Effect of Oral Insulin on Prevention of Diabetes in Relatives of Patients With Type 1 Diabetes

Question  Can oral insulin delay or prevent clinically diagnosed type 1 diabetes?

Findings  In this randomized clinical trial that included 389 participants in the primary analysis who were first- and second-degree relatives of patients with type 1 diabetes, oral insulin compared with placebo did not significantly reduce the risk of diabetes onset over a median of 2.7 years (insulin group, 28.5% and placebo group, 33%; hazard ratio, 0.87).

Meaning  Oral insulin as used in this study was not effective in prevention of type 1 diabetes.

Reference: JAMA. 2017;318(19):1891-1902.


Continuous glucose monitoring in pregnant women with type 1 diabetes (CONCEPTT)


Pregnant women with type 1 diabetes are a high-risk population who are recommended to strive for optimal glucose control, but neonatal outcomes attributed to maternal hyperglycaemia remain suboptimal. Our aim was to examine the effectiveness of continuous glucose monitoring (CGM) on maternal glucose control and obstetric and neonatal health outcomes.


In this multicentre, open-label, randomised controlled trial, we recruited women aged 18–40 years with type 1 diabetes for a minimum of 12 months who were receiving intensive insulin therapy. Participants were pregnant (≤13 weeks and 6 days’ gestation) or planning pregnancy from 31 hospitals in Canada, England, Scotland, Spain, Italy, Ireland, and the USA. We ran two trials in parallel for pregnant participants and for participants planning pregnancy. In both trials, participants were randomly assigned to either CGM in addition to capillary glucose monitoring or capillary glucose monitoring alone. Randomisation was stratified by insulin delivery (pump or injections) and baseline glycated haemoglobin (HbA1c). The primary outcome was change in HbA1c from randomisation to 34 weeks’ gestation in pregnant women and to 24 weeks or conception in women planning pregnancy, and was assessed in all randomised participants with baseline assessments. Secondary outcomes included obstetric and neonatal health outcomes, assessed with all available data without imputation. This trial is registered with ClinicalTrials.gov, number NCT01788527.


Between March 25, 2013, and March 22, 2016, we randomly assigned 325 women (215 pregnant, 110 planning pregnancy) to capillary glucose monitoring with CGM (108 pregnant and 53 planning pregnancy) or without (107 pregnant and 57 planning pregnancy). We found a small difference in HbA1c in pregnant women using CGM (mean difference −0·19%; 95% CI −0·34 to −0·03; p=0·0207). Pregnant CGM users spent more time in target (68% vs 61%; p=0·0034) and less time hyperglycaemic (27% vs 32%; p=0·0279) than did pregnant control participants, with comparable severe hypoglycaemia episodes (18 CGM and 21 control) and time spent hypoglycaemic (3% vs 4%; p=0·10). Neonatal health outcomes were significantly improved, with lower incidence of large for gestational age (odds ratio 0·51, 95% CI 0·28 to 0·90; p=0·0210), fewer neonatal intensive care admissions lasting more than 24 h (0·48; 0·26 to 0·86; p=0·0157), fewer incidences of neonatal hypoglycaemia (0·45; 0·22 to 0·89; p=0·0250), and 1-day shorter length of hospital stay (p=0·0091). We found no apparent benefit of CGM in women planning pregnancy. Adverse events occurred in 51 (48%) of CGM participants and 43 (40%) of control participants in the pregnancy trial, and in 12 (27%) of CGM participants and 21 (37%) of control participants in the planning pregnancy trial. Serious adverse events occurred in 13 (6%) participants in the pregnancy trial (eight [7%] CGM, five [5%] control) and in three (3%) participants in the planning pregnancy trial (two [4%] CGM and one [2%] control). The most common adverse events were skin reactions occurring in 49 (48%) of 103 CGM participants and eight (8%) of 104 control participants during pregnancy and in 23 (44%) of 52 CGM participants and five (9%) of 57 control participants in the planning pregnancy trial. The most common serious adverse events were gastrointestinal (nausea and vomiting in four participants during pregnancy and three participants planning pregnancy).


Use of CGM during pregnancy in patients with type 1 diabetes is associated with improved neonatal outcomes, which are likely to be attributed to reduced exposure to maternal hyperglycaemia. CGM should be offered to all pregnant women with type 1 diabetes using intensive insulin therapy. This study is the first to indicate potential for improvements in non-glycaemic health outcomes from CGM use.


Juvenile Diabetes Research Foundation, Canadian Clinical Trials Network, and National Institute for Health Research.

Reference: The Lancet, Volume 390, No. 10110, p2347–2359, 25 November 2017

ACE Inhibitors and Statins in Adolescents with Type 1 Diabetes


Among adolescents with type 1 diabetes, rapid increases in albumin excretion during puberty precede the development of microalbuminuria and macroalbuminuria, long-term risk factors for renal and cardiovascular disease. We hypothesized that adolescents with high levels of albumin excretion might benefit from angiotensin-converting–enzyme (ACE) inhibitors and statins, drugs that have not been fully evaluated in adolescents.


We screened 4407 adolescents with type 1 diabetes between the ages of 10 and 16 years of age and identified 1287 with values in the upper third of the albumin-to-creatinine ratios; 443 were randomly assigned in a placebo-controlled trial of an ACE inhibitor and a statin with the use of a 2-by-2 factorial design minimizing differences in baseline characteristics such as age, sex, and duration of diabetes. The primary outcome for both interventions was the change in albumin excretion, assessed according to the albumin-to-creatinine ratio calculated from three early-morning urine samples obtained every 6 months over 2 to 4 years, and expressed as the area under the curve. Key secondary outcomes included the development of microalbuminuria, progression of retinopathy, changes in the glomerular filtration rate, lipid levels, and measures of cardiovascular risk (carotid intima–media thickness and levels of high-sensitivity C-reactive protein and asymmetric dimethylarginine).


The primary outcome was not affected by ACE inhibitor therapy, statin therapy, or the combination of the two. The use of an ACE inhibitor was associated with a lower incidence of microalbuminuria than the use of placebo; in the context of negative findings for the primary outcome and statistical analysis plan, this lower incidence was not considered significant (hazard ratio, 0.57; 95% confidence interval, 0.35 to 0.94). Statin use resulted in significant reductions in total, low-density lipoprotein, and non–high-density lipoprotein cholesterol levels, in triglyceride levels, and in the ratio of apolipoprotein B to apolipoprotein A1, whereas neither drug had significant effects on carotid intima–media thickness, other cardiovascular markers, the glomerular filtration rate, or progression of retinopathy. Overall adherence to the drug regimen was 75%, and serious adverse events were similar across the groups.


The use of an ACE inhibitor and a statin did not change the albumin-to-creatinine ratio over time. (Funded by the Juvenile Diabetes Research Foundation and others; AdDIT ClinicalTrials.gov number, NCT01581476.)

Effect of Insulin Degludec vs Insulin Glargine U100 on Hypoglycemia in Patients With Type 1 Diabetes The SWITCH 1 Randomized Clinical Trial

Question  Is the rate of hypoglycemia noninferior or lower with insulin degludec vs insulin glargine U100 in insulin-treated patients with type 1 diabetes?

Findings  In this randomized crossover trial of 501 patients, insulin degludec compared with insulin glargine U100 resulted in a significantly lower rate of overall symptomatic hypoglycemic episodes over a 16-week maintenance period (2201 vs 2463 episodes per 100 patient-years of exposure).

Meaning  Patients with type 1 diabetes treated with insulin degludec, compared with insulin glargine U100, had a reduced risk of overall symptomatic hypoglycemia.

Reference: JAMA. 2017;318(1):33-44.

Incidence Trends of Type 1 and Type 2 Diabetes among Youths, 2002–2012


Diagnoses of type 1 and type 2 diabetes in youths present a substantial clinical and public health burden. The prevalence of these diseases increased in the 2001–2009 period, but data on recent incidence trends are lacking.


We ascertained cases of type 1 and type 2 diabetes mellitus at five study centers in the United States. Denominators (4.9 million youths annually) were obtained from the U.S. Census or health-plan member counts. After the calculation of annual incidence rates for the 2002–2012 period, we analyzed trends using generalized autoregressive moving-average models with 2-year moving averages.


A total of 11,245 youths with type 1 diabetes (0 to 19 years of age) and 2846 with type 2 diabetes (10 to 19 years of age) were identified. Overall unadjusted estimated incidence rates of type 1 diabetes increased by 1.4% annually (from 19.5 cases per 100,000 youths per year in 2002–2003 to 21.7 cases per 100,000 youths per year in 2011–2012, P=0.03). In adjusted pairwise comparisons, the annual rate of increase was greater among Hispanics than among non-Hispanic whites (4.2% vs. 1.2%, P<0.001). Overall unadjusted incidence rates of type 2 diabetes increased by 7.1% annually (from 9.0 cases per 100,000 youths per year in 2002–2003 to 12.5 cases per 100,000 youths per year in 2011–2012, P<0.001 for trend across race or ethnic group, sex, and age subgroups). Adjusted pairwise comparisons showed that the relative annual increase in the incidence of type 2 diabetes among non-Hispanic whites (0.6%) was lower than that among non-Hispanic blacks, Asians or Pacific Islanders, and Native Americans (P<0.05 for all comparisons) and that the annual rate of increase among Hispanics differed significantly from that among Native Americans (3.1% vs. 8.9%, P=0.01). After adjustment for age, sex, and race or ethnic group, the relative annual increase in the incidence of type 1 diabetes was 1.8% (P<0.001) and that of type 2 diabetes was 4.8% (P<0.001).


The incidences of both type 1 and type 2 diabetes among youths increased significantly in the 2002–2012 period, particularly among youths of minority racial and ethnic groups. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and the Centers for Disease Control and Prevention.)

N Engl J Med 2017; 376:1419-1429

Mortality and Cardiovascular Disease in Type 1 and Type 2 Diabetes


Long-term trends in excess risk of death and cardiovascular outcomes have not been extensively studied in persons with type 1 diabetes or type 2 diabetes.


We included patients registered in the Swedish National Diabetes Register from 1998 through 2012 and followed them through 2014. Trends in deaths and cardiovascular events were estimated with Cox regression and standardized incidence rates. For each patient, controls who were matched for age, sex, and county were randomly selected from the general population.


Among patients with type 1 diabetes, absolute changes during the study period in the incidence rates of sentinel outcomes per 10,000 person-years were as follows: death from any cause, −31.4 (95% confidence interval [CI], −56.1 to −6.7); death from cardiovascular disease, −26.0 (95% CI, −42.6 to −9.4); death from coronary heart disease, −21.7 (95% CI, −37.1 to −6.4); and hospitalization for cardiovascular disease, −45.7 (95% CI, −71.4 to −20.1). Absolute changes per 10,000 person-years among patients with type 2 diabetes were as follows: death from any cause, −69.6 (95% CI, −95.9 to −43.2); death from cardiovascular disease, −110.0 (95% CI, −128.9 to −91.1); death from coronary heart disease, −91.9 (95% CI, −108.9 to −75.0); and hospitalization for cardiovascular disease, −203.6 (95% CI, −230.9 to −176.3). Patients with type 1 diabetes had roughly 40% greater reduction in cardiovascular outcomes than controls, and patients with type 2 diabetes had roughly 20% greater reduction than controls. Reductions in fatal outcomes were similar in patients with type 1 diabetes and controls, whereas patients with type 2 diabetes had smaller reductions in fatal outcomes than controls.


In Sweden from 1998 through 2014, mortality and the incidence of cardiovascular outcomes declined substantially among persons with diabetes, although fatal outcomes declined less among those with type 2 diabetes than among controls. (Funded by the Swedish Association of Local Authorities and Regions and others.)

Relative effectiveness of insulin pump treatment over multiple daily injections and structured education during flexible intensive insulin treatment for type 1 diabetes: cluster randomised trial (REPOSE)

Objective To compare the effectiveness of insulin pumps with multiple daily injections for adults with type 1 diabetes, with both groups receiving equivalent training in flexible insulin treatment.

Design Pragmatic, multicentre, open label, parallel group, cluster randomised controlled trial (Relative Effectiveness of Pumps Over MDI and Structured Education (REPOSE) trial).

Setting Eight secondary care centres in England and Scotland.

Participants Adults with type 1 diabetes who were willing to undertake intensive insulin treatment, with no preference for pumps or multiple daily injections. Participants were allocated a place on established group training courses that taught flexible intensive insulin treatment (“dose adjustment for normal eating,” DAFNE). The course groups (the clusters) were then randomly allocated in pairs to either pump or multiple daily injections.

Interventions Participants attended training in flexible insulin treatment (using insulin analogues) structured around the use of pump or injections, followed for two years.

Main outcome measures The primary outcomes were a change in glycated haemoglobin (HbA1c) values (%) at two years in participants with baseline HbA1c value of ≥7.5% (58 mmol/mol), and the proportion of participants achieving an HbA1c value of <7.5%. Secondary outcomes included body weight, insulin dose, and episodes of moderate and severe hypoglycaemia. Ancillary outcomes included quality of life and treatment satisfaction.

Results 317 participants (46 courses) were randomised (156 pump and 161 injections). 267 attended courses and 260 were included in the intention to treat analysis, of which 235 (119 pump and 116 injection) had baseline HbA1c values of ≥7.5%. Glycaemic control and rates of severe hypoglycaemia improved in both groups. The mean change in HbA1c at two years was −0.85% with pump treatment and −0.42% with multiple daily injections. Adjusting for course, centre, age, sex, and accounting for missing values, the difference was −0.24% (−2.7 mmol/mol) in favour of pump users (95% confidence interval −0.53 to 0.05, P=0.10). Most psychosocial measures showed no difference, but pump users showed greater improvement in treatment satisfaction and some quality of life domains (dietary freedom and daily hassle) at 12 and 24 months.

Conclusions Both groups showed clinically relevant and long lasting decreases in HbA1c, rates of severe hypoglycaemia, and improved psychological measures, although few participants achieved glucose levels currently recommended by national and international guidelines. Adding pump treatment to structured training in flexible intensive insulin treatment did not substantially enhance educational benefits on glycaemic control, hypoglycaemia, or psychosocial outcomes in adults with type 1 diabetes. These results do not support a policy of providing insulin pumps to adults with poor glycaemic control until the effects of training on participants’ level of engagement in intensive self management have been determined.

Trial registration Current Controlled Trials ISRCTN61215213.

BMJ 2017;356:j1285