Sitagliptin does not reduce the risk of cardiovascular death or hospitalization for heart failure following myocardial infarction in patients with diabetes: observations from TECOS.

BACKGROUND: To examine the effects of the DPP-4i sitagliptin on CV outcomes during and after incident MI in the Trial Evaluating Cardiovascular Outcomes with Sitagliptin (TECOS). METHODS: TECOS randomized 14,671 participants with type 2 diabetes and atherosclerotic cardiovascular disease (ASCVD) to sitagliptin or placebo, in addition to usual care. For those who had a within-trial MI, we analyzed case fatality, and for those with a nonfatal MI, we examined a composite cardiovascular (CV) outcome (CV death or hospitalization for heart failure [hHF]) by treatment group, using Cox proportional hazards models left-censored at the time of the first within-trial MI, without and with adjustment for potential confounders, in intention-to-treat analyses. RESULTS: During TECOS, 616 participants had ≥ 1 MI (sitagliptin group 300, placebo group 316, HR 0.95, 95% CI 0.81-1.11, P = 0.49), of which 25 were fatal [11 and 14, respectively]). Of the 591 patients with a nonfatal MI, 87 (15%) died subsequently, with 66 (11%) being CV deaths, and 57 (10%) experiencing hHF. The composite outcome occurred in 58 (20.1%; 13.9 per 100 person-years) sitagliptin group participants and 50 (16.6%; 11.7 per 100 person-years) placebo group participants (HR 1.21, 95% CI 0.83-1.77, P = 0.32, adjusted HR 1.23, 95% CI 0.83-1.82, P = 0.31). On-treatment sensitivity analyses also showed no significant between-group differences in post-MI outcomes. CONCLUSIONS: In patients with type 2 diabetes and ASCVD experiencing an MI, sitagliptin did not reduce subsequent risk of CV death or hHF, contrary to expectations derived from preclinical animal models. Trial registration clinicaltrials.gov no. NCT00790205.

Longitudinal medical resources and costs among type 2 diabetes patients participating in the Trial Evaluating Cardiovascular Outcomes with Sitagliptin (TECOS).

AIMS: TECOS, a cardiovascular safety trial (ClinicalTrials.gov identifier: NCT00790205) involving 14 671 patients with type 2 diabetes and cardiovascular disease, demonstrated that sitagliptin was non-inferior to placebo for the primary composite cardiovascular outcome when added to best usual care. This study tested hypotheses that medical resource use and costs differed between these 2 treatment strategies. MATERIALS AND METHODS: Information concerning medical resource use was collected on case report forms throughout the trial and was valued using US costs for: Medicare payments for hospitalizations, medical procedures and outpatient visits, and wholesale acquisition costs (WAC) for diabetes-related medications. Hierarchical generalized linear models were used to compare resource use and US costs, accounting for variable intercountry practice patterns. Sensitivity analyses included resource valuation using English costs for a UK perspective. RESULTS: There were no significant differences in hospitalizations, inpatient days, medical procedures, or outpatient visits during follow-up (mean and median 3.0 years in both groups). Hospitalization rates appeared to diverge after 2 years, with lower rates among sitagliptin-treated vs placebo patients after 2.5 years (relative rate, 0.90 [95% CI, 0.83-0.97]; P = .01). Mean medical costs, exclusive of study medication, were 11 937 USD in the sitagliptin arm and 12 409 USD in the placebo arm (P = .06). Mean sitagliptin costs based on undiscounted WAC were 9978 USD per patient. Differential UK total costs including study drug costs were smaller (911 GBP), primarily because of lower mean costs for sitagliptin (1072 GBP). CONCLUSIONS: Lower hospitalization rates across time with sitagliptin slightly offset sitagliptin treatment costs over 3 years in type 2 diabetes patients at high risk for cardiovascular events.

Safety of sitagliptin in patients with type 2 diabetes and chronic kidney disease: outcomes from TECOS.

AIMS: To characterize the incidence of diabetes-associated complications and assess the safety of sitagliptin in participants with chronic kidney disease (CKD) in the Trial Evaluating Cardiovascular Outcomes with Sitagliptin (TECOS). MATERIALS AND METHODS: For participants with baseline eGFR measurements (n = 14 528), baseline characteristics and safety outcomes were compared for the CKD cohort (eGFR < 60 mL/min per 1.73 m2 ) vs those without CKD. Within the CKD cohort, the same analyses were performed, comparing sitagliptin- and placebo-assigned participants. Baseline characteristics were summarized for all participants, and serious adverse events were analysed in those who received at least 1 dose of study medication. Adverse events of interest and diabetes complications were summarized for the intention-to-treat population. RESULTS: CKD was present in 3324 (23%) participants at entry into TECOS. The mean (SD) age for this CKD cohort was 68.8 (7.9) years, mean diabetes duration was 13.7 (9.0) years, and 62% were men. Incidences of serious adverse events, malignancy, bone fracture, severe hypoglycaemia and most categories of diabetes complications were higher in the CKD cohort compared with those without CKD. Over ~2.8 median years of follow-up, CKD participants assigned to sitagliptin had rates of diabetic eye disease, diabetic neuropathy, renal failure, malignancy, bone fracture, pancreatitis and severe hypoglycaemia similar to those of placebo-assigned participants. CONCLUSIONS: Participants in TECOS with CKD had higher incidences of serious adverse events and diabetes complications than those without CKD. Treatment with sitagliptin was generally well tolerated, with no meaningful differences in safety outcomes observed between those with CKD assigned to sitagliptin or placebo.

Effect of Sitagliptin on Kidney Function and Respective Cardiovascular Outcomes in Type 2 Diabetes: Outcomes From TECOS.

OBJECTIVE: To evaluate chronic kidney disease (CKD) and cardiovascular outcomes in TECOS (Clinical trial reg. no. NCT00790205, clinicaltrials.gov) participants with type 2 diabetes and cardiovascular disease treated with sitagliptin, a dipeptidyl peptidase 4 inhibitor, according to baseline estimated glomerular filtration rate (eGFR). RESEARCH DESIGN AND METHODS: We used data from 14,671 TECOS participants assigned in a double-blind design to receive sitagliptin or placebo added to existing therapy, while aiming for glycemic equipoise between groups. Cardiovascular and CKD outcomes were evaluated over a median period of 3 years, with participants categorized at baseline into eGFR stages 1, 2, 3a, and 3b (≥90, 60-89, 45-59, or 30-44 mL/min/1.73 m2, respectively). RESULTS: Participants with eGFR stage 3b were older, were more often female, and had a longer duration of diabetes. Four-point major adverse cardiovascular event rates increased with lower baseline eGFR (3.52, 3.55, 5.74, and 7.34 events/100 patient-years for stages 1-3b, respectively). Corresponding adjusted hazard ratios for stages 2, 3a, and 3b versus stage 1 were 0.93 (95% CI 0.82-1.06), 1.28 (1.10-1.49), and 1.39 (1.13-1.72), respectively. Sitagliptin therapy was not associated with cardiovascular outcomes for any eGFR stage (interaction P values were all >0.44). Kidney function declined at the same rate in both treatment groups, with a marginally lower but constant eGFR difference (-1.3 mL/min/1.73 m2) in those participants who were assigned to sitagliptin. Treatment differences in these eGFR values remained after adjustment for region, baseline eGFR, baseline HbA1c, time of assessment, and within-study HbA1c levels. CONCLUSIONS: Impaired kidney function is associated with worse cardiovascular outcomes. Sitagliptin has no clinically significant impact on cardiovascular or CKD outcomes, irrespective of baseline eGFR.

The effect of glibenclamide on insulin secretion at normal glucose concentrations.

AIMS/HYPOTHESIS: The aim of this study was to investigate the incremental and proportional effect of a sulfonylurea on insulin secretion rates at low, elevated and high blood glucose, using parallel groups with ascending or descending glucose steps to minimise potential biases of a single stepped clamp order. METHODS: Following 14 days on placebo or glibenclamide (2.5 mg) tablets twice daily, separated by 14 days washout, 19 type 2 diabetic patients had ascending or descending three-step hyperinsulinaemic glucose clamps at 4, 8 and 12 mmol/l. C-peptide secretion was estimated by two-compartment C-peptide deconvolution. RESULTS: Patients in the ascending glucose steps group (n = 10) had mean (SD) age of 60.3 (6.5) years, BMI of 29.8 (4.9) kg/m(2) and fasting glucose on diet alone of 10.6 (2.9) mmol/l; while those in the descending glucose steps group (n = 9) had mean age of 58.2 (8.0) years, BMI of 30.5 (5.4) kg/m(2) and fasting glucose on diet alone of 9.8 (2.2) mmol/l. The geometric means (95% CI) of C-peptide secretion rates on placebo for glucose at 4.0, 8.0 and 12.0 mmol/l were 63 (46, 86), 143 (105, 195) and 205 (149, 281) pmol/min, respectively. On glibenclamide, this increased by 140 (99, 181), 126 (85, 167) and 158 (117, 199) pmol/min, respectively (p < 0.001 vs placebo). The absolute increment was significant (p < 0.001) and independent of clamp glucose concentration (p = 0.54). The proportional increase was greater at 4 mmol/l: 2.8-fold (2.4, 3.2), compared with 1.8-fold (1.5, 2.0) and 1.7-fold (1.4, 1.9) at 8 and 12 mmol/l, respectively (p < 0.001). CONCLUSIONS/INTERPRETATION: At low-normal glucose, glibenclamide exerted a disproportionate effect on insulin secretion. This study highlights the risks of hypoglycaemia when aiming for tight glucose control on this agent.

Cardiac energetics correlates to myocardial hypertrophy in Friedreich's ataxia.

Friedreich's ataxia is a neurodegenerative disease frequently associated with hypertrophic cardiomyopathy. We have determined mitochondrial ATP, phosphocreatine, and intracellular inorganic phosphate levels by 31P nuclear magnetic resonance spectroscopy in the heart of 11 Friedreich's ataxia patients and 11 healthy controls. For the first time, to our knowledge, we showed a significant correlation between the extent of myocardial energy deficiency and the degree of myocardial hypertrophy. When combining our results with previous works on Friedreich's ataxia, these novel findings suggest that energy metabolism is most likely the cause and hypertrophy the effect in Friedreich's ataxia.