lncRNA, miRNA, and mRNA in MI patients with diabetes. Weighted gene correlation network analysis (WGCNA) was used to identify the modules related to the development of diabetes in patients with MI. Target genes of miRNAs were predicted using miRWalk, TargetScan, mirDB, RNA22, and miRanda. Then, functional and enrichment analyses were performed to build the lncRNA–miRNA–mRNA interaction network. We built ceRNA regulatory networks with three lncRNAs, two miRNAs, and nine mRNAs. Differentially expressed genes enriched in biological process, including neutrophil activation, refer to immune response and positive system of defense feedback. Besides, there is significant enrichment in molecular function of calcium toll−like receptor binding, icosanoid binding, RAGE receptor binding, and arachidonic acid binding. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis enriched differentially expressed genes (DEGs) in pathways that were well known in MI, indicating inflammation and immune response. Pathways associated with diabetes were also significantly enriched. We confirmed significantly altered lncRNA, miRNA, and mRNA in MI patients with diabetes, which might serve as biomarkers for the progress and development of diabetic cardiovascular diseases. We constructed a ceRNA regulatory network of lncRNA–miRNA–mRNA, which will enable us to understand the novel molecular mechanisms included in the initiation, progression, and interaction between DM and MI, laying the foundation for clinical diagnosis and treatment.

Treatment gaps, 1-year readmission and mortality following myocardial infarction by diabetes status, sex and socioeconomic disadvantage

AIMS

We evaluated variation in treatment for, and outcomes following, myocardial infarction (MI) by diabetes status, sex and socioeconomic disadvantage.

METHODS

We included all people aged ≥30 years who were discharged alive from hospital following MI between 1 July 2012 and 30 June 2017 in Victoria, Australia (n=43 272). We assessed receipt of inpatient procedures and discharge dispensing of cardioprotective medications for each admission, as well as 1-year all-cause, cardiovascular, and MI readmission rates and 1-year all-cause mortality.

RESULTS

Risk of all-cause (HR: 1.22 (1.19-1.26)), cardiovascular (1.29 (1.25-1.34)), MI (1.52 (1.43-1.62)) and heart failure readmission (1.62 (1.50-1.75)) and mortality (1.18 (1.11-1.26)) were higher in people with diabetes. Males and people in more disadvantaged areas were at increased risk of readmission and mortality following MI. People with diabetes (vs without) were more likely to receive coronary artery bypass grafting (CABG) but less likely to receive percutaneous coronary intervention (PCI) during, or within 30 days of, their index admission. Females were less likely to receive either (eg, 87% of males with a STEMI received PCI or CABG vs 70% of females), and people in more disadvantaged areas were less likely to receive PCI. People with diabetes, males and people in more disadvantaged areas were more likely to be dispensed cardioprotective medications at or within 90 days of discharge.

CONCLUSIONS

Following an MI, people with diabetes and males had poorer outcomes but received more intensive cardiovascular treatments. However, socioeconomic disadvantage was associated with both less intensive inpatient treatment and poorer outcomes.

A predictive model of perioperative myocardial infarction following elective spine surgery

Myocardial infarction (MI), and its predictive factors, has been an understudied complication following spine operations. The objective was to assess the risk factors for perioperative MI in elective spine surgery patients as a retrospective case control study. Elective spine surgery patients with a perioperative MI were isolated in the NSQIP. The relationship between MI and non-MI spine patients was assessed using chi-squared and independent samples t-tests. Univariate/multivariate analyses assessed predictive factors of MI. Logistic regression with stepwise model selection was employed to create a model to predict MI occurrence. The study included 196,523 elective spine surgery patients (57.1 yrs, 48%F, 30.4 kg/m²), and 436 patients with acute MI (Spine-MI). Incidence of MI did not change from 2010 to 2016 (0.2%-0.3%, p = 0.298). Spine-MI patients underwent more fusions than patients without MI (73.6% vs 58.4%, p < 0.001), with an average of 1.03 levels fused. Spine-MI patients also had significantly more SPO (5.0% vs 1.8%, p < 0.001) and 3CO (0.9% vs 0.2%, p < 0.001), but less decompression-only procedures (26.4% vs 41.6%, p < 0.001). Spine-MI underwent more revisions (5.3% vs 2.9%, p = 0.003), had greater invasiveness scores (3.41 vs 2.73, p < 0.001) and longer operative times (211.6 vs 147.3 min, p < 0.001). Mortality rate for Spine-MI patients was 4.6% versus 0.05% (p < 0.001). Multivariate modeling for Spine-MI predictors yielded an AUC of 83.7%, and included history of diabetes, cardiac arrest and PVD, past blood transfusion, dialysis-dependence, low preoperative platelet count, superficial SSI and days from operation to discharge. A model with good predictive capacity for MI after spine surgery now exists and can aid in risk-stratification of patients, consequently improving preoperative patient counseling and optimization in the peri-operative period.

Influence of diabetes mellitus interactions with cardiovascular risk factors on post-myocardial infarction heart failure hospitalizations

OBJECTIVE

There is a paucity of information regarding how cardiovascular risk factors (RF) modulate the impact of diabetes mellitus (DM) on the heart failure hospitalization (HFH) risk following an acute myocardial infarction (AMI).

METHODS

Adult survivors of an AMI were retrospectively identified from the 2014 US Nationwide Readmissions Database. The impact of DM on the risk for a 6-month HFH was studied in subgroups of RFs using multivariable logistic regression to adjust for baseline risk differences. Individual interactions of DM with RFs were tested.

RESULTS

Of 237,549 AMI survivors, 37.2% patients had DM. Primary outcome occurred in 12,934 patients (5.4%), at a 106% higher rate in DM patients (7.9% vs 4.0%, p < 0.001), which was attenuated to a 45% higher adjusted risk. Higher HFH risk in DM patients was consistent across subgroups and significant interactions were present between DM and other RFs. The increased HFH risk with DM was more pronounced in patients without certain HF RFs compared with those with these RFs [age < 65: OR for DM 1.84 (1.58-2.13) vs age ≥ 65: OR 1.34 (1.24-1.45); HF absent during index AMI: OR for DM 1.87 (1.66-2.10) vs HF present: OR 1.24 (1.14-1.34); atrial fibrillation absent: OR for DM 1.57 (1.46-1.68) vs present: OR 1.19 (1.06-1.33); P_interaction < 0.001 for all]. Similar results were noted for hypertension and chronic kidney disease.

CONCLUSIONS

AMI survivors with DM had a higher risk of 6-month HFHs. The impact of DM on the increased HFH risk was more pronounced in patients without certain RFs suggesting that more aggressive preventive strategies related to DM and HF are needed in these subgroups to prevent or delay the onset of HFHs.

Bioinformatic Analysis for Potential Biomarkers and Therapeutic Targets of T2DM-related MI

Background

Type 2 diabetes mellitus (T2DM), a major risk factor of coronary heart disease, is associated with an approximately twofold increase in the risk of myocardial infarction (MI). We studied co-expressed genes to demonstrate relationships between DM and MI and revealed the potential biomarkers and therapeutic targets of T2DM-related MI.

Methods

DM and MI-related differentially expressed genes (DEGs) were identified by bioinformatic analysis, Gene Expression Omnibus (GEO) datasets GSE42148 and GSE61144 of MI patients, and the normal control and GSE26168 and GSE15932 of DM patients and normal controls, respectively. Further target prediction and network analysis method were used to detect protein-protein interaction (PPI) networks, gene ontology (GO) terms, and pathway enrichment of DEGs. Co-expressed DEGs of T2DM-related MI were analyzed as well.

Results

We identified 210 upregulated and 127 downregulated DEGs in T2DM, as well as 264 upregulated and 242 downregulated DEGs in MI. Eighteen upregulated and four downregulated DEGs were identified as co-DEGs of T2DM and MI. Functional analysis revealed that T2DM-related DEGs were mostly enriched in the viral process and ubiquitin-mediated proteolysis, while MI-related DEGs were mostly enriched in protein phosphorylation and TNF signaling pathway. MPO, MMP9, CAMP, LTF, AZU1, DEFA4, STAT3, and PECAM1 were recognized as the hub genes of the co-DEGs with acceptable diagnostic values in T2DM and MI datasets. Adenosine receptor agonist IB-MECA was predicted to be a potential drug for T2DM-related MI with the highest CMap connectivity score.

Conclusion

Our study identified that the co-DEGs of MPO, MMP9, CAMP, LTF, AZU1, DEFA4, STAT3, and PECAM1 are significantly associated with novel biomarkers involved in T2DM-related MI. However, more experimental research and clinical trials are demanded to verify our results.

Association of diabetes and kidney function according to age and systolic function with the incidence of sudden cardiac death and non-sudden cardiac death in myocardial infarction survivors with heart failure

AIMS

An implantable cardioverter-defibrillator (ICD) is recommended for reducing the risk of sudden cardiac death (SCD) in myocardial infarction (MI) patients with a left ventricular ejection fraction (LVEF) ≤ 30%, as well as patients with a LVEF ≤ 35% and heart failure symptoms. Diabetes and/or impaired kidney function may confer additional SCD risk. We assessed the association between these two risk factors with SCD and non-SCD among MI survivors taking account of age and LVEF.

METHODS AND RESULTS

A total of 17 773 patients from the High-Risk MI Database were evaluated. Overall, diabetes and estimated glomerular filtration rate < 60 mL/min/1.73 m² , individually and together, conferred a higher risk of SCD [adjusted competing risk: hazard ratio (HR) 1.23, 1.23, and 1.32, respectively; all P < 0.03] and non-SCD (HR 1.34, 1.52, and 2.13, respectively; all P < 0.0001). Annual SCD rates in patients with LVEF > 35% and with diabetes, impaired kidney function, or both (2.0%, 2.5% and 2.7%, respectively) were comparable to rates observed in patients with LVEF 30-35% but no such risk factors (1.7%). However, these patients had also similarly higher non-SCD rates, such that the ratio of SCD to non-SCD was not increased. Importantly, this ratio was mostly dependent on age, with higher overall ratios in youngest subgroups (0.89 in patients < 55 years vs. 0.38 in patients ≥ 75 years), regardless of risk factors.

CONCLUSION

Although MI survivors with LVEF > 35% with diabetes, impaired kidney function, or both are at increased risk of SCD, the risk of non-SCD risk is even higher, suggesting an extension of the current indication for an ICD to them is unlikely to be worthwhile. MI survivors with low LVEF and aged < 55 years are likely to have the greatest potential benefit from ICD implantation.

Role of and Recent Evidence for Antiplatelet Therapy in Prevention of Cardiovascular Disease in Diabetes

PURPOSE OF REVIEW

When treating patients with diabetes mellitus (DM), the benefits of antiplatelet therapy in preventing cardiovascular disease must be weighed against an increased risk of bleeding. Recent trials have sought to determine both the optimal anti-platelet regimen for patients with DM, and who specifically requires medication among the DM population. This paper will review recent trials and evidence recommending the use of antiplatelet therapy in the prevention of cardiovascular disease in patients with diabetes.

RECENT FINDINGS

Seven notable trials assessed the effectiveness of antiplatelet therapy in the DM population. The ASCEND trial concluded 100 mg aspirin/day reduced rates of serious vascular events (OR 0.88, p < 0.01) but also increased rates of major bleeding events (OR 1.29, p < 0.01). The DAPT study revealed a longer dual antiplatelet regimen (30 months vs. 18 months) after coronary stent placement was more effective in reducing rates of stent thrombosis (0.5% vs. 1.1%, p = 0.06) and rates of myocardial infarction (3.5% vs. 4.8%, p = 0.06). DECLARE DIABETES showed that adding cilostazol to dual antiplatelet therapy after a coronary stent procedure reduced rates of in-stent and in-segment late loss and increased rates of revascularization (p < 0.04). In PEGASUS-TIMI, daily ticagrelor demonstrated reduced rates of major adverse cardiovascular and cerebrovascular events (OR 0.84, p < 0.04). The DAVID trial compared daily picotamide with daily aspirin therapy, finding reduced mortality rates in the picotamide group (OR 0.55, p < 0.05). Lastly, ACUITY found bivalirudin monotherapy resulted in lower rates of major bleeding events when compared to a glycoprotein IIb/IIa inhibitor and heparin or bivalirudin combination regimen (p < 0.01). Dual antiplatelet therapy guidelines still typically revolve around aspirin, but an increasing number of studies have demonstrated other drugs that may have a role in preventing atherosclerotic cardiovascular disease while decreasing the risk of major bleeding. Overall, it is wise to weigh the cardiovascular risk of a DM patient before prescribing antiplatelet medication. More research is necessary to determine a universal drug or combination of drugs that is safe and effective for DM patients.

Sodium-glucose Cotransporter 2 Inhibitors in Heart Failure: Potential Mechanisms of Action, Adverse Effects and Future Developments

Heart failure is a common complication in patients with diabetes, and people with both conditions present a worse prognosis. Sodium–glucose cotransporter 2 inhibitors (SGLT2Is) increase urinary glucose excretion, improving glycaemic control. In type 2 diabetes (T2D), some SGLT2Is reduce major cardiovascular events, heart failure hospitalisations and worsening of kidney function independent of glycaemic control. Multiple mechanisms (haemodynamic, metabolic, hormonal and direct cardiac/renal effects) have been proposed to explain these cardiorenal benefits. SGLT2Is are generally well tolerated, but can produce rare serious adverse effects, and the benefit/risk ratio differs between SGLT2Is. This article analyses the mechanisms underlying the cardiorenal benefits and adverse effects of SGLT2Is in patients with T2D and heart failure and outlines some questions to be answered in the near future.

Clinical impact of oral antidiabetic medications in heart failure patients

Heart failure (HF) is a common complication in patients with type 2 diabetes and it is closely associated with high morbidity and mortality rate. The incidence of cardiovascular events in patients with diabetes is related to high levels of glycemia, expressed by increase of HbA1c levels. However, there is little evidence to indicate that glycemic control can reduce the incidence of HF events in this population. Recently, several new antidiabetic drugs have been proposed although the exact clinical impact on heart failure occurrence and deterioration is under debate. Most common oral antidiabetic medication such as SGLT2, GLP-1 receptor agonist, metformin, and DPP4 inhibitor revealed peculiar metabolic and biomolecular signal effects. Moreover, the negative effects of thiazolidinediones on HF prognosis, on cardiac function, and exercise tolerance is of great interest. Conversely, several studies on GLP-1RA have highlighted many positive effects on cardiac myocytes, reducing apoptosis through cAMP/PKA/CRCB-mediated pathways protecting against oxidative stress. DPP-4 inhibitors have a controversial effect: saxagliptin and alogliptin may increase the risk of HF as opposed to vildagliptin and sitagliptin. Metformin increases myocardial ATP levels due to activation of 5-AMPK and this could explain the positive link between the drug and events rate reduction in diabetic patients with HF. The more interesting class of new drugs is SGLT2 inhibitors, that seems to have a positive effect on cardiac function by 38% reduction of HF incidence and mortality with empagliflozin treatment. In this review, we would analyze the specific effects of each class so as to better elucidate the clinical impact of antidiabetic drug on HF for guiding the clinicians in the choice of a best individualized therapy.

Diabetes mellitus, blood glucose and the risk of heart failure: A systematic review and meta-analysis of prospective studies

BACKGROUND AND AIM

The strength of the association between diabetes and risk of heart failure has differed between previous studies and the available studies have not been summarized in a meta-analysis. We therefore quantified the association between diabetes and blood glucose and heart failure in a systematic review and meta-analysis.

METHODS AND RESULTS

PubMed and Embase databases were searched up to May 3rd 2018. Prospective studies on diabetes mellitus or blood glucose and heart failure risk were included. A random effects model was used to calculate summary relative risks (RRs) and 95% confidence intervals (CIs). Seventy seven studies were included. Among the population-based prospective studies, the summary RR for individuals with diabetes vs. no diabetes was 2.06 (95% CIs: 1.73-2.46, I² = 99.8%, n = 30 studies, 401495 cases, 21416780 participants). The summary RR was 1.23 (95% CI: 1.15-1.32, I² = 78.2%, n = 10, 5344 cases, 91758 participants) per 20 mg/dl increase in blood glucose and there was evidence of a J-shaped association with nadir around 90 mg/dl and increased risk even within the pre-diabetic blood glucose range. Among the patient-based studies the summary RR was 1.69 (95% CI: 1.57-1.81, I² = 85.5%, p_{heterogeneity}<0.0001) for diabetes vs. no diabetes (n = 41, 100284 cases and >613925 participants) and 1.25 (95% CI: 0.89-1.75, I² = 95.6%, p_{heterogeneity}<0.0001) per 20 mg/dl increase in blood glucose (1016 cases, 34309 participants, n = 2). In the analyses of diabetes and heart failure there was low or no heterogeneity among the population-based studies that adjusted for alcohol intake and physical activity and among the patient-based studies there was no heterogeneity among studies with ≥10 years follow-up.

CONCLUSIONS

These results suggest that individuals with diabetes are at an increased risk of developing heart failure and there is evidence of increased risk even within the pre-diabetic range of blood glucose.

Editor’s Choice- Impact of insulin-treated diabetes on cardiovascular outcomes following high-risk myocardial infarction

Background:

Diabetes is associated with poor cardiovascular outcomes, and insulin-treated patients usually have a worse prognosis than non-insulin-treated subjects. The relationship between insulin treatment and outcomes in high-risk myocardial infarction patients has not been described in a large dataset.

Methods:

To investigate the association between insulin-treated diabetes and long-term cardiovascular outcomes in patients with high-risk myocardial infarction, we used adjusted Cox models to compare cardiovascular mortality and hospitalisation among 28,771 patients grouped by diabetes status and insulin treatment from four randomised clinical trials (VALIANT, EPHESUS, OPTIMAAL, CAPRICORN) of acute myocardial infarction complicated by heart failure and/or left ventricular systolic dysfunction.

Results:

After an approximately 2-year follow-up, patients with no diabetes (21,386 subjects, 74.3%), non-insulin-treated diabetes (4977 patients, 17.3%) and insulin-treated diabetes (2409 subjects, 8.4%) had an incremental yearly mortality risk (15.8%, 21.3% and 28.1%, respectively). Insulin-treated diabetes patients presented with a higher cardiovascular burden and comorbidities. After adjustment for 18 baseline covariates, patients with non-insulin-treated and insulin-treated diabetes were at higher risk of cardiovascular death (hazard ratio (HR) 1.25, 95% confidence interval (CI) 1.13–1.38 and HR 1.49, 95% CI 1.31–1.69, respectively; P for comparison of non-insulin-treated vs. insulin-treated diabetes =0.016) and cardiovascular hospitalisation (HR 1.33, 95% CI 1.25–1.41 and HR 1.16, 95% CI 1.11–1.22, respectively) compared to patients without diabetes. These results remained consistent after further adjustment for medications and left ventricular ejection fraction.

Conclusions:

Insulin-treated diabetes patients had higher event rates than diabetes patients taking oral treatments and patients without diabetes. However, insulin-treated diabetes patients had more comorbidities and atherosclerotic disease, precluding any causality suggestion between insulin treatment and outcomes. This high-risk population may require specific and/or more intense cardiovascular protective therapies.

Incremental burden of type 2 diabetes in patients experiencing cardiovascular hospitalizations

OBJECTIVE

To evaluate the incremental economic burden of type 2 diabetes in patients experiencing cardiovascular (CV) hospitalizations.

RESEARCH DESIGN AND METHODS

Adults with ≥1 CV hospitalization were identified using a US-based healthcare claims database from 1 July 2011 to 30 June 2014. Outcomes for patients surviving the index hospitalization were compared between patients with vs. without type 2 diabetes (cohorts were identified in the pre-index period). Subsequent CV hospitalizations were evaluated using Cox proportional hazards models. All-cause and CV-related healthcare resource utilization (HCRU) and costs captured on a per-patient per-month (PPPM) basis during a variable follow-up period were evaluated using appropriate multivariable regression models.

RESULTS

Of 316,207 patients with ≥1 CV hospitalization, 23% had comorbid type 2 diabetes. The mean age ± SD was 62.6 ± 12.3 years and 64.4% were male. During follow-up, the type 2 diabetes cohort had a 19% higher risk of subsequent CV hospitalizations compared to the non-type-2-diabetes cohort (p < .001). This difference in risk was highest in patients aged 35-44 years. Subsequent all-cause hospitalizations for the type 2 diabetes cohort were longer (mean length of stay, 6.7 vs. 6.3 days; p < .001), with higher total bed-days PPPM (mean, 0.52 vs. 0.43; p < .001), compared to the non-type-2-diabetes cohort. The type 2 diabetes cohort had a significantly higher incremental cost for both the index CV hospitalization (mean cost difference, $1046; p < .001) and all-cause costs PPPM following discharge (mean cost difference, $749; p < .001).

CONCLUSIONS

Comorbid type 2 diabetes was associated with an increased risk of subsequent CV hospitalizations and higher costs and HCRU during the follow-up period.

L-Carnitine: An Antioxidant Remedy for the Survival of Cardiomyocytes under Hyperglycemic Condition

BACKGROUND

Metabolic alterations as hyperglycemia and inflammation induce myocardial molecular events enhancing oxidative stress and mitochondrial dysfunction. Those alterations are responsible for a progressive loss of cardiomyocytes, cardiac stem cells, and consequent cardiovascular complications. Currently, there are no effective pharmacological measures to protect the heart from these metabolic modifications, and the development of new therapeutic approaches, focused on improvement of the oxidative stress condition, is pivotal. The protective effects of levocarnitine (LC) in patients with ischemic heart disease are related to the attenuation of oxidative stress, but LC mechanisms have yet to be fully understood.

OBJECTIVE

The aim of this work was to investigate LC's role in oxidative stress condition, on ROS production and mitochondrial detoxifying function in H9c2 rat cardiomyocytes during hyperglycemia.

METHODS

H9c2 cells in the hyperglycemic state (25 mmol/L glucose) were exposed to 0.5 or 5 mM LC for 48 and 72 h: LC effects on signaling pathways involved in oxidative stress condition were studied by Western blot and immunofluorescence analysis. To evaluate ROS production, H9c2 cells were exposed to H₂O₂ after LC pretreatment.

RESULTS

Our in vitro study indicates how LC supplementation might protect cardiomyocytes from oxidative stress-related damage, preventing ROS formation and activating antioxidant signaling pathways in hyperglycemic conditions. In particular, LC promotes STAT3 activation and significantly increases the expression of antioxidant protein SOD2. Hyperglycemic cardiac cells are characterized by impairment in mitochondrial dysfunction and the CaMKII signal: LC promotes CaMKII expression and activation and enhancement of AMPK protein synthesis. Our results suggest that LC might ameliorate metabolic aspects of hyperglycemic cardiac cells. Finally, LC doses herein used did not modify H9c2 growth rate and viability.

CONCLUSIONS

Our novel study demonstrates that LC improves the microenvironment damaged by oxidative stress (induced by hyperglycemia), thus proposing this nutraceutical compound as an adjuvant in diabetic cardiac regenerative medicine.

Biological properties of cardiac mesenchymal stem cells in rats with diabetic cardiomyopathy

Cardiomyopathy is a major outcome in patients with diabetes mellitus (DM) and contributes to the high morbidity/mortality observed in this disease.

AIMS

To evaluate several biological properties of cardiac mesenchymal stem cells (cMSCs) in a rat model of streptozotocin-induced DM with concomitant diabetic cardiomyopathy.

MAIN METHODS

After 10weeks of DM induction, diabetic and control rats were assessed using ECG and ventricular hemodynamics monitoring. Then, the hearts were excised and processed for histology and for extracting non-cardiomyocytic cells. A pool of these cells was plated for a colony forming units-fibroblasts (CFU-F) assay in order to estimate the number of cMSCs. The remaining cells were expanded to assess their proliferation rate as well as their osteogenic and adipogenic differentiation ability.

KEY FINDINGS

DM rats presented intense hyperglycemia and changes in ECG, LV hemodynamic, cardiac mass index and fibrosis, indicating presence of DCM. The CFU-F assay revealed a higher number of cardiac CFU-Fs in DM rats (10.4±1.1CFU-F/10⁵ total cells versus 7.6±0.7CFU-F/10⁵ total cells in control rats, p<0.05), which was associated with a significantly higher proliferative rate of cMSCs in DM rats. In contrast, cMSCs from DM rats presented a lower capacity to differentiate into both osteogenic (20.8±4.2% versus 10.1±1.0% in control rats, p<0.05) and adipogenic lineages (4.6±1.0% versus 1.3±0.5% in control rats, p<0.05).

SIGNIFICANCE

The findings suggest, for the first time, that in chronic DM rats with overt DCM, cMSCs increase in number and exhibit changes in several functional properties, which could be implicated in the pathogenesis of diabetic cardiomyopathy.

Concise Review: Challenges in Regenerating the Diabetic Heart: A Comprehensive Review

Stem cell therapy is one of the promising regenerative strategies developed to improve cardiac function in patients with ischemic heart diseases (IHD). However, this approach is limited in IHD patients with diabetes due to a progressive decline in the regenerative capacity of stem cells. This decline is mainly attributed to the metabolic memory incurred by diabetes on stem cell niche and their systemic cues. Understanding the molecular pathways involved in the diabetes-induced deterioration of stem cell function will be critical for developing new cardiac regeneration therapies. In this review, we first discuss the most common molecular alterations occurring in the diabetic stem cells/progenitor cells. Next, we highlight the key signaling pathways that can be dysregulated in a diabetic environment and impair the mobilization of stem/progenitor cells, which is essential for the transplanted/endogenous stem cells to reach the site of injury. We further discuss the possible methods of preconditioning the diabetic cardiac progenitor cell (CPC) with an aim to enrich the availability of efficient stem cells to regenerate the diseased diabetic heart. Finally, we propose new modalities for enriching the diabetic CPC through genetic or tissue engineering that would aid in developing autologous therapeutic strategies, improving the proliferative, angiogenic, and cardiogenic properties of diabetic stem/progenitor cells. Stem Cells 2017;35:2009-2026.