The effect of improved post-prandial blood glucose control on post-prandial metabolism and markers of vascular risk in people with Type 2 diabetes

Glucose variability: a new risk factor for cardiovascular disease

AIMS AND DATA SYNTHESIS

Glucose variability (GV) is increasingly considered an additional index of glycemic control. Growing evidence indicates that GV is associated with diabetic vascular complications, thus being a relevant point to address in diabetes management. GV can be measured using various parameters, but to date, a gold standard has not been identified. This underscores the need for further studies in this field also to identify the optimal treatment.

CONCLUSIONS

We reviewed the definition of GV, the pathogenetic mechanisms of atherosclerosis, and its relationship with diabetic complications.

Pharmacokinetic and pharmacodynamic bioequivalence of biosimilar MYL-1601D with US and European insulin aspart in healthy volunteers: A randomized, double-blind, crossover, euglycaemic glucose clamp study

AIM

To evaluate the pharmacokinetic (PK) and pharmacodynamic (PD) bioequivalence (BE) of MYL-1601D biosimilar with originator, NovoLog (Ref-InsAsp-US), and NovoRapid (Ref-InsAsp-EU).

MATERIALS AND METHODS

This was a double-blind, randomized, crossover study that enrolled 71 healthy subjects to receive a single subcutaneous dose (0.2 U/kg) of each formulation under automated euglycaemic clamp conditions (ClampArt, level 81 mg/dL, duration 12 hours postdose). Primary PK endpoints were area under the plasma insulin aspart concentration-time curve from 0 to 12 hours (AUC0-12h ) and maximum plasma insulin aspart concentration (Cmax ). Primary PD endpoints were area under the glucose infusion rate (GIR) time curve from 0 to 12 hours (AUCGIR0-12h ) and maximum GIR (GIRmax ). Insulin aspart in plasma was quantified using immunoaffinity purification followed by ultraperformance liquid chromatography and tandem mass spectrometric detection. The pairwise comparisons of geometric least square mean (LS-mean) ratio for a 90% confidence interval (CI) of primary PK, and 90% CIs (MYL-1601D vs. Ref-InsAsp-US) and 95% CIs (MYL-1601D vs. Ref-InsAsp-EU) of primary PD variables, were to be within 80% to 125% to show BE.

RESULTS

MYL-1601D showed PK BE to both Ref-InsAsp-US (AUC0-12h geometric LS-mean ratio 102.17, 90% CI [100.26; 104.11]; Cmax 106.13 [100.71; 111.85]) and Ref-InsAsp-EU (AUC0-12h 101.84 [100.04; 103.67]; Cmax 105.74 [101.09; 110.60]). Likewise, MYL-1601D showed PD BE to Ref-InsAsp-US (AUCGIR_0-last 99.93; 90% CI [95.74; 104.30]; GIR_max 100.12 [94.46; 106.12]) and Ref-InsAsp-EU (AUCGIR_0-last 96.42; 95% CI [91.17; 101.98]; GIR_max 95.10 [89.37; 101.19]). All three insulin aspart products were well tolerated.

CONCLUSION

MYL-1601D showed BE to Ref-InsAsp-US and Ref-InsAsp-EU with a comparable safety profile.

Alleviating effects of lupeol on postprandial hyperglycemia in diabetic mice

This study aimed to investigate the inhibition activities of lupeol on carbohydrate digesting enzymes and its ability to improve postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. α-Glucosidase and α-amylase inhibitory assays were executed using a chromogenic method. The effect of lupeol on hyperglycemia after a meal was measured by postprandial blood glucose in STZ-induced diabetic and normal mice. The mice were treated orally with soluble starch (2 g/kg BW) alone (control) or with lupeol (10 mg/kg BW) or acarbose (10 mg/kg BW) dissolved in water. Blood samples were taken from tail veins at 0, 30, 60, and 120 min and blood glucose was measured by a glucometer. Lupeol showed noticeable inhibitory activities on α-glucosidase and α-amylase. The half-maximal inhibitory concentrations (IC₅₀) of lupeol on α-glucosidase and α-amylase were 46.23 ± 9.03 and 84.13 ± 6.82 μM, respectively, which were more significantly effective than those of acarbose, which is a positive control. Increase in postprandial blood glucose level was more significantly lowered in the lupeol-administered group than in the control group of both STZ-induced diabetic and normal mice. In addition, the area under the curve was significantly declined with lupeol administration in the STZ-induced diabetic mice. These findings suggest that lupeol can help lower the postprandial hyperglycemia by inhibiting carbohydrate-digesting enzymes.

Insulin Aspart in the Management of Diabetes Mellitus: 15 Years of Clinical Experience

Limiting excessive postprandial glucose excursions is an important component of good overall glycemic control in diabetes mellitus. Pharmacokinetic studies have shown that insulin aspart, which is structurally identical to regular human insulin except for the replacement of a single proline amino acid with an aspartic acid residue, has a more physiologic time-action profile (i.e., reaches a higher peak and reaches that peak sooner) than regular human insulin. As expected with this improved pharmacokinetic profile, insulin aspart demonstrates a greater glucose-lowering effect compared with regular human insulin. Numerous randomized controlled trials and a meta-analysis have also demonstrated improved postprandial control with insulin aspart compared with regular human insulin in patients with type 1 or type 2 diabetes, as well as efficacy and safety in children, pregnant patients, hospitalized patients, and patients using continuous subcutaneous insulin infusion. Studies have demonstrated that step-wise addition of insulin aspart is a viable intensification option for patients with type 2 diabetes failing on basal insulin. Insulin aspart has shown a good safety profile, with no evidence of increased receptor binding, mitogenicity, stimulation of anti-insulin antibodies, or hypoglycemia compared with regular human insulin. In one meta-analysis, there was evidence of a lower rate of nocturnal hypoglycemia compared with regular human insulin and, in a trial that specifically included patients with a history of recurrent hypoglycemia, a significantly lower rate of severe hypoglycemic episodes. The next generation of insulin aspart (faster-acting insulin aspart) is being developed with a view to further improving on these pharmacokinetic/pharmacodynamic properties.

1,5-anhydroglucitol as a useful marker for assessing short-term glycemic excursions in type 1 diabetes

BACKGROUND

Type 1 diabetes is associated with more severe glycemic variability and more frequent hypoglycemia than type 2 diabetes. Glycemic variability is associated with poor glycemic control and diabetic complications. In this study, we demonstrate the clinical usefulness of serum 1,5-anhydroglucitol (1,5-AG) for assessing changes in glycemic excursion in type 1 diabetes.

METHODS

Seventeen patients with type 1 diabetes were enrolled in this study. A continuous glucose monitoring system (CGMS) was applied twice at a 2-week interval to evaluate changes in glycemic variability. The changes in serum glycemic assays, including 1,5-AG, glycated albumin and hemoglobin A1c (HbA1c), were also evaluated.

RESULTS

Most subjects showed severe glycemic excursions, including hypoglycemia and hyperglycemia. The change in 1,5-AG level was significantly correlated with changes in the glycemic excursion indices of the standard deviation (SD), mean amplitude of glucose excursion (MAGE), lability index, mean postmeal maximum glucose, and area under the curve for glucose above 180 mg/dL (r=-0.576, -0.613, -0.600, -0.630, and -0.500, respectively; all P<0.05). Changes in glycated albumin were correlated with changes in SD and MAGE (r=0.495 and 0.517, respectively; all P<0.05). However, changes in HbA1c were not correlated with any changes in the CGMS variables.

CONCLUSION

1,5-AG may be a useful marker for the assessment of short-term changes in glycemic variability. Furthermore, 1,5-AG may have clinical implications for the evaluation and treatment of glycemic excursions in type 1 diabetes.

The effectiveness and safety of beginning insulin aspart together with basal insulin in people with type 2 diabetes in non-Western nations: results from the A₁chieve observational study

AIMS

The aim of this A₁chieve sub-group analysis was to examine populations beginning insulin aspart together with any basal insulin, all ± oral glucose lowering drugs: insulin aspart added to existing basal insulin (n=519); switched from biphasic insulin (n=947); switched from NPH plus human meal-time insulins (n=586); and insulin-naïve begun with basal plus insulin aspart (n=1594).

METHODS

A₁chieve was a 24-week non-interventional study evaluating insulin analogues in 66,726 people with type 2 diabetes in routine clinical care in 28 non-Western countries. Major endpoints were analysed as change from baseline using Student's paired t-test.

RESULTS

Baseline glycaemic control was poor (mean HbA1c: 9.4-10.1% [79-87 mmol/mol]). HbA₁c, FPG and PPPG improved significantly from baseline in all groups (mean change from baseline in HbA1c: -2.8 to -1.8% [-31 to -20 mmol/mol]; FPG: -4.9 to -2.9 mmol/L; PPPG: -6.7 to -3.9 mmol/L; p<0.001 for all), resulting in a similar level of blood glucose control for all groups at study end. Unsurprisingly, hypoglycaemia rates increased in those starting insulin, but decreased in the other groups. Clinically significant improvements in serum lipids and quality of life occurred across all groups.

CONCLUSIONS

These data support the use of basal plus prandial insulin regimens in routine clinical practice in people with type 2 diabetes with inadequate glycaemic control.

Lower incidence of recorded cardiovascular outcomes in patients with type 2 diabetes using insulin aspart vs. those on human regular insulin: observational evidence from general practices

AIMS

Insulin aspart has a higher ability to treat postprandial glucose than regular human insulin, which may have favourable cardiovascular effects. The aim was to collect and compare the incidence of recorded macro- and microvascular events in patients with type 2 diabetes with insulin aspart or regular human insulin in general practices.

METHODS

Computerized data from 3154 aspart and 3154 regular insulin users throughout Germany (Disease Analyzer, January 2000 to July 2011) were analysed after matching for age (60 ± 10 years), sex (men: 57%), health insurance (private: 5.8%) and diabetes treatment period in practice (2.2 ± 2.5 years). Hazard ratios (HR; Cox regression) for macro- or microvascular outcomes (follow-up: 3.5 years) were further adjusted for diabetologist care, practice region, hypertension, hyperlipidaemia, co-medication (basal insulin, oral antidiabetics, antihypertensives, lipid-lowering agents and antithrombotic drugs), previous treatment with rapid-acting insulins, hypoglycaemia and the Charlson co-morbidity score. Furthermore, adjustment was carried out for baseline microvascular complications when analysing macrovascular outcomes and vice versa.

RESULTS

Overall, the risk of combined macrovascular outcomes was 15% lower for insulin aspart users (p = 0.01). For insulin aspart there was also a decreased risk incident stroke [HR: 0.58; 95% confidence interval (CI): 0.45-0.74], myocardial infarction (HR: 0.69; 95% CI: 0.54-0.88) and peripheral vascular disease (HR: 0.80; 95% CI: 0.69-0.93). For microvascular complications (retinopathy, neuropathy and nephropathy), no significant differences were observed (HR: 0.96; 95% CI: 0.87-1.06).

CONCLUSION

Use of the rapid-acting insulin analogue aspart was associated with a reduced incidence of macrovascular outcomes in type 2 diabetes in general practices. It is important to confirm this finding in a randomized controlled trial.

Efficacy and safety comparison of rapid-acting insulin aspart and regular human insulin in the treatment of type 1 and type 2 diabetes mellitus: a systematic review

BACKGROUND

Insulin aspart (IAsp) is one of the three rapid-acting insulin analogues (RAAs) registered for the treatment of diabetes. However, there is an ongoing debate concerning the efficacy and safety of RAAs. For this reason, a systematic review-based study was performed to compare clinical outcomes of treatment with IAsp and regular human insulin (RHI) as well as biphasic insulin aspart and premixed human insulin in type 1 and type 2 diabetes (T1DM, T2DM) patients.

METHODS

Relevant articles were identified by a systematic search through the electronic medical databases (MEDLINE, EMBASE, CENTRAL) up to July 2009.

RESULTS

A total of 28 trials fulfilled the inclusion criteria, including 17 studies of T1DM, 10 of T2DM and one study of both. For T1DM, pooled data for HbA(1c) (13 studies) demonstrated lower levels with IAsp than with RHI (WMD=-0.11%; 95% CI: -0.16 to -0.06). In addition, meta-analysis revealed statistically significant differences in favour of IAsp for postprandial glucose (PPG) after breakfast, lunch and dinner, but not for fasting glucose (FG). The Diabetes Treatment Satisfaction Questionnaire evaluating treatment flexibility showed IAsp benefits compared with RHI (WMD=0.31; 95% CI: 0.15 to 0.47). Safety analyses (three studies) showed a significant reduction in nocturnal hypoglycaemia risk with IAsp (RR=0.67; 95% CI: 0.54 to 0.83), and no difference in severe hypoglycaemias and a slight increase in any hypoglycaemic episodes with RAAs (RR=1.06; 95% CI: 1.01 to 1.10). For T2DM, a meta-analysis of nine studies revealed no significant differences between IAsp and RHI in HbA(1c) (WMD=-0.04%; 95% CI: -0.10 to 0.03), whereas PPG was significantly lower in the IAsp group (WMD=-1.18 mmol/L; 95% CI: -1.88 to -0.47). No studies of treatment satisfaction or quality of life were identified.

CONCLUSION

Analyses based on a systematic review showed that treatment with IAsp in T1DM patients resulted in moderately better metabolic control and treatment satisfaction than RHI. In T2DM patients, meta-analysis showed improvement in PPG, but not in any other outcomes.

The cost effectiveness of rapid-acting insulin aspart compared with human insulin in type 2 diabetes patients: an analysis from the Japanese third-party payer perspective

OBJECTIVES

The Nippon Ultra-Rapid Insulin and Diabetic Complication Evaluation Study (NICE Study) (NCT00575172) was a 5-year, open-label, randomised controlled trial which compared cardiovascular outcomes in Japanese type 2 diabetes patients intensively treated with regular human insulin or insulin aspart (NovoRapid; Novo Nordisk A/S, Bagsvaerd, Denmark), a rapid-acting insulin analogue. The aim of the present analysis was to evaluate the cost effectiveness of insulin aspart versus regular human insulin from the perspective of a Japanese third-party healthcare payer.

RESEARCH DESIGN AND METHODS

A discrete event-simulation model was developed in Microsoft Excel to assess the within-trial cost effectiveness and make longer-term clinical projections in patients treated with regular human insulin or insulin aspart. In addition to severe hypoglycaemia, the model captured myocardial and cerebral infarction events and percutaneous coronary intervention and coronary artery bypass graft procedures. Within-trial mortality, incidence of severe hypoglycaemia and cardiovascular event probabilities were derived from the annual rates observed during the trial period, while post-trial outcomes were calculated using the event rates from the trial, adjusted for increasing patient age. Event costs were accounted from the healthcare payer perspective and expressed in 2008 Japanese yen (JPY), while health-related quality of life (HRQoL) was captured using event and state utilities. Future costs and clinical benefits were discounted at 3% annually. Life expectancy, quality-adjusted life expectancy, cardiovascular event rates and costs were evaluated over 5- and 10-year time horizons and sensitivity analyses were performed to assess variability in model outcomes.

RESULTS

Over 5 years of treatment, insulin aspart dominated human insulin both in incremental life expectancy and in incremental quality-adjusted life-years (QALYS). Insulin aspart was associated with a small improvement in discounted life expectancy of 0.005 years (4.688 vs. 4.684 years) and an increase of 0.023 quality-adjusted life-years (QALYs) (3.800 vs. 3.776 QALYs) when compared with regular human insulin. Insulin aspart also incurred lower costs (JPY 481,586 vs. 594,717, difference -113,131) which resulted from the decreased incidence of cardiovascular events with insulin aspart (0.013 events per patient year vs. 0.030 on regular human insulin). Breakdown of costs indicated that pharmacy costs were higher with insulin aspart (JPY 346,608 vs. 278,468), but these costs were more than offset by the reduced costs associated with cardiovascular complications and hypoglycaemia over 5 years of treatment (JPY 134,978 vs. 316,249). Sensitivity analysis showed that insulin aspart was still cost-effective in the case where only 18% of the within-trial cardiovascular and mortality benefit over regular human insulin was captured in the model (assuming a willingness-to-pay threshold of JPY 5,000,000).

LIMITATIONS

The NICE study cohort was relatively small (n = 325), meaning that caution should be exercised when calculating and interpreting the incremental cost-effectiveness ratio. Also, despite the differences in cardiovascular risk profile between the Japanese and UK populations, UKPDS-derived risk equations were used to project MI outcomes and PCI and CABG procedures and UKPDS HRQoL scores were applied to all health states. While these risk formulas and HRQoL utilities may not be directly applicable to the Japanese population, no equivalent Japanese-specific data are currently available.

CONCLUSIONS

In a Japanese type 2 diabetes population, prescribing rapid-acting insulin aspart significantly reduced cardiovascular complications over 5- and 10-year time horizons, resulting in increased quality of life and decreased costs when compared with human insulin.

Inter-day glycemic variability assessed by continuous glucose monitoring in insulin-treated type 2 diabetes patients on hemodialysis

BACKGROUND

Type 2 diabetes patients on chronic hemodialysis have a high prevalence of cardiovascular complications and often show a poor glycemic control. Single-spot glycemic measurements are not always meaningful, and the hemoglobin A1c (HbA1c) value does not reflect short-term variations in glucose metabolism in this patient category. Therefore, to better understand their metabolic balance, we studied a group of diabetes patients on hemodialysis by a continuous glucose monitoring (CGM) system.

METHODS

Twelve insulin-treated type 2 diabetes patients on hemodialysis were studied by a microdialysis-based subcutaneous glucose sensor over a period of 2 days, including the dialysis day (HD) and the following inter-dialytic period ("free" day [FD]).

RESULTS

The mean 24-h glycemic value, the mean amplitude of glucose excursions, and the SD of mean glucose were significantly higher in the HD than the FD (186 ± 50 vs. 154 ± 25 mg/dL, P<0.05; 75 ± 22 vs. 56 ± 15 mg/dL, P<0.05; and 57 ± 6 vs. 35 ± 11 mg/dL, P<0.05, respectively). Considering the 48-h recording, there was a direct correlation between the mean glucose concentration and the HbA1c (r=0.47, P<0.05), whereas no association was observed between the measures of glucose variability and HbA1c.

CONCLUSIONS

Insulin-treated diabetes patients on hemodialysis showed different glucose profiles between the HD and the FD. In particular, in the HD they have had an increased glycemic variability, which may represent an adjunctive risk factor for cardiovascular complications. Therefore the use of a CGM system, as a means of assessing the measures of glycemic variability, could improve the management of insulin therapy in these patients.

Multifocal ERG defects associated with insufficient long-term glycemic control in adolescents with type 1 diabetes

PURPOSE

To investigate the relationship between long-term glycemic control and localized neuroretinal function in adolescents with type 1 diabetes (T1D) without diabetic retinopathy (DR).

METHODS

Standard (103 hexagons) and slow-flash (61 hexagons) multifocal ERGs (standard mfERG and sf mfERG) were recorded in 48 patients and 45 control subjects. Hexagons with delayed responses were identified as abnormal. Negative binomial regression analysis was conducted with the number of abnormal hexagons as the outcome variable. Glycated hemoglobin (HbA(1c)) levels, time since diagnosis of T1D, age at diagnosis of T1D, age at testing, and sex were the covariates. Another model replacing HbA(1c) closest to the date of testing with a 1-year average was also generated.

RESULTS

There were more abnormal hexagons for mfOPs in patients than in control subjects (P = 0.005). There was no significant difference in the mean number of abnormal hexagons for standard mfERG responses between patients and control subjects (P = 0.11). Negative binomial regression analysis for the standard mfERG data demonstrated that a 1-unit increase in HbA(1c) was associated with an 80% increase in the number of abnormal hexagons (P = 0.002), when controlling for age at testing. Analysis using the 1-year HbA(1c) averages did not result in significant findings.

CONCLUSIONS

Poor long-term glycemic control is associated with an increase in areas of localized neuroretinal dysfunction in adolescents with T1D and no clinically visible DR. Stricter glucose control during the early stages of the disease may prevent neuroretinal dysfunction in this cohort.

Glucose information for tight glycemic control: different methods with different challenges

Rigorous glucose control is essential for prevention of diabetes-related complications in diabetes patients. Even without diabetes, tight glucose control is beneficial in hospitalized, critically ill patients. Actually, three different glucose measurement methods are used: (1) hand held devices, (2) blood-gas analyzers, and (3) laboratory analyzers in core laboratories. Each method is subject to specific challenges and limitations that can affect the overall system performance. In this article, we aim to demonstrate that even glucose measurement results from core laboratories (professional laboratory systems) do not necessarily reflect the absolute "true" glucose level of a patient.

The assessment of glycemic variability and its impact on diabetes-related complications: an overview

There is a growing body of evidence that the sole use of hemoglobin A1c is insufficient to adequately reflect the metabolic situation of patients with diabetes mellitus. The risk of developing diabetes-related complications apparently not only depends on the long-term stability of glucose values, but also on the presence or occurrence of short-term glycemic peaks and nadirs lasting for minutes or hours during a day. This leads to the phenomenon of glycemic variability. This article reviews the existing evidence for the clinical relevance of short-term glucose variations and the currently available different means of measuring glycemic variability.

Efficacy and safety of insulin analogues for the management of diabetes mellitus: a meta-analysis

BACKGROUND

Although insulin analogues are commonly prescribed for the management of diabetes mellitus, there is uncertainty regarding their optimal use. We conducted meta-analyses to compare the outcomes of insulin analogues with conventional insulins in the treatment of type 1, type 2 and gestational diabetes.

METHODS

We updated 2 earlier systematic reviews of the efficacy and safety of rapid-and long-acting insulin analogues. We searched electronic databases, conference proceedings and "grey literature" up to April 2007 to identify randomized controlled trials that compared insulin analogues with conventional insulins. Study populations of interest were people with type 1 and type 2 diabetes (adult and pediatric) and women with gestational diabetes.

RESULTS

We included 68 randomized controlled trials in the analysis of rapid-acting insulin analogues and 49 in the analysis of long-acting insulin analogues. Most of the studies were of short to medium duration and of low quality. In terms of hemoglobin A1c, we found minimal differences between rapid-acting insulin analogues and regular human insulin in adults with type 1 diabetes (weighted mean difference for insulin lispro: -0.09%, 95% confidence interval [CI] -0.16% to -0.02%; for insulin aspart: -0.13%, 95% CI -0.20% to -0.07%). We observed similar outcomes among patients with type 2 diabetes (weighted mean difference for insulin lispro: -0.03%, 95% CI -0.12% to -0.06%; for insulin aspart: -0.09%, 95% CI -0.21% to 0.04%). Differences between long-acting insulin analogues and neutral protamine Hagedorn insulin in terms of hemoglobin A1c were marginal among adults with type 1 diabetes (weighted mean difference for insulin glargine: -0.11%, 95% CI -0.21% to -0.02%; for insulin detemir: -0.06%, 95% CI -0.13% to 0.02%) and among adults with type 2 diabetes (weighted mean difference for insulin glargine: -0.05%, 95% CI -0.13% to 0.04%; for insulin detemir: 0.13%, 95% CI 0.03% to 0.22%). Benefits in terms of reduced hypoglycemia were inconsistent. There were insufficient data to determine whether insulin analogues are better than conventional insulins in reducing long-term diabetes-related complications or death.

INTERPRETATION

Rapid-and long-acting insulin analogues offer little benefit relative to conventional insulins in terms of glycemic control or reduced hypoglycemia. Long-term, high-quality studies are needed to determine whether insulin analogues reduce the risk of long-term complications of diabetes.

The effect of the optimal use of rapid-acting insulin analogues on insulin secretion in Type 2 diabetes

The abnormal glucose tolerance of Type 2 diabetes is characterized by post-prandial hyperglycaemia. We aimed to examine whether the restoration of a more physiological insulin profile using rapid-acting insulin analogues might, through effects on glucose toxicity, improve endogenous insulin secretion rate (ISR) and secondly improve markers of vascular risk. Eighteen people with insulin-treated Type 2 diabetes were recruited into a single centre, cross-over, open-labeled study. The order of pre-meal unmodified human insulin or insulin aspart was randomized: treatment periods lasted at least 8-12 weeks after which ISR was assessed by stepped low-dose glucose infusion and fasting markers of vascular risk measured. Glucose control was good (HbA(1c) 6.94+/-0.12 (+/-S.E.)% versus 7.07+/-0.13%, NS) with insulin aspart and human insulin. Mean post-prandial self-monitored blood glucose concentration was also good particularly with insulin aspart (7.5+/-0.41 mmol/l versus 8.19+/-0.34 mmol/l) but the difference did not reach statistical significance. Over 160 min ISR did not differ between insulin aspart and human insulin and there was also no change in various markers of vascular risk. In conclusion a meal-time+basal insulin regimen gave close to normal post-prandial blood glucose control with both the insulin aspart and human insulin regimens, such that no difference in ISR or markers of vascular risk could be demonstrated.

Premeal insulin lispro plus bedtime NPH or twice-daily NPH in patients with type 2 diabetes: acute postprandial and chronic effects on glycemic control and cardiovascular risk factors

OBJECTIVE

Two insulin regimens were used to explore acute and chronic postprandial changes in glycemia, lipemia, and metabolic markers associated with increased risk of cardiovascular disease.

METHODS

An open-label, randomized, two-period crossover study (12 weeks/period) compared a prandial regimen [premeal insulin lispro+bedtime neutral protamine Hagedorn (NPH)] with a basal regimen (twice-daily NPH). There were 30 patients (12 women and 18 men; mean age=61 years) with type 2 diabetes mellitus (mean duration=16 years) who were randomized after a 2-month lead-in with twice-daily NPH treatment. A standard lunch test meal developed according to each patient's caloric needs was administered at the end of each treatment period.

RESULTS

Insulin lispro was associated with significantly lower postprandial glucose (area under the curve0-5 h=43.54 vs. 57.65 mM/h; P<.001), elevated insulin concentrations, and acutely altered lipid fractions that included an early decrease followed by an increase in free fatty acids, lower triglycerides, elevated total cholesterol, elevated low-density lipoprotein cholesterol (LDL), and elevated high-density lipoprotein cholesterol. After 12 weeks of treatment, insulin lispro+bedtime NPH reduced hemoglobin A1c (HbA1c; mean+/-SE=7.6+/-0.2 vs. 8.2+/-0.2%; P<.001) without increasing hypoglycemia or insulin dose as compared with twice-daily NPH. Furthermore, treatment with the prandial insulin regimen resulted in lower total cholesterol, lower LDL cholesterol, and lower oxidized LDL.

CONCLUSION

Improved postprandial glycemic control, as observed in a regimen containing both prandial insulin lispro and NPH as the basal insulin, is associated with significantly lower HbA1c and acute modulation of lipid fractions after a test meal. These biochemical modifications may potentially have a favorable impact on cardiovascular risk in patients with type 2 diabetes mellitus.

Effects of nateglinide and glibenclamide on prothrombotic factors in naïve type 2 diabetic patients treated with metformin: a 1-year, double-blind, randomized clinical trial

OBJECTIVE

To evaluate the effect on coagulation and fibrinolysis parameters and on non-conventional cardiovascular risk factors of metformin plus nateglinide or glibenclamide in naïve type 2 diabetes patients.

PATIENTS AND METHODS

A total of 248 type 2 diabetic patients were enrolled and randomly assigned to receive nateglinide or glibenclamide, and metformin for 12 months. We assessed body mass index (BMI), glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), postprandial plasma glucose (PPG), fasting plasma insulin (FPI), postprandial plasma insulin (PPI), homeostasis model assessment index (HOMA index), lipid profile with lipoprotein (a) [Lp(a)], fibrinogen (Fg), plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (t-PA), homocysteine (Hcy), systolic blood pressure (SBP), diastolic blood pressure (DBP).

RESULTS

After 9 months of treatment, both tested drug combinations were similarly associated with a significant reduction in FPG (nateglinide, -17.2%; glibenclamide, -16.9%, both p<0.05) compared to the baseline, while HbA1c (-17.3%, p<0.05) and PPG (-15.2%, p<0.05) significantly decreased only in the nateglinide group. After one year of treatment, compared to the baseline the nateglinide group showed a significant reduction in HbA1c (-21%, p<0.01), FPG (-20.7%), p<0.01, PPG (-21.5%, p<0.05), HOMA index (-25.4%, p<0.05); the glibenclamide group, showed a significant reduction in HbA1c (-11%, p<0.05), FPG (-23.2%, p<0.05), PPG (-11.2%, p<0.05), and HOMA index (-23.9%, p<0.05) but to a minor extent. Moreover, the HbA1c difference value from baseline observed in the nateglinide-treated group was significantly higher than that observed in the glibenclamide group. Therefore the nateglinide-treated patients showed a significant reduction in some prothrombotic parameters (PAI-1=-19%, Lp(a)=-31%, and Hcy=-32.3%, all p<0.05), whereas the glibenclamide-treated patients did not.

CONCLUSION

Nateglinide appears to improve glycemic control as well as the levels of some prothrombotic parameters compared to glibenclamide when administered in combination with metformin.

Insulin aspart: a review

Insulin aspart, an analogue of human insulin, which is approved for use in people with diabetes, is more rapidly absorbed and achieves higher plasma concentrations than human soluble insulin following subcutaneous injection. Hence, it has a faster and more effective glucose-lowering action, with superior control of postprandial hyperglycaemia compared with human soluble insulin. Its shorter duration of action makes interprandial and nocturnal hypoglycaemia less of a problem than with human soluble insulin. Insulin aspart is approved for use in continuous subcutaneous infusion and offers a valuable treatment option during pregnancy.

Glycemic control with regular versus lispro insulin sliding scales in hospitalized Type 2 diabetics

PURPOSE

The aim of this study was to compare glycemic control with either regular or lispro insulin sliding scales in hospitalized Type 2 diabetics who were not using insulin as outpatients.

METHODS

Forty-three patients with Type 2 diabetes, who were taking oral agents only, were admitted to a medical inpatient service and randomized to receive either regular or lispro insulin sliding scale. Oral agents for diabetes were held upon admission and patients were followed throughout their hospital stay.

RESULTS

There was no significant difference (P>.05) between the average finger-stick blood glucose (FSBG) in the regular insulin group (157.78+/-40.16 mg/dl) and the lispro insulin group (152.04+/-27.71 mg/dl). No significant difference was found between the daily dose of insulin (regular, 5.83+/-5.01 units; lispro, 4.27+/-3.40 units), total amount of insulin used during hospitalization (regular, 11.87+/-10.78 units; lispro, 12.77+/-14.39 units), glucose excursion (regular, 110.13+/-25.86 mg/dl; lispro, 106.77+/-52.65 mg/dl), or length of hospital stay (regular, 2.33+/-1.23 days; lispro, 2.69+/-1.59 days).

CONCLUSION

No significant difference in glycemic control was found in hospitalized Type 2 diabetic patients who received either regular or lispro insulin sliding scales. Both insulin sliding scales used in this study are inadequate to achieve current recommended glycemic targets in this patient population, when used as the only inpatient treatment for diabetes.

Short acting insulin analogues versus regular human insulin in patients with diabetes mellitus

BACKGROUND

Short acting insulin analogue use for diabetic patients is still controversial, as reflected in many scientific debates.

OBJECTIVES

To assess the effects of short acting insulin analogues versus regular human insulin.

SEARCH STRATEGY

The Cochrane Library (Issue 3, 2005), MEDLINE, EMBASE until September 2005.

SELECTION CRITERIA

Randomised controlled trials with an intervention duration of at least 4 weeks.

DATA COLLECTION AND ANALYSIS

Trial selection and evaluation of study quality was done independently by two reviewers.

MAIN RESULTS

Altogether 8274 participants took part in 49 randomised controlled studies. Most studies were of poor methodological quality. In patients with type 1 diabetes, the weighted mean difference (WMD) of HbA1c was -0.1% (95% CI: -0.2 to -0.1) in favour of insulin analogue, whereas in patients with type 2 diabetes the WMD was 0.0% (95% CI: -0.1 to 0.0). In subgroup analyses of different types of interventions in type 1 diabetic patients, the WMD in HbA1c was -0.2% (95% CI: -0.3 to -0.1) in favour of insulin analogue in studies using continuous subcutaneous insulin injections (CSII), whereas for conventional intensified insulin therapy (IIT) studies the WMD in HbA1c was -0.1% (95% CI: -0.1 to 0.0). The WMD of the overall mean hypoglycaemic episodes per patient per month was -0.2 (95% CI: -1.1 to 0.7) and -0.2 (95% CI: -0.5 to 0.1) for analogues in comparison to regular insulin in patients with type 1 diabetes and type 2 diabetes, respectively. For studies in type 1 diabetes patients the incidence of severe hypoglycaemia ranged from 0 to 247.3 (median 21.8) episodes per 100 person-years for insulin analogues and from 0 to 544 (median 46.1) for regular insulin, in type 2 the incidence ranged from 0 to 30.3 (median 0.3) episodes per 100 person-years for insulin analogues and from 0 to 50.4 (median 1.4) for regular insulin. No study was designed to investigate possible long term effects (e.g. mortality, diabetic complications), in particular in patients with diabetes related complications.

AUTHORS' CONCLUSIONS

Our analysis suggests only a minor benefit of short acting insulin analogues in the majority of diabetic patients treated with insulin. Until long term efficacy and safety data are available we suggest a cautious response to the vigorous promotion of insulin analogues. For safety purposes, we need a long-term follow-up of large numbers of patients and well designed studies in pregnant women to determine the safety profile for both the mother and the unborn child.