Efficacy and safety of liraglutide in type 1 diabetes by baseline characteristics in the ADJUNCT ONE and ADJUNCT TWO randomized controlled trials

AIM

To evaluate 26 weeks of liraglutide treatment in type 1 diabetes (T1D) by subgroups in the ADJUNCT ONE and ADJUNCT TWO trials.

MATERIALS AND METHODS

ADJUNCT ONE and ADJUNCT TWO were randomized controlled phase 3 trials in 1398 and 835 participants with T1D treated with liraglutide (1.8, 1.2, or 0.6 mg) or placebo (adjuncts to insulin). This post hoc analysis evaluated treatment effects by subgroups: HbA1c (< or ≥8.5%), body mass index (BMI; < or ≥27 kg/m² ), and insulin regimen (basal bolus or continuous subcutaneous insulin infusion).

RESULTS

In both trials at week 26, reductions in HbA1c, body weight, and daily insulin dose did not differ significantly (P > .05) by baseline HbA1c or BMI. Risk of clinically significant hypoglycaemia or hyperglycaemia with ketosis did not differ significantly (P > .05) by baseline HbA1c, BMI, or insulin regimen. At week 26 in ADJUNCT ONE, these risks did not differ (P > .05) between treatment groups. Placebo-adjusted reductions in HbA1c, body weight, and insulin dose (-0.30%-points, -5.0 kg, and -12%, respectively, with liraglutide 1.8 mg), were significant (P < .05), greater than at week 52, and similar to those in ADJUNCT TWO (-0.35%, -4.8 kg, and -10%, respectively, with liraglutide 1.8 mg).

CONCLUSIONS

In ADJUNCT ONE and ADJUNCT TWO, the efficacy and glycaemic safety of liraglutide did not depend on subgroups, leaving residual beta-cell function as the only identified variable impacting the effect of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in T1D. These findings support a role for GLP-1 RAs as adjuncts to insulin in T1D, warranting further study.

Liraglutide reduces cardiac adipose tissue in type 2 diabetes: A secondary analysis of the LIRAFLAME randomized placebo-controlled trial

AIM

To test the hypothesis that treatment with liraglutide can reduce cardiac adipose tissue.

MATERIALS AND METHODS

LIRAFLAME is a randomized placebo-controlled, double-blind, parallel clinical study. Participants with type 2 diabetes were randomized to treatment with liraglutide 1.8 mg/d or placebo for 26 weeks. Computed tomography was performed at baseline and at end of treatment to evaluate the cardiac adipose tissue volume, quantified automatically. We report the results of a secondary endpoint evaluating changes in cardiac adipose tissue.

RESULTS

A total of 102 participants were randomly assigned to liraglutide (n = 51) or placebo (n = 51). At baseline, the mean (SD) cardiac adipose tissue volume was comparable between the liraglutide and the placebo group (232.6 [112.8] vs. 227.0 [103.2] mL; P = 0.80). The mean change in body weight was -3.7 (-4.8, -2.6) kg in the liraglutide and -0.18 (-0.76, 0.40) kg in the placebo group. From baseline to end of treatment the mean cardiac adipose tissue change was -11.5 (95% confidence interval -17.6, -5.4) mL in the liraglutide (P < 0.001) and -0.01 (-5.3, 5.3) mL in the placebo (P = 1.00) groups. The reduction in cardiac adipose tissue was significantly greater in the liraglutide compared to the placebo group (mean difference -11.4 [-19.4, -3.3] mL; P = 0.006), but significance was lost after adjustment for changes in body mass index (P = 0.46).

CONCLUSION

Treatment with liraglutide for 26 weeks was associated with a reduction in cardiac adipose tissue compared to placebo. The reduction was not independent of weight loss, suggesting that this is not a drug-specific effect.

Effect of liraglutide on expression of inflammatory genes in type 2 diabetes

Anti-inflammatory effects of glucagon-like peptide 1 receptor agonist (GLP-1 RA) treatment in T2D may contribute to the cardiovascular benefits observed with GLP-1 RAs in outcome studies. We investigated if the GLP-1 RA liraglutide exerts anti-inflammatory effects through modulation of inflammatory gene expression in peripheral blood mononuclear cells (PBMCs). From 54 participants of a double-blinded trial where individuals with type 2 diabetes (T2D) were randomized to liraglutide (1.8 mg/day) or placebo for 26 weeks, a sub-study was performed in which PBMCs were extracted from fresh blood at study start and at end-of-treatment. The expression of selected inflammatory genes in PBMCs were measured by quantitative real-time polymerase chain reaction (PCR). Moreover, the expression of the GLP-1 receptor (GLP1R) was examined in a subset (n = 40) of the PBMC samples. The human monocytic cell line THP-1 was used for in vitro GLP-1 exposure experiments. The expression of tumor necrosis factor-α (TNFA) (p = 0.004) and interleukin-1β (IL1B) was downregulated (p = 0.046) in the liraglutide-treated group (n = 31), and unchanged in the placebo group (n = 21, p ≥ 0.11), with no significant differences between the two groups (p ≥ 0.67). The expression of interferon-γ (IFNG) and cluster of differentiation 163 (CD163) were upregulated in both groups (p ≤ 0.006) with no differences between groups (p ≥ 0.47). C–C Motif Chemokine Ligand 5 (CCL5) was upregulated in the liraglutide-treated group (p = 0.002) and unchanged in the placebo group (p = 0.14), with no significant difference between groups (p = 0.36). Intercellular adhesion molecule 1 (ICAM1) was unchanged in both groups (p ≥ 0.43). GLP1R expression in the PBMCs was undetectable. In vitro experiments showed no effect of GLP-1 treatment on inflammatory gene expression in THP-1 cells. GLP1R expression in THP-1 cells was not detectable. In summary, we observed a discrete modulatory effect of liraglutide on the expression of inflammatory genes in PBMCs. The lack of evidence for GLP1R expression in PBMCs and THP-1 cells suggests that possible effects of liraglutide on the PBMCs’ gene expression are most likely indirect. Further investigations are needed to establish the anti-inflammatory potential of GLP-1 RAs.

Ceramides and phospholipids are downregulated with liraglutide treatment: results from the LiraFlame randomized controlled trial

INTRODUCTION

Treatment with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) can reduce risk of cardiovascular disease (CVD) in persons living with type 2 diabetes, however the mechanisms explaining this cardiovascular benefit are still debated. We investigated changes in the plasma lipidome following treatment with the GLP-1 RA liraglutide.

RESEARCH DESIGN AND METHODS

In a double-blind placebo-controlled trial, we randomized 102 persons with type 2 diabetes to liraglutide or placebo for 26 weeks. Fasting blood plasma was collected at baseline and at end-of-treatment. The lipidome was measured using liquid-chromatography-coupled mass-spectrometry as a secondary end point in the study. Treatment response of each lipid was tested with lipid-specific linear mixed-effect models comparing liraglutide with placebo. Bonferroni p<7.1e-03 was employed. The independence of the findings from clinical covariates was evaluated with adjustment for body mass index, HbA_1c, fasting status, lipid-lowering treatment and change in lipid-lowering treatment during the trial.

RESULTS

In total, 260 lipids were identified covering 11 lipid families. We observed significant decreases following liraglutide treatment compared with placebo in 21 lipids (p<7.1e-03) from the following lipid families: ceramides, hexocyl-ceramides, phosphatidylcholines, phosphatidylethanolamines and triglycerides. We confirmed these findings in adjusted models (p≤0.01). In the liraglutide-treated group, the individual lipids were reduced in the range of 14%-61% from baseline level, compared with 19% decrease to 27% increase from baseline level in the placebo group.

CONCLUSIONS

Compared with placebo, liraglutide treatment led to a significant downregulation in ceramides, phospholipids and triglycerides, which all are linked to higher risk of CVD. These findings were independent of relevant clinical covariates. Our findings are hypothesis generating and shed light on the biological mechanisms underlying the cardiovascular benefits observed with GLP-1 RAs in outcome studies, and further strengthen the evidence base for recommending GLP-1 RAs to prevent CVD in type 2 diabetes.

TRIAL REGISTRATION NUMBER

NCT03449654.

Effect of Liraglutide on Vascular Inflammation Evaluated by [64Cu]DOTATATE

Quantification of vascular inflammation before and after treatment with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) may help reveal mechanistic pathways underlying the cardiovascular benefits of these drugs. We assessed change in vascular inflammation in the carotid arteries over 26 weeks by copper-64-labeled [1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid]-D-Phe1, Tyr3-octreotate ([⁶⁴Cu]DOTATATE) PET in 30 participants included in a substudy of a double-blind trial where persons with type 2 diabetes (T2D) were randomized to liraglutide (n = 15) or placebo (n = 15) for 26 weeks. Mean age (SD) was 66.4 (7.2) years, HbA_1c 56.4 (9.2) mmol/mol and BMI 28.9 (4.6) kg/m². Weight and HbA_1c were significantly reduced by liraglutide vs. placebo (p ≤ 0.01). The [⁶⁴Cu]DOTATATE uptake (mean standardized uptake values) was significantly reduced in the liraglutide-treated group (−0.11 [95% confidence interval −0.19 to −0.03], p = 0.01) and not changed significantly in the placebo group (−0.07 [−0.14 to 0.01], p = 0.08). The mean difference between groups did not reach significance (−0.04 [−0.15 to 0.07], p = 0.44). In conclusion, [⁶⁴Cu]DOTATATE uptake was reduced in persons with T2D treated with liraglutide. However, the reduction compared to placebo did not reach statistical significance, perhaps due to limited power. A reduction in vascular inflammation with liraglutide could help explain the cardiovascular protection observed with GLP-1 RAs in outcome studies but warrants further and larger studies.

Effect of Liraglutide on Arterial Inflammation Assessed as [18F]FDG Uptake in Patients With Type 2 Diabetes: A Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND

The mechanism behind the cardiovascular protection observed with human GLP-1 RA (glucagon-like peptide-1 receptor agonists) in type 2 diabetes is unknown. We hypothesized that treatment with the GLP-1 RA liraglutide had a positive effect on vascular inflammation.

METHODS

LIRAFLAME (Effect of liraglutide on vascular inflammation in type-2 diabetes: A randomized, placebocontrolled, double-blind, parallel clinical PET/CT trial) was a double-blind, randomized controlled trial performed at a single university hospital clinic in Denmark. Patients with type 2 diabetes were via computer-generated randomization list assigned (1:1) liraglutide up to 1.8 mg or placebo once daily for 26 weeks. The primary end point was change in vascular inflammation over 26 weeks assessed by [¹⁸F]-fluorodeoxyglucose positron emission tomography/computed tomography. Analyses were based on intention-to-treat. Key secondary outcomes included change in other indices of atherosclerosis.

RESULTS

Between October 26, 2017, and August 16, 2019, 147 patients were screened and 102 were randomly assigned to liraglutide (n=51) or placebo (n=51) and 99 (97%) completed the trial. Change in the [¹⁸F]-fluorodeoxyglucose positron emission tomography measure of vascular inflammation (active-segment target-to-background ratio) did not differ between treatment groups: change from baseline to 26 weeks was -0.04 (95% CI, -0.17 to 0.08) in the liraglutide group compared with -0.09 (-0.19 to 0.01) in the placebo group (mean difference, 0.05 [95% CI, -0.11 to 0.21], P=0.53). Secondary analyses restricted to [¹⁸F]-fluorodeoxyglucose positron emission tomography of the carotid arteries as well as other indices of atherosclerosis confirmed the primary result. We performed an explorative analysis of interaction between treatment group and history of cardiovascular disease (P=0.052).

CONCLUSIONS

In this low to moderate risk population with type 2 diabetes, liraglutide did not change vascular inflammation assessed as [¹⁸F]-fluorodeoxyglucose uptake compared with placebo. An explorative analysis indicated a possible effect in persons with history of cardiovascular disease, in line with current guidelines where liraglutide is recommended to patients with history of cardiovascular disease. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03449654.

Non-invasive assessment of temporal changes in myocardial microvascular function in persons with type 2 diabetes and healthy controls

BACKGROUND

Cardiac Rubidium-82 (⁸² Rb) positron emission tomography/computed tomography (PET/CT) provides a measure of the myocardial blood flow and the myocardial flow reserve, which reflects the function of both large epicardial arteries and the myocardial microcirculation. Knowledge on changes in the myocardial microvascular function over time is lacking.

METHODS

In this cohort study, we recruited 60 persons with type 2 diabetes and 30 non-diabetic controls, in 2013; all free of overt cardiovascular disease. All underwent a cardiac ⁸² Rb PET/CT scan. In 2019, all survivors (n = 82) were invited for a repeated cardiac ⁸² Rb PET/CT scan using the same protocol, and 29 with type 2 diabetes and 19 controls participated.

RESULTS

Median duration between visits was 6.2 years (IQR: 6.1-6.3). In the total cohort, the mean age was 66.4 years (SD: 9.3) and 33% were females. The myocardial flow reserve was lower in persons with type 2 diabetes compared to controls (p = 0.002) but there was no temporal change in the myocardial flow reserve in participants with type 2 diabetes: mean change: -0.22 (95% CI: -0.47 to 0.02) nor in controls: -0.12 (-0.49 to 0.25) or when comparing type 2 diabetes to controls: mean difference: -0.10 (95% CI: -0.52 to 0.31). The temporal reduction in stress-induced myocardial blood flow did not differ within the groups but was more pronounced in type 2 diabetes compared to controls: mean difference: -0.30 (95% CI: -0.55 to -0.04).

CONCLUSION

The myocardial microvascular function was impaired in persons with type 2 diabetes compared to controls but did not change significantly in either of the groups when evaluated over 6 years.

Effect of 26 Weeks of Liraglutide Treatment on Coronary Artery Inflammation in Type 2 Diabetes Quantified by [64Cu]Cu-DOTATATE PET/CT: Results from the LIRAFLAME Trial

BACKGROUND

Quantification of coronary artery inflammation and atherosclerosis remains a challenge in high-risk individuals. In this study we sought to investigate if the glucagon like peptide-1 receptor agonist liraglutide has a direct anti-inflammatory effect in the coronary arteries using positron emission tomography (PET) with a radioactive tracer targeting activated macrophages in the vessel-wall.

METHODS

Thirty randomly selected participants with type 2 diabetes from the placebo-controlled trial LIRAFLAME were enrolled in this sub-study. Participants were, prior to enrollment in this sub-study, randomized to either treatment with daily liraglutide (n=15) or placebo (n=15). Both groups underwent a combined [⁶⁴Cu]Cu-DOTATATE positron emission tomography and computed tomography scan of the heart at baseline and after 26 weeks of treatment. Coronary artery uptake of [⁶⁴Cu]Cu-DOTATATE were measured as maximum standardized uptake values (SUV_max); and means of the maximum values (mSUV_max), both values were calculated at the level of each participant and each individual coronary-segment.

RESULTS

SUV_max and mSUV_max values decreased significantly in the liraglutide group both at the participant level (SUV_max: p=0.013; mSUV_max: p=0.004) and at the coronary-segment level (SUV_max: p=0.001; mSUV_max: p<0.0001). No change was observed in the placebo group neither at the participant level (SUV_max: p=0.69; mSUV_max: p=0.67) or at the coronary-segment level (SUV_max: p=0.49; mSUV_max: p=0.30). When comparing the mean change in uptake values between the two groups at both the participant level (SUV_max: p=0.076; mSUV_max: p=0.077) and the coronary segment level (SUV_max: p=0.13; mSUV_max: p=0.11) a borderline significant difference was observed. Baseline SUV_max [⁶⁴Cu]Cu-DOTATATE uptake values showed a weak positive correlation with the inflammatory biomarker high-sensitivity c-reactive protein (τ =0.26, p=0.045).

CONCLUSION

Liraglutide treatment for 26-weeks caused a significant reduction in [⁶⁴Cu]Cu-DOTATATE uptake in the coronary arteries whereas this was not seen in the placebo treated group. In addition, [⁶⁴Cu]Cu-DOTATATE PET/CT as a marker of coronary inflammation correlated with the systemic inflammation marker hs-CRP.

Myocardial flow reserve assessed by cardiac 82Rb positron emission tomography/computed tomography is associated with albumin excretion in patients with Type 1 diabetes

AIMS

To evaluate myocardial flow reserve (MFR) and coronary artery calcium (CAC) in persons with Type 1 diabetes with or without albuminuria and in non-diabetic controls. MFR reflects the function of large epicardial arteries and myocardial microcirculation. CAC represents structural aspects of atherosclerosis. In addition, we evaluated the association of MFR and CAC with retinopathy, another microvascular complication.

METHODS AND RESULTS

Cross-sectional study in Type 1 diabetes, stratified by normoalbuminuria (NORMO; n = 30) and macroalbuminuria (MACRO; n = 30), and in non-diabetic controls (n = 30). MFR (pharmacological stress flow/rest flow) was evaluated by cardiac 82Rb positron emission tomography/computed tomography. MFR was similar in patients with NORMO and controls (3.1 ± 0.79 vs. 3.0 ± 0.79; P = 0.74). Patients with MACRO had lower (impaired) MFR when compared with NORMO (2.1 ± 0.92 vs. 3.1 ± 0.79; P < 0.0001). The CAC score [median (interquartile range)] was higher in NORMO when compared with controls [72 (22-247) vs. 0 (0-81), P = 0.03], and comparable between MACRO and NORMO. MFR was comparable in patients with diabetes and simplex or no retinopathy (n = 24 and n = 12, 2.8 ± 0.84 vs. 3.3 ± 0.77, P = 0.11), but lower in proliferative (n = 24) compared with simplex retinopathy (2.1 ± 0.97 vs. 2.8 ± 0.84, P = 0.02). The CAC score was comparable between groups of retinopathy.

CONCLUSION

Myocardial microvascular function was comparable in non-diabetic controls and patients with Type 1 diabetes and NORMO; but impaired in the presence of microvascular complications (MACRO and proliferative retinopathy). Coronary calcification was elevated in diabetes, however, not explained by albuminuria.

Relation of cardiac adipose tissue to coronary calcification and myocardial microvascular function in type 1 and type 2 diabetes

Background

Cardiac adipose tissue may have local paracrine effects on epicardial arteries and the underlying myocardium, promoting calcification and affecting myocardial microcirculation. We explored whether the total amount of cardiac adipose tissue was associated with coronary artery calcium score (CAC) and myocardial flow reserve in persons with type 1 or type 2 diabetes and healthy controls.

Methods

We studied three groups: (1) 30 controls, (2) 60 persons with type 1 diabetes and (3) 60 persons with type 2 diabetes. The three groups were matched for sex and age. The three groups derived from retrospective analysis of two clinical studies. All underwent cardiac ⁸²Rb positron emission tomography/computed tomography (PET/CT) scanning. Cardiac adipose tissue volume (the sum of epicardial and pericardial fat), CAC, and myocardial flow reserve (ratio of pharmacological stress flow and rest flow) were evaluated using semiautomatic software. We applied linear regression to assess the association between cardiac adipose tissue, CAC and myocardial flow reserve.

Results

Mean (SD) cardiac adipose tissue volume was 99 (61) mL in the control group, 106 (78) mL in the type 1 diabetes group and 228 (97) mL in the type 2 diabetes group. Cardiac adipose tissue was positively associated with body mass index in all three groups (p ≤ 0.02). In the controls, cardiac adipose tissue was positively associated with CAC score (p = 0.008) and negatively associated with myocardial flow reserve (p = 0.005). However, cardiac adipose tissue was not associated with CAC or myocardial flow reserve in the groups including persons with type 1 or type 2 diabetes (p ≥ 0.50).

Conclusions

In contrast to what was found in healthy controls, we could not establish a relation between cardiac adipose tissue and coronary calcification or myocardial microvascular function in person with type 1 or type 2 diabetes. The role of cardiac adipose tissue in cardiovascular disease in diabetes remains unclear.

Cardiac Autonomic Function Is Associated With Myocardial Flow Reserve in Type 1 Diabetes

The link between cardiac autonomic neuropathy and risk of cardiovascular disease is highlighted as an area in which research is needed. This study was undertaken to evaluate the association between measures of cardiac autonomic function and cardiac vascular function in type 1 diabetes using new and sensitive methods. This was a cross-sectional study in patients with type 1 diabetes, stratified by normoalbuminuria (n = 30) and macroalbuminuria (n = 30), and in healthy control subjects (n = 30). Cardiac autonomic function was evaluated using heart rate variability (HRV) indices, cardiovascular autonomic reflex tests (CARTs), and cardiac ¹²³I-metaiodobenzylguanidine (MIBG) imaging. Cardiac vascular function was assessed as myocardial flow reserve (MFR) measured by cardiac ⁸²Rb-positron emission tomography/computed tomography. The measures of cardiac autonomic function (except low frequency-to-high frequency ratio and the Valsalva test ratio) were positively correlated to MFR in unadjusted analysis. All the HRV indices lost significance after adjustment for age and heart rate. After further adjustment for relevant cardiovascular risk factors, the late heart-to-mediastinum ratio directly measuring the function of adrenergic receptors and sympathetic integrity (from the MIBG scintigraphy) and the 30-to-15 ratio (a CART), remained positively associated with MFR (P ≤ 0.04). Cardiac autonomic dysfunction, including loss of cardiac sympathetic integrity in type 1 diabetes, is associated with and may contribute to impaired myocardial blood flow regulation.

Pleiotropic effects of liraglutide in patients with type 2 diabetes and moderate renal impairment: Individual effects of treatment

Liraglutide has pleiotropic effects favouring cardiovascular and renal risks. We investigated individual responses to liraglutide in six cardio-renal risk factors to examine whether responses in one risk factor are associated with changes in other risk factors (cross-dependency). We performed secondary analysis of the LIRA-RENAL trial (n = 279) in type 2 diabetes. HbA1c, body weight, systolic blood pressure (SBP)_, low density lipoprotein (LDL)-cholesterol, urine albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) were measured at baseline and after 26 weeks of liraglutide/placebo treatment: "Good responders" had a change within the best quartile. In the liraglutide-treated group, good HbA1c responders showed similar changes in other risk factors analysed to low responders (P ≥ 0.17). Good body weight responders had a larger reduction in HbA1c than low body weight responders (-1.6 ± 0.94 vs. -1.0 ± 0.82%; P = 0.003), but similar changes in the other risk factors (P ≥ 0.11). Good and low responders in SBP, UACR, LDL-cholesterol or eGFR showed similar changes in other risk factors (P ≥ 0.07). Treatment response to liraglutide is largely individual; aside from an association between body weight and HbA1c reduction, there are no obvious cross-dependencies in risk factor response.

Higher Collagen VI Formation Is Associated With All-Cause Mortality in Patients With Type 2 Diabetes and Microalbuminuria

OBJECTIVE

Type 2 diabetes is a common risk factor for the development of chronic kidney disease (CKD). Enhanced de novo collagen type VI (COL VI) formation has been associated with renal fibrosis and CKD. We investigated the hypothesis that PRO-C6, a product specifically generated during COL VI formation, is prognostic for adverse outcomes in patients with type 2 diabetes and microalbuminuria.

RESEARCH DESIGN AND METHODS

In a prospective, observational study, we measured PRO-C6 in the serum (S-PRO-C6) and urine (U-PRO-C6) of 198 patients with type 2 diabetes and microalbuminuria without symptoms of coronary artery disease. Patients were followed for a median of 6.5 years, and end points were a composite of cardiovascular events (n = 38), all-cause mortality (n = 26), and reduction of estimated glomerular filtration rate (eGFR) of >30% (disease progression [n = 42]). Cox models were unadjusted and adjusted for the conventional risk factors of sex, age, BMI, systolic blood pressure, LDL cholesterol, smoking, HbA_1c, plasma creatinine, and urinary albumin excretion rate.

RESULTS

Doubling of S-PRO-C6 increased hazards for cardiovascular events (hazard ratio 3.06 [95% CI 1.31-7.14]), all-cause mortality (6.91 [2.96-16.11]), and disease progression (4.81 [1.92-12.01]). Addition of S-PRO-C6 to a model containing conventional risk factors improved relative integrated discrimination by 22.5% for cardiovascular events (P = 0.02), 76.8% for all-cause mortality (P = 0.002), and 53.3% for disease progression (P = 0.004). U-PRO-C6 was not significantly associated with any of the outcomes.

CONCLUSIONS

S-PRO-C6 generated during COL VI formation predicts cardiovascular events, all-cause mortality, and disease progression in patients with type 2 diabetes and microalbuminuria.

No Evidence of Increase in Calcitonin Concentrations or Development of C-Cell Malignancy in Response to Liraglutide for Up to 5 Years in the LEADER Trial

OBJECTIVE

To describe the changes in serum levels of calcitonin in liraglutide- and placebo-treated patients in the Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results-A Long Term Evaluation (LEADER) trial over a 3.5-5-year period.

RESEARCH DESIGN AND METHODS

Patients (n = 9,340) with type 2 diabetes and high risk for cardiovascular events were randomized 1:1 to liraglutide or placebo. We analyzed calcitonin levels, thyroid and C-cell adverse events, and neoplasms.

RESULTS

At 36 months, patients randomized to liraglutide versus placebo showed no evidence of increase in calcitonin concentrations in male (estimated treatment ratio [ETR] 1.03 [95% CI 1.00, 1.06]; P = 0.068) and female (ETR 1.00 [95% CI 0.97, 1.02]; P = 0.671) subgroups. There were no episodes of C-cell hyperplasia or medullary thyroid carcinoma in liraglutide-treated patients.

CONCLUSIONS

There was no evidence of a difference in calcitonin concentrations between the liraglutide and placebo groups, and no C-cell malignancies occurred in the liraglutide group.

Abstract P142: The CKD273 Urinary Peptidomic Biomarker is Associated with Mortality in People at Early Stages of Diabetic Nephropathy Independent of Traditional Risk Factors

Background: Mortality in type 2 diabetes (T2D) is primarily driven by cardiovascular disease. This is amplified in diabetic nephropathy (DN), even in early ‘pre-clinical’ stages. A urinary peptidomic classifier (CKD273) has been found to predict DN development in advance of detectable microalbuminuria. Whether it is also a determinant of mortality and cardiovascular disease in patients with established albuminuria is unknown.

Methods: We studied 155 subjects with T2D, albuminuria (geometrical mean [IQR]: 85 [34;194] mg/24hrs), controlled blood pressure (129±16/74±11 mmHg) and preserved renal function (eGFR 88±17 ml/min/1.73m 2 ). Blood and urine samples were collected for measurement of estimated glomerular filtration rate (eGFR), urine albumin excretion (UAE), N-terminal pro-brain natriuretic peptide (NT-proBNP; ELISA) and urinary proteomics (capillary electrophoresis coupled to mass spectrometry). Computed tomography imaging was performed to assess coronary artery calcium (CAC) score. Outcome data were collected through national disease registries over a 6 year follow up period.

Results: CKD273 correlated with UAE (r=0.481, p=<0.001), age (r=0.238, p=0.003), CAC score (r=0.236, p=0.003), NT-proBNP (r=0.190, p=0.018) and eGFR (r=0.265, p=0.001). On multiple regression only UAE (β=0.402, p<0.001) and eGFR (β=-0.184, p=0.039) were statistically significant determinants. Twenty participants died during follow-up. CKD273 was a determinant of mortality (log rank [Mantel-Cox] p=0.004), and retained significance (p=0.050) after adjustment for age, sex, blood pressure, NT-proBNP and CAC score in a Cox regression model. Neither eGFR nor UAE were determinants of mortality in this cohort.

Conclusions: A multidimensional biomarker can provide information on outcomes associated with its primary diagnostic purpose. Here we demonstrate that the peptidomics-based classifier CKD273 is associated with mortality in albuminuric people with T2D in even when adjusted for other established cardiovascular and renal biomarkers.

Epicardial, pericardial and total cardiac fat and cardiovascular disease in type 2 diabetic patients with elevated urinary albumin excretion rate

Background We evaluated the association of cardiac adipose tissue including epicardial adipose tissue and pericardial adipose tissue with incident cardiovascular disease and mortality, coronary artery calcium, carotid intima media thickness and inflammatory markers. Design A prospective study of 200 patients with type 2 diabetes and elevated urinary albumin excretion rate (UAER). Methods Cardiac adipose tissue was measured from baseline echocardiography. The composite endpoint comprised incident cardiovascular disease and all-cause mortality. Coronary artery calcium, carotid intima media thickness and inflammatory markers were measured at baseline. Cardiac adipose tissue was investigated as continuous and binary variable. Analyses were performed unadjusted (model 1), and adjusted for age, sex (model 2), body mass index, low-density lipoprotein cholesterol, smoking, glycated haemoglobin, and systolic blood pressure (model 3). Results Patients were followed-up after 6.1 years for non-fatal cardiovascular disease ( n = 29) or mortality ( n = 23). Cardiac adipose tissue ( p = 0.049) and epicardial adipose tissue ( p = 0.029) were associated with cardiovascular disease and mortality in model 1. When split by the median, patients with high cardiac adipose tissue had a higher risk of cardiovascular disease and mortality than patients with low cardiac adipose tissue in unadjusted (hazard ratio 1.9, confidence interval: 1.1; 3.4, p = 0.027) and adjusted (hazard ratio 2.0, confidence interval: 1.1; 3.7, p = 0.017) models. Cardiac adipose tissue ( p =  0.033) was associated with baseline coronary artery calcium (model 1) and interleukin-8 (models 1-3, all p < 0.039). Conclusions In type 2 diabetes patients without coronary artery disease, high cardiac adipose tissue levels were associated with increased risk of incident cardiovascular disease or all-cause mortality even after accounting for traditional cardiovascular disease risk factors. High cardiac adipose tissue amounts were associated with subclinical atherosclerosis (coronary artery calcium) and with the pro-atherogenic inflammatory marker interleukin-8.

The effect of liraglutide on renal function: A randomized clinical trial

AIMS

Among patients with type 2 diabetes and albuminuria, cardiorenal morbidity and mortality are high despite multifactorial treatment. Short-term reduction in albuminuria is considered suggestive of long-term renoprotective effects. We evaluated the renal effects of the glucagon-like peptide-1 (GLP-1) receptor agonist liraglutide on top of multifactorial care, including renin-angiotensin-system (RAS)-inhibition.

MATERIALS AND METHODS

Randomized, double-blind, placebo-controlled, cross-over trial including patients with type 2 diabetes and persistent albuminuria (urinary albumin-to-creatinine ratio >30 mg/g) and estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m² . Patients received liraglutide (1.8 mg/d) and matched placebo for 12 weeks in a random order. The primary endpoint was change in 24-h urinary albumin excretion rate (UAER).

RESULTS

A total of 32 patients were randomized and 27 completed the study. After placebo treatment, geometric mean (IQR) UAER was 199 (81-531) mg/24-h, mean (SD) measured GFR (mGFR) 75 (36) mL/min/1.73 m² , 24-h blood pressure 145/80 (15/8) mm Hg and HbA1c 61 (11) mmol/mol. Liraglutide reduced HbA1c by 8 (95% CI: 5; 11) mmol/mol (P < .001) and weight by 1.8 (95% CI: 0.2; 3.4) kg (P = .032) compared to placebo. Furthermore, liraglutide reduced UAER by 32 (95% CI: 7; 50)% ( P = .017) compared with placebo. The change in mGFR was -5 (95% CI: -11; 2) mL/min/1.73 m² ( P = .15), and change in 24-h systolic blood pressure was -5 (95% CI: -10; 0) mm Hg ( P = .07). In multivariate regression models, change in UAER was associated with change in 24-h systolic blood pressure ( P = .025) but not with change in HbA1c, weight or mGFR ( P ≥ .14), overall model R ² = .39.

CONCLUSIONS

Our placebo-controlled randomized trial suggests that liraglutide has renoprotective effects on top of multifactorial treatment, including RAS-inhibition, in patients with type 2 diabetes and albuminuria.

High osteoprotegerin is associated with development of foot ulcer in type 1 diabetes

BACKGROUND AND AIM

The bone-related peptide osteoprotegerin has been linked to vascular calcification and peripheral vascular disease. We investigated the association between osteoprotegerin and development of foot complications in persons with type 1 diabetes.

MATERIALS AND METHODS

Prospective observational study of 573 persons with type 1 diabetes, 225 women; age [mean±SD] 42.3±10.3years. Plasma osteoprotegerin was measured by ELISA.

RESULTS

Median (IQR) osteoprotegerin was 2.80(2.35-3.63)μg/L and follow-up time (median (range)) was 12.7(0.1-15.6)years. Endpoints included: new foot ulceration (n=153), Charcot foot (n=14), vascular surgery/amputation (n=53), loss of foot pulse (n=57), and peripheral neuropathy (n=99). In unadjusted analyses, higher osteoprotegerin was associated with development of all endpoints (p≤0.026). Higher osteoprotegerin remained associated with development of foot ulcer, and the combination of vascular surgery/amputation, loss of foot pulse and neuropathy (p≤0.001) in a sex and age adjusted model. After further adjustment (nephropathy status, smoking, HbA_1c, systolic blood pressure, serum cholesterol, high sensitivity C-reactive protein, eGFR, and presence of neuropathy and/or claudication and/or foot ulcer at baseline), higher osteoprotegerin remained associated with development of foot ulcer (HR (95% CI) per doubling: 1.75 (1.04-2.97); p=0.037).

CONCLUSION

Higher osteoprotegerin levels were associated with development of foot ulcer, even after comprehensive adjustment.

Cardiac (82)Rb PET/CT for fast and non-invasive assessment of microvascular function and structure in asymptomatic patients with type 2 diabetes

AIMS/HYPOTHESIS

Coronary flow reserve (CFR) and coronary artery calcium (CAC) represent functional and structural aspects of atherosclerosis. We examined the prevalence of reduced CFR and high CAC scores in three predefined groups of participants without known cardiovascular disease: (1) patients with type 2 diabetes and albuminuria; (2) patients with type 2 diabetes and normoalbuminuria; and (3) non-diabetic controls.

METHODS

In a cross-sectional design, cardiac (82)Rb positron emission tomography/computed tomography was conducted in 60 patients with type 2 diabetes who were free of overt cardiovascular disease and who were stratified by normoalbuminuria (<30 mg/24 h) (n = 30; age [mean ± SD] 60.9 ± 10.1 years) and albuminuria (≥ 30 mg/24 h) (n = 30; age 65.6 ± 4.8 years), and in 30 healthy, non-diabetic controls (age 59.8 ± 9.9 years).

RESULTS

In controls, normoalbuminuric and albuminuric patients, CFR was 3.0 ± 0.8, 2.6 ± 0.8 and 2.0 ± 0.5, respectively. Reduced CFR (<2.5) was observed in 16.7%, 40.0% and 83.3% of participants, respectively, and median (interquartile range) CAC scores were 0 (0-81), 36 (1-325) and 370 (152-1,025), respectively (p for trend <0.01). After adjustment, the difference in CFR and CAC between albuminuric patients and controls remained significant (p ≤ 0.001). There were trends towards lower CFR and higher CAC scores in normoalbuminuric patients vs controls (p ≤ 0.023) and towards higher CAC scores in albuminuric vs normoalbuminuric patients (p = 0.026). In multivariate regression analysis, a higher urinary albumin excretion rate (UAER) tended to predict reduced CFR in the total population (p = 0.045). When the CAC score was added, there was also a trend (p = 0.032) towards an inverse association with reduced CFR.

CONCLUSIONS/INTERPRETATION

Type 2 diabetic patients who were free of overt cardiovascular disease had a high prevalence of coronary microvascular dysfunction, especially with concomitant albuminuria, suggesting a common microvascular impairment occurring in multiple microvascular beds. Prospective studies are needed to show the prognostic significance of this finding.