Lipids in type 2 diabetes

Type 2 diabetes increases the risk of cardiovascular disease two- to fourfold compared to the risk in nondiabetic subjects. Although type 2 diabetes is associated with a clustering of risk factors, the cause for an excess risk of cardiovascular disease remains unknown. Lipid and lipoprotein abnormalities in type 2 diabetes include particularly elevated levels of total and very low-density lipoprotein triglycerides and reduced levels of high-density lipoprotein (HDL) cholesterol. Total and low-density lipoprotein (LDL) cholesterol levels are usually normal if glycemic control is adequate but LDL particles are small and dense. According to prospective population-based studies, total cholesterol is a similar risk factor for coronary heart disease (CHD) in patients with type 2 diabetes as it is in nondiabetic subjects. High total triglycerides and low HDL cholesterol may be even stronger risk factors for CHD in patients with type 2 diabetes than in nondiabetic subjects. Recent drug treatment trials have indicated that the lowering of total and LDL cholesterol by statins, and the lowering of total triglycerides and the raising of HDL cholesterol by fibrates, are at least as beneficial in diabetic patients as in nondiabetic subjects in the prevention of cardiovascular disease.     

2型糖尿病患者心率变异性分析

目的:分析2型糖尿病对心率变异性的影响。方法:对31例2型糖尿病患者和健康对照组进行24 h动态心电图监测,并测定心率变异性时域指标SDNN、SDNNIndex、SDANN、rMSSD、PNN50和频域指标TF、LF、HF、LF/HF和24h平均心率。结果:2型糖尿病患者心率变异性指标较对照组显著降低（P<0.05或P<0.01）。结论:2型糖尿病患者心率变异性减低,提示心脏自主神经功能受损。     

Devoting attention to glucose variability and hypoglycaemia in type 2 diabetes

In the Trial Comparing Cardiovascular Safety of Insulin Degludec vs Insulin Glargine in Patients with Type 2 Diabetes at High Risk of Cardiovascular Events (DEVOTE), insulin degludec was non-inferior to insulin glargine in terms of cardiovascular events and mortality. However, there were lower rates of severe hypoglycaemia with insulin degludec. DEVOTE investigators now extend these findings by presenting the results of two observational epidemiological analyses based on trial data. In the first of these analyses (DEVOTE 2), Zinman et al (Diabetologia DOI:  10.1007/s00125-017-4423-z) demonstrate that, compared with individuals with lower day-to-day fasting glycaemic variability, those with higher day-to-day fasting glycaemic variability had a similar risk of major adverse cardiovascular events (MACE) but a higher risk of severe hypoglycaemia and all-cause mortality. In the second analysis (DEVOTE 3), Pieber et al (Diabetologia DOI:  10.1007/s00125-017-4422-0) found that individuals who experienced severe hypoglycaemia had a similar risk of MACE compared with those who never experienced severe hypoglycaemia, but had a more than twofold higher risk of subsequent total mortality and cardiovascular disease (CVD) mortality. The strengths of these studies relate to the availability of high-quality prospective data on adjudicated severe hypoglycaemia, MACE and mortality events in a large number of high-risk insulin-treated individuals with type 2 diabetes. Limitations include the observational nature of the data and thus residual confounding remains possible. Furthermore, the short duration of the trial resulted in limited statistical power for some analyses. Therefore, whilst DEVOTE 2 and DEVOTE 3 raise awareness of the mortality risks associated with glucose variability and severe hypoglycaemia in high-risk, insulin-treated patients with type 2 diabetes, they cannot clarify causal relationships. Preventing severe hypoglycaemia in those with type 2 diabetes should already be a priority in clinical practice. However, findings from future clinical trials are needed to guide physicians on whether it is beneficial to target glucose variability, and risk for severe hypoglycaemia, to reduce the risks for CVD events and mortality in these individuals.     

高血压合并2型糖尿病患者心率变异性分析

目的：分析高血压合并2型糖尿病患者的心率变异性（heart rate variability,HRV）。方法收集本院收治的60例高血压合并2型糖尿病患者作为A组、60例高血压患者作为B组、60例正常体检者作为C 组。对3组研究对象均行24 h 动态心电图记录。比较各组的HRV指标。结果 A组患者的1 d内正常RR标准差（SDNN ）、5 min时段RR间期均值标准差（SDANN）、5 min 节段 RR 间期平均值标准差（SDNN index）,连续 RR 间期差值均方根（rMSSD）和相邻正常 RR 间期差值＞50 ms 百分比（pNN50）分别为（97．88±25．77）ms、（83．24±20．13）ms、（14．55±10．57）ms、（17．95±8．55）ms、（3．56±2．44）％,显著低于B组的（122．41±20．33）ms、（104．56±19．73）ms、（45．22±12．45）ms、（22．44±6．44）ms、（8．83±4．95）％和C组的（138．23±22．44）ms、（127．95±21．84）ms、（59．35±16．44）ms、（35．96±14．33）ms、（13．56±11．24）％。B组亦低于C 组,差异均有统计学意义（P＜0．05）。结论利用HRV 可在早期有效发现高血压合并2型糖尿病患者自主神经功能损伤程度,安全可靠,值得临床推广。     

2型糖尿病患者心率变异性与视网膜病变关系的研究

观察不并发和并发视网膜病变的2型糖尿病患者的心率变异性(HRV)，糖尿病并发视网膜病变者HRV显著降低，HRV变化与糖尿病视网膜病变相关。     

Hemorheology and heart rate variability in patients with diabetes mellitus type 2

Our study aimed to investigate the relationship between hemorheological parameters and heart rate variability (HRV) in patients with diabetes mellitus type 2. Hemorheological variables, including hematocrit (Ht), fibrinogen (Fib), whole blood (WBV) and plasma viscosity (PV) at shear rates of 0.0237 s(-1) to 128.5 s(-1) were examined in 20 patients with diabetes mellitus type 2 and in 10 control subjects. They all underwent non-invasive short-term monitoring of heart rate at rest and after passive head-up tilt. Measurement of the R-R intervals and calculation of the time domain parameters and the power spectral data were performed by our softwear, using fast Fourier transformation. Significant increase of Fib and WBV in the patients in comparison to controls was found within the range of shear rates 0.0237 s(-1) to 128.5 s(-1). In the diabetic patients parallel decrease of the total power (TP), the low frequency spectral power (LF) and of the mean RR and mild increase of the low frequency-high frequency ratio (LF/HF) at rest were established. This tendency was kept after the passive tilt. In patients with diabetes mellitus type 2 the increased blood viscosity was associated with reduced HRV.     

Heart rate variability and vibration perception threshold in type 2 diabetes mellitus

The aim of the study was to compare heart rate variability (HRV) and vibration perception threshold (VPT) of patients with type 2 diabetes mellitus (T2DM) with control. The study was conducted on 60 patients with T2DM and 30 controls. The short term HRV and VPT were assessed in the both groups. All the time domain measures, SDNN [26 (15.5–35) vs 36 (30–40.25) ms, P?=?0.002], RMSSD [25.9 (11.95–40.45) vs 36.65 (27.05–44.13) ms, P?=?0.002], and pNN50 [3.5 (0.23–21.83) vs 16.4 (4.45–27.63) %, P?=?0.002] were less in T2DM. Similarly, in frequency domain, low frequency (LF) power [81 (32–148.75) vs 126 (85.25–237.75) ms², P?=?0.007], high frequency (HF) power [81 (16.75–187.75) vs 182.5 (121.50–281.75) ms², P?=?0.001] and HF nu [54.5 (33.2–63.83) vs 59.7 (50–75.05), P?=?0.03] were significantly less in T2DM. Whereas, LF nu [45.25 (35.28–63.93) vs 44.65 (33.7–65.35)] and LF/HF ratio [0.78 (0.54–1.13) vs 0.7 (0.4–1)] were comparable between the groups. In Poincare plot, SD1 [18.5 (8.73–28.98) vs 26.2 (19.33–31.65) ms, P?=?0.003] and SD2 [37 (26.13–51.18) vs 48.6 (39.63–56.15) ms, P?=?0.016] as well as the ratio of SD1/SD2 [0.18 (0.14–0.21) vs 0.29 (0.25–0.33) P?=?0.001] were less in T2DM. However, VPT was comparable between the groups. The patients with T2DM had reduced parasympathetic activity whereas sympathetic activity and vibration (somatic) sensation were similar. It indicates that cardiac parasympathetic activity in T2DM is affected before sympathetic and somatic activity.     

Trajectories of fasting plasma glucose variability and mortality in type 2 diabetes

Aim

To investigate the effect of changes in fasting plasma glucose (FPG) variability, as assessed by 2-year trajectories of FPG variability, on mortality risk in patients with type 2 diabetes (T2D).

Sleep quality and heart rate variability in adolescents with type 1 or type 2 diabetes

IntroductionDecreased sleep quality and lower heart rate variability (HRV) have both independently been associated with diabetes and may contribute to risks for cardiovascular disease. Although poor sleep quality has been associated with lower HRV in adults with type 2 diabetes (T2D), studies of sleep quality in adolescents with (T2D) or studies examining the possible association of poor sleep quality with lower HRV in adolescents with T2D or T1D are not available.AimThus, we conducted a secondary analysis of data from an existing study to determine if there were associations between sleep quality and HRV in adolescents with T1D or T2D.MethodsAdolescents with T1D (n = 101) or T2D (n = 37) completed 24-h HRV Holter monitoring and analysis and a self-reported global measure of sleep quality. Results: Poor sleep quality was significantly associated with lower HRV, a known predictor for CV risk. Those with T2D had lower measures of HRV.ConclusionsThe evaluation of sleep quality and early signs of cardiovascular autonomic changes should be considered in routine assessments of adolescents with diabetes. Future research is warranted to examine more robust measures of sleep and HRV in adolescents with diabetes.     

Lipids and lipoprotein(a) concentrations in Pakistani patients with type 2 diabetes mellitus

AIM: The aim of the present study was to analyze serum lipoprotein(a) [Lp(a)] levels in Pakistani patients with type 2 diabetes mellitus (DM) and to find correlations between clinical characteristics and dyslipidaemias in these patients. METHODS: Fasting blood samples were analyzed for Lp(a), total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), glucose and glycosylated haemoglobin (HbA1c) in 68 Pakistani patients with type 2 DM and 40 non-diabetic healthy control subjects. RESULTS: Lp(a) levels were significantly raised in diabetics as compared to the control group. No correlation of Lp(a) was seen with age, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP) and fasting glucose. There was a positive correlation of BMI to SBP and DBP. There was a significant positive correlation between Lp(a) and total cholesterol and LDL-c. No correlation of Lp(a) was observed with HDL-c, triglycerides and glycosylated haemoglobin (HbA1c). CONCLUSION: The present study led us to conclude that serum Lp(a) levels are significantly raised in type 2 DM and have a positive correlation with serum total and LDL-c levels.     

Heart rate variability and diastolic dysfunction in patients with type 2 diabetes mellitus

Cardiovascular autonomic neuropathy is a common form of autonomic dysfunction in diabetes mellitus (DM) and associates abnormalities in heart rate control and in vascular dynamics. This study evaluates the impact of diabetes mellitus on left ventricular diastolic dysfunction (LVDD) and heart rate variability in a group of type 2 diabetes mellitus without signs of cardiovascular disease. The study group consisted of 58 patients, aged 61 ± 8 years, diagnosed with type 2 DM. The subjects were selected from a series of 104 consecutive diabetic patients. All the subjects were on oral therapy or on diet for DM, and ECG was normal for all the subjects. The control group consisted of 45 healthy subjects, matched for age and sex. Heart rate variability was measured using a 24-h ECG monitoring system, and standard 2D and Doppler echocardiography was performed in all the subjects. There are significant differences between groups regarding disease duration, longer in patients with impaired relaxation (11.22 ± 9.17 vs. 8.31 ± 8.95 years), and disease control, worse in impaired relaxation group. Heart rate in impaired relaxation group is significantly higher than in controls, and higher, but not significantly, when compared with normal group (91 ± 10, vs. 88 ± 11 and 71 ± 11, respectively). Cardiac autonomic neuropathy was associated with LVDD in patients with type 2 DM, but without clinically manifest heart disease. Twenty-four-hour ECG monitoring and echocardiography can detect diabetic cardiomyopathy in early stages and should be performed in all subjects.     

Lipids,lipoproteins and apolipoproteins in type 1 (insulin-dependent) and type 2 (non-insulin-dependent) diabetes mellitus

Summary Total plasma cholesterol, triglycerides, VLDL-C, VLDL-TG, HDL-C and the apoproteins A-I, A-II, B and D were measured in 111 male non-obese diabetic patients and in 90 male control subjects of similar age and body weight distribution. Forty-eight patients had Type 1 (insulin-dependent diabetes) and 63 had Type 2 (non-insulin-dependent diabetes); all were in stable metabolic control while following an appropriate diet and therapy with insulin or oral hypoglycemic agents. HDL-C, apoA-I, apoB and the apoA-I/apoA-II ratio were significantly increased in the Type 1 patients, whereas the VLDL-C/VLDL-TG and LDL-C/apoB ratios were decreased significantly. Type 2 diabetics showed low HDL-C and low apoA-I/apoA-II ratio, while the values of apoA-I, A-II, D and the VLDL-C/VLDL-TG ratio were significantly higher than in controls. Type 1 diabetics in ‘fair’ metabolic control presented higher values of TG, VLDL-C, VLDL-TG and apoB than patients in ‘good’ control: lower values of apoA-I and of the ratios apoA-I/apoA-II, apoA-I/apoB and LDL-C/apoB were recorded in the same subgroup. In Type 2 diabetics no significant differences were observed according to metabolic control, with the exception of a higher apo-D value in subjects in ‘fair’ control. The data obtained support the view that good metabolic control may be important for the prevention of a relevant derangement of lipoprotein components, particularly in Type 1 patients. Partially supported by grant No. 83.02521.56 fromConsiglio Nazionale delle Ricerche (CNR), Roma, Italy (Progetto Finalizzato di Medicina Preventiva e Riabilitativa).     

Assessment of the association between glycemic variability and diabetes-related complications in type 1 and type 2 diabetes

Chronic hyperglycemia is the main risk factor for the development of diabetes-related complications in both type 1 and type 2 diabetes, but it is thought that frequent or large glucose fluctuations may contribute independently to diabetes-related complications.     

高血压合并2型糖尿病患者的心率变异性分析

目的探讨心率变异性对早期发现高血压及高血压合并2型糖尿病心脏植物神经病变的意义。方法选择21例高血压病人、15例高血压合并2型糖尿病病人和20例健康人进行24h动态心电图记录，分析比较。结果高血压组、高血压合并2型糖尿病组的SDNN、SDANN、SDNNindex、rMMSD、PNN50较正常对照组均有明显变化（p〈0．05）；高血压合并2型糖尿病组较高血压组也有明显变化（p〈0．05）。结论心率变异性可以作为早期发现高血压或合并2型糖尿病患者心脏植物神经损害的一个有效的无创方法。     

Moderate intensity exercise improves heart rate variability in obese adults with type 2 diabetes

AimThe aim of this study was to determine the effect of moderate aerobic exercise on heart rate variability (HRV) in obese adults with type 2 diabetes.MethodsForty-one obese adults with type 2 diabetes participated in this study. Anthropometric and metabolic parameters were measured, and resting electrocardiogram (ECG) for the HRV analysis at spontaneous respiration was recorded for 5 min in supine position before and after six months of supervised aerobic training given thrice-a-week.ResultsThe mean age, body mass index (BMI), and duration of diabetes of the study population were 44.1 ± 4.5 years, 30.94 ± 1.36 kg/m2, and 16.3 ± 2.7 years, respectively. In time domain variables, standard deviation of all RR intervals (SDNN), the square root of the mean of the sum of the squares of differences between adjacent RR intervals (RMSSD) and percentage of consecutive RR intervals that differ by more than 50 ms (pNN50) were significantly increased after exercise. In frequency domain variables, high frequency (HF) (ms2) and HF (nu) were significantly increased while low frequency (LF) (ms2) and LF/HF ratio were significantly decreased after exercise. But LF (nu) was unaffected after exercise.ConclusionThis study suggests that thrice-a-week moderate intensity aerobic exercise for six months improves cardiac rhythm regulation as measured by HRV in obese adults with type 2 diabetes     

Effect of supervised integrated exercise on heart rate variability in type 2 diabetes mellitus

BACKGROUND: Heart rate variability (HRV) reflects autonomic nervous system modulation of cardiac activity. There is a relationship between degrees of physical activity, HRV changes and the risk of cardiovascular disease. AIM: To study the effect of a supervised integrated exercise programme on HRV in type 2 diabetes mellitus (DM). METHODS: The study group consisted of 48 patients (27 males, mean age 62+/-7 years) with type 2 diabetes, of whom 28 underwent a special exercise programme whereas the remaining 20 did not and served as the control group. The supervised integrated exercise programme was applied for a period of 9 months. Deep breathing time domain HRV (difference between the shortest and the longest R-R interval over one minute) was measured at baseline and after 3, 6 and 9 months. RESULTS: A significant improvement in the HRV values was observed with increasing duration of exercise (13.03+/-1.08 beats/min at baseline versus 16.5+/-1.11 beats/min at 9 months, p <0.001) whereas HRV decreased in the control group (14.85+/-1.15 beats/min at baseline vs. 14.30+/-1.75 at 9 months, p <0.05). Favourable changes in HRV in the exercise group were gender-dependent and were significant in males (12.4+/-1.76 beats/min at baseline vs. 16.18+/-1.91 at 9 months, p <0.001) whereas in females only a trend towards HRV improvement was observed. The HRV changes were also age-dependent and were more pronounced in younger patients than in the elderly. The metabolic parameters of diabetes control (blood glucose and glycosylated haemoglobin levels) significantly improved in the exercise group and significantly worsened in the control group. CONCLUSIONS: Regular supervised integrated exercise significantly improves HRV in patients with type 2 DM, which may favourably influence their long-term prognosis.     

Lixisenatide reduces glycaemic variability in insulin‐treated patients with type 2 diabetes

Chronic hyperglycaemia and glucose variability are associated with the development of chronic diabetes‐related complications. We conducted a pooled analysis of patient‐level data from three 24‐week, randomized, phase III clinical trials to evaluate the impact of lixisenatide (LIXI) on glycaemic variability (GV) vs placebo as add‐on to basal insulin. The main outcome GV measures were standard deviation (s.d.), mean amplitude of glycaemic excursions (MAGE), mean absolute glucose (MAG) level, area under the curve for fasting glucose (AUC‐F), and high (HBGI) and low blood glucose index (LBGI). The change in GV metrics over 24 weeks and relationships among baseline GV, patient characteristics and outcomes were assessed. Data were pooled from 1198 patients (665 LIXI, 533 placebo). Values for s.d., MAG level, MAGE, HBGI, and AUC‐F significantly decreased with LIXI vs placebo, while LBGI values were unchanged. Higher baseline GV measures correlated with older age, longer type 2 diabetes duration, lower body mass index, higher baseline glycated/haemogobin, greater reduction in postprandial glucose (PPG) level, and higher rates of symptomatic hypoglycaemia. These data show that LIXI added to basal insulin significantly reduced GV and PPG excursions vs placebo, without increasing the risk of hypoglycaemia (LBGI).     

Glycaemic variability and hypoglycaemia are associated with C-peptide levels in insulin-treated type 2 diabetes

AimThe aim of the study was to evaluate the association between C-peptide levels, glycaemic variability and hypoglycaemia in patients with insulin-treated type 2 diabetes (T2D).MethodsA total of 98 patients with T2D treated with basal-bolus insulin were enrolled in a cross-sectional study. Glycaemic variability and hypoglycaemia were assessed from continuous glucose monitoring (CGM) data recorded over 6 days: Glycemic variability was assessed by calculating the mean coefficient of variation (CV), while hypoglycemia was defined as sensor glucose levels ≤ 3.9 mmol/L or < 3.0 mmol/L. Fasting C-peptide and fasting glucose were measured on day 1.ResultsLow levels of fasting C-peptide correlated with higher CV (r = −0.53, P < 0.0001). In a multivariate regression model with HbA_1c, body mass index, diabetes duration and total daily insulin dose, only C-peptide was significantly associated with CV. Patients with ≥ 1 episode of hypoglycaemia had significantly lower median C-peptide levels than patients without hypoglycaemia (274 (136–620) pmol/L vs. 675 (445–1013) pmol/L, respectively; P = 0.0004). Also, 17 patients clinically diagnosed with T2D had detectable glutamic acid decarboxylase (GAD) antibodies (≥ 5 U/mL). These GAD-positive patients had significantly lower fasting C-peptide, higher CV and greater frequency of hypoglycaemia than GAD-negative patients.ConclusionIn patients with insulin-treated T2D, low levels of C-peptide are associated with greater glycaemic variability and higher risk of hypoglycaemia, suggesting that C-peptide levels should be taken into consideration when optimizing insulin treatment and assessing hypoglycaemia risk.