Impaired kidney function is associated with worse cardiovascular outcomes. Sitagliptin has no clinically significant impact on cardiovascular or CKD outcomes, irrespective of baseline eGFR.

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.

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.

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 threestep 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.

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