Association of hypoglycemia and cardiac ischemia: a study based on continuous monitoring

Absolute risk of acute coronary syndrome after severe hypoglycemia: A population-based 2-year cohort study using the National Database in Japan

AIMS/INTRODUCTION

Although the epidemiological relationship between hypoglycemia and increased risk of acute coronary syndrome (ACS) has been well established, the time period for increased risk of ACS after a severe hypoglycemic episode remains unknown. The present study aimed to determine the ACS risk after a severe hypoglycemic episode.

MATERIALS AND METHODS

We carried out a retrospective population-based cohort study based on national claims data in Japan. We retrieved data of diabetes patients aged ≥35 years collected from April 2014 to March 2016. The absolute risk of ACS was defined as the occurrence of an emergency percutaneous coronary intervention after a severe hypoglycemic episode.

RESULTS

In total, data of 7,909,626 patients were included in the analysis. The absolute risk of ACS was 2.9 out of 1,000 person-years in all patients. ACS risk in patients with severe hypoglycemic episodes was 3.0 out of 1,000 person-years. Severe hypoglycemic episodes increased the absolute risk of ACS in patients aged ≥70 years, but not in patients aged <70 years. The absolute risk of ACS was 10.6 out of 1,000 person-years within 10 days of a severe hypoglycemic episode. There was a significant trend between shorter duration after an episode and higher ACS risk.

CONCLUSIONS

Severe hypoglycemia was associated with an increased risk of ACS in elderly diabetes patients. ACS risk increased with a shorter period after a severe hypoglycemic episode, suggesting that severe hypoglycemia leads to an increased risk of ACS in diabetes patients. These findings show that it is important to avoid severe hypoglycemia while treating diabetes, particularly in elderly patients.

Confirming the Bidirectional Nature of the Association Between Severe Hypoglycemic and Cardiovascular Events in Type 2 Diabetes: Insights From EXSCEL

OBJECTIVE

We sought to confirm a bidirectional association between severe hypoglycemic events (SHEs) and cardiovascular (CV) event risk and to characterize individuals at dual risk.

RESEARCH DESIGN AND METHODS

In a post hoc analysis of 14,752 Exenatide Study of Cardiovascular Event Lowering (EXSCEL) participants, we examined time-dependent associations between SHEs and subsequent major adverse cardiac events (CV death, nonfatal myocardial infarction [MI] or stroke), fatal/nonfatal MI, fatal/nonfatal stroke, hospitalization for acute coronary syndrome (hACS), hospitalization for heart failure (hHF), and all-cause mortality (ACM), as well as time-dependent associations between nonfatal CV events and subsequent SHEs.

RESULTS

SHEs were uncommon and not associated with once-weekly exenatide therapy (hazard ratio 1.13 [95% CI 0.94-1.36], P = 0.179). In fully adjusted models, SHEs were associated with an increased risk of subsequent ACM (1.83 [1.38-2.42], P < 0.001), CV death (1.60 [1.11-2.30], P = 0.012), and hHF (2.09 [1.37-3.17], P = 0.001), while nonfatal MI (2.02 [1.35-3.01], P = 0.001), nonfatal stroke (2.30 [1.25-4.23], P = 0.007), hACS (2.00 [1.39-2.90], P < 0.001), and hHF (3.24 [1.98-5.30], P < 0.001) were all associated with a subsequent increased risk of SHEs. The elevated bidirectional time-dependent hazards linking SHEs and a composite of all CV events were approximately constant over time, with those individuals at dual risk showing higher comorbidity scores compared with those without.

CONCLUSIONS

These findings, showing greater risk of SHEs after CV events as well as greater risk of CV events after SHEs, validate a bidirectional relationship between CV events and SHEs in patients with high comorbidity scores.

Association of Longitudinal Values of Glycated Hemoglobin With Cardiovascular Events in Patients With Type 2 Diabetes and Multivessel Coronary Artery Disease

IMPORTANCE

Glycated hemoglobin (HbA1c) values are used to guide glycemic control, but in patients with type 2 diabetes and multivessel coronary artery disease (CAD), the association of the longitudinal values of HbA1c with cardiovascular outcomes is unclear.

OBJECTIVE

To assess whether longitudinal variation of HbA1c is associated with cardiovascular events in long-term follow-up among patients with diabetes and multivessel CAD.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included 888 patients with type 2 diabetes and multivessel CAD in the Medicine, Angioplasty, or Surgery Study (MASS) Registry of the Heart Institute of the University of São Paulo from January 2003 to December 2007. Data were analyzed from January 15, 2018, to October 15, 2019.

EXPOSURE

Longitudinal HbA1c values.

MAIN OUTCOMES AND MEASURES

The combined outcome of all-cause mortality, myocardial infarction, and ischemic stroke.

RESULTS

Of 888 patients with type 2 diabetes and multivessel CAD, 725 (81.6%; median [range] age, 62.4 [55.7-68.0] years; 467 [64.4%] men) had complete clinical and HbA1c information during a median (interquartile range) follow-up period of 10.0 (8.0-12.3) years, with a mean (SD) of 9.5 (3.8) HbA1c values for each patient. The composite end point of death, myocardial infarction, or ischemic stroke occurred in 262 patients (36.1%). A 1-point increase in the longitudinal value of HbA1c was significantly associated with a 14% higher risk of the combined end point of all-cause mortality, myocardial infarction, and ischemic stroke (hazard ratio, 1.14; 95% CI, 1.04-1.24; P = .002) in the unadjusted analysis. After adjusting for baseline factors (ie, age, sex, 2-vessel or 3-vessel CAD, initial CAD treatments, ejection fraction, and creatinine and low-density lipoprotein cholesterol levels), a 1-point increase in the longitudinal value of HbA1c was associated with a 22% higher risk of the combined end point (hazard ratio, 1.22; 95% CI, 1.12-1.35; P < .001).

CONCLUSIONS AND RELEVANCE

Longitudinal increase of HbA1c was independently associated with higher rates of cardiovascular events in patients with type 2 diabetes and multivessel CAD.

Early Endothelial Dysfunction in Type 1 Diabetes Is Accompanied by an Impairment of Vascular Smooth Muscle Function: A Meta-Analysis

Background: A large yet heterogeneous body of literature exists suggesting that endothelial dysfunction appears early in type 1 diabetes, due to hyperglycemia-induced oxidative stress. The latter may also affect vascular smooth muscles (VSM) function, a layer albeit less frequently considered in that pathology. This meta-analysis aims at evaluating the extent, and the contributing risk factors, of early endothelial dysfunction, and of the possible concomitant VSM dysfunction, in type 1 diabetes. Methods: PubMed, Web of Sciences, Cochrane Library databases were screened from their respective inceptions until October 2019. We included studies comparing vasodilatory capacity depending or not on endothelium (i.e., endothelial function or VSM function, respectively) in patients with uncomplicated type 1 diabetes and healthy controls. Results: Fifty-eight articles studying endothelium-dependent function, among which 21 studies also assessed VSM, were included. Global analyses revealed an impairment of standardized mean difference (SMD) (Cohen's d) of endothelial function: -0.61 (95% CI: -0.79, -0.44) but also of VSM SMD: -0.32 (95% CI: -0.57, -0.07). The type of stimuli used (i.e., exercise, occlusion-reperfusion, pharmacological substances, heat) did not influence the impairment of the vasodilatory capacity. Endothelial dysfunction appeared more pronounced within macrovascular than microvascular beds. The latter was particularly altered in cases of poor glycemic control [HbA_1c > 67 mmol/mol (8.3%)]. Conclusions: This meta-analysis not only corroborates the presence of an early impairment of endothelial function, even in response to physiological stimuli like exercise, but also highlights a VSM dysfunction in children and adults with type 1 diabetes. Endothelial dysfunction seems to be more pronounced in large than small vessels, fostering the debate on their relative temporal appearance.

Association of glycemic variability with left ventricular diastolic function in type 2 diabetes mellitus

Background

Type 2 diabetes mellitus (T2DM) is a major cause of heart failure (HF) with preserved ejection fraction (HFpEF), usually presenting as left ventricular (LV) diastolic dysfunction. Thus, LV diastolic function should be considered a crucial marker of a preclinical form of DM-related cardiac dysfunction. However, the impact of glycemic variability (GV) on LV diastolic function in such patients remains unclear.

Methods

We studied 100 asymptomatic T2DM patients with preserved LV ejection fraction (LVEF) without coronary artery disease (age: 60 ± 14 years, female: 45%). GV was evaluated as standard deviation of blood glucose level using continuous glucose monitoring system for at least 72 consecutive hours. LV diastolic function was defined as mitral inflow E and mitral e’ annular velocities (E/e’), and > 14 was determined as abnormal.

Results

E/e’ in patients with high GV (≥ 35.9 mg/dL) was significantly higher than that in patients with low GV (11.3 ± 3.9 vs. 9.8 ± 2.8, p = 0.03) despite similar age, gender-distribution, and hemoglobin A1c (HbA1c). Multivariate logistic regression analysis showed that GV ≥ 35.9 mg/dL (odds ratio: 3.67; 95% confidence interval: 1.02–13.22; p < 0.05) was an independently associated factor, as was age, of E/e’ > 14. In sequential logistic models for the associations of LV diastolic dysfunction, one model based on clinical variables including age, gender and hypertension was not improved by addition of HbA1c (p = 0.67) but was improved by addition of high GV (p = 0.04).

Conclusion

Since HFpEF is a syndrome caused by diverse agents, reducing GV may represent a potential new therapeutic strategy for the prevention of the development of HFpEF in T2DM patients.

Outcomes Associated With the Adjunctive Use of Dipeptidyl Peptidase-4 Inhibitors With Insulin Versus Other Antihyperglycemic Medications in Patients With Prediabetes or Diabetes After Cardiac Surgery

BACKGROUND

Dipeptidyl peptidase-4 inhibitors (DPP-4i) plus basal insulin is noninferior to insulin monotherapy for glycemic control in medical-surgical patients, but data in postoperative cardiac surgery patients are sparse.

OBJECTIVE

To compare glucose control in postoperative cardiac surgery patients with prediabetes or diabetes receiving a DPP-4i plus insulin versus other antihyperglycemic regimens.

METHODS

We retrospectively identified patients with prediabetes or diabetes who underwent cardiac surgery at our hospital between May 2016 and June 2017. Included patients were stratified into cohorts: (1) DPP-4i plus insulin and (2) other antihyperglycemic regimens. Blood glucose levels were collected on postoperative days 2 to 7. Uncontrolled glucose (≥2 measurements <80 or >180 mg/dL in 1 day), hyperglycemia (>2 measurements ≥180 mg/dL in 1 day), and hypoglycemia (any measurement <70 mg/dL) were compared between cohorts using logistic regression adjusted for home antihyperglycemics.

RESULTS

We included 135 cardiac surgery patients, of which 65 received DPP-4i plus insulin. Eighty-two patients received antihyperglycemics at home. Uncontrolled glucose occurred in 61 (45.2%) patients; while hyperglycemia and hypoglycemia occurred in 50 (37.0%) and 24 (17.8%) patients, respectively. There was no difference in the adjusted odds of uncontrolled glucose (odds ratio [OR] = 1.43; 95% confidence interval [CI] = 0.65-3.11), hyperglycemia (OR = 1.20; 95% CI = 0.52-2.78), or hypoglycemia (OR = 0.69; 95% CI = 0.27-1.75) for those receiving DPP-4i plus insulin versus other regimens.

CONCLUSION

Glucose control was no different among postoperative cardiac surgery patients receiving a DPP-4i plus insulin versus other regimens. DPP-4i use was not associated with hypoglycemia.

Severe hypoglycemia and the risk of cardiovascular disease and mortality in type 2 diabetes: a nationwide population-based cohort study

BACKGROUND

We investigated the association regarding severe hypoglycemia episodes with cardiovascular disease risk and all-cause mortality in patients with type 2 diabetes.

METHODS

Baseline and follow-up data (n = 1,568,097) from patients with type 2 diabetes were retrieved from the National Health Insurance System database (covering the entire Korean population). Type 2 diabetes, severe hypoglycemia, and major comorbidities were identified using International Classification of Diseases 10 codes and medication information. Individuals who were classified as type 2 diabetes in the year of 2009 were screened, and we counted severe hypoglycemia episodes from 2007 to 2009. The primary outcome was newly developed myocardial infarction (MI), stroke, heart failure, or all-cause mortality. Participants were followed from the baseline index date to the date of death or until December 31, 2015.

RESULTS

In total, 19,660 (1.2%) patients developed at least one severe hypoglycemia event during the period from 2007 to 2009. Mean follow-up was 5.7 years. After adjustment for confounding factors, the hazard ratio (HR) of MI significantly and sequentially increased: 0 vs. 1 episode, HR 1.56, 95% CI 1.46-1.64; 0 vs. 2 episodes, HR 1.86, 95% CI 1.61-2.15; 0 vs. 3 or more episodes, HR 1.86, 95% CI 1.48-2.35, P for trend < 0.001. Similar findings were noted regarding the relationship of severe hypoglycemia episodes with stroke, heart failure, and all-cause mortality. Risks for all outcomes were highest within 1 year from the index date and showed decreasing trends with follow-up. Sensitivity analyses of the data from the subgroup population and 797,544 subjects who received a national health examination did not change the significance of the main findings.

CONCLUSION

Among adult Korean patients with type 2 diabetes, a severe hypoglycemia episode is associated with increased risk for cardiovascular outcomes and all-cause mortality. Significant results from dose-response, temporal, and sensitivity analyses may suggest the possibility of direct causality between severe hypoglycemia and cardiovascular outcomes and mortality.

Hypoglycaemia, cardiovascular disease, and mortality in diabetes: epidemiology, pathogenesis, and management

Hypoglycaemia has long been recognised as a dangerous side-effect of treatment of diabetes with insulin or insulin secretagogues. With its potential to disrupt cerebral function, hypoglycaemia can have a major effect on peoples' lives. Study findings have suggested that hypoglycaemia is associated with an increased risk of cardiovascular events and mortality. Different mechanisms by which hypoglycaemia might provoke cardiovascular events have been identified in experimental studies, and in clinical studies cardiac arrhythmias have been reported to be induced by hypoglycaemia, with one report describing sudden death during a severe episode. Emerging evidence suggests that the association between hypoglycaemia and cardiovascular events and mortality is likely to be multifactorial. The association is probably partly caused by confounding, with hypoglycaemia occurring more frequently in people with comorbidities who are also more likely to die than those without. However, people with type 1 or type 2 diabetes also seem at risk of hypoglycaemia-induced cardiovascular effects. This risk should be recognised by clinicians when agreeing glycaemic goals with patients and choosing appropriate glucose-lowering therapies.

Use of incretin-based therapy in hospitalized patients with hyperglycemia

OBJECTIVE

Hyperglycemia is common in hospitalized patients with and without prior history of diabetes and is an independent marker of morbidity and mortality in critically and noncritically ill patients. Tight glycemic control using insulin has been shown to reduce cardiac morbidity and mortality in hospitalized patients, but it also results in hypoglycemic episodes, which have been linked to poor outcomes. Thus, alternative treatment options that can normalize blood glucose levels without undue hypoglycemia are being sought. Incretin-based therapies, such as glucagon-like peptide (GLP)-1 receptor agonists (RAs) and dipeptidyl peptidase (DPP)-4 inhibitors, may have this potential.

METHODS

A PubMed database was searched to find literature describing the use of incretins in hospital settings. Title searches included the terms "diabetes" (care, management, treatment), "hospital," "inpatient," "hypoglycemia," "hyperglycemia," "glycemic," "incretin," "dipeptidyl peptidase-4 inhibitor," "glucagon-like peptide-1," and "glucagon-like peptide-1 receptor agonist."

RESULTS

The preliminary research experience with native GLP-1 therapy has shown promise, achieving improved glycemic control with a low risk of hypoglycemia, counteracting the hyperglycemic effects of stress hormones, and improving cardiac function in patients with heart failure and acute ischemia. Large, randomized controlled clinical trials are necessary to determine whether these favorable results will extend to the use of GLP-1 RAs and DPP-4 inhibitors.

CONCLUSIONS

This review offers hospitalist physicians and healthcare providers involved in inpatient diabetes care a pathophysiologic-based approach for the use of incretin agents in patients with hyperglycemia and diabetes, as well as a summary of benefits and concerns of insulin and incretin-based therapy in the hospital setting.

Assessment of risk of fasting during Ramadan under optimal diabetes care, in high-risk patients with diabetes and coronary heart disease through the use of FreeStyle Libre flash continuous glucose monitor (FSL-CGMS)

AIM

Most of Muslims patients with diabetes and Coronary Heart Disease (CHD) elect to fast in Ramadan, but the actual risk in this subset of patients with diabetes is largely unknown. We aimed to understand the safety of fasting in CHD patients with diabetes insisting on fasting Ramadan under optimal care. We also monitored the change in biophysical and biochemical parameters of these patients before and after Ramadan. We conducted this prospective study in a tertiary care hospital in Dubai during Ramadan 2016, (June 6th till July 5th).

PATIENTS AND METHODS

21 Patients with T2DM with stable known CHD during the three months prior to study and insisted on fasting despite advice against it were recruited for the study. All patients received continuous glucose monitoring with free style libre monitoring device (FSL-CGM) during and outside Ramadan period. We recorded DM or CVD-related emergency visit or hospitalisation, change in BMI, systolic and diastolic BP, lipids profile, e-GFR, HBA1c, and frequency of hypoglycemia during Ramadan fasting and not -fasting period.

RESULTS

This is first study using CGM in CHD patients with diabetes who observe fast in Ramadan. Patients had a significantly higher incidence (3.2 ± 2.8 vs 1.1 ± 1.6 episodes, p = 0.033) and prolonged duration of hypoglycemia (117.8 ± 87.2, 49.1 ± 59.1 min p 0.022) during fasting compared to non-fasting respectively. No significant alteration was seen in BMI, SBP and DBP, lipid profile and renal function. There is a significant improvement in HBA1c during Ramadan.

CONCLUSION

We could not associate any adverse cardiovascular effects with fasting Ramadan in patients with stable CHD under optimal diabetes care. FSL-CGMS data showed higher frequency of hypoglycemia during Ramadan fasting. Studies with larger sample size are needed for further validation of these findings.

Metabolic and proteomic signatures of hypoglycaemia in type 2 diabetes

AIMS

To determine the biochemical changes that underlie hypoglycaemia in a healthy control group and in people with type 2 diabetes (T2D).

MATERIALS AND METHODS

We report a hypoglycaemic clamp study in seven healthy controls and 10 people with T2D. Blood was withdrawn at four time points: at baseline after an overnight fast; after clamping to euglycaemia at 5 mmol/L; after clamping to hypoglycaemia at 2.8 mmol/L; and 24 hours later, after overnight fast. Deep molecular phenotyping using non-targeted metabolomics and the SomaLogic aptamer-based proteomics platform was performed on collected samples.

RESULTS

A total of 955 metabolites and 1125 proteins were identified, with significant alterations in >90 molecules. A number of metabolites significantly increased during hypoglycaemia, but only cortisol, adenosine-3',5'-cyclic monophosphate (cyclic AMP), and pregnenolone sulphate, were independent of insulin. By contrast, identified protein changes were triggered by hypoglycaemia rather than insulin. The T2D group had significantly higher levels of fatty acids including 10-nonadecenoate, linolenate and dihomo-linoleate during hypoglycaemia compared with the control group. Molecules contributing to cardiovascular complications such as fatty-acid-binding protein-3 and pregnenolone sulphate were altered in the participants with T2D during hypoglycaemia. Almost all molecules returned to baseline at 24 hours.

CONCLUSIONS

The present study provides a comprehensive description of molecular events that are triggered by insulin-induced hypoglycaemia. We identified deregulated pathways in T2D that may play a role in the pathophysiology of hypoglycaemia-induced cardiovascular complications.

Review of the cardiovascular safety of dipeptidyl peptidase-4 inhibitors and the clinical relevance of the CAROLINA trial

BACKGROUND

Cardiovascular (CV) disease (CVD) is a well-recognized complication of type 2 diabetes mellitus (T2DM) and there is a clinical need for glucose-lowering therapies that do not further increase CV risk in this population. Although sulfonylureas (SUs) may be used as second-line therapy for patients requiring additional therapy after first-line metformin to improve glycemic control, their long-term effects on CV outcomes remain uncertain, and a wide range of alternative agents exist including dipeptidyl peptidase-4 (DPP-4) inhibitors.

METHODS

Literature searches in PubMed (2013-2018) were conducted with terms for DPP-4 inhibitors combined with CV terms, with preference given to cardiovascular outcomes trials (CVOTs). Reference lists from retrieved articles and diabetes guidelines were also considered.

RESULTS

This narrative review discusses current evidence for the CV safety of these agents, describes the long-term CV effects of DPP-4 inhibitors, including effects on CV events, mortality, the risk for heart failure hospitalization, and highlights the need for further research into the CV effects of SU therapy. Although SUs remain a treatment option for T2DM, the long-term effects of these agents on CV outcomes are unclear, and further long-term studies are required. For DPP-4 inhibitors, uncertainties have been raised about their long-term effect on hospitalization for heart failure in light of the results of SAVOR-TIMI 53, although the findings of other DPP-4 inhibitor CVOTs in T2DM and data analyses have suggested these agents do not increase the occurrence of adverse CV outcomes.

CONCLUSIONS

Based on recent CVOTs and guideline updates, the choice of add-on to metformin therapy for patients with T2DM and established CV disease should be a sodium-glucose co-transporter-2 inhibitor or a glucagon-like peptide-1 agonist with proven CV benefit. Additional treatment options for those individuals who require therapy intensification, as well as in patients with T2DM and without established CVD include DPP-4 inhibitors and SUs. Since few head-to-head trials have compared the effects of different oral glucose-lowering agents on CV outcomes in T2DM, with most CVOTs using placebo as a comparator, the CAROLINA trial will provide important information on the comparative CV safety of a commonly prescribed SU and a DPP-4 inhibitor.

All-cause mortality in patients on sulphonylurea monotherapy compared to metformin monotherapy in a nation-wide cohort

BACKGROUND

Type 2 diabetes is associated with increased mortality. There is some data that sulphonylurea therapy may contribute to this.

AIMS

To compare all-cause 3-year mortality of patients on sulphonylurea monotherapy to that of patients on metformin monotherapy after adjusting for potential confounders.

METHODS

We searched the Maltese national electronic database for diabetes treatment in April 2014. This is an electronic database of all treatment that patients are prescribed through the local National Health Service. We identified patients on metformin or sulphonylurea monotherapy and linked this to the national mortality database and the laboratory information system.

RESULTS

There were 25,792 persons who were on treatment for diabetes in April 2014. Of these, 9977 were on metformin monotherapy and 1717 on sulphonylurea monotherapy. This cohort was followed up until April 2017. There were 2518 deaths (9.76%) during this period, giving an average of 32.5 deaths per 1000 persons with diabetes. Logistic regression showed that persons on sulphonylurea monotherapy were 2.03 (95% CI 1.68-2.44, p < .001) times more likely to die within 3 years than persons on metformin monotherapy, after adjusting for age, eGFR and HbA1c. The logistic regression model was statistically significant, p < .001. Additional adjustment for LDL-cholesterol, HDL-cholesterol and urinary albumin-creatinine ratio did not alter the results.

CONCLUSION

Our data shows that sulphonylurea monotherapy is associated with higher all-cause mortality when compared to metformin monotherapy after adjusting for potential confounders.

Documented hypoglycemia is associated with poor short and long term prognosis among patients admitted to general internal medicine departments

AIM

To study the association of documented hypoglycemia with length of stay, 30-day mortality, and 1-year mortality, among patients with and without diabetes admitted to internal medicine units.

METHODS

The electronic medical records of all patients hospitalized in internal medicine departments at E. Wolfson Medical Center, Holon, Israel, between 1/1/2010 and 31/12/2013, were reviewed. Data extracted included all glucose measurements (performed using an institutional blood glucose monitoring system). Patients were considered hypoglycemic if at least one hypoglycemic event was recorded. Regression analysis was used to assess the association between documented hypoglycemia and length of stay, 30-day and one-year mortality. Age, sex, reason for admission, and the Charlson comorbidity index were entered as covariates, and the most conservative model was developed.

RESULTS

The study population included 45,272 patients (mean age 68.9 ± 17.8 years, 49.4% males, 21.0% had diabetes mellitus). The rate of hypoglycemia in the total study population was 7.5% (16.8% among DM patients, 6.0% among patients without diabetes, p < 0.001). Patients with documented hypoglycemia had a longer length of hospital stay (9.3 ± 18.7 vs. 3.1 ± 6.4 days, p < 0.001), as well as higher risk for both 30-day (23.7% vs. 7.0%, p < 0.001) and 1-year mortality (41.6% vs. 15.3%, p < 0.001). Cox regression analysis showed that hypoglycemia significantly increased risk death at one year (HR 2.436, 95% CI 2.298-2.582, p < 0.001) independent of age, sex, the Charlson comorbidity index, DM status and reason for admission.

CONCLUSION

Documented hypoglycemia is associated with prolonged length of hospital stay and increased risk for both 30-day and 1-year mortality, regardless of diabetes mellitus status.

Short-acting insulin analogues versus regular human insulin on postprandial glucose and hypoglycemia in type 1 diabetes mellitus: a systematic review and meta-analysis

INTRODUCTION

Strict glucose control using multiple doses of insulin is the standard treatment for type 1 diabetes mellitus (T1DM), but increased risk of hypoglycemia is a frequent drawback. Regular insulin in multiple doses is important for achieving strict glycemic control for T1DM, but short-acting insulin analogues may be better in reducing hypoglycemia and postprandial glucose levels.

OBJECTIVE

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the effects of short-acting insulin analogues vs regular human insulin on hypoglycemia and postprandial glucose in patients with T1DM.

METHODS

Searches were run on the electronic databases MEDLINE, Cochrane-CENTRAL, EMBASE, ClinicalTrials.gov, LILACS, and DARE for RCTs published until August 2017. To be included in the study, the RCTs had to cover a minimum period of 4 weeks and had to assess the effects of short-acting insulin analogues vs regular human insulin on hypoglycemia and postprandial glucose levels in patients with T1DM. Two independent reviewers extracted the data and assessed the quality of the selected studies. The primary outcomes analyzed were hypoglycemia (total episodes, nocturnal hypoglycemia, and severe hypoglycemia) and postprandial glucose (at all times, after breakfast, after lunch, and after dinner). Glycated hemoglobin (HbA1c) levels and quality of life were considered secondary outcomes. The risk of bias of each RCT was assessed using the Cochrane Collaboration Risk of Bias table, while the quality of evidence for each outcome was assessed using the GRADEpro software. The pooled mean difference in the number of hypoglycemic episodes and postprandial glucose between short-acting insulin analogues vs. regular human insulin was calculated using the random-effects model.

RESULTS

Of the 2897 articles retrieved, 22 (6235 patients) were included. Short-acting insulin analogues were associated with a decrease in total hypoglycemic episodes (risk rate 0.93, 95% CI 0.87-0.99; 6235 patients; I² = 81%), nocturnal hypoglycemia (risk rate 0.55, 95% CI 0.40-0.76, 1995 patients, I² = 84%), and severe hypoglycemia (risk rate 0.68, 95% CI 0.60-0.77; 5945 patients, I² = 0%); and with lower postprandial glucose levels (mean difference/MD - 19.44 mg/dL; 95% CI - 21.49 to - 17.39; 5031 patients, I² = 69%) and lower HbA1c (MD - 0,13%; IC 95% - 0.16 to - 0.10; 5204 patients; I² = 73%) levels.

CONCLUSIONS

Short-acting insulin analogues are superior to regular human insulin in T1DM patients for the following outcomes: total hypoglycemic episodes, nocturnal hypoglycemia, severe hypoglycemia, postprandial glucose, and HbA1c.

Association of albumin and cholesterol levels with incidence of hypoglycaemia in people admitted to general internal medicine units

AIM

To study the association between serum albumin and cholesterol levels at hospital admission and incident hypoglycaemia among people admitted to internal medicine units.

METHODS

In this cross-sectional analysis, we examined the electronic medical records of people hospitalized in internal medicine departments. Data extracted included all glucose measurements as well as serum albumin and cholesterol, which were measured upon admission. A hypoglycaemia event was recorded for a given person if at least one glucose measurement of ≤ 3.9 mmol/l was recorded during the hospital stay. Regression analysis was used to determine which clinical measures predict hypoglycaemia.

RESULTS

During the acquisition period, 45 224 people (mean age 68.9 ± 17.8 years, 49.4% male, 21.1% diabetes mellitus) were discharged from internal medicine units. Hypoglycaemia was documented in 7.5% of these individuals (15.4% of people with diabetes vs. 5.5% of those without; P < 0.001). Logistic regression showed that both serum albumin [odds ratio (OR) 0.908, 95% confidence interval (CI) 0.896-0.919; P < 0.001) and cholesterol (OR 0.938, 95% CI 0.896-0.981; P = 0.005] were significantly associated with incident hypoglycaemia. Results remained significant even after controlling for age, sex, average glucose during hospitalization, length of hospital stay, acute infection upon admission, diabetes status, haemoglobin, white blood cell count and C-reactive levels. A combination of hypoalbuminaemia (< 35 g/l) and hypocholesterolaemia (< 3.37 mmol/l) upon admission greatly increased the risk of incident hypoglycaemia (OR 2.544, 95% CI 2.096-3.088; P < 0.001).

CONCLUSION

Hypoalbuminaemia and hypocholesterolaemia predict incident hypoglycaemia in the hospital setting among people with and without diabetes mellitus.

Real-world prevalence of mild to moderate hypoglycemic episodes in type 2 diabetes in Portugal: Results from the HIPOS-PHARMA study

AIMS

This study aimed to characterize and estimate prevalence and frequency of mild to moderate hypoglycemia and potentially associated factors in a population of type 2 diabetes mellitus (T2DM) patients treated at ambulatory care level.

METHODS

HIPOS-PHARMA was a nationwide observational, cross-sectional, multicenter study conducted in community pharmacies, which surveyed T2DM patients treated for at least 3 months.

RESULTS

Overall, 233 pharmacies recruited 1890 patients (males: 50.6%) with mean 67.1 years. On average, participants reported having diabetes for 11.8 years. A total of 86.9% had at least one chronic illness or complication of diabetes, and 76.8% were usually followed in the primary care setting. Fifty eight percent were treated without a secretagogue or insulin. Overall prevalence of mild to moderate hypoglycemic episodes in the 3 months prior to recruitment was 17.8%. A 3.13% prevalence of severe hypoglycemia was observed in the last 12 months. Results suggested that men and patients on antihyperglycemic therapies excluding secretagogues or insulin were less likely to have mild to moderate hypoglycemic episodes.

CONCLUSIONS

Mild to moderate hypoglycemic episodes were commonly reported, and factors like type of antihyperglycemic therapy, duration of disease and due complications may contribute. Almost half of episodes were not reported. Such factors should be considered in T2DM management.

Association Between Diabetic Microangiopathies and Glycemic Variability Assessed by Continuous Glucose Monitoring

The aim of this retrospective study was to elucidate the association between glucose profile using the continuous glucose monitoring system (CGMS) and microvascular complications in patients with type 2 diabetes mellitus (T2DM). The subjects were 160 inpatients with T2DM. The mean blood glucose (MBG) level, percentage of time in a 24-hour period spent with blood glucose level higher than 180 mg/dl (time at >180 mg/dl), standard deviation (SD), and mean amplitude of glycemic excursions (MAGE) were measured continuously over 48 hours using the CGMS. The primary outcome was the association between microvascular complications and glycemic variability. The secondary outcome was the association between microangiopathies and MBG. The SD and MAGE were not associated with presence of microangiopathies or number of complications. There were also no associations between abnormal vibratory sensation in the bilateral lower extremities, coefficient of variation of the R-R interval (CVRR), retinopathy stage, nephropathy stage, or microalbuminuria. MBG was associated, however, with retinopathy, retinopathy stage, and number of complications. Time at >180 mg/dl correlated with abnormal vibratory sensation in the bilateral lower extremities and presence or stage of retinopathy. MBG and time at >180 mg/dl were not associated with presence or stage of nephropathy. Our findings suggest that broad glycemic variability was not associated with microvascular complications, the number of which increased in patients with a high mean glucose level and long time spent with hyperglycemia. It is important, therefore, to reduce the mean glucose level and time spent with hyperglycemia to prevent future microangiopathies.

Abnormally low Bispectral index and severe hypoglycemia during maintenance of and recovery from general anesthesia in diabetic retinopathy surgery: two case reports

Background

Hypoglycemia is one of the most fatal complications during the perioperative period. General anesthesia or sedation can mask a hypoglycemia-altered mental status. Acute hypoglycemia might result in permanent brain injury. There is no way to detect hypoglycemia during general anesthesia, except for intermittent blood glucose monitoring.

Case presentation

Hypoglycemia is associated with changes in electroencephalogram readings. Here, we report two cases of patients with an abnormally low Bispectral Index (BIS) associated with diabetic retinopathy surgery, one in the recovery stage of general anesthesia and the other in the maintenance of general anesthesia. Hemodynamics were stable. Severe hypoglycemia (1.6 mmol/L and 2.2 mmol/L) was then detected. BIS increased with the correction of severe hypoglycemia.

Conclusions

For diabetic patients, when the intraoperative BIS value is abnormally low, hypoglycemia should be considered. Severe hypoglycemia may be presented in BIS monitoring during general anesthesia.

Risk of a first-ever acute myocardial infarction and all-cause mortality with sulphonylurea treatment: A population-based cohort study

We investigated the association between the current use of individual sulphonylureas and the risk of a first-ever acute myocardial infarction (AMI) and all-cause mortality, in a population-based cohort study, using primary care data from the Clinical Practice Research Datalink database (2004-2012). New users (N = 121 869), aged ≥18 years, with at least one prescription for a non-insulin antidiabetic agent were included. The first prescription defined start of follow-up. Time-dependent Cox proportional hazard models were used to estimate the risk of a first-ever AMI and all-cause mortality associated with the use of individual sulphonylureas, and other non-insulin glucose-lowering drugs. No differences in risk of a first-ever AMI (adjusted hazard ratio [HR] 1.02, 95% confidence interval [CI] 0.70-1.50) or all-cause mortality (adjusted HR 0.97, 95% CI 0.80-1.17) were observed when comparing gliclazide use with non-gliclazide sulphonylurea use. Similar results were found for each individual sulphonylurea. As evidence is accumulating that gliclazide is no safer than other sulphonylureas, current guidelines suggesting superiority should be carefully evaluated.

Hypoglycaemia in the over 75s: Understanding the predisposing factors in type 2 diabetes (T2DM)

INTRODUCTION

Hypoglycaemia has been recognised as a problem in the treatment for type 2 diabetes. Here we describe how levels of HbA1C and treatment with a sulphonylurea or insulin relate to risk of significant hypoglycaemia.

METHODS

Incident hypoglycaemia as recorded for the previous 10 years was determined from the GP records for patients with T2DM aged 75 years or more.

RESULTS

The anonymised GP records of 5974 T2DM patients (2934 men and 3040 women) aged 75 years or more were analysed. Mean age of the men was 81.0 (95% confidence interval (CI) 80.9-81.2) years and of the women was 82.2 (95% CI 82.0-82.4) years. Hypoglycaemic events of significance were recorded in 4.9% of men and 5.1% of women. The prevalence of hypoglycaemia was higher in those with a higher concurrent HbA1C. HbA1C for those people with a recorded significant hypoglycaemic attack(s) was 57.9 (95% CI 56.4-59.4) mmol/mol compared to those with no history of hypoglycaemic episodes at 51.6 (95% CI 51.3-52.0) mmol/mol (p<0.002). Even for those on sulphonylurea and/or insulin treatment, hypoglycaemia prevalence increased with HbA1C: for patients with an HbA1C of <48mmol/mol, age and gender adjusted hypoglycaemia prevalence was 11.1%, for HbA1C of 48-57mmol/mol, prevalence 9.9%, for HbA1C 58-67mmol/mol prevalence, 13.2% and for HbA1C 68mmol/mol or more, prevalence of hypoglycaemia was 16.1%. There was a slight fall in HbA1C by age (normalised β -0.069, p<0.001) and no difference by level of social disadvantage. Treatment with a sulphonylurea or insulin very significantly increased the likelihood of a hypoglycaemic episode: odds ratio (OR) 8.94 (95% CI 6.45-12.42), p<0.001, independent of age, BMI, Townsend index and gender.

CONCLUSION

Prevalence of hypoglycaemia was greater in those individuals with higher HbA1C and in those on sulphonylurea/insulin treatment. Our findings suggest that it is variance in blood glucose rather than overall lower blood glucose levels that predisposes older people to hypoglycaemia.

Increased Risk of Severe Hypoglycemic Events Before and After Cardiovascular Outcomes in TECOS Suggests an At-Risk Type 2 Diabetes Frail Patient Phenotype

OBJECTIVE

Severe hypoglycemic events (SHEs) in type 2 diabetes are associated with subsequent cardiovascular (CV) event risk. We examined whether CV events were associated with subsequent SHE risk.

RESEARCH DESIGN AND METHODS

Time-dependent associations between SHEs and a composite CV end point (fatal/nonfatal myocardial infarction or stroke, hospitalization for unstable angina, hospitalization for heart failure [hHF]) were examined post hoc in 14,671 TECOS (Trial Evaluating Cardiovascular Outcomes With Sitagliptin) participants with type 2 diabetes and CV disease followed for a median of 3.0 years.

RESULTS

SHEs were uncommon and unassociated with sitagliptin therapy (N = 160 [2.2%], 0.78/100 patient-years vs. N = 143 [1.9%], 0.70/100 patient-years for placebo; hazard ratio [HR] 1.12 [95% CI 0.89, 1.40], P = 0.33). Patients with (versus without) SHEs were older with longer diabetes duration, lower body weight, and lower estimated glomerular filtration rate; were more frequently women, nonwhite, and insulin treated; and more often had microalbuminuria or macroalbuminuria. Analyses adjusted for clinical factors showed SHEs were associated with increased risk of the primary composite CV end point (1.55 [1.06, 2.28], P = 0.025), all-cause death (1.83 [1.22, 2.75], P = 0.004), and CV death (1.72 [1.02, 2.87], P = 0.040). Conversely, nonfatal myocardial infarction (3.02 [1.83, 4.96], P < 0.001), nonfatal stroke (2.77 [1.36, 5.63], P = 0.005), and hHF (3.68 [2.13, 6.36], P < 0.001) were associated with increased risk of SHEs. Fully adjusted models showed no association between SHEs and subsequent CV or hHF events, but the association between CV events and subsequent SHEs remained robust.

CONCLUSIONS

These findings, showing greater risk of SHEs after CV events and greater risk of CV events after SHEs, suggest a common at-risk type 2 diabetes frail patient phenotype.

Real-life glycemic control in patients with type 2 diabetes treated with insulin therapy: A prospective, longitudinal cohort study (Diabetes Distress and Care Registry at Tenri [DDCRT 9])

AIMS/INTRODUCTION

We investigated the association between four insulin regimens, and increase in glycated hemoglobin (HbA1c) and insulin dose in a real-life clinical setting because there are no data about them among insulin regimens.

MATERIALS AND METHODS

Participants included 757 patients with type 2 diabetes having been treated with insulin therapy for more than 1 year. The four insulin regimens were regimen 1 (long-acting insulin, once daily), regimen 2 (biphasic insulin, twice daily), regimen 3 (biphasic insulin, three times daily) and regimen 4 (basal-bolus therapy). Main outcomes were increases in HbA1c levels >0.5% and increases in daily insulin units after 1 year. We carried out multivariable analyses to examine differences in glycemic control and insulin dose with adjustment for possible confounders.

RESULTS

Mean HbA1c level and duration of insulin therapy were 7.8% and 11.3 years, respectively. HbA1c levels increased by >0.5% at follow up in 22.8, 24.9, 20.7, and 29.3% of participants using regimen 1, 2, 3 and 4, respectively, with no significant differences between groups. Daily insulin doses increased in 62.3, 68.8, 65.3 and 38.6% of patients, respectively (P < 0.001). Multivariable regression analysis showed that patients who received regimen 4 had significantly lower odds of requiring future insulin dose increases than those who had received regimen 2 (adjusted odds ratio 0.24, 95% confidence interval 0.14-0.41; P < 0.001).

CONCLUSIONS

Many patients receiving insulin therapy showed increases in HbA1c levels and insulin doses 1 year later. The smallest increase in insulin dose was observed in the basal-bolus therapy group compared with other regimens.

Biomedical Informatics Approaches to Identifying Drug-Drug Interactions: Application to Insulin Secretagogues

BACKGROUND

Drug-drug interactions with insulin secretagogues are associated with increased risk of serious hypoglycemia in patients with type 2 diabetes. We aimed to systematically screen for drugs that interact with the five most commonly used secretagogues-glipizide, glyburide, glimepiride, repaglinide, and nateglinide-to cause serious hypoglycemia.

METHODS

We screened 400 drugs frequently coprescribed with the secretagogues as candidate interacting precipitants. We first predicted the drug-drug interaction potential based on the pharmacokinetics of each secretagogue-precipitant pair. We then performed pharmacoepidemiologic screening for each secretagogue of interest, and for metformin as a negative control, using an administrative claims database and the self-controlled case series design. The overall rate ratios (RRs) and those for four predefined risk periods were estimated using Poisson regression. The RRs were adjusted for multiple estimation using semi-Bayes method, and then adjusted for metformin results to distinguish native effects of the precipitant from a drug-drug interaction.

RESULTS

We predicted 34 pharmacokinetic drug-drug interactions with the secretagogues, nine moderate and 25 weak. There were 140 and 61 secretagogue-precipitant pairs associated with increased rates of serious hypoglycemia before and after the metformin adjustment, respectively. The results from pharmacokinetic prediction correlated poorly with those from pharmacoepidemiologic screening.

CONCLUSIONS

The self-controlled case series design has the potential to be widely applicable to screening for drug-drug interactions that lead to adverse outcomes identifiable in healthcare databases. Coupling pharmacokinetic prediction with pharmacoepidemiologic screening did not notably improve the ability to identify drug-drug interactions in this case.

Relationship of Hyperglycaemia, Hypoglycaemia, and Glucose Variability to Atherosclerotic Disease in Type 2 Diabetes

OBJECTIVE

Type 2 diabetes mellitus (T2DM) is known to be associated with increased cardiovascular risk. The aim of this study was therefore to investigate the independent effects of hyperglycaemia, hypoglycaemia, and glucose variability on microvascular and macrovascular disease in T2DM.

METHODS

Subjects with T2DM of <10 years duration and on stable antiglycaemic treatment underwent carotid intima-media thickness (CIMT), ankle-brachial index (ABI), albumin-creatinine ratio (ACR), and HbA_1c measurement, as well as 72-hour continuous glucose monitoring. Macrovascular disease was defined as one or more of the following: history of ischaemic heart disease (IHD), cerebrovascular accident (CVA), ABI < 0.9, or abnormal CIMT.

RESULTS

The study population comprised 121 subjects with T2DM (89 males : 32 females). The mean age was 62.6 years, and the mean DM duration was 3.7 years. Macrovascular disease was present in 71 patients (58.7%). In multivariate logistic regression analysis, body surface area (BSA) (OR 18.88 (95% CI 2.20-156.69), p = 0.006) and duration of blood glucose (BG) < 3.9 mmol/L (OR 1.12 (95% CI 1.014-1.228), p = 0.024) were independent predictors of macrovascular disease. BSA (OR 12.6 (95% CI 1.70-93.54), p = 0.013) and duration of BG < 3.9 mmol/L (OR 1.09 (95% CI 1.003-1.187), p = 0.041) were independent predictors of abnormal CIMT. Area under the curve for BG > 7.8 mmol/L (β = 15.83, p = 0.005) was the sole independent predictor of albuminuria in generalised linear regression.

CONCLUSIONS

This study demonstrates that hypoglycaemia is associated with the occurrence of atherosclerotic disease while hyperglycaemia is associated with microvascular disease in a Caucasian population with T2DM of recent duration.

Hypoglycemia Reduction Strategies in the ICU

PURPOSE OF REVIEW

We reviewed the strategies associated with hypoglycemia risk reduction among critically ill non-pregnant adult patients.

RECENT FINDINGS

Hypoglycemia in the ICU has been associated with increased mortality in a number of studies. Insulin dosing and glucose monitoring rules, response to impending hypoglycemia, use of computerization, and attention to modifiable factors extrinsic to insulin algorithms may affect the risk for hypoglycemia. Recurring use of intravenous (IV) bolus doses of insulin in insulin-resistant cases may reduce reliance upon higher IV infusion rates. In order to reduce the risk for hypoglycemia in the ICU, caregivers should define responses to interruption of continuous carbohydrate exposure, incorporate transitioning strategies upon initiation and interruption of IV insulin, define modifications of antihyperglycemic therapy in the presence of worsening renal function or chronic kidney disease, and anticipate the effects traceable to other medications and substances. Institutional and system-wide quality improvement efforts should assign priority to hypoglycemia prevention.

Impact of renal function on the underlying pathophysiology of coronary plaque composition in patients with type 2 diabetes mellitus

BACKGROUND

Both the progression of diabetic kidney disease and increased glycemic variability play important roles in the pathogenesis of coronary plaque formation via inflammatory pathways in patients with type 2 diabetes mellitus (T2DM). Therefore we evaluated the role of renal function in the contributory effects of blood glucose fluctuations and blood levels of inflammatory cytokine concentrations on the tissue characteristics of coronary plaques in patients with T2DM.

METHODS

We prospectively enrolled 71 T2DM patients (mean age: 68 ± 9, male 79%) with 153 coronary artery lesions. Patients were divided into 2 groups according to their estimated glomerular filtration rate (eGFR) levels: Group 1 (≥ 60 mL/min/1.73 m², n = 40) and Group 2 (< 60 mL/min/1.73 m², n = 31). All patients underwent continuous glucose monitoring (CGM) for 120 h and the mean amplitude of glycemic excursions (MAGE) was calculated. Serum tumor necrosis factor (TNF)-α was also measured. In addition, gray-scale coronary intravascular ultrasound (IVUS) and iMap-IVUS were performed in the coronary lesions with < 50% luminal reduction.

RESULTS

In Group 1, MAGE correlated with percent lipidic volume (%LV) (r = 0.477, p = 0.002). In this group, stepwise multivariate linear regression analyses showed that only MAGE was independently associated with %LV (β = 0.477, p = 0.002). In contrast, in Group 2, only serum TNF-α correlated with percent fibrotic volume (%FV) (r = - 0.471, p = 0.007), %LV (r = 0.496, p = 0.005) and percent necrotic volume (%NV) (r = 0.426, p = 0.017). In this group, stepwise multivariate linear regression analyses showed that only serum TNF-α was independently associated with each tissue characteristic (%FV β = - 0.471 and p = 0.007, %LV β = 0.496 and p = 0.005, %NV: β = 0.426 and p = 0.017).

CONCLUSIONS

In T2DM patients, the tissue characteristics of coronary plaques were associated with MAGE in patients with eGFR ≥ 60 mL/min/1.73 m² and with serum TNF-α in those with eGFR < 60 mL/min/1.73 m².

Real-Time Continuous Glucose Monitoring Facilitates Feelings of Safety in Older Adults With Type 1 Diabetes: A Qualitative Study

BACKGROUND

Older adults with long-standing type 1 diabetes (T1D) have a higher risk for hypoglycemia and hypoglycemia unawareness. Hypoglycemia can be dangerous, even fatal. Real-time continuous glucose monitoring (RT-CGM) effectively supports diabetes management and well-being in adult and pediatric populations. Little is known about older adults and RT-CGM use. The purpose of this study was to identify why RT-CGM was important for diabetes management in individuals with T1D 65 years of age.

METHODS

A convenience sample of older adults with T1D participated in one of two online surveys about RT-CGM. Categorical data were analyzed using descriptive statistics. A qualitative content analysis was conducted for open-ended responses.

RESULTS

Participants (N = 22) included in this study were those using RT-CGM (n = 11) and those who were not using RT-CGM, but desired to do so (n = 11). Those using RT-CGM were less likely to experience severe hypoglycemia ( P = .02) or hypoglycemia resulting in a fall or inability to operate a motor vehicle ( P = .01) Three major themes were identified: (1) RT-CGM facilitates feelings of safety by preventing hypoglycemia, (2) RT-CGM improves well-being, and (3) access is a barrier to RT-CGM use.

CONCLUSIONS

RT-CGM improves safety and well-being in older adults with T1D by preventing hypoglycemia and associated injury and worry. Older adults without access to RT-CGM experience more severe hypoglycemia events that negatively affect their safety and well-being. Improving access to RT-CGM in older adults is critical to improving health and safety, and demands more attention from stakeholders in diabetes care.

Glucose targets for preventing diabetic kidney disease and its progression

BACKGROUND

Diabetes is the leading cause of end-stage kidney disease (ESKD) around the world. Blood pressure lowering and glucose control are used to reduce diabetes-associated disability including kidney failure. However there is a lack of an overall evidence summary of the optimal target range for blood glucose control to prevent kidney failure.

OBJECTIVES

To evaluate the benefits and harms of intensive (HbA1c < 7% or fasting glucose levels < 120 mg/dL versus standard glycaemic control (HbA1c ≥ 7% or fasting glucose levels ≥ 120 mg/dL for preventing the onset and progression of kidney disease among adults with diabetes.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register up to 31 March 2017 through contact with the Information Specialist using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE, and EMBASE; handsearching conference proceedings; and searching the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials evaluating glucose-lowering interventions in which people (aged 14 year or older) with type 1 or 2 diabetes with and without kidney disease were randomly allocated to tight glucose control or less stringent blood glucose targets.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility and risks of bias, extracted data and checked the processes for accuracy. Outcomes were mortality, cardiovascular complications, doubling of serum creatinine (SCr), ESKD and proteinuria. Confidence in the evidence was assessing using GRADE. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes.

MAIN RESULTS

Fourteen studies involving 29,319 people with diabetes were included and 11 studies involving 29,141 people were included in our meta-analyses. Treatment duration was 56.7 months on average (range 6 months to 10 years). Studies included people with a range of kidney function. Incomplete reporting of key methodological details resulted in uncertain risks of bias in many studies. Using GRADE assessment, we had moderate confidence in the effects of glucose lowering strategies on ESKD, all-cause mortality, myocardial infarction, and progressive protein leakage by kidney disease and low or very low confidence in effects of treatment on death related to cardiovascular complications and doubling of serum creatinine (SCr).For the primary outcomes, tight glycaemic control may make little or no difference to doubling of SCr compared with standard control (4 studies, 26,874 participants: RR 0.84, 95% CI 0.64 to 1.11; I2= 73%, low certainty evidence), development of ESKD (4 studies, 23,332 participants: RR 0.62, 95% CI 0.34 to 1.12; I2= 52%; low certainty evidence), all-cause mortality (9 studies, 29,094 participants: RR 0.99, 95% CI 0.86 to 1.13; I2= 50%; moderate certainty evidence), cardiovascular mortality (6 studies, 23,673 participants: RR 1.19, 95% CI 0.73 to 1.92; I2= 85%; low certainty evidence), or sudden death (4 studies, 5913 participants: RR 0.82, 95% CI 0.26 to 2.57; I2= 85%; very low certainty evidence). People who received treatment to achieve tighter glycaemic control probably experienced lower risks of non-fatal myocardial infarction (5 studies, 25,596 participants: RR 0.82, 95% CI 0.67 to 0.99; I2= 46%, moderate certainty evidence), onset of microalbuminuria (4 studies, 19,846 participants: RR 0.82, 95% CI 0.71 to 0.93; I2= 61%, moderate certainty evidence), and progression of microalbuminuria (5 studies, 13,266 participants: RR 0.59, 95% CI 0.38 to 0.93; I2= 75%, moderate certainty evidence). In absolute terms, tight versus standard glucose control treatment in 1,000 adults would lead to between zero and two people avoiding non-fatal myocardial infarction, while seven adults would avoid experiencing new-onset albuminuria and two would avoid worsening albuminuria.

AUTHORS' CONCLUSIONS

This review suggests that people who receive intensive glycaemic control for treatment of diabetes had comparable risks of kidney failure, death and major cardiovascular events as people who received less stringent blood glucose control, while experiencing small clinical benefits on the onset and progression of microalbuminuria and myocardial infarction. The adverse effects of glycaemic management are uncertain. Based on absolute treatment effects, the clinical impact of targeting an HbA1c < 7% or blood glucose < 6.6 mmol/L is unclear and the potential harms of this treatment approach are largely unmeasured.

Cardiac Effects of Sulfonylurea-Related Hypoglycemia

OBJECTIVE

To determine the effect of sulfonylurea-related hypoglycemia on cardiac repolarization and ectopy in the setting of well-controlled type 2 diabetes.

RESEARCH DESIGN AND METHODS

Thirty subjects with sulfonylurea-treated type 2 diabetes underwent 48 h of concurrent continuous glucose monitoring and ambulatory electrocardiography. Ventricular repolarization (QTc) and QT dynamicity were analyzed during periods of hypoglycemia (<3.5 mmol/L for >20 min) and compared with periods of euglycemia and hyperglycemia combined. Cardiac ectopy rates during hypoglycemia were compared with ectopy rates when blood glucose was 4-10 mmol/L.

RESULTS

Mean HbA_1c was 6.9% (52 mmol/mol). Hypoglycemia was detected in 9 of 30 subjects (30%); episodes were typically nocturnal (67%) and asymptomatic (73%). Hypoglycemia-associated QTc prolongation was seen in five of nine subjects with a large variation in individual response. Higher QT dynamicity, a poor prognostic factor in cardiac disease, was seen in subjects who experienced hypoglycemia compared with subjects who did not (0.193 vs. 0.159 for the nocturnal period; P = 0.01). This finding persisted after the hypoglycemic event. The rates of ventricular and supraventricular ectopy demonstrated a nonsignificant trend toward an increase during hypoglycemia (median rate ratio 1.58 and 1.33, respectively). Similar, nonsignificant results were observed in a separate insulin-treated cohort.

CONCLUSIONS

Hypoglycemia, often unrecognized, is a frequent finding in well-controlled sulfonylurea-treated type 2 diabetes. It is associated with the novel finding of increased QT dynamicity and QTc prolongation in some individuals. Our findings suggest sulfonylurea-related hypoglycemia can have detrimental cardiovascular sequelae. Similar effects are also seen in the setting of insulin therapy.

Incidence of and risk factors for hospitalisations due to vascular complications: A population-based type 1 diabetes cohort (n=1316) followed into early adulthood

AIM

To determine the incidence of hospitalisations and risk factors for vascular complications experienced during early adulthood in patients with childhood onset type 1 diabetes.

METHODS

A population-based childhood onset type 1 diabetes cohort was identified from a statewide register (1992-2012). Data linkage was used to identify a matched comparison cohort. Hospital admissions data were extracted to follow up both cohorts into early adulthood (1975-2012).

RESULTS

The type 1 diabetes cohort (n=1316) had a mean age of diagnosis of 9.5years, 49.5% were women and mean age at the end of follow-up was 26.3years (range 18-38). Within the type 1 diabetes cohort 32 (2.4%) were hospitalised with a vascular complication during early adulthood. Poor glycaemic control during paediatric management was associated with a significant increase in risk for ophthalmic complication with 19.4% (n=12/62) of those with a mean HbA1c >12% (108mmol/mol) diagnosed compared to 0.72% (n=5/696) of those with mean HbA1c <9% (75mmol/mol), adjusted hazard ratio 8.4 (95% CI 2.0, 34.7).

CONCLUSION

Severe vascular complications requiring hospital admission continue to be observed during early adulthood. Both women and those with poor glycaemic control are at increased risk of requiring a hospital admission for these complications during early adulthood.

Cerebral ischemic damage in diabetes: an inflammatory perspective

Stroke is one of the leading causes of death worldwide. A strong inflammatory response characterized by activation and release of cytokines, chemokines, adhesion molecules, and proteolytic enzymes contributes to brain damage following stroke. Stroke outcomes are worse among diabetics, resulting in increased mortality and disabilities. Diabetes involves chronic inflammation manifested by reactive oxygen species generation, expression of proinflammatory cytokines, and activation/expression of other inflammatory mediators. It appears that increased proinflammatory processes due to diabetes are further accelerated after cerebral ischemia, leading to increased ischemic damage. Hypoglycemia is an intrinsic side effect owing to glucose-lowering therapy in diabetics, and is known to induce proinflammatory changes as well as exacerbate cerebral damage in experimental stroke. Here, we present a review of available literature on the contribution of neuroinflammation to increased cerebral ischemic damage in diabetics. We also describe the role of hypoglycemia in neuroinflammation and cerebral ischemic damage in diabetics. Understanding the role of neuroinflammatory mechanisms in worsening stroke outcome in diabetics may help limit ischemic brain injury and improve clinical outcomes.

QT prolongation caused by insulin-induced hypoglycaemia - An interventional study in 119 individuals

AIMS

Hypoglycaemia is associated with increased risk of cardiovascular events and mortality in patients with diabetes, but the extent and mechanisms of this link are ill defined. We here prospectively studied cardiac repolarization abnormalities during insulin-induced hypoglycaemia in humans.

METHODS

119 individuals (69 males, age 47.5±13.4years, range 18-82years) were assessed during hypoglycaemia after the injection of 0.1-0.25units/kg human insulin. Corrected QT intervals (QTc) and QT dispersion (QTd) were calculated from serially recorded twelve lead electrocardiograms, and plasma glucose and other endocrine markers were studied.

RESULTS

QTc increased from 415.1±21.9ms (mean±standard deviation) at baseline to 444.9±26.5ms during hypoglycaemia (plasma glucose nadir, 1.6±0.5mmol/L, p=0.001), accompanied by an increase of QTd from 45.0±22.7ms to 64.1±40.0ms (p<0.001). Hypoglycaemia-induced abnormal QTc prolongation (defined as ⩾460ms in females and ⩾450ms in males) occurred in 17% (9/54) of females and 26% (17/65) of males. 97 of 119 of individuals (82%) developed transient hypokalaemia (K⁺ ⩽3.6mmol/L), and plasma epinephrine increased from 220.4±169.5pmol/L at baseline to 2945.6±2421.4pmol/L during hypoglycaemia. Baseline QTc, but not age or gender, was a significant predictor of hypoglycaemia-induced QTc prolongation (p=0.001).

CONCLUSIONS

Insulin-induced hypoglycaemia frequently causes abnormal QT prolongation and is associated with hypokalaemia and sympathoadrenal activation, thereby increasing the potential risk for ventricular arrhythmias, particularly in individuals with pre-existing high normal QTc.

Comparative effects of acute hypoglycemia and hyperglycemia on pro-atherothrombotic biomarkers and endothelial function in non-diabetic humans

BACKGROUND

The comparative effects of acute moderate hyperglycemia and hypoglycemia on in vivo endothelial function together with pro-inflammatory and pro-atherothrombotic responses in healthy individuals have not been determined.

METHODS

To investigate this question, 45 healthy subjects were compared during glucose clamp studies consisting of euinsulinemic hyperglycemia and hyperinsulinemic hyperglycemia (plasma glucose 11.1mmol/L, both with pancreatic clamps) and hyperinsulinemic euglycemia and hyperinsulinemic hypoglycemia (plasma glucose 5.1 and 2.9mmol/L, respectively). Two-dimensional Doppler ultrasound was used to determine brachial artery endothelial function.

RESULTS

Insulin levels during euinsulinemia hyperglycemia were 194±23 and (850±49-988±114) pmol/L during all hyperinsulinemic protocols. Responses of VCAM-1, ICAM-1, E-selectin, P-selectin, PAI-1, and IL-6 were increased (p<0.05-0.0001) during euinsulinemic hyperglycemia or hypoglycemia as compared to hyperinsulinemic euglycemia or hyperinsulinemic hyperglycemia. PAI-1 was increased (p<0.04) during hypoglycemia as compared to euinsulinemic hyperglycemia, and TNF-α responses were also increased during hypoglycemia as compared to hyperinsulinemic euglycemia or hyperinsulinemic hyperglycemia (p<0.05). In vivo endothelial function was similarly blunted by acute moderate hyperglycemia or hypoglycemia.

CONCLUSION

In summary, acute moderate hypoglycemia and euinsulinemic hyperglycemia can result in similar endothelial dysfunction and pro-atherothrombotic responses. Fibrinolytic balance was reduced by a greater extent by hypoglycemia as compared to moderate hyperglycemia. Acutely, hyperinsulinemia can prevent the acute pro-atherothrombotic and pro-inflammatory effects of moderate hyperglycemia but not hypoglycemia.

Hypoglycaemia when adding sulphonylurea to metformin: a systematic review and network meta-analysis

AIMS

The risk of hypoglycaemia may differ among sulphonylureas (SUs), but evidence from head-to-head comparisons is sparse. Performing a network meta-analysis to use indirect evidence from randomized controlled trials (RCTs), we compared the relative risk of hypoglycaemia with newer generation SUs when added to metformin.

METHODS

A systematic review identified RCTs lasting 12-52 weeks and evaluating SUs added to inadequate metformin monotherapy (≥1000 mg/day) in type 2 diabetes. Adding RCTs investigating the active comparators from the identified SU trials, we established a coherent network. Hypoglycaemia of any severity was the primary end point.

RESULTS

Thirteen trials of SUs and 14 of oral non-SU antihyperglycaemic agents (16 260 patients) were included. All reported hypoglycaemia only as adverse events. Producing comparable reductions in HbA_1C of -0.66 to -0.84% (-7 to -9 mmol/mol), the risk of hypoglycaemia was lowest with gliclazide compared to glipizide (OR 0.22, CrI: 0.05 to 0.96), glimepiride (OR 0.40, CrI: 0.13 to 1.27), and glibenclamide (OR 0.21, CrI: 0.03 to 1.48). A major limitation is varying definitions of hypoglycaemia across studies.

CONCLUSIONS

When added to metformin, gliclazide was associated with the lowest risk of hypoglycaemia between the newer generation SUs. Clinicians should consider the risk of hypoglycaemia agent-specific when selecting an SU agent.

Biomarkers associated with severe hypoglycaemia and death in ACCORD

AIMS AND HYPOTHESIS

In patients with Type 2 diabetes, intensive glycaemic control is associated with hypoglycaemia and possibly increased mortality. However, no blood biomarkers exist to predict these outcomes. Using participants from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study, we hypothesized that insulin deficiency and islet autoantibodies in patients with clinically diagnosed Type 2 diabetes would be associated with severe hypoglycaemia and death.

METHODS

A nested case-control study design was used. A case (n = 86) was a participant who died with at least one episode of severe hypoglycaemia, defined as hypoglycaemia requiring assistance, at any point during ACCORD follow-up. A control (n = 344) was a participant who did not die and did not have severe hypoglycaemia during follow-up. Each case was matched to four controls (glycaemic intervention arm, race, age and BMI). Baseline insulin deficiency (fasting C-peptide ≤ 0.15 nmol/l) and islet autoantibodies [glutamic acid decarboxylase (GAD), tyrosine phosphatase-related islet antigen 2 (IA2), insulin (IAA) and zinc transporter (ZnT8)] were measured. Conditional logistic regression with and without adjustment for age, BMI and diabetes duration was used.

RESULTS

Death during ACCORD in those who experienced at least one episode of severe hypoglycaemia was associated with insulin deficiency [OR 4.8 (2.1, 11.1): P < 0.0001], GAD antibodies [OR 2.3 (1.1, 5.1): P = 0.04], the presence of IAA or baseline insulin use [OR 6.1 (3.5,10.7): P < 0.0001], which remained significant after adjusting for age, BMI, and diabetes duration. There was no significant association with IA2 or ZnT8 antibodies.

CONCLUSIONS

In patients with Type 2 diabetes, C-peptide or GAD antibodies may serve as blood biomarkers predicting higher odds of subsequent severe hypoglycaemia and death. (Clinical Trial Registry No: NCT00000620, www.clinicaltrials.gov for original ACCORD study).

Hypoglycemia and Cardiovascular Risk: Is There a Major Link?

Severe hypoglycemia is recognized to be one of the strongest predictors of macrovascular events, adverse clinical outcomes, and mortality in patients with type 2 diabetes. However, it is uncertain whether a direct pathophysiological link exists or whether hypoglycemia is primarily a marker of vulnerability to these events. Large clinical trials have reported an increased hazard ratio for all-cause mortality and cardiovascular events in patients with type 2 diabetes and severe hypoglycemia, but such an association has not been demonstrated in prospective trials of people with type 1 diabetes. Several cardiovascular effects occur during hypoglycemia either as a result of low blood glucose levels per se or through activation of the sympathoadrenal response: hemodynamic changes with an increase in cardiac work load and potential attenuation of myocardial perfusion, electrophysiological changes that may be arrhythmogenic, induction of a prothrombotic state, and release of inflammatory markers. Although the potential for a causal relationship has been demonstrated in mechanistic studies, the evidence from large prospective studies that hypoglycemia is a major causal contributor to cardiovascular events is limited to date. Other preexisting cardiovascular risk factors in addition to hypoglycemia may be the major link to the final cardiovascular event, but a low blood glucose level can trigger these events in patients with a high cardiovascular risk.

Diurnal glycemic fluctuation is associated with severity of coronary artery disease in prediabetic patients: Possible role of nitrotyrosine and glyceraldehyde-derived advanced glycation end products

BACKGROUND

Glucose fluctuation (GF) is a risk factor for coronary artery disease (CAD). However, it remains unknown whether specific indices of GF are risk factors for CAD. Therefore, we evaluated the relationship between GF, as determined by a continuous glucose monitoring system (CGMS) or the glucose level at 2h after a 75-g oral glucose tolerance test (75g OGTT 120), and the severity of CAD in prediabetic patients. We also evaluated whether nitrotyrosine (NT) and glyceraldehyde-derived advanced glycation end-products (Glycer-AGE) were induced by GF.

METHODS

Twenty-eight prediabetic patients underwent coronary angiography (CAG), and the Gensini score and the SYNTAX score were evaluated as the severity of CAD, while the mean amplitude of glycemic excursions (MAGE) by CGMS and 75g OGTT 120 were evaluated. Serum NT and Glycer-AGE were measured.

RESULTS

The MAGE was closely associated with the Gensini score (r=0.742, p<0.001) and the SYNTAX score (r=0.776, p<0.001), respectively. The 75g OGTT 120 was not associated with the Gensini score (r=0.36, p=0.06), but it was significantly associated with the SYNTAX score (r=0.413, p=0.036). Multiple linear regression analysis showed that the MAGE was the only independent determinant for the severity of CAD. The levels of NT and Glycer-AGE were significantly higher in the high MAGE group than in the low MAGE group.

CONCLUSIONS

Diurnal GF is associated with the severity of CAD, even in prediabetic patients. GF, NT, and Glycer-AGE may play a pathological role in the progression of CAD.

Cardiovascular effects of anti-diabetes drugs

INTRODUCTION

Cardiovascular disease remains the major contributor to morbidity and mortality in diabetes. From the need to reduce cardiovascular risk in diabetes and to ensure that such risk is not exacerbated by drug treatments, governmental regulators and drug manufacturers have focused on clinical trials evaluating cardiovascular outcomes.

AREAS COVERED

Findings from mechanistic and clinical trials of biguanides, sulfonylureas, thiazolidinediones, dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide-1 (GLP-1) receptor agonists, and sodium-glucose co-transporter 2 (SGLT-2) inhibitors will be reviewed. These drug classes will be compared within the context of available cardiovascular outcomes data. Clinical implications of new study regulations will be examined.

EXPERT OPINION

Recent cardiovascular studies provide a more comprehensive evaluation of specific anti-diabetes therapy in individuals with high cardiovascular risk. Long-term effects of anti-hyperglycemic agents in patients with lower cardiovascular risk are still speculative. Historical data supports continued use of metformin as a first-line agent. DPP-4 inhibitors and GLP-1 receptor agonists appear to have neutral effects on cardiovascular outcomes. The significantly decreased cardiovascular risk associated with empagliflozin SGLT-2 inhibitor therapy is impressive and may change how practitioners prescribe add-on therapy to metformin.

Glucose levels as a prognostic marker in patients with ST-segment elevation myocardial infarction: a case-control study

BACKGROUND

Patients with myocardial infarction (MI) have a high mortality. Therefore, new risk markers and predictors of an adverse outcome for MI are required. The role of hyperglycemia in the development of cardiovascular complications in MI patients is still unclear.

METHODS

A total of 529 consecutive patients with the diagnosis of ST-segment elevation acute coronary syndrome within 24 h of the onset of symptoms were included in the study. All of the patients underwent blood glucose measurement at admission to hospital. The glycemic profile, including measurement of blood glucose levels early in the night and in the morning (3 a.m. and 5 a.m.), was assessed in 77 patients with diabetes on days 6-10 of the course of MI to monitor the efficiency of blood glucose-lowering therapy and to detect hypoglycemic episodes.

RESULTS

In-hospital mortality showed relationship between the level of blood glucose on admission and in-hospital mortality in patients with MI with ST-segment elevation in combination with diabetes mellitus. There was a direct linear relationship between blood glucose levels and in-hospital mortality in patients without diabetes.

CONCLUSION

Episodes of hypoglycemia recorded in MI patients with diabetes in the hospital stage of treatment do not determine the prognosis, but enable identification of patients with an unfavorable course in the postinfarction period.

Hypoglycemia and risk of vascular events and mortality: a systematic review and meta-analysis

AIMS

Hypoglycemia has been associated with adverse outcomes in patients with diabetes and critical illness. However, such associations in these populations have not been systematically examined.

METHODS

We conducted a systematic review and meta-analysis of longitudinal follow-up cohort studies to investigate the associations between hypoglycemia and various adverse outcomes.

RESULTS

After removing duplicates and critically appraising all screened citations, a total of 19 eligible studies were included. As demonstrated by random-effects meta-analysis, hypoglycemia was strongly associated with a higher risk of adverse events (HR 1.90, 95 % CI 1.63-2.20; P < 0.001). Comparable risk ratios were shown in prespecified stratified analyses investigating above association for different study endpoints, in patients with or without critical illness, in patients with and without diabetes (from 1.47 to 3.31; p for interaction or heterogeneity >0.1). Additionally, a dose-dependent relationship between the severity of hypoglycemia and adverse vascular events and mortality (HR for mild hypoglycemia: 1.68, 95 % CI 1.25-2.26; P < 0.001 and HR for severe hypoglycemia: 2.33, 95 % CI 2.07-2.61; P < 0.001; p for trend 0.02) was observed. Suggested by a bias analysis, the above observations were unlikely to have resulted from unmeasured confounding parameters.

CONCLUSIONS

This is the first study demonstrating that hypoglycemia was associated with comparable risk ratios in different study populations and various study endpoints, and a trend of a dose-dependent relationship between hypoglycemia severity and adverse events. The findings of this systematic review support the speculation that hypoglycemia is a risk factor for adverse vascular events and mortality.

Cardiovascular safety assessment of pramlintide in type 2 diabetes: results from a pooled analysis of five clinical trials

BACKGROUND

This report evaluated the cardiovascular safety of the amylin analog pramlintide-an existing diabetes injectable treatment-by comparing relevant cardiovascular adverse events (AEs) reported in previous phase 3 and 4 clinical trials among patients receiving pramlintide and those receiving control treatments.

METHODS

Cardiovascular safety of pramlintide was assessed using accepted regulatory medical definitions of AEs reported in five randomized, controlled phase 3 and 4 trials of 16-52 weeks' duration in adults with type 2 diabetes. The original trials compared pramlintide (90-120 mcg twice daily or 30-150 mcg three times daily) with placebo (four studies) or a mealtime rapid-acting insulin analog (one study). Background therapies included insulin alone or in combination with oral glucose-lowering agents. AE data obtained from clinical study reports were combined into one database and analyzed for the intention-to-treat population of 2016 patients (pramlintide, n = 1434; pooled comparator, n = 582). The primary analysis compared reported major adverse cardiovascular events (MACE) between pramlintide and control.

RESULTS

The incidence of reported MACE was similar between pramlintide (4.7 %) and pooled comparators (4.5 %). Secondary analyses included MACE relative risk and hazard ratio point estimates, which ranged from 0.86 to 0.93 for pramlintide relative to comparator treatment; the upper limit of the two-sided 95 % confidence interval did not exceed the threshold of 1.8.

CONCLUSIONS

Both the point estimate of the reported MACE frequency and estimated risk ratios showed that mealtime pramlintide as an adjunct to insulin conferred no increased risk of cardiovascular AEs in patients with type 2 diabetes using insulin.

Association of silent hypoglycemia with cardiac events in non-diabetic subjects with acute myocardial infarction undergoing primary percutaneous coronary interventions

Background

Some studies have shown that hypoglycemic episodes in diabetic patients might be associated with increased cardiovascular events. It is not clear whether episodes of silent hypoglycemia had greater prognostic value on cardiac events compared with normoglycemia or hyperglycemia in non-diabetic patients, so the aim of this study was to investigate the association of silent hypoglycemia and cardiac events in non-diabetic patients with acute ST-segment elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (p-PCI).

Methods

We enrolled non-diabetic patients with STEMI who underwent p-PCI and whose clinical and laboratory data were collected. Interstitial glucose values were recorded using a continuous glucose monitoring system (CGMS), and Holter monitoring was recorded for 3 days in parallel. Cardiac ischemia and ventricular arrhythmia was evaluated.

Results

Based on the inclusion and exclusion criteria, we enrolled 164 STEMI patients undergoing p-PCI for final analysis. A total of 280 episodes of silent hypoglycemia (CGMS glucose <70 mg/dl) were recorded. Episodes of silent cardiac ischemia were recorded in 50 of 280 hypoglycemic episodes. The incidence of silent cardiac ischemia during hypoglycemia was significantly higher than the incidence during both hyperglycemia and normoglycemia(P < 0.01). Moreover, we found a significantly higher frequency of ventricular extrasystoles (VESs) or nonsustained ventricular tachycardias (NSVTs) in patients with silent hypoglycemia. The average number of events of silent cardiac ischemia was also significantly increased in the silent hypoglycemia group (0.91 ± 0.82 vs. 0.35 ± 0.54, P < 0.01) compared with either hyperglycemia or normoglycemia group.

Conclusions

Hypoglycemia was frequent and most of the time asymptomatic in non-diabetic patients with STEMI undergoing p-PCI. Silent hypoglycemia was associated with silent cardiac ischemia. STEMI patients with silent hypoglycemia had a significantly higher frequency of VESs or NSVTs.