Use of continuous subcutaneous insulin infusion versus multiple daily injections in emerging adults with type 1 diabetes is associated with better clinical engagement but not glycaemic control

BACKGROUND

Limited studies have compared outcomes between emerging adults with type 1 diabetes mellitus (T1D) attending a diabetes transition support programme using multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII).

AIMS

To assess glycaemic control and service utilisation in emerging adults with T1D on MDI or CSII attending a young adult diabetes clinic (YAC).

METHODS

A retrospective cohort analysis was conducted from January 2013 to December 2015. Data collected included clinic visits per year, after-hours mobile telephone use, diabetic ketoacidosis (DKA) admissions and all HbA1c levels. Independent t-test was used to compare continuous variables whilst Pearson's Chi-squared test was used for categorical variables. Linear mixed effects models explored mean changes in HbA1c levels over time.

RESULTS

Over 3 years, 318 youth with T1D (176 MDI, 121 CSII, 21 switched from MDI to CSII) attended our YAC. Aggregated mean HbA1c levels remained similar between modalities (CSII 9.1% vs MDI 9.3%; P = 0.23); however, mean change in HbA1c at 3 years was significantly increased in CSII users at 0.55% (95% CI 0.15-0.95; P < 0.01) compared with no significant change in MDI users. Clinic visits per year were improved in CSII users (CSII 2.8 vs MDI 2.5; P = 0.02), while DKA admissions remained similar between MDI and CSII users (3.6 admissions per 100 patient-years).

CONCLUSION

In our YAC cohort, glycaemic control in CSII and MDI users was similar but well below recommended international glycaemic targets (HbA1c level < 7.0%). Despite increased clinical engagement occurring in CSII users, glycaemic deterioration was observed over the 3 years.

Universal Subsidized Continuous Glucose Monitoring Funding for Young People With Type 1 Diabetes: Uptake and Outcomes Over 2 Years, a Population-Based Study

OBJECTIVE

Continuous glucose monitoring (CGM) is increasingly used in type 1 diabetes management; however, funding models vary. This study determined the uptake rate and glycemic outcomes following a change in national health policy to introduce universal subsidized CGM funding for people with type 1 diabetes aged <21 years.

RESEARCH DESIGN AND METHODS

Longitudinal data from 12 months before the subsidy until 24 months after were analyzed. Measures and outcomes included age, diabetes duration, HbA1c, episodes of diabetic ketoacidosis and severe hypoglycemia, insulin regimen, CGM uptake, and percentage CGM use. Two data sources were used: the Australasian Diabetes Database Network (ADDN) registry (a prospective diabetes database) and the National Diabetes Service Scheme (NDSS) registry that includes almost all individuals with type 1 diabetes nationally.

RESULTS

CGM uptake increased from 5% presubsidy to 79% after 2 years. After CGM introduction, the odds ratio (OR) of achieving the HbA1c target of <7.0% improved at 12 months (OR 2.5, P < 0.001) and was maintained at 24 months (OR 2.3, P < 0.001). The OR for suboptimal glycemic control (HbA1c ≥9.0%) decreased to 0.34 (P < 0.001) at 24 months. Of CGM users, 65% used CGM >75% of time, and had a lower HbA1c at 24 months compared with those with usage <25% (7.8 ± 1.3% vs. 8.6 ± 1.8%, respectively, P < 0.001). Diabetic ketoacidosis was also reduced in this group (incidence rate ratio 0.49, 95% CI 0.33-0.74, P < 0.001).

CONCLUSIONS

Following the national subsidy, CGM use was high and associated with sustained improvement in glycemic control. This information will inform economic analyses and future policy and serve as a model of evaluation diabetes technologies.

Insulin resistance in type 1 diabetes managed with metformin (INTIMET): Study protocol of a double-blind placebo-controlled, randomised trial

BACKGROUND

Insulin resistance is an under-recognised metabolic defect and cardiovascular risk factor in Type 1 diabetes. Whether metformin improves hepatic, muscle or adipose tissue insulin sensitivity has not been studied in adults with Type 1 diabetes. We initiated the INTIMET study (INsulin resistance in Type 1 diabetes managed with METformin), a double-blind randomised, placebo-controlled trial to measure the effect of metformin on tissue-specific insulin resistance in adults with Type 1 diabetes.

METHODS

We will study 40 adults aged 20-55 years with Type 1 diabetes (HbA1c ≤ 80 mmol/mol [9.5%], fasting C-peptide <0.3 nmol/L) and 20 age-, gender- and body mass index (BMI)-matched controls. Insulin sensitivity will be determined by the two-step hyperinsulinaemic-euglycaemic clamp method with deuterated glucose to document liver, muscle and adipose insulin sensitivity. Subjects with Type 1 diabetes will be randomised to metformin extended-release 1500 mg daily or matched placebo for 26 weeks. The primary outcome is change in hepatic insulin sensitivity, assessed by change in basal rate of appearance (Ra) of glucose and suppression of endogenous glucose production (EGP) during the low-dose stage of the clamp.

CONCLUSION

The INTIMET study is the first clinical trial to quantify the impact of metformin on liver, muscle and adipose insulin resistance in adults with Type 1 diabetes. This study may identify factors that predict an individual's response to metformin in Type 1 diabetes.

TRIAL REGISTRATION

ACTRN12619001440112.

MON-LB113 Insulin Resistance in Type 1 Diabetes Managed With Metformin (INTIMET): Rationale and Study Design of a Randomised Placebo-Controlled Trial

Background: Insulin resistance is an under-recognised cardiovascular risk factor in type 1 diabetes (T1D). Individuals with T1D exhibit insulin resistance relative to those without diabetes. In T1D, tissue-specific insulin resistance (muscle, hepatic, adipose) is likely to partly drive increased cardiovascular risk. Adjunctive metformin improves muscle insulin sensitivity in T1D adolescents, but factors that predict responsiveness remain unknown.Objective: To report the rationale and design of the INTIMET study, a double-blind randomised, placebo-controlled trial of metformin in T1D.Methods: Forty adults aged 20-50 years with T1D, and 20 age- gender- and BMI- matched non-diabetic controls will be studied. T1D inclusion criteria are diagnosis &gt; 10 years, HbA1c 9.5% and fasting C-peptide &lt; 0.3nmol/L. Liver and muscle insulin sensitivity will be determined by the 2-stage hyperinsulinemic (20 and 60 mUm2)-euglycemic (5.5 mmol/L) clamp method with deuterated glucose. Subjects with T1D will be randomised to metformin extended-release 1500mg/d or matched placebo for 26 weeks. The primary endpoint is the change in hepatic insulin sensitivity, measured by suppression of endogenous glucose production (EGP) with the low-dose insulin clamp. Secondary endpoints include change in muscle and adipose tissue insulin sensitivity, arterial stiffness, HbA1c, glucose variability, frequency of hypoglycemia, insulin dose, anthropometry, body composition, lipid profile, liver fat and stiffness. Conclusion: The INTIMET study will quantify muscle, liver and adipose insulin-resistance in T1D, determine whether metformin is effective in improving insulin resistance in T1D and identify factors that predict metformin-responsiveness.

The trial is registered (Australian New Zealand Clinical Trial Registry, ACTRN12619001440112) and is actively recruiting in Sydney, Australia.

Reducing Type 1 Diabetes Mortality: Role for Adjunctive Therapies?

Individuals with type 1 diabetes (T1D) frequently fail to achieve glycemic goals and have excess cardiovascular risk and premature death. Adjunctive agents may play a role in reducing morbidity, mortality, and the adverse sequelae of insulin treatment. A surge in type 2 diabetes drug development has revealed agents with benefits beyond glucose lowering, including cardiovascular risk reduction. Could these benefits translate to T1D? Specific trials for T1D demonstrate substantial hemoglobin (Hb)A1c reductions with sodium glucose cotransporter inhibitors (SGLTis) and glucagon-like peptide (GLP)1 agonists, and modest improvements with metformin, dipeptidyl peptidase-4 inhibitor (DPP4i), and pramlintide. Studies exploring cardiovascular risk reduction are warranted. This review synthesizes the emerging literature for researchers and clinicians treating people with T1D. Challenges in T1D research are discussed.

Health outcomes for youth with type 1 diabetes at 18 months and 30 months post transition from pediatric to adult care

AIMS

To identify (a) determinants of glycated haemoglobin (HbA1c) at 18 and 30 months following transition in young people with Type 1 diabetes mellitus (T1DM) to a youth-specific diabetes service; and to (b) evaluate the impact of the service on acute admissions with diabetic ketoacidosis (DKA) over a 14-year period.

METHODS

An audit of records of youth with T1DM referred from paediatric services to the multidisciplinary transition service at Westmead Hospital, from 2001 to 2012, and followed-up to 2014.

RESULTS

Data from 439 adolescents and young adults (Median age: 18) were analysed. The recommended standard of glycaemic control, HbA1c < 7.5% (58 mmol/mol), was achieved by 23% at baseline, 22% at 18-months, and 20% at 30-month. After adjusting for lag time (>3 months) and diabetes duration (>7 years), glycaemic control at first visit predicted subsequent glycaemic control at 18-month and 30-month follow-up. From 2001 to 2014, only 8.6% were lost to follow-up; admissions and readmissions for DKA reduced from 72% (32/47) to 4% (14/340) (p < 0.001). Furthermore, mean length of stay (LOS) significantly decreased from 6.56 to 2.36 days (p < 0.001).

CONCLUSIONS

Continuing engagement with the multidisciplinary transition service prevented deterioration in HbA1c following transition. Age-appropriate education and regular follow-up prevents DKA admissions and significantly reduced admission LOS.

Ethnicity influences cardiovascular outcomes and complications in patients with type 2 diabetes

AIM

To determine whether cardiovascular outcomes in type 2 diabetes (T2D) differ according to ethnicity, and whether ethnicity influences the effect of gender on these outcomes in Caucasians, East-Southeast-Asians, Middle-Easterners, South-Asians and Pacific-Islanders.

METHODS

We compared demographics, HbA1c, lipid profile, renal function markers, and prevalence of macrovascular and microvascular complications between ethnic groups. Cross-sectional data was prospectively collected from 204 consecutive patients at Westmead Hospital's T2D clinic from April-October 2015. Univariate analysis was performed using chi-squared test for categorical data, and Mann-Whitney-U or Kruskal-Wallis test for continuous data.

RESULTS

Compared to Caucasians, South-Asians were diagnosed younger, were currently younger, had lower body-mass-index (BMI) and better renal function but higher rates of non-ST-elevation myocardial infarction (STEMI, 21.7% versus 3.5%, p<0.05). East-Southeast-Asians had lower BMI but more nephropathy than Caucasians (59% versus 39%, p<0.05). East-Southeast-Asian males had fewer CVD than Caucasians, but this protection was absent in East-Southeast-Asian females. Middle-Easterners had more non-STEMI than Caucasians (5.3% vs 3.5%, p<0.05). Middle-Eastern females were not at lower CVD risk than males. Caucasians had most PVD (20% versus 6%, p<0.05).

CONCLUSIONS

Ethnicity influences rates of diabetes-related complications. Female CVD protection is altered in some groups. Ethnicity should be considered in assessing CVD and complications risk.

Healthcare professional requirements for the care of adult diabetes patients managed with insulin pumps in Australia

BACKGROUND

Healthcare professional (HCP) time supporting insulin pump therapy (IPT) has not been documented, yet it is important in planning and allocating resources for effective care.

AIM

This study aims to determine HCP time spent in IPT patient care to inform resource planning for optimal IPT delivery.

METHODS

Twenty-four Australian adult IPT-experienced institutions (14 government funded, seven private, three both) collected data between April 2012 and January 2013 prospectively, including: patient demographics, HCP classification, purpose of HCP-patient interaction, interaction mode and HCP time with the patient. A subset of patients was tracked from pre-pump education until stable on IPT.

RESULTS

Data on 2577 HCP-adult patient interactions (62% face-to-face, 29% remote, 9% administrative) were collected over 12.2 ± 6.4 weeks for 895 patients; age 35.4 ± 14.2 years; 67% female; 99% type 1 diabetes, representing 25% of all IPT patients of the institutions. Time (hours) spent on IPT interactions per centre per week were: nurses 5.4 ± 2.8, dietitians 0.4 ± 0.2 and doctors 1.0 ± 0.5. IPT starts accounted for 48% of IPT interaction time. The percentage of available diabetes clinic time spent on outpatient IPT interactions was 20.4%, 4.6% and 2.7% for nurses, dietitians and doctors respectively. Fifteen patients tracked from pre-pump to stabilisation over 11.8 ± 4.5 weeks, required a median (range) of 9.2 (3.0-20.9), 2.4 (0.5-6.0) and 1.8 (0.5-5.4) hours per patient from nurses, dietitians and doctors respectively.

CONCLUSIONS

IPT patient care represents a substantial investment in HCP time, particularly for nurses. Funding models for IPT care need urgent review to ensure this now mainstream therapy integrates well into healthcare resources.

Multicenter Australian trial of islet transplantation: improving accessibility and outcomes

Whilst initial rates of insulin independence following islet transplantation are encouraging, long-term function using the Edmonton Protocol remains a concern. The aim of this single-arm, multicenter study was to evaluate an immunosuppressive protocol of initial antithymocyte globulin (ATG), tacrolimus and mycophenolate mofetil (MMF) followed by switching to sirolimus and MMF. Islets were cultured for 24 h prior to transplantation. The primary end-point was an HbA1c of <7% and cessation of severe hypoglycemia. Seventeen recipients were followed for ≥ 12 months. Nine islet preparations were transported interstate for transplantation. Similar outcomes were achieved at all three centers. Fourteen of the 17 (82%) recipients achieved the primary end-point. Nine (53%) recipients achieved insulin independence for a median of 26 months (range 7-39 months) and 6 (35%) remain insulin independent. All recipients were C-peptide positive for at least 3 months. All subjects with unstimulated C-peptide >0.2 nmol/L had cessation of severe hypoglycemia. Nine of the 17 recipients tolerated switching from tacrolimus to sirolimus with similar graft outcomes. There was a small but significant reduction in renal function in the first 12 months. The combination of islet culture, ATG, tacrolimus and MMF is a viable alternative for islet transplantation.

Mobile phone support is associated with reduced ketoacidosis in young adults

AIMS

To determine if access to mobile phone support for sick-day management is associated with reduced hospital admissions with diabetic ketoacidosis in young adults aged 15-25 with Type 1 diabetes.

METHODS

This was an observational study with data collected prospectively from January 2005 to December 2008. A mobile phone support service for sick-day management began in May 2005. Data from clinic attendees (group 1), including age, sex, diabetes duration, referral age, insulin therapy delivery, clinic attendance and HbA(1c) , were compared with clinic attendees with diabetic ketosis accessing sick-day management phone support (group 2), clinic attendees not accessing phone support and admitted with diabetic ketoacidosis (group 3) and non-clinic attendees admitted with diabetic ketoacidosis (group 4).

RESULTS

Age was similar in all groups. Patients in group 3 had significantly shorter duration of diabetes (6.8 ± 3.1 years) than groups 1 or 2 (10.1 and 9.8 years, respectively). Diabetes control was poor in all presentations of diabetic ketoacidosis (groups 2-4, HbA(1c) > 97 mmol/mol, > 11%) and was significantly higher than clinic attendees without ketosis (HbA(1c) 70 mmol/mol, 8.6%; P < 0.001). There was similar attendance at the clinic across all three groups, 2.9 compared with 2.4 compared with 2.1 visits/year, respectively. Thirty-one patients accessed phone support on 83 occasions for sick-day management (mean 2.7 contacts/episode); two patients progressed to admission with diabetic ketoacidosis. Diabetic ketoacidosis admission rates in the clinic population fell significantly from baseline, 0.10 to 0.05 admissions per patient per year (P < 0.05) in the third year.

CONCLUSION

Mobile phone support is associated with reduced progression of ketosis to diabetic ketoacidosis in young adults despite poor diabetes control.

A transition care programme which improves diabetes control and reduces hospital admission rates in young adults with Type 1 diabetes aged 15-25 years

AIMS

To determine if a transition support programme for young adults with diabetes could maintain attendance at a specialist clinic, improve diabetes control and reduce acute hospital admissions with diabetic ketoacidosis (DKA) in 15-25-year-olds with Type 1 diabetes.

METHODS

A transition coordinator/diabetes educator arranged booking and rebooking of appointments for a young adult diabetes clinic based in an adult hospital between July 2001 and March 2006. An after-hours phone support service was initiated. Data collected included source of referral, frequency of clinic attendance and HbA1c at each visit. Numbers of admissions and readmissions with DKA, length of stay and HbA1c on admission were recorded.

RESULTS

One hundred and ninety-one young adults were referred. HbA1c at initial referral was 9.3 +/- 2.17%. HbA1c significantly improved to 8.8 +/- 1.9% (P < 0.001) after a median of five visits with a statistically significant fall in HbA1c of 0.13% per visit (P = 0.01). The greatest improvements were seen in those with starting HbA1c > 11% (-2.5 +/- 2.3%, P < 0.001). Eighty-two percent had attended appointments in the last 6 months. There was a significant reduction in DKA admissions falling by 1/3 (P = 0.05), and in readmissions a significant reduction in length of stay (-3.6 days, P = 0.02), over 3.5 years.

CONCLUSIONS

If young adults are appropriately supported in adult services, clinic attendance is maintained, diabetes control is improved and hospital admission rates with DKA are reduced. The cost savings from reduced admissions covered the costs of the programme.

Insulin secretion and insulin sensitivity are normal in non-diabetic subjects from maternal inheritance diabetes and deafness families

BACKGROUND

The pathophysiological mechanism of diabetes mellitus in the presence of the 3243 A-G tRNALEU(UR) mitochondrial DNA mutation is thought to result from deficient insulin secretion. However, few subjects with normal glucose tolerance have been studied to determine the sequence of events resulting in the development of diabetes mellitus.

AIM

To determine whether abnormalities of insulin sensitivity, insulin secretion or glucose effectiveness are present in non-diabetic subjects with the 3243 A-G tRNALEU(UUR) mitochondrial DNA mutation.

METHODS

Twelve non-diabetic subjects with the mutation were compared with 12 controls, matched for age and anthropometric parameters, using both oral and intravenous glucose tolerance tests, the latter with Minimal Model analysis.

RESULTS

Following an oral glucose load we found significantly higher blood glucose levels at 90 min and 120 min and significantly higher insulin levels at 120 min and 180 min in non-diabetic subjects with the mutation but no difference in the insulinogenic indices at 30 min and 180 min. From the intravenous glucose tolerance test there was no difference in overall glucose tolerance, insulin sensitivity, first- or second-phase insulin secretion, proinsulin secretion or glucose effectiveness. Insulin-independent glucose disposal was increased in subjects with lower insulin sensitivity and declined with increasing age in subjects with the mutation but not in controls.

CONCLUSIONS

While there appear to be subtle defects of glucose handling in non-diabetic subjects with the 3243 mutation, these could not be explained by differences in insulin sensitivity or secretion.

Does mitochondrial genome mutation in subjects with maternally inherited diabetes and deafness decrease severity of diabetic retinopathy?

Two types of retinopathy, diabetic and pigmentary, may be seen in subjects with maternal inheritance diabetes and deafness. The potential for interactions between the two retinopathies has not been explored. The mitochondrial mutation may affect development of diabetic retinopathy in subjects with MIDD by altering normal pathways of glucose metabolism. We identified five unrelated MIDD kindreds with 61 living maternal line family members. Twenty-three of the family members, 12 with diabetes mellitus and 11 without volunteered to be studied. Subjects were graded for severity of diabetic retinopathy and presence or absence of pigmentary retinopathy after slit lamp biomicroscopy, retinal photography of seven standard fields and fluorescein angiography. Blood was taken, in the fasted state, from MIDD subjects (duration of diabetes 17.0+/-6.9 yr) and non-diabetic subjects with the mutation, for assay of sorbitol and glucose and values compared with diabetic and non-diabetic control subjects without the mutation. Diabetic retinopathy was absent in 9/12 subjects (75%), with 3 having mild non-proliferative retinopathy. No one had cataract. Red blood cell sorbitol levels, adjusted for ambient blood glucose, were significantly lower in MIDD subjects compared with diabetic subjects (1.16+/-0.5 cf. 2.03+/-1.1, x 10(-3) g mmol(-1), p=0.04). Pigmentary retinopathy was present in 15 of 23 subjects, of whom 13 had some abnormality of glucose tolerance. Abnormal glucose tolerance was strongly associated with the development of pigmentary retinopathy (odds ratio 19.5, p=0.008). In conclusion, there appears to be a decreased prevalence of diabetic retinopathy and cataract in MIDD, which we propose is due to reduced glucose metabolism by the polyol pathway. Abnormal glucose tolerance increases the clinical expression of pigmentary retinopathy in subjects with a mitochondrial genome mutation. A greater understanding of the metabolic effects of mitochondrial DNA mutations has the potential to give insight into the mechanisms of diabetic retinopathy and other complications of diabetes mellitus.

Menstrual disturbance and hypersecretion of progesterone in women with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

OBJECTIVE

While menstrual disturbance is often quoted as a feature of congenital adrenal hyperplasia (CAH), little is known about the mechanism of this symptom. We set out to determine the relationship between menstrual pattern and biochemical characteristics of women with CAH due to 21-hydroxylase deficiency.

PATIENTS AND DESIGN

All 21 female patients with classic CAH attending the adult endocrinology clinics at The Middlesex Hospital were reviewed. Their ages at menarche and menstrual pattern were recorded and blood samples were taken in the follicular phase of the menstrual cycle when on their usual maintenance therapy.

MEASUREMENTS

Measurements of serum LH, FSH, progesterone, 17 alpha-hydroxyprogesterone, testosterone, androstenedione and plasma renin activity were recorded. Urinary steroid profiles were obtained by gas chromatography and mass spectrometry. Molecular genetic analysis of the 21-hydroxylase gene was performed on leucocyte DNA.

RESULTS

In the 18 patients who had spontaneous menarche the degree of menstrual disturbance and progesterone excess was related to the effectiveness of adrenal suppressive therapy. Three out of 21 patients, however, failed to experience menarche on standard medical therapy. These patients with primary amenorrhoea were characterized by reduced endometrial thickening, by non-suppressible serum progesterone concentrations despite suppression of 17 alpha-hydroxyprogesterone levels and by the presence of progesterone metabolites in urinary steroid profiles. Molecular genetic analysis did not differentiate between patients with raised progesterone concentrations and those without.

CONCLUSION

A subgroup of women with congenital adrenal hyperplasia have the triad of non-suppressible serum progesterone of adrenal origin, primary amenorrhoea and infertility due to failure of endometrial thickening. The characteristic urinary steroid profile best distinguishes this subgroup of women from others with congenital adrenal hyperplasia and menstrual disturbance due to inadequate adrenal suppression.