A core outcome set for the treatment of pregnant women with pregestational diabetes: an international consensus study

Objective

To develop a core outcome set (COS) for randomised controlled trials (RCTs) evaluating the effectiveness of interventions for the treatment of pregnant women with pregestational diabetes mellitus (PGDM).

Design

A consensus developmental study.

Setting

International.

Population

Two hundred and five stakeholders completed the first round.

Methods

The study consisted of three components. (1) A systematic review of the literature to produce a list of outcomes reported in RCTs assessing the effectiveness of interventions for the treatment of pregnant women with PGDM. (2) A three-round, online eDelphi survey to prioritise these outcomes by international stakeholders (including healthcare professionals, researchers and women with PGDM). (3) A consensus meeting where stakeholders from each group decided on the final COS.

Main outcome measures

All outcomes were extracted from the literature.

Results

We extracted 131 unique outcomes from 67 records meeting the full inclusion criteria. Of the 205 stakeholders who completed the first round, 174/205 (85%) and 165/174 (95%) completed rounds 2 and 3, respectively. Participants at the subsequent consensus meeting chose 19 outcomes for inclusion into the COS: trimester-specific haemoglobin A1c, maternal weight gain during pregnancy, severe maternal hypoglycaemia, diabetic ketoacidosis, miscarriage, pregnancy-induced hypertension, pre-eclampsia, maternal death, birthweight, large for gestational age, small for gestational age, gestational age at birth, preterm birth, mode of birth, shoulder dystocia, neonatal hypoglycaemia, congenital malformations, stillbirth and neonatal death.

Conclusions

This COS will enable better comparison between RCTs to produce robust evidence synthesis, improve trial reporting and optimise research efficiency in studies assessing treatment of pregnant women with PGDM.

165 key stakeholders have developed #Treatment #CoreOutcomes in pregnant women with #diabetes existing before pregnancy.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Skeletal findings in the first 12 months following initiation of glucocorticoid therapy for pediatric nephrotic syndrome

Incident vertebral fractures and lumbar spine bone mineral density (BMD) were assessed in the 12 months following glucocorticoid initiation in 65 children with nephrotic syndrome. The incidence of vertebral fractures was low at 12 months (6 %) and most patients demonstrated recovery in BMD Z-scores by this time point.

INTRODUCTION

Vertebral fracture (VF) incidence following glucocorticoid (GC) initiation has not been previously reported in pediatric nephrotic syndrome.

METHODS

VF was assessed on radiographs (Genant method); lumbar spine bone mineral density (LS BMD) was evaluated by dual-energy X-ray absorptiometry.

RESULTS

Sixty-five children were followed to 12 months post-GC initiation (median age, 5.4 years; range, 2.3-17.9). Three of 54 children with radiographs (6 %; 95 % confidence interval (CI), 2-15 %) had incident VF at 1 year. The mean LS BMD Z-score was below the healthy average at baseline (mean ± standard deviation (SD), -0.5 ± 1.1; p = 0.001) and at 3 months (-0.6 ± 1.1; p < 0.001), but not at 6 months (-0.3 ± 1.3; p = 0.066) or 12 months (-0.3 ± 1.2; p = 0.066). Mixed effect modeling showed a significant increase in LS BMD Z-scores between 3 and 12 months (0.22 SD; 95 % CI, 0.08 to 0.36; p = 0.003). A subgroup (N = 16; 25 %) had LS BMD Z-scores that were ≤-1.0 at 12 months. In these children, each additional 1,000 mg/m(2) of GC received in the first 3 months was associated with a decrease in LS BMD Z-score by 0.39 at 12 months (95 % CI, -0.71 to -0.07; p = 0.017).

CONCLUSIONS

The incidence of VF at 1 year was low and LS BMD Z-scores improved by 12 months in the majority. Twenty-five percent of children had LS BMD Z-scores ≤-1.0 at 12 months. In these children, LS BMD Z-scores were inversely associated with early GC exposure, despite similar GC exposure compared to the rest of the cohort.

Skeletal findings in children recently initiating glucocorticoids for the treatment of nephrotic syndrome

SUMMARY

Eighty children with nephrotic syndrome underwent lumbar spine densitometry and vertebral morphometry soon after glucocorticoid initiation. We found an inverse relationship between glucocorticoid exposure and spine areal bone mineral density (BMD) Z-score and a low rate of vertebral deformities (8%).

INTRODUCTION

Vertebral fractures are an under-recognized complication of childhood glucocorticoid-treated illnesses. Our goal was to study the relationships among glucocorticoid exposure, lumbar spine areal BMD (LS BMD), and vertebral shape in glucocorticoid-treated children with new-onset nephrotic syndrome.

METHODS

Lateral thoracolumbar spine radiography and LS BMD were performed in 80 children with nephrotic syndrome (median age 4.4 years; 46 boys) within the first 37 days of glucocorticoid therapy. Genant semiquantitative grading was used as the primary method for vertebral morphometry; the algorithm-based qualitative (ABQ) method was used for secondary vertebral deformity analysis.

RESULTS

Six of the 78 children with usable radiographs (8%; 95% confidence interval 4 to 16%) manifested a single Genant grade 1 deformity each. All deformities were mild anterior wedging (two at each of T6, T7, and T8). Four of the 78 children (5%; 95% confidence interval 2 to 13%) showed one ABQ sign of fracture each (loss of endplate parallelism; two children at T6 and two at T8). Two of the children with ABQ signs also had a Genant grade 1 deformity in the same vertebral body. None of the children with a Genant or ABQ deformity reported back pain. An inverse relationship was identified between LS BMD Z-score and glucocorticoid exposure.

CONCLUSIONS

Although we identified an inverse relationship between steroid exposure and LS BMD soon after glucocorticoid initiation for childhood nephrotic syndrome, there was only a low rate of vertebral deformities. The clinical significance of these findings requires further study.

Treatment of familial hypercholesterolemia in children and adolescents: effect of lovastatin. Canadian Lovastatin in Children Study Group

OBJECTIVE

Familial hypercholesterolemia (FH), an inherited autosomal dominant disorder of lipoprotein metabolism, is associated with premature atherosclerosis. The recommended pediatric therapy consists of dietary intervention and, when necessary, treatment with bile acid-binding resins. However, compliance has been poor in many children. Therefore, our objectives were to determine the efficacy, safety, and tolerance of the short-term use of lovastatin, a 3-hydroxy 3-methylglutaryl coenzyme A reductase inhibitor, in the control of severe FH in a male pediatric population and to evaluate the dose-response relationship.

METHODS

Sixty-nine male patients with FH 12.9 +/- 2.4 years of age (mean +/- SD) participated in this multicenter, randomized, double-blind trial. After a 4-week placebo period, the patients were allocated to four treatment groups (lovastatin 10, 20, 30, 40 mg/d) for 8 weeks. Plasma lipid and apolipoprotein (Apo) concentrations were measured every 2 weeks. Clinical and laboratory evidence of adverse events was monitored periodically throughout the study.

RESULTS

All lovastatin doses reduced total cholesterol (-17% to -29%), low density lipoprotein cholesterol (-21% to -36%), and ApoB (-19% to -28%) concentrations. A dose-response relationship was seen, and between-group comparisons showed that results were significantly improved up to a dose of 30 mg/d. We observed a 7% increase in high-density lipoprotein cholesterol and a 4% increase in ApoA1 concentrations. The medication was well tolerated by all patients. No serious clinical adverse experience was reported. Lovastatin increased aspartate aminotransferase concentrations, but there was no evidence of a dose-response relationship, and no value exceeded two times the upper limit of normal. No significant change in alanine aminotransferase was observed. Three patients had marked (more than three times the upper limit of normal) asymptomatic elevations in their creatine kinase values, which returned spontaneously to normal, and no action was required regarding the drug.

Placental weight in diabetic pregnancies

The placenta from 30 women with diabetes mellitus were examined and weighed at delivery. Nineteen of these were from women with overt and eleven from women with gestational diabetes. Eleven placentae from normal pregnancies served as controls. There was no difference between the mean +/- s.d. placental weight for the diabetic group and the control group (609 +/- 148 versus 591 +/- 93 g, NS). The mean placental weight ratios for the diabetic group and the control group were also similar (0.98 +/- 0.23 versus 0.89 +/- 0.15, NS). Moreover, there was no difference between the weights and weight ratios of placentae from women with overt (622 +/- 173 g, 1.02 +/- 0.27) and those with gestational diabetes (586 +/- 90 g, versus 0.90 +/- 0.13). Placental weights correlated with birthweights (r = 0.70, P less than 0.01) and with skinfold thickness measurements fo the infants (r = 0.40, P less than 0.05), but neither with gestational ages (r = 0.15, NS) nor with maternal glycosylated haemoglobin levels in the third trimester (r = 0.24, NS). Among the women with overt diabetes, placental weights were greater in those in White's class B and C than those in class D and R (689 +/- 143 versus 530 +/- 177 g; P less than 0.05). In general, placentae from well controlled diabetic patients were not heavier than those from normal pregnant women, although there was an increase in placental weight in White's class B and C, as compared with those in class D and R.

Factors affecting insulin antibody binding in children with insulin-dependent diabetes mellitus

We measured insulin antibody binding in 2 groups of patients: Study 1, 32 children with newly diagnosed IDDM before onset of insulin therapy, and, in 20 of these, 10 days, 1, 3, and 6 months after beginning therapy; and Study 2, 35 children with long-standing IDDM, 20 of whom had free insulin concentrations measured before, and for 2 hours following subcutaneous injection of 0.25 U/kg regular insulin. Almost 35% of new onset subjects had insulin antibody binding above control levels. In those studied prospectively, binding increased significantly with time. Pre-treatment binding did not correlate with later insulin antibody binding nor metabolic control. In Study 1 we have confirmed previous studies showing abnormally high insulin antibody binding in children with IDDM pre-treatment. We have been unable to demonstrate a relationship between this binding and that found 6 months after initiation of therapy. In Study 2, we have shown that insulin antibody binding is not related to either the level of metabolic control or the rate of rise of free insulin levels in children with IDDM.

Residual beta-cell function in children with type 1 diabetes: measurement and impact on glycemic control

We studied residual beta-cell function in 84 children with IDDM to assess (1) relationship between basal and stimulated C-peptide concentrations; (2) reproducibility of testing (Group 1, n = 20); (3) the effect of exogenous insulin on test interpretation (Group II, n = 20); and (4) impact on metabolic control. Sustacal (a mixed liquid meal) was utilized as the test stimulus. In C-peptide positive subjects (n = 44) there was a strong correlation between basal and peak C-peptide concentrations (r = 0.88, p less than 0.001). In Group 1 subjects, Sustacal proved to be a highly reproducible test stimulus producing identical results on two tests 7-14 days apart. The results of the tests were not affected by the administration of subcutaneous regular insulin prior to the second test in Group II. Peak C-peptide correlated inversely with HbA1, insulin dose, and disease duration (r = -0.29, -0.40, and -0.33 respectively, p less than 0.05) and positively with age (r = 0.34, p less than 0.05). We conclude that Sustacal is a highly reproducible stimulus to residual beta-cell function in IDDM and is not affected by exogenous insulin. This residual insulin secretion has a small but significant effect on glycemic control.

Factors affecting and patterns of residual insulin secretion during the first year of type 1 (insulin-dependent) diabetes mellitus in children

We measured serum C-peptide, glucose, pH, islet antibodies and insulin antibody binding at diagnosis in 84 children with Type 1 (insulin-dependent) diabetes. In a subgroup of 33 children, residual insulin secretion (basal and peak C-peptide response to Sustacal), insulin antibody binding and HbA1c were measured at 10 days, 1, 3, 6 and 12 months. At presentation C-peptide correlated positively with age at onset and negatively with the blood glucose concentration. Median C-peptide concentration at diagnosis was low, rose significantly (p less than 0.05) at 10 days, reached a maximum at 1-3 months and declined gradually to 1 year. C-peptide concentration both at diagnosis and at 10 days correlated with that at 3 and 6 months. Of the factors investigated, only age (p less than 0.005) and sex (higher in females, p less than 0.01) were found to have a significant influence on basal/peak C-peptide levels throughout the first year. In particular there was no relationship between C-peptide, HbA1c and insulin dose during this period. A peak C-peptide response at 3-6 months greater than/less than 0.32 nmol/l was used to divide the group into two: 16 had a peak response less than 0.32 nmol/l (low secretors) while in 17, the peak C-peptide was greater than 0.32 nmol/l (high secretors). While the low secretors had significantly (p less than 0.05) lower C-peptide levels during the first year, there were no differences between low and high secretors in HbA1c or insulin dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Dietary triggers of insulin-dependent diabetes in the BB rat

Environmental "triggers" (including viruses, toxins and dietary factors) have been implicated in the pathogenesis of insulin-dependent diabetes mellitus. Data have suggested a possible role for cow's milk protein (CMP) as a trigger of diabetes. To study this further, 86 BB rats were divided into 2 groups during the weaning period (days 13-25): Group A received rat chow without CMP; Group B, rat chow with 1% CMP added. Each group was subdivided afterwards into 2: Groups A1 and B1 received chow without CMP; Groups A2 and B2, chow with CMP. Animals weaned with chow containing CMP (B1 and B2) had a higher incidence of diabetes (66%) than those weaned without (A1 and A2; 29%, p less than 0.001). The incidence in both B1 and B2 was significantly greater than in either A1 or A2 (p less than 0.05). The highest incidence of diabetes occurred in male rats weaned on rat chow with CMP (90%), the incidence being significantly higher than female rats weaned with (43%) or without CMP (18%) and males weaned without CMP (39%). Thus, it appears that (a) the presence of cow's milk protein in the diet increases the incidence of diabetes in the BB rat; (b) the critical time for exposure to CMP appears to be the weaning period; and (c) male rats appear to be more susceptible to the development of diabetes than female rats, when exposed to this trigger. This supports the hypothesis that dietary triggers may play an important role in the expression of diabetes in the susceptible host and that its prevalent action occurs early in life.

Residual beta-cell function in children with IDDM: reproducibility of testing and factors influencing insulin secretory reserve

Reproducibility of C-peptide secretion was assessed in 20 children (group 1) by their responses to two Sustacal- (a mixed liquid meal) stimulation tests performed 7-14 days apart. For the 12 C-peptide-positive children (basal C-peptide greater than or equal to 0.03 pmol/ml) there were no differences in the basal or stimulated values between tests 1 and 2. The effect of exogenous insulin on C-peptide secretion was assessed in 20 other children (group 2) by their responses to two Sustacal tests, one test without and one with soluble insulin (0.25 U/kg) injected subcutaneously before testing. Eleven children were C-peptide positive and had no differences in C-peptide response between tests 1 and 2. The results from test 1 in groups 1 and 2 were combined with those from 44 others undergoing a single Sustacal test (group 3, N = 84). There was a close correlation between basal and peak C-peptide concentrations in the 44 C-peptide-positive children (r = .88, P less than .001). Peak C-peptide concentrations correlated inversely with HbA1 (r = -.29, P less than .01), insulin dose in units per kilogram (r = -.40, P less than .001), and duration of diabetes (r = .33, P less than .001) and positively with age at onset of diabetes (r = .34, P less than .001). The C-peptide-positive children had reduced glucose response to Sustacal, lower HbA1 concentration, lower insulin requirement, later age of onset, and shorter duration of diabetes than children who were C-peptide negative.

Randomized controlled trial of very early continuous distending pressure in the management of preterm infants

Application of continuous distending pressure at birth (very early CDP) should stabilize the immature airways and reduce the severity of respiratory distress syndrome (RDS) in preterm infants. Eighty-two preterm infants of less than 32 weeks gestation were randomly assigned at birth to early treatment group (TG), in which CDP of 6 cm water pressure was applied at birth by the nasopharyngeal route (NP-CDP), or to control group (CG), in which CDP was applied when indicated for established criteria (pO2 less than 50 mmHg in FiO2 greater than 0.5). Characteristics of the infants in the two groups were comparable. No statistically significant difference between the two groups was found in the incidence of RDS. The course of RDS, and oxygen and ventilatory requirements also did not appear to be changed. In blood gas parameters of most of the time frames, no significant difference was found between the two groups when the results were analyzed according to the assigned group. When the results were analyzed separately for the infants who developed RDS, infants in TG appear to have fared worse from the therapy in terms of oxygenation, as indicated by significantly higher FiO2 (P less than 0.01) and lower a/A (P less than 0.01) values on the third day of the course of RDS, as compared to infants in CG. The incidence of complications was comparable in the two groups. Four infants from TG (9.3%) and one from CG (2.6%) died (P = NS). We conclude that VECDP by nasopharyngeal route does not reduce the incidence of RDS and does not appear to improve the outcome and may worsen the severity of RDS when compared to application of CDP for established criteria.

Subclinical diabetes mellitus in the BB rat

The spontaneously diabetic BB Wistar rat is a well recognized animal model for the study of insulin-dependent diabetes mellitus (IDDM). Previously we have noted hyperglycemia and insulitis in BB rats without clinical diabetes. 121 rats were studied prospectively. 43 (36%) were normal and 64 (52%) developed IDDM suspected by the presence of glycosuria and acute weight loss, and confirmed with pancreatic histology. In the remaining 14 (12%) animals, pancreatic histology was also abnormal, varying from mild insulitis only to moderate insulitis and beta-cell degranulation. Since these rats gained weight normally, had no glycosuria, or hyperglycemia they were designated as having subclinical diabetes. At death, their plasma-insulin concentrations and the amount of extracted pancreatic insulin was intermediate between that of the normal and diabetic group (p less than 0.001). We have identified a group of rats with pancreatic features of diabetes but no clinical expression. Further investigation of this syndrome may reveal clinical, immunological or histological features which protect these animals from the development of overt disease.

The relationship of metabolic control to growth and pubertal development in children with insulin-dependent diabetes

Growth and pubertal development were studied in 122 children aged 13.4 +/- 2.9 yr (mean +/- SD) with IDDM of 6.1 +/- 3.8 yr duration. Height and weight, pubertal status, insulin dose (u/kg), frequency of insulin administration and HbA1 were measured every 3 months for a minimum period of 1 yr for each child. The mean and distribution of height and height velocity percentiles were normal for boys and girls. The mean weight percentile for boys was increased (62 +/- 27, p less than 0.01), but was normal for girls. The mean and distribution of weight velocity percentiles were normal for both sexes. The mean and distribution of age of onset of Tanner 2 in both boys (11.9 +/- 1.4 yr) and girls (11.2 +/- 1.3) was normal, as was the age of menarche (13.2 +/- 1.2 yr). The mean HbA1 level was 11.1 +/- 2.0% (normal less than 7.5%). There was no correlation of mean HbA1 levels (calculated from 4 or more measurements for each child) with height velocity or with weight velocity percentiles or with mean height or weight percentiles. These results indicate that diabetic control, as reflected by HbA1 levels, was not a major determinant of growth in this group of children with IDDM, who displayed normal growth patterns and pubertal development despite a wide range of HbA1 levels. Normal growth may not reflect optimal metabolic control but "average" control.

Self-monitoring of blood glucose: how accurate are children with diabetes at reading chemstrip bG?

Accuracy of self-monitoring of blood glucose (SMBG) using Chemstrip bG (Bio-Dynamics, Indianapolis, Indiana) was studied in 90 randomly selected children with insulin-dependent diabetes mellitus (IDDM). For 28 children (mean age 8.3 +/- 3.6 yr) a parent routinely read the Chemstrip at home. The remaining 62 children (mean age 13.7 +/- 2.8 yr) read the Chemstrip themselves. Each child or parent analyzed 20 capillary blood samples using Chemstrips and answered a questionnaire on SMBG. The accuracy of SMBG of the group was high (mean correlation coefficient = 0.89 +/- 0.05), but consistency of measurement was variable (mean standard deviation = 1.90 +/- 0.57) and there was a general tendency to underread Chemstrips (mean y-intercept = 1.05 +/- 1.48; mean slope = 0.80 +/- 0.17). For each subject, 0-65% (mean of 34%) of readings were within 10% of the laboratory measurement, and 17-100% (mean 68%) within 20%. These results indicate that most subjects were fairly accurate in reading Chemstrips; however, analysis of accuracy is useful in identifying individuals who are inaccurate or inconsistent in SMBG. Continuing supervision of SMBG is necessary in children with IDDM.