Glycemic exposure is affected favorably by inhaled human insulin (Exubera) as compared with subcutaneous insulin glargine (Lantus) in patients with type 2 diabetes

Treatments for women with gestational diabetes mellitus: an overview of Cochrane systematic reviews

BACKGROUND

Successful treatments for gestational diabetes mellitus (GDM) have the potential to improve health outcomes for women with GDM and their babies.

OBJECTIVES

To provide a comprehensive synthesis of evidence from Cochrane systematic reviews of the benefits and harms associated with interventions for treating GDM on women and their babies.

METHODS

We searched the Cochrane Database of Systematic Reviews (5 January 2018) for reviews of treatment/management for women with GDM. Reviews of pregnant women with pre-existing diabetes were excluded.Two overview authors independently assessed reviews for inclusion, quality (AMSTAR; ROBIS), quality of evidence (GRADE), and extracted data.

MAIN RESULTS

We included 14 reviews. Of these, 10 provided relevant high-quality and low-risk of bias data (AMSTAR and ROBIS) from 128 randomised controlled trials (RCTs), 27 comparisons, 17,984 women, 16,305 babies, and 1441 children. Evidence ranged from high- to very low-quality (GRADE). Only one effective intervention was found for treating women with GDM.EffectiveLifestyle versus usual careLifestyle intervention versus usual care probably reduces large-for-gestational age (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.50 to 0.71; 6 RCTs, N = 2994; GRADE moderate-quality).PromisingNo evidence for any outcome for any comparison could be classified to this category.Ineffective or possibly harmful Lifestyle versus usual careLifestyle intervention versus usual care probably increases the risk of induction of labour (IOL) suggesting possible harm (average RR 1.20, 95% CI 0.99 to 1.46; 4 RCTs, N = 2699; GRADE moderate-quality).Exercise versus controlExercise intervention versus control for return to pre-pregnancy weight suggested ineffectiveness (body mass index, BMI) MD 0.11 kg/m², 95% CI -1.04 to 1.26; 3 RCTs, N = 254; GRADE moderate-quality).Insulin versus oral therapyInsulin intervention versus oral therapy probably increases the risk of IOL suggesting possible harm (RR 1.3, 95% CI 0.96 to 1.75; 3 RCTs, N = 348; GRADE moderate-quality).Probably ineffective or harmful interventionsInsulin versus oral therapyFor insulin compared to oral therapy there is probably an increased risk of the hypertensive disorders of pregnancy (RR 1.89, 95% CI 1.14 to 3.12; 4 RCTs, N = 1214; GRADE moderate-quality).InconclusiveLifestyle versus usual careThe evidence for childhood adiposity kg/m² (RR 0.91, 95% CI 0.75 to 1.11; 3 RCTs, N = 767; GRADE moderate-quality) and hypoglycaemia was inconclusive (average RR 0.99, 95% CI 0.65 to 1.52; 6 RCTs, N = 3000; GRADE moderate-quality).Exercise versus controlThe evidence for caesarean section (RR 0.86, 95% CI 0.63 to 1.16; 5 RCTs, N = 316; GRADE moderate quality) and perinatal death or serious morbidity composite was inconclusive (RR 0.56, 95% CI 0.12 to 2.61; 2 RCTs, N = 169; GRADE moderate-quality).Insulin versus oral therapyThe evidence for the following outcomes was inconclusive: pre-eclampsia (RR 1.14, 95% CI 0.86 to 1.52; 10 RCTs, N = 2060), caesarean section (RR 1.03, 95% CI 0.93 to 1.14; 17 RCTs, N = 1988), large-for-gestational age (average RR 1.01, 95% CI 0.76 to 1.35; 13 RCTs, N = 2352), and perinatal death or serious morbidity composite (RR 1.03; 95% CI 0.84 to 1.26; 2 RCTs, N = 760). GRADE assessment was moderate-quality for these outcomes.Insulin versus dietThe evidence for perinatal mortality was inconclusive (RR 0.74, 95% CI 0.41 to 1.33; 4 RCTs, N = 1137; GRADE moderate-quality).Insulin versus insulinThe evidence for insulin aspart versus lispro for risk of caesarean section was inconclusive (RR 1.00, 95% CI 0.91 to 1.09; 3 RCTs, N = 410; GRADE moderate quality).No conclusions possibleNo conclusions were possible for: lifestyle versus usual care (perineal trauma, postnatal depression, neonatal adiposity, number of antenatal visits/admissions); diet versus control (pre-eclampsia, caesarean section); myo-inositol versus placebo (hypoglycaemia); metformin versus glibenclamide (hypertensive disorders of pregnancy, pregnancy-induced hypertension, death or serious morbidity composite, insulin versus oral therapy (development of type 2 diabetes); intensive management versus routine care (IOL, large-for-gestational age); post- versus pre-prandial glucose monitoring (large-for-gestational age). The evidence ranged from moderate-, low- and very low-quality.

AUTHORS' CONCLUSIONS

Currently there is insufficient high-quality evidence about the effects on health outcomes of relevance for women with GDM and their babies for many of the comparisons in this overview comparing treatment interventions for women with GDM. Lifestyle changes (including as a minimum healthy eating, physical activity and self-monitoring of blood sugar levels) was the only intervention that showed possible health improvements for women and their babies. Lifestyle interventions may result in fewer babies being large. Conversely, in terms of harms, lifestyle interventions may also increase the number of inductions. Taking insulin was also associated with an increase in hypertensive disorders, when compared to oral therapy. There was very limited information on long-term health and health services costs. Further high-quality research is needed.

Pharmacokinetic and pharmacodynamic evaluation of insulin dissolving microneedles in dogs

BACKGROUND

This study tested the hypothesis that dissolving microneedles are a useful transdermal drug delivery system (TDDS) for insulin.

METHODS

Insulin was loaded on a patch (1.0 cm2) that had 100 dissolving microneedles with chondroitin sulfate by microfabrication technology. Pharmacodynamic evaluation was performed by applying two or four patches to the shaved abdominal skin of dogs, and blood samples were collected for 360 min to measure plasma glucose and insulin levels. In diffusion experiment, microneedles containing fluorescein isothiocyanate-insulin and/or Evans blue were administered to the rat skin, and the diffusion rates of tracers were recorded.

RESULTS

The mean length, diameter of basement, and drug-loaded space from the top of the microneedles were 492.6 +/- 2.4, 290.0 +/- 3.6, and 316.0 +/- 7.3 microm, respectively. The insulin content was 1.67 +/- 0.17 IU per patch. The time when the minimum plasma glucose level was obtained was 50.0 +/- 8.7 min for two-patch and 82.5 +/- 14.4 min for four-patch studies. A dose-dependent hypoglycemic effect was observed. By comparing the cumulative percentage change in the plasma glucose level between insulin microneedles and solution, the relative physiological availabilities were calculated to be 71.1 +/- 17.8% (for two patches) and 59.3 +/- 4.4% (for four patches). Bioavailabilities of insulin from microneedles were 72.1 +/- 11.6% (for two patches) and 72.4 +/- 8.3% (for four patches). High diffusion rates of fluorescein isothiocyanate-insulin and Evans blue were observed at the administered skin site and correlated well with the high absorption rate of insulin into the systemic circulation. Insulin was stable in dissolving microneedles for 1 month at 4 degrees C; the recovered percentage was 99.2 +/- 13.9%.

CONCLUSIONS

Dissolving microneedles were demonstrated to be a useful TDDS as an immediate-acting insulin preparation.

A randomized clinical trial comparing the effect of basal insulin and inhaled mealtime insulin on glucose variability and oxidative stress

AIM

To assess the effect of three times daily mealtime inhaled insulin therapy compared with once daily basal insulin glargine therapy on 72-h glucose profiles, glucose variability and oxidative stress in type 2 diabetes patients.

METHODS

In an inpatient crossover study, 40 subjects with type 2 diabetes were randomized to receive 9 days of inhaled insulin three times daily before meals or 9 days of glargine administered in the morning before breakfast in a randomized order. During the last 72 h in each phase, glucose was measured with continuous glucose monitoring. Activation of oxidative stress was measured by determining the 15(S)-8-iso-PGF(2alpha)-secretion in 24-h urine samples.

RESULTS

Inhaled insulin improved overall and postprandial glucose control significantly better than insulin glargine (p < 0.0001). There was a trend towards a greater reduction in glucose variability (8-9%) in the inhaled group [p = 0.1430 and p = 0.3298 for mean amplitude of glycaemic excursions (MAGEs) and mean of daily differences respectively]. Oxidative stress, estimated by determining the urinary isoprostane excretion (15(S)-8-iso-PGF(2alpha)), was equally reduced from baseline by both treatments. No correlation was found between glucose variability and oxidative stress in both groups.

CONCLUSIONS

This study showed a mealtime insulin approach to improve glycaemic control more than a basal insulin approach. These findings indicate also that lowering glucose using insulin treatment lowers oxidative stress over time, at least for the study period of 9 days, in type 2 diabetes patients. Contrary to earlier data, we found no correlation between glucose variability (MAGE) and oxidative stress (15(S)-8-iso-PGF(2alpha)) in this study.