The effect of insulin analogs in people with type 1 diabetes at increased risk of severe hypoglycemia.

Type 1 diabetes is characterized by insulin deficiency, and treatment is to supply insulin mimicking the physiological endogenous insulin secretion. Since its discovery, insulin therapy has evolved, and since the 1990s, an increasing number of insulin analogs with various pharmacokinetic and pharmacodynamic profiles have become available. Despite the improvement of insulin therapy, hypoglycemia remains the main side effect and is a daily concern for many people with diabetes and their families. A proportion of people with type 1 diabetes are at increased risk of hypoglycemia and experience recurring episodes. When designing insulin trials, this group of people is most often excluded in order to reduce the risk of adverse study outcomes, even though it may be the group that may benefit the most from treatment with new insulins. The results of the phase III trials, therefore, underestimate the clinical impact and pharmacoeconomic effect of the implementation of new insulins in the broader type 1 diabetes population. This paper reviews the four insulin trials that include people at increased risk of hypoglycemia. In general, the studies confirm the results from phase III trials in terms of similar reduction and maintenance of HbA1c, as well as relative rate reductions of hypoglycemia. However, the absolute treatment differences in the reduction of hypoglycemia are even greater in the trials, including people at high risk of hypoglycemia. This emphasizes the importance of including people at high risk of hypoglycemia to assess the full clinical and pharmacoeconomic benefit of new insulins.

The Effect of Insulin Degludec Versus Insulin Glargine U100 on Glucose Metrics Recorded During Continuous Glucose Monitoring in People With Type 1 Diabetes and Recurrent Nocturnal Severe Hypoglycemia.

AIM: Comparing continuous glucose monitoring (CGM)-recorded metrics during treatment with insulin degludec (IDeg) versus insulin glargine U100 (IGlar-100) in people with type 1 diabetes (T1D) and recurrent nocturnal severe hypoglycemia. MATERIALS AND METHODS: This is a multicenter, two-year, randomized, crossover trial, including 149 adults with T1D and minimum one episode of nocturnal severe hypoglycemia within the last two years. Participants were randomized 1:1 to treatment with IDeg or IGlar-100 and given the option of six days of blinded CGM twice during each treatment. CGM traces were reviewed for the percentage of time-within-target glucose range (TIR), time-below-range (TBR), time-above-range (TAR), and coefficient of variation (CV). RESULTS: Seventy-four participants were included in the analysis. Differences between treatments were greatest during the night (23:00-06:59). Treatment with IGlar-100 resulted in 54.0% vs 49.0% with IDeg TIR (70-180 mg/dL) (estimated treatment difference [ETD]: -4.6%, 95% confidence interval [CI]: -9.1, -0.0, P = .049). TBR was lower with IDeg at level 1 (54-69 mg/dL) (ETD: -1.7% [95% CI: -2.9, -0.5], P < .05) and level 2 (<54 mg/dL) (ETD: -1.3% [95% CI: -2.1, -0.5], P = .001). TAR was higher with IDeg compared with IGlar-100 at level 1 (181-250 mg/dL) (ETD: 4.0% [95% CI: 0.8, 7.3], P < .05) and level 2 (> 250 mg/dL) (ETD: 4.0% [95% CI: 0.8, 7.2], P < .05). The mean CV was lower with IDeg than that with IGlar-100 (ETD: -3.4% [95% CI: -5.6, -1.2], P < .05). CONCLUSION: For people with T1D suffering from recurrent nocturnal severe hypoglycemia, treatment with IDeg, compared with IGlar-100, results in a lower TBR and CV during the night at the expense of more TAR.

Impact of Polymorphism in the ß2-Receptor Gene on the Metabolic Response to Epinephrine After Repeated Hypoglycemia.

The ß2-receptor mediates the metabolic response to epinephrine. This study investigates the impact of the ß2-receptor gene (ADRB2) polymorphism Gly16Arg on the metabolic response to epinephrine before and after repetitive hypoglycemia. Twenty-five healthy men selected according to ADRB2 genotype being homozygous for either Gly16 (GG) (n = 12) or Arg16 (AA) (n = 13) participated in 4 trial days (D1-4): D1pre and D4post with epinephrine 0.06 µg kg-1 ⋅ min-1 infusion and D2hypo1-2 and D3hypo3 with three periods of hypoglycemia by an insulin-glucose clamp. At D1pre, the insulin (mean ± SEM of area under the curve 44 ± 8 vs. 93 ± 13 pmol ⋅ L-1 h; P = 0.0051), glycerol (79 ± 12 vs. 115 ± 14 µmol ⋅ L-1 h; P = 0.041), and free fatty acid (724 ± 96 vs. 1,113 ± 140 µmol ⋅ L-1 h; P = 0.033) responses to epinephrine were decreased in AA participants compared with GG participants but without a difference in glucose response. There were no differences in response to epinephrine between genotype groups after repetitive hypoglycemia at D4post. The metabolic substrate response to epinephrine was decreased in AA participants compared with GG participants but without a difference between genotype groups after repetitive hypoglycemia. ARTICLE HIGHLIGHTS: This study investigates the impact of the ß2-receptor gene (ADRB2) polymorphism Gly16Arg on the metabolic response to epinephrine before and after repetitive hypoglycemia. Healthy men homozygous for either Gly16 (n = 12) or Arg16 (n = 13) participated in the study. Healthy people with the Gly16 genotype have increased metabolic response to epinephrine compared with the Arg16 genotype but without a difference between genotypes after repetitive hypoglycemia.

Effect of insulin degludec versus insulin glargine U100 on nocturnal glycaemia assessed by plasma glucose profiles in people with type 1 diabetes prone to nocturnal severe hypoglycaemia.

AIM: To compare nocturnal glucose profiles according to hourly plasma glucose measurements during treatment with insulin degludec and insulin glargine U100 in a cohort of people with type 1 diabetes prone to nocturnal severe hypoglycaemia. MATERIALS AND METHODS: The HypoDeg trial is a 2-year investigator-initiated, randomized, controlled crossover trial in 149 participants randomized to treatment with insulin degludec and insulin glargine U100 for 12 months each. The 51 participants in this predefined substudy stayed at least one night in hospital during each treatment arm for plasma glucose samples to be taken. Endpoints were glucose profiles, including mean plasma glucose, glycaemic variability and risk of hypoglycaemia. RESULTS: There were no differences between treatments regarding mean plasma glucose. We saw a flatter glucose profile during insulin degludec compared with insulin glargine U100 treatment, which had a nadir at 4:00 AM, with a subsequent rise. During treatment with insulin degludec, the participants had lower glycaemic variability, with an estimated treatment difference of -4.3% (95% confidence interval [CI] -8.1 to -0.5; P < 0.05). Participants treated with insulin degludec were less likely to experience nocturnal hypoglycaemia below 3.0 mmol/L (hazard ratio 0.36 [95% CI 0.17-0.73; P < 0.05]). CONCLUSION: Based on nocturnal plasma glucose measurements, treatment with insulin degludec compared with insulin glargine U100 administered in the evening results in lower glycaemic variability and lower risk of nocturnal hypoglycaemia without differences in mean plasma glucose.

The updated Pedersen-Bjergaard method for assessment of awareness of hypoglycaemia in type 1 diabetes.

INTRODUCTION: Loss of awareness of hypoglycaemia is the major risk factor for severe hypoglycaemia in type 1 diabetes. Three methods for assessment of self-reported awareness have been validated and used more widely: the Gold, the Clarke and the Pedersen-Bjergaard classification. Comparisons between the methods are hampered by the latter operating with three classes, whereas the other methods are bimodal. We have therefore updated the Pedersen-Bjergaard classification and here present a comparison of the three methods. METHODS: Adult people with type 1 diabetes (n = 325) completed a validated questionnaire. Hypoglycaemia awareness was self-reported by the three methods: Gold, Clarke and Pedersen-Bjergaard scores. The latter was updated by renaming the previous "impaired" class to "intermediate". RESULTS: A total of 24%, 17% and 14% of patients were classified as having loss of awareness by the Gold, Clarke and updated Pedersen-Bjergaard methods, respectively, with reasonably good agreement and all with increased rates of severe hypoglycaemia. The latter classified 43% with normal and 43% with intermediate awareness and low and average rate of severe hypoglycaemia, respectively. CONCLUSION: The three classifications identified people with loss of awareness with a reasonably high degree of concordance. In contrast to the others, the updated Pedersen-Bjergaard method identified groups with normal and intermediate awareness with clinically significant different risks of severe hypoglycaemia. FUNDING: The Research Foundation of Nordsjællands Hospital and the Beckett Foundation. TRIAL REGISTRATION: not relevant.

Impact of Polymorphism in the ß2-Receptor Gene on Metabolic Responses to Repeated Hypoglycemia in Healthy Humans.

CONTEXT: The Arg16 variant in the ß2-receptor gene is associated with increased risk of severe hypoglycemia in subjects with type 1 diabetes mellitus. OBJECTIVE: We hypothesized that the Arg16 variant is associated with decreased metabolic and symptomatic responses to recurrent hypoglycemia. METHODS: Twenty-five healthy male subjects selected according to ADRB2 genotype and being homozygous for either Arg16 (AA; n = 13) or Gly16 (GG; n = 12) participated in 2 consecutive trial days with 3 periods of hypoglycemia (H1-H3) induced by a hyperinsulinemic hypoglycemic clamp. The main outcome measure was mean glucose infusion rate (GIR) during H1-H3. RESULTS: During H1-H3, there was no difference between AA or GG subjects in GIR, counter-regulatory hormones (glucagon, epinephrine, cortisol, growth hormone), or substrate levels of lactate, glycerol, and free fatty acids (FFAs), and no differences in symptom response score or cognitive performance (trail making test, Stroop test). At H3, lactate response was reduced in both genotype groups, but AA subjects had decreased response (mean ±â€…standard error of the mean of area under the curve) of glycerol (-13.1 ±â€…3.8 µmol L-1 hours; P = .0052), FFA (-30.2 ±â€…11.1 µmol L-1 hours; P = .021), and ß-hydroxybutyrate (-0.008 ±â€…0.003 mmol L-1 hour; P = .027), while in GG subjects alanine response was increased (negative response values) (-53.9 ±â€…20.6 µmol L-1 hour; P = .024). CONCLUSION: There was no difference in GIR between genotype groups, but secondary outcomes suggest a downregulation of the lipolytic and ß-hydroxybutyrate responses to recurrent hypoglycemia in AA subjects, in contrast to the responses in GG subjects.

Continuous Glucose Monitoring-Recorded Hypoglycemia with Insulin Degludec or Insulin Glargine U100 in People with Type 1 Diabetes Prone to Nocturnal Severe Hypoglycemia.

Background and Aims: Nocturnal hypoglycemia is mainly a consequence of inappropriate basal insulin therapy in type 1 diabetes (T1D) and may compromise optimal glycemic control. Insulin degludec is associated with a lower risk of nocturnal hypoglycemia in T1D. As nocturnal hypoglycemia is often asymptomatic, we applied continuous glucose monitoring (CGM) to detect a more precise occurrence of nocturnal hypoglycemia in the HypoDeg trial, comparing insulin degludec with insulin glargine U100 in people with T1D and previous nocturnal severe hypoglycemia. Materials and Methods: In the HypoDeg trial, 149 people with T1D were included in an open-label randomized cross-over trial. Sixty-seven participants accepted optional participation in the predefined substudy of 4 × 6 days of blinded CGM requiring completion of at least one CGM period in each treatment arm. CGM data were reviewed for hypoglycemic events. Results: Treatment with insulin degludec resulted in a relative rate reduction (RRR) of 36% (95% confidence interval [CI]: 10%-54%; P < 0.05) in nocturnal CGM-recorded hypoglycemia (≤3.9 mmol/L), corresponding to an absolute rate reduction (ARR) of 0.85 events per person-week. In nocturnal CGM-recorded hypoglycemia (≤3.0 mmol/L), we found an RRR of 53% (95% CI: 36%-65%; P < 0.001), corresponding to an ARR of 0.75 events per person-week. At the lower detection limit of the CGM (≤2.2 mmol/L), treatment with insulin degludec resulted in a significant RRR of 58% (95% CI: 23%-77%; P = 0.005). The reductions were primarily due to significant RRRs in asymptomatic hypoglycemia. Conclusion: In people with T1D, prone to nocturnal severe hypoglycemia, insulin degludec compared with insulin glargine U100 significantly reduces nocturnal CGM-recorded hypoglycemia. www.clinicaltrials.gov (#NCT02192450).

Continuous Glucose Monitoring (CGM) Readings During Patient-Reported Symptomatic Hypoglycemia: Assessment of the Advanced Technologies and Treatments for Diabetes Consensus Definition of CGM-Recorded Hypoglycemia.

Aim: Continuous glucose monitoring (CGM) is widely used in clinical practice and research to detect hypoglycemia. A consensus definition of CGM-recorded hypoglycemia is made by a group of international experts under the auspice of the Advanced Technologies and Treatments for Diabetes (ATTD). The purpose of this study is to compare the definition with patient-reported hypoglycemia. Methods: In a prospective, observational study of 186 patients with type 1 diabetes using blinded Medtronic iPro 2 CGM for 6 days, every patient-reported symptomatic hypoglycemic event and interstitial glucose (IG) values at the registration time were classified according to the ATTD definition of CGM-recorded hypoglycemia. For comparison between CGM and self-monitored blood glucose (SMBG) values, the International Hypoglycemia Study Group (IHSG) classification of hypoglycemia and chi-square test were used. Results: A total of 321 events of symptomatic hypoglycemia were reported by 68% of the patients, corresponding to 2.0 ± 2.3 events (mean ± standard deviation) per patient-week. A total of 206 (64%) events met the CGM consensus definition. In the remaining 115 (36%) not-confirmed events, 5 events had an IG <3.9 mmol/L, which lasted <15 min. The overall mean IG value was 3.6 ± 1.1 mmol/L (median 3.1, range 2.2-10.4). In symptomatic hypoglycemic events with both CGM and SMBG data, SMBG confirmed significantly more symptomatic hypoglycemic events than CGM (P < 0.001). Conclusion: CGM-recorded hypoglycemia according to the consensus definition is present at two thirds of all patient-reported events when recorded by the Medtronic iPro 2 system. The recommended minimum duration of a hypoglycemic event of 15 min is supported by the study. SMBG measurements detect significantly more symptomatic hypoglycemic events than Medtronic iPro 2 CGM.

Comparison of treatment with insulin degludec and glargine U100 in patients with type 1 diabetes prone to nocturnal severe hypoglycaemia: The HypoDeg randomized, controlled, open-label, crossover trial.

AIM: To investigate whether the long-acting insulin analogue insulin degludec compared with insulin glargine U100 reduces the risk of nocturnal symptomatic hypoglycaemia in patients with type 1 diabetes (T1D). METHODS: Adults with T1D and at least one episode of nocturnal severe hypoglycaemia during the last 2 years were included in a 2-year prospective, randomized, open, multicentre, crossover trial. A total of 149 patients were randomized 1:1 to basal-bolus therapy with insulin degludec and insulin aspart or insulin glargine U100 and insulin aspart. Each treatment period lasted 1 year and consisted of 3 months of run-in or crossover followed by 9 months of maintenance. The primary endpoint was the number of blindly adjudicated nocturnal symptomatic hypoglycaemic episodes. Secondary endpoints included the occurrence of severe hypoglycaemia. We analysed all endpoints by intention-to-treat. RESULTS: Treatment with insulin degludec resulted in a 28% (95% CI: 9%-43%; P = .02) relative rate reduction (RRR) of nocturnal symptomatic hypoglycaemia at level 1 (≤3.9 mmol/L), a 37% (95% CI: 16%-53%; P = .002) RRR at level 2 (≤3.0 mmol/L), and a 35% (95% CI: 1%-58%; P = .04) RRR in all-day severe hypoglycaemia compared with insulin glargine U100. CONCLUSIONS: Patients with T1D prone to nocturnal severe hypoglycaemia have lower rates of nocturnal symptomatic hypoglycaemia and all-day severe hypoglycaemia with insulin degludec compared with insulin glargine U100.

Effects of 18-months metformin versus placebo in combination with three insulin regimens on RNA and DNA oxidation in individuals with type 2 diabetes: A post-hoc analysis of a randomized clinical trial.

Formation of reactive oxygen species has been linked to the development of diabetes complications. Treatment with metformin has been associated with a lower risk of developing diabetes complications, including when used in combination with insulin. Metformin inhibits Complex 1 in isolated mitochondria and thereby decreases the formation of reactive oxygen species. Thus, we post-hoc investigated the effect of metformin in combination with different insulin regimens on RNA and DNA oxidation in individuals with type 2 diabetes. Four hundred and fifteen individuals with type 2 diabetes were randomized (1:1) to blinded treatment with metformin (1,000 mg twice daily) versus placebo and to (1:1:1) open-label biphasic insulin, basal-bolus insulin, or basal insulin therapy in a 2 × 3 factorial design. RNA and DNA oxidation were determined at baseline and after 18 months measured as urinary excretions of 8-oxo-7,8-dihydroguanosine (8-oxoGuo) and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), respectively. Urinary excretion of 8-oxoGuo changed by +7.1% (95% CI: 0.5% to 14.0%, P = 0.03) following metformin versus placebo, whereas changes in 8-oxodG were comparable between intervention groups. Biphasic insulin decreased urinary excretion of 8-oxoGuo (within-group: -9.6% (95% CI: -14.4% to -4.4%)) more than basal-bolus insulin (within-group: 5.2% (95% CI: -0.5% to 11.2%)), P = 0.0002 between groups, and basal insulin (within-group: 3.7% (95% CI: -2.0% to 9.7%)), P = 0.0007 between groups. Urinary excretion of 8-oxodG decreased more in the biphasic insulin group (within-group: -9.9% (95% CI: -14.4% to -5.2%)) than basal-bolus insulin (within group effect: -1.2% (95% CI: -6.1% to 3.9%)), P = 0.01 between groups, whereas no difference was observed compared with basal insulin. In conclusion, eighteen months of metformin treatment in addition to different insulin regimens increased RNA oxidation, but not DNA oxidation. Biphasic insulin decreased both RNA and DNA oxidation compared with other insulin regimens.

Gustatory sweating in people with type 1 and type 2 diabetes mellitus: Prevalence and risk factors.

OBJECTIVE: Gustatory sweating (GS) is characterized by profuse sweating during or immediately after ingestion of food and is known as a complication of diabetes mellitus (DM). This study aimed to determine the prevalence of GS and to characterize the sweating in a cohort of patients with type 1 and type 2 diabetes mellitus (T1DM and T2DM) as compared with a control group. METHODS: In a cross-sectional study, 665 outpatients with T1DM and 505 outpatients with T2DM filled in an 8-point questionnaire about GS. Answers were paired with medical data from the electronic patient records to explore associations with DM complications. The control group consisted of 1158 persons without DM answering the same questionnaire in an online version. RESULTS: In people with T1DM and T2DM, the prevalence of GS was 10% (95% CI 7%-12%) and 13% (95% CI 10%-16%), respectively. In the control group, the prevalence of GS was 5% (95% CI 3%-6%). Most commonly, people sweat on the face and/or head and upper body with a duration of 10-30 min albeit in the control group <10 min. In patients with T1DM, increased HbA1c was associated with GS (OR 1.3 [95% CI 1.05-1.6], p = .016), and in T2DM, younger age (OR 0.95 [95% CI 0.92-0.99), p = .006), presence of severe peripheral neuropathy (OR 2.33 [95% CI 1.04-5.2], p = .039) and absence of proliferative retinopathy were associated with GS (OR 0.22 [95% CI 0.07-0.71], p = .011). CONCLUSION: We found the prevalence of gustatory sweating of 11% in a hospital-based cohort of patients with T1DM and T2DM. This was twice as high as in non-diabetic control persons. Associations between GS and known diabetes complications could only be demonstrated in T2DM. Compared with a control group without DM, odds for GS are higher in people with DM and age >45.

Synthetic long-acting insulin analogs for the management of type 1 diabetes: an update.

INTRODUCTION: Type 1 diabetes is characterized by insulin deficiency and requires near-physiological insulin replacement. In most patients, this is accomplished by basal bolus therapy consisting of a long-acting basal insulin administered once or twice daily and short-acting insulin with main meals. Several long-acting insulin analogs have been developed to optimize basal insulin therapy. AREAS COVERED: This paper reviews the design of - and data from - randomized controlled trials (RCTs) to assess glucose lowering efficacy and safety of long-acting insulin analogs for the treatment of type 1 diabetes. EXPERT OPINION: Due to the non-inferiority treat-to-target design of insulin, RCTs treatment differences primarily appear as differences in hypoglycemia risk. Data suggest that the first generation long-acting insulin analogs insulin glargine U100 and insulin detemir have a similar glucose lowering efficacy compared to NPH insulin but a lower risk of hypoglycemia, particularly during nighttime. The newer analogs insulin glargine U300 and insulin degludec provide non-inferior efficacy, although insulin glargine U300 is less potent unit-to-unit. Insulin degludec reduces hypoglycemia risk compared to insulin glargine U100. Future studies should explore the potential for further improvement of treatment results in type 1 diabetes by a structured approach to personalization of basal insulin therapy.

Effect of 12-week continuous positive airway pressure therapy on glucose levels assessed by continuous glucose monitoring in people with type 2 diabetes and obstructive sleep apnoea; a randomized controlled trial.

Aim: Obstructive sleep apnoea (OSA) is frequent in type 2 diabetes (T2D). The aim was to investigate the effect of a 12-week treatment with continuous positive airway pressure (CPAP) on glycaemic control assessed by continuous glucose monitoring (CGM), HbA1c and fasting blood glucose in patients with T2D and newly detected OSA. Methods: In a randomized controlled multicentre study, 72 participants with T2D and moderate to severe OSA (78% male, age 62 ± 7, AHI 35 ± 15) were recruited from outpatient clinics in three Danish hospitals and were randomized to CPAP intervention or control. The main outcome was glycaemic control assessed by 6 days CGM at baseline and after 12-week therapy, as well as by HbA1c and fasting blood glucose. Results: No significant changes were found in average glucose levels, time in glucose range, time with hypoglycaemia, time with hyperglycaemia or coefficient of variability. HbA1c decreased 0.7 mmol/mol (0.07%; P = .8) in the CPAP group and increased 0.8 mmol/mol (0.08%; P = .6) in the control group (intergroup difference, P = .6). Fasting blood glucose increased by 0.2 mmol/L (P = .02) in the CPAP group and by 0.4 mmol/L (P = .01) in the control group (intergroup difference, P = .7). In a prespecified subgroup analysis comparing participants with high adherence (minimum usage of four hours/night for 70% of all nights) to CPAP to the control group, no significant changes were observed either, although these participants had a tendency towards better glycaemic indices. Conclusions: CPAP treatment for 12 weeks does not significantly change glycaemic control in patients with type 2 diabetes and OSA.

Effects of continuous glucose monitor-recorded nocturnal hypoglycaemia on quality of life and mood during daily life in type 1 diabetes.

AIMS/HYPOTHESIS: The aim of this work was to assess the effect of spontaneous nocturnal hypoglycaemia on quality of life and mood during subsequent days in type 1 diabetes. METHODS: A total of 153 people with type 1 diabetes participated in 6 days of blinded continuous glucose monitoring while documenting hypoglycaemic symptoms, quality of life and mood, daily. Hypoglycaemia was defined by interstitial glucose ≤3.9 mmol/l (IG3.9) and ≤ 3.0 mmol/l (IG3.0) for ≥15 min and was classified as asymptomatic if no hypoglycaemic symptoms were reported. RESULTS: Self-estimated quality of life assessed by the EQ-5D VAS (but not by the WHO Well-Being Index) was higher the day after asymptomatic (but not after symptomatic) hypoglycaemic nights, as compared with non-hypoglycaemic nights (IG3.9, p = 0.021; IG3.0, p = 0.048). The effect increased with lower glucose nadir and longer duration of nocturnal hypoglycaemia (IG3.9, p = 0.03). The finding was confined to participants with impaired hypoglycaemia awareness. There was no effect of nocturnal hypoglycaemia on mood or self-estimated effectiveness at work the following day. CONCLUSIONS/INTERPRETATION: Individuals with type 1 diabetes and impaired hypoglycaemia awareness reported higher quality of life on days preceded by nights with asymptomatic (but not symptomatic) hypoglycaemia. The effect was amplified by lower glucose nadir and longer duration of the episodes and may help explain resistance to implementation of interventions to reduce hypoglycaemia in many people with impaired hypoglycaemia awareness.

Metformin may adversely affect orthostatic blood pressure recovery in patients with type 2 diabetes: substudy from the placebo-controlled Copenhagen Insulin and Metformin Therapy (CIMT) trial.

BACKGROUND: Metformin has been shown to have both neuroprotective and neurodegenerative effects. The aim of this study was to investigate the effect of metformin in combination with insulin on cardiovascular autonomic neuropathy (CAN) and distal peripheral neuropathy (DPN) in individuals with type 2 diabetes (T2DM). METHODS: The study is a sub-study of the CIMT trial, a randomized placebo-controlled trial with a 2 × 3 factorial design, where 412 patients with T2DM were randomized to 18 months of metformin or placebo in addition to open-labelled insulin. Outcomes were measures of CAN: Changes in heart rate response to deep breathing (beat-to-beat), orthostatic blood pressure (OBP) and heart rate and vibration detection threshold (VDT) as a marker DPN. Serum levels of vitamin B12 and methyl malonic acid (MMA) were analysed. RESULTS: After 18 months early drop in OBP (30 s after standing) was increased in the metformin group compared to placebo: systolic blood pressure drop increased by 3.4 mmHg (95% CI 0.6; 6.2, p = 0.02) and diastolic blood pressure drop increased by 1.3 mmHg (95% CI 0.3; 2.6, p = 0.045) compared to placebo. Beat-to-beat variation decreased in the metformin group by 1.1 beats per minute (95% CI - 2.4; 0.2, p = 0.10). Metformin treatment did not affect VDT group difference - 0.33 V (95% CI - 1.99; 1.33, p = 0.39) or other outcomes. Changes in B12, MMA and HbA1c did not confound the associations. CONCLUSIONS: Eighteen months of metformin treatment in combination with insulin compared with insulin alone increased early drop in OBP indicating an adverse effect of metformin on CAN independent of vitamin B12, MMA HbA1c. Trial registration The protocol was approved by the Regional Committee on Biomedical Research Ethics (H-D-2007-112), the Danish Medicines Agency and registered with ClinicalTrials.gov (NCT00657943).

Prediction of carotid intima-media thickness and its relation to cardiovascular events in persons with type 2 diabetes.

AIMS: To investigate measures of carotid intima-media thickness (IMT) and conventional cardiovascular (CV) risk factors as predictors of future carotid IMT, and the prediction of CV events during follow-up based on measures of carotid IMT. METHODS: Observational longitudinal study including 230 persons with type 2 diabetes (T2D). RESULTS: Mean age at follow-up was 66.7 (SD 8.5) years, 30.5% were women and mean body mass index (BMI) was 31.8 (4.4) kg/m2. Carotid IMT was measured at baseline, after 18 months of intervention in the Copenhagen Insulin and Metformin Therapy (CIMT) trial and after a mean follow-up of 6.4 (1.0) years. Baseline carotid IMT, carotid IMT after 18 months' intervention, and CV risk factors (age, sex and baseline systolic blood pressure) gave the best prediction of carotid IMT (root mean-squared error of prediction of 0.106 and 95% prediction error probability interval of -0.160, 0.204). CONCLUSIONS: Measures of carotid IMT combined with CV risk factors at baseline predicts attained carotid IMT better than measures of carotid IMT or CV risk factors alone. Carotid IMT did not predict CV events, and the present results do not support the use of carotid IMT as a predictor of CV events in persons with T2D.

Progression in risk factors during 36 years of follow-up and prediction of carotid intima-media thickness in a large cohort of adults with and without diabetes.

Carotid intima-media thickness (IMT) can assess the cumulative effect of atherosclerotic risk factors and provides an independent predictor of future cardiovascular (CV) risk. The aim of this study was to investigate the progression of conventional risk factors in 933 long-term survivors from a Danish cohort with and without diabetes mellitus (DM) as predictors for attained carotid IMT during 35.6 (0.7) years of follow-up. Persons who participated in the first, the last and one of the intermediate rounds of the Copenhagen City Heart Study, and who had had an ultrasound-derived measure of the carotid IMT performed at the last examination were included in the analyses. The risk factors varied between persons with and without DM during the 36 years, but the difference in blood pressure disappeared in the fifth examination, where, in addition, total cholesterol was found to be lower in persons with DM. In this cohort there were no difference in attained carotid IMT between persons with and without DM at the last examination. The following risk factors were found to best predict carotid IMT: age, maximum systolic BP, average systolic BP, average BMI, minimum BMI, sex and years of smoking. The prediction of carotid IMT was clinically poor with a root mean-squared error of prediction (RMSEP) of 0.134 mm and a 95% prediction error probability interval of (-0.22; 0.30). Furthermore, the distribution of prediction errors was skewed to the right indicating that the prediction errors were larger among persons with high carotid IMT.

Effect of Metformin vs. Placebo in Combination with Insulin Analogues on Bone Markers P1NP and CTX in Patients with Type 2 Diabetes Mellitus.

Preclinical studies have shown a potential osteoanabolic effect of metformin but human studies of how metformin affects bone turnover are few. A post hoc sub-study analysis of an 18-month multicenter, placebo-controlled, double-blinded trial in type 2 diabetes mellitus (T2DM), randomizing participants to metformin versus placebo both in combination with different insulin analogue regimens (Metformin + Insulin vs. Placebo + Insulin). Patients were not treatment naive at baseline, 83% had received metformin, 69% had received insulin, 57.5% had received the combination of metformin and insulin before entering the study. Bone formation and resorption were assessed by measuring, N-terminal propeptide of type I procollagen (P1NP) and C-terminal telopeptide of type I collagen (CTX) at baseline and end of study. The influence of gender, age, smoking, body mass index (BMI), T2DM duration, glycosylated hemoglobin A1c (HbA1c), c-reactive protein (CRP) and insulin dosage was also included in the analyses. The levels of bone formation marker P1NP and bone resorption marker CTX increased significantly in both groups during the trial. P1NP increased less in the Metformin + Insulin compared to the placebo + insulin group (p = 0.001) (between group difference change), while the increases in CTX levels (p = 0.11) were not different. CRP was inversely associated (p = 0.012) and insulin dosage (p = 0.011) was positively related with change in P1NP levels. BMI (p = 0.002) and HbA1C (p = 0.037) were inversely associated with change in CTX levels. During 18 months of treatment with metformin or placebo, both in combination with insulin, bone turnover increased in both groups. But the pattern was different as the bone formation marker (P1NP) increased less during Metformin + Insulin treatment, while change in bone resorption (CTX) was not significantly different between the two groups.

Effect of 12 weeks continuous positive airway pressure on day and night arterial stiffness and blood pressure in patients with type 2 diabetes and obstructive sleep apnea: A randomized controlled trial.

The objective of this study was to evaluate the effect of continuous positive airway pressure treatment on pulse wave velocity and blood pressure in patients with type 2 diabetes and obstructive sleep apnea. A randomized controlled study was performed, including 72 patients with type 2 diabetes and newly diagnosed obstructive sleep apnea recruited from outpatient clinics at three Danish hospitals. The patients were randomized to continuous positive airway pressure for 12 weeks or no continuous positive airway pressure. Office measurements were performed at baseline, 4 weeks and 12 weeks. At baseline and 12 weeks, a 24-hr measurement of pulse wave velocity and blood pressure was performed. No significant change was observed in the primary outcome variable of carotid-femoral pulse wave velocity measured with SphygmoCor. With the Mobil-O-Graph, changes in office pulse wave velocity between the groups were significant: 0.3 m/s; 95% confidence interval, 0.1-0.6; p = .02. The group receiving continuous positive airway pressure had a larger decrease in pulse wave velocity than controls but none of the changes within the groups were significant. No significant change in ambulatory blood pressure was observed in any of the two groups after 12 weeks. In conclusion, continuous positive airway pressure treatment for 12 weeks does not significantly reduce pulse wave velocity or blood pressure in patients with type 2 diabetes and obstructive sleep apnea.