Mechanisms underlying the blood pressure lowering effects of dapagliflozin, exenatide, and their combination in people with type 2 diabetes: a secondary analysis of a randomized trial.

BACKGROUND: Sodium-glucose cotransporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RA) lower blood pressure (BP). When SGLT2i and GLP-1RA are combined, synergistic effects on BP have been observed. The mechanisms underlying these BP reductions are incompletely understood. The aim of this study was to assess the mechanisms underlying the BP reduction with the SGLT2i dapagliflozin, GLP-1RA exenatide, and dapagliflozin-exenatide compared with placebo in people with obesity and type 2 diabetes. METHODS: Sixty-six people with type 2 diabetes were randomized to 16 weeks of dapagliflozin 10 mg/day, exenatide 10 µg twice daily, dapagliflozin-exenatide, or placebo treatment. The effect of treatments on estimates of: (1) plasma volume (calculated by Strauss formula, bioimpedance spectroscopy, hematocrit, (2) autonomic nervous system activity (heart rate variability), (3) arterial stiffness (pulse wave applanometry), (4) systemic hemodynamic parameters including peripheral vascular resistance, cardiac output and stroke volume (all derived from non-invasively systemic hemodynamic monitoring), and (5) natriuresis (24-hour urine collection) were assessed after 10 days and 16 weeks of treatment. RESULTS: After 10 days, dapagliflozin reduced systolic BP (SBP) by - 4.7 mmHg, and reduced plasma volume. After 16 weeks, dapagliflozin reduced SBP by - 4.4 mmHg, and reduced sympathetic nervous system (SNS) activity. Exenatide had no effect on SBP, but reduced parasympathetic nervous system activity after 10 days and 16 weeks. After 10 days, dapagliflozin-exenatide reduced SBP by - 4.2 mmHg, and reduced plasma volume. After 16 weeks, dapagliflozin-exenatide reduced SBP by - 6.8 mmHg, and the reduction in plasma volume was still observed, but SNS activity was unaffected. CONCLUSIONS: The dapagliflozin-induced plasma volume contraction may contribute to the initial SBP reduction, while a reduction in SNS activity may contribute to the persistent SBP reduction. Dapagliflozin-exenatide resulted in the largest decrease in SBP. The effect on plasma volume was comparable to dapagliflozin monotherapy, and SNS activity was not reduced, therefore other mechanisms are likely to contribute to the blood pressure lowering effect of this combination, which need further investigation. Trial registration Clinicaltrials.gov, NCT03361098.

Combination therapy with exenatide decreases the dapagliflozin-induced changes in brain responses to anticipation and consumption of palatable food in patients with type 2 diabetes: A randomized controlled trial.

AIMS: Sodium-glucose cotransporter-2 inhibitors induce less weight loss than expected. This may be explained by sodium-glucose cotransporter-2 inhibitor-induced alterations in central reward- and satiety circuits, leading to increased appetite and food intake. Glucagon-like peptide-1 receptor agonists reduce appetite and body weight because of direct and indirect effects on the brain. We investigated the separate and combined effects of dapagliflozin and exenatide on the brain in response to the anticipation and consumption of food in people with obesity and type 2 diabetes. MATERIALS AND METHODS: As part of a larger study, this was a 16 week, double-blind, randomized, placebo-controlled trial. Subjects with obesity and type 2 diabetes were randomized (1:1:1:1) to dapagliflozin 10 mg with exenatide-matched placebo, exenatide twice-daily 10 µg with dapagliflozin-matched placebo, dapagliflozin plus exenatide, or double placebo. Using functional magnetic resonance imaging, the effects of treatments on brain responses to the anticipation of food and food receipt were assessed after 10 days and 16 weeks. RESULTS: After 10 days, dapagliflozin increased activation in right amygdala and right caudate nucleus in response to the anticipation of food, and tended to decrease activation in right amygdala in response to actual food receipt. After 16 weeks, no changes in brain activation were observed with dapagliflozin. Dapagliflozin plus exenatide reduced activation in right caudate nucleus and amygdala to the anticipation of food, and decreased activation in the right amygdala in response to food receipt after 16 weeks. CONCLUSIONS: The dapagliflozin-induced changes in brain activation may contribute to the discrepancy between observed and expected weight loss with dapagliflozin. Exenatide blunted the dapagliflozin-induced changes in brain activation, which may contribute to the additional weight loss with combined treatment.

Postprandial renal haemodynamic effects of the dipeptidyl peptidase-4 inhibitor linagliptin versus the sulphonylurea glimepiride in adults with type 2 diabetes (RENALIS): A predefined substudy of a randomized, double-blind trial.

AIM: To determine the effect of the dipeptidyl peptidase-4 inhibitor linagliptin on postprandial glomerular hyperfiltration compared with the sulphonylurea glimepiride in adults with type 2 diabetes (T2D). MATERIALS AND METHODS: In this predefined substudy within a randomized, double-blind, parallel-group, intervention trial, overweight people with T2D without renal impairment were treated with once-daily linagliptin 5 mg (N = 10) or glimepiride 1 mg (N = 13) as an add-on to metformin for 8 weeks. After a standardized liquid protein-rich meal, the glomerular filtration rate (GFR) and effective renal plasma flow were determined by inulin and para-aminohippuric acid clearance, respectively, based on timed urine sampling. Intrarenal haemodynamics were estimated using the Gomez equations. Glucoregulatory/vasoactive hormones, urinary pH and fractional excretions (FE) of sodium, potassium and urea were measured. RESULTS: Compared with glimepiride, linagliptin increased the postprandial filtration fraction (FF; mean difference 2.1%-point; P = .016) and estimated glomerular hydraulic pressure (mean difference 3.0 mmHg; P = .050), and tended to increase GFR (P = .08) and estimated efferent renal arteriolar resistance (RE ; P = .08) from baseline to week 8. No differences in FE were noted. Glimepiride reduced HbA1c more than linagliptin (mean difference -0.40%; P = .004), without between-group differences in time-averaged postprandial glucose levels. In the linagliptin group, change in FF correlated with change in mean arterial pressure (R = 0.807; P = .009) and time-averaged mean glucagon (R = 0.782; P = .008), but not with changes in glucose, insulin, intact glucagon-like peptide-1, renin or FENa . Change in glucagon was associated with change in RE (R = 0.830; P = .003). CONCLUSIONS: In contrast to our hypothesis, compared with glimepiride, linagliptin does not reduce postprandial hyperfiltration, yet appears to increase FF after meal ingestion by increasing blood pressure or RE .

Kidney hemodynamic function in men and postmenopausal women with type 2 diabetes and preserved kidney function.

The progression of kidney disease may differ between sexes in type 2 diabetes (T2D), with previous studies reporting a slower decline in women. Glomerular hyperfiltration is a key factor driving the kidney function decline. The current study aimed to investigate the differences in kidney hemodynamic function between men and women with T2D. A cross-sectional analysis of pooled data from three studies compared kidney hemodynamic function between men and postmenopausal women with T2D without overt nephropathy. The outcome measures were glomerular filtration rate (GFR; inulin clearance), effective renal plasma flow (ERPF; p-aminohippurate clearance), filtration fraction (GFR/ERPF), and renal vascular resistance (RVR; mean arterial pressure/renal blood flow). Glomerular hydraulic pressure (PGLO) as well as afferent and efferent vascular resistance were estimated by Gomez formulae. Sex differences were assessed with linear regression models adjusted for systolic blood pressure, glucose, use of renin-angiotensin system blockers, and body mass index. In total, 101 men [age: 63 (58-68) yr, body mass index: 31.5 ± 3.9 kg/m2, GFR: 111 ± 18 mL/min, HbA1c: 7.4 ± 0.7%] and 27 women [age: 66 (62-69) yr, body mass index: 30.9 ± 4.5 kg/m2, GFR: 97 ± 11 mL/min, HbA1c: 7.1 ± 0.5%] were included. GFR was higher in men versus women [11.0 mL/min (95% confidence interval: 3.6, 18.4)]. Although statistically nonsignificant, PGLO trended higher in men [1.9 mmHg (95% confidence interval: -0.1, 4.0)], whereas RVR [-0.012 mmHg/L/min (95% confidence interval: -0.022, -0.002)] and afferent vascular resistance were lower [-361 dyn/s/cm5 (95% confidence interval: -801, 78)]. In conclusion, in adults without overt nephropathy, GFR was higher in men compared with women. PGLO also trended to be higher in men. Both findings are possibly related to afferent vasodilation and suggest greater prevalence of hyperfiltration. This could contribute to accelerated GFR loss over time in men with T2D.NEW & NOTEWORTHY In adults with type 2 diabetes, men had higher markers of hyperfiltration, which could potentially explain the accelerated progression of diabetic kidney disease in men compared with women.

Effects of a Hypercaloric and Hypocaloric Diet on Insulin-Induced Microvascular Recruitment, Glucose Uptake, and Lipolysis in Healthy Lean Men.

OBJECTIVE: In mice fed a high-fat diet, impairment of insulin signaling in endothelium is an early phenomenon that precedes decreased insulin sensitivity of skeletal muscle, adipose tissue, and liver. We assessed in humans whether short-term overfeeding affects insulin-induced microvascular recruitment in skeletal muscle and adipose tissue before changes occur in glucose uptake and lipolysis. Approach and Results: Fifteen healthy males underwent a hypercaloric and subsequent hypocaloric diet intervention. Before, during, and after the hypercaloric diet, and upon return to baseline weight, all participants underwent (1) a hyperinsulinemic-euglycemic clamp to determine insulin-induced glucose uptake and suppression of lipolysis (2) contrast-enhanced ultrasonography to measure insulin-induced microvascular recruitment in skeletal muscle and adipose tissue. In addition, we assessed insulin-induced vasodilation of isolated skeletal muscle resistance arteries by pressure myography after the hypercaloric diet in study participants and controls (n=5). The hypercaloric diet increased body weight (3.5 kg; P<0.001) and fat percentage (3.5%; P<0.001) but did not affect glucose uptake nor lipolysis. The hypercaloric diet increased adipose tissue microvascular recruitment (P=0.041) and decreased the ratio between skeletal muscle and adipose tissue microvascular blood volume during hyperinsulinemia (P=0.019). Insulin-induced vasodilation of isolated skeletal muscle arterioles was significantly lower in participants compared with controls (P<0.001). The hypocaloric diet reversed all of these changes, except the increase in adipose tissue microvascular recruitment. CONCLUSIONS: In lean men, short-term overfeeding reduces insulin-induced vasodilation of skeletal muscle resistance arteries and shifts the distribution of tissue perfusion during hyperinsulinemia from skeletal muscle to adipose tissue without affecting glucose uptake and lipolysis. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02628301.

DPARD: rationale, design and initial results from the Dutch national diabetes registry.

BACKGROUND: Treatment of diabetes mellitus has majorly improved over the past century, however, the disease burden is high and its prevalence still expanding. Further insight in the diabetes population is imperative to improve the quality of diabetes care by enhancement of knowledge-based diabetes management strategies. To this end, in 2017 a Dutch nationwide consortium of diabetologists, paediatric endocrinologists, and diabetes patients has founded a national outpatient diabetes care registry named Dutch Pediatric and Adult Registry of Diabetes (DPARD). We aim to describe the implementation of DPARD and to provide an overview of the characteristics of patients included during the first 2 years. METHODS: For the DPARD cohort with long-term follow-up of observational nature, hospital data are gathered directly from electronic health records and securely transferred and stored. DPARD provides weekly updated clinical information on the diabetes population care on a hospital-level benchmarked against the national average. RESULTS: Between November 2017 and January 2020, 20,857 patients were included from 8 (11%) Dutch hospitals with a level of care distribution representative of all diabetic outpatients in the Netherlands. Among patients with known diabetes type, 41% had type 1 diabetes, 51% type 2 diabetes, and 8% had diabetes due to other causes. Characteristics of the total patient population were similar to patients with unknown diabetes classification. HbA1c levels decreased over the years, while BMI levels showed an increase over time. CONCLUSIONS: The national DPARD registry aims to facilitate investigation of prevalence and long-term outcomes of Dutch outpatients with diabetes mellitus and their treatment, thus allowing for quality improvement of diabetes care as well as allowing for comparison of diabetes care on an international level.

The value of ambulatory blood pressure measurement to detect masked diastolic hypotension in older patients treated for hypertension.

OBJECTIVE: assess how many patients with low ambulatory diastolic blood pressure (DBP) are not identified when relying on office DBP alone, and thus have 'masked diastolic hypotension'. DESIGN: cross-sectional, retrospective cohort study. SETTING: academic hospital. SUBJECTS: 848 patients treated for hypertension who received ambulatory blood pressure monitoring (ABPM). METHODS: cut-off value between on- and off-target systolic blood pressure (SBP): 140 mmHg. Cut-off for low office and/or ambulatory DBP: DBP ≤ 70 mmHg. 'Masked diastolic hypotension' was defined as office DBP > 70 mmHg and mean ambulatory DBP ≤ 70 mmHg. RESULTS: mean age of the sample was 60 ± 13 years, 50% was female, 37% had diabetes, 42% preexisting cardiovascular disease (CVD), mean office blood pressure (BP) was 134/79 mmHg. In all patients (n = 848), low office DBP was present in n = 84(10%), while n = 183(22%) had low ambulatory DBP. In all patients with normal-to-high office DBP (n = 764), n = 122(16%) had 'masked diastolic hypotension'. In this group, ambulatory DBP was 14-19 mmHg lower than office DBP. Patients with low ambulatory DBP were older, had more (cardiovascular) comorbidities, and used more (antihypertensive) drugs. Antihypertensive drugs were lowered or discontinued in 30% of all patients with 'masked diastolic hypotension' due to side effects. CONCLUSIONS: 'masked diastolic hypotension' is common among patients treated for hypertension, particularly in older patients with CVD (e.g. coronary artery disease, diabetes), patient groups in which the European Society of Cardiology/Hypertension guideline advises to prevent low DBP. Although it remains to be examined at which BP levels the harms of low DBP outweigh the benefits of lowering SBP, our observations are aimed to increase awareness among physicians.

The renal hemodynamic effects of the SGLT2 inhibitor dapagliflozin are caused by post-glomerular vasodilatation rather than pre-glomerular vasoconstriction in metformin-treated patients with type 2 diabetes in the randomized, double-blind RED trial.

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) improve hard renal outcomes in type 2 diabetes. This is possibly explained by the fact that SGLT2i normalize the measured glomerular filtration rate (mGFR) by increasing renal vascular resistance, as was shown in young people with type 1 diabetes and glomerular hyperfiltration. Therefore, we compared the renal hemodynamic effects of dapagliflozin with gliclazide in type 2 diabetes. The mGFR and effective renal plasma flow were assessed using inulin and para-aminohippurate clearances in the fasted state, during clamped euglycemia (5 mmol/L) and during clamped hyperglycemia (15 mmol/L). Filtration fraction and renal vascular resistance were calculated. Additionally, factors known to modulate renal hemodynamics were measured. In 44 people with type 2 diabetes on metformin monotherapy (Hemoglobin A1c 7.4%, mGFR 113 mL/min), dapagliflozin versus gliclazide reduced mGFR by 5, 10, and 12 mL/min in the consecutive phases while both agents similarly improved Hemoglobin A1c (-0.48% vs -0.65%). Dapagliflozin also reduced filtration fraction without increasing renal vascular resistance, and increased urinary adenosine and prostaglandin concentrations. Gliclazide did not consistently alter renal hemodynamic parameters. Thus, beyond glucose control, SGLT2i reduce mGFR and filtration fraction in type 2 diabetes. The fact that renal vascular resistance was not increased by dapagliflozin suggests that this is due to post-glomerular vasodilation rather than pre-glomerular vasoconstriction.

SGLT2 inhibition versus sulfonylurea treatment effects on electrolyte and acid-base balance: secondary analysis of a clinical trial reaching glycemic equipoise: Tubular effects of SGLT2 inhibition in Type 2 diabetes.

Sodium-glucose transporter (SGLT)2 inhibitors increase plasma magnesium and plasma phosphate and may cause ketoacidosis, but the contribution of improved glycemic control to these observations as well as effects on other electrolytes and acid-base parameters remain unknown. Therefore, our objective was to compare the effects of SGLT2 inhibitors dapagliflozin and sulfonylurea gliclazide on plasma electrolytes, urinary electrolyte excretion, and acid-base balance in people with Type 2 diabetes (T2D). We assessed the effects of dapagliflozin and gliclazide treatment on plasma electrolytes and bicarbonate, 24-hour urinary pH and excretions of electrolytes, ammonium, citrate, and sulfate in 44 metformin-treated people with T2D and preserved kidney function. Compared with gliclazide, dapagliflozin increased plasma chloride by 1.4 mmol/l (95% CI 0.4-2.4), plasma magnesium by 0.03 mmol/l (95% CI 0.01-0.06), and plasma sulfate by 0.02 mmol/l (95% CI 0.01-0.04). Compared with baseline, dapagliflozin also significantly increased plasma phosphate, but the same trend was observed with gliclazide. From baseline to week 12, dapagliflozin increased the urinary excretion of citrate by 0.93 ± 1.72 mmol/day, acetoacetate by 48 µmol/day (IQR 17-138), and ß-hydroxybutyrate by 59 µmol/day (IQR 0-336), without disturbing acid-base balance. In conclusion, dapagliflozin increases plasma magnesium, chloride, and sulfate compared with gliclazide, while reaching similar glucose-lowering in people with T2D. Dapagliflozin also increases urinary ketone excretion without changing acid-base balance. Therefore, the increase in urinary citrate excretion by dapagliflozin may reflect an effect on cellular metabolism including the tricarboxylic acid cycle. This potentially contributes to kidney protection.

Effects of dipeptidyl peptidase-4 inhibitor linagliptin versus sulphonylurea glimepiride on systemic haemodynamics in overweight patients with type 2 diabetes: A secondary analysis of an 8-week, randomized, controlled, double-blind trial.

AIM: To determine the glucose-independent effect of the dipeptidyl peptidase-4 (DPP-4) inhibitor linagliptin versus the sulphonylurea glimepiride on systemic haemodynamics in the fasting and postprandial state in patients with type 2 diabetes (T2D). MATERIALS AND METHODS: In this prespecified secondary analysis of a phase IV, double-blind trial, 46 metformin-treated, overweight patients with T2D were included and randomly assigned (1:1) to once-daily linagliptin (5 mg) or glimepiride (1 mg) for 8 weeks. In a sub-study involving 26 patients, systemic haemodynamics were also assessed following a standardized liquid meal (Nutridrink Yoghurt style). Systemic haemodynamics (oscillometric device and finger photoplethysmography), arterial stiffness (applanation tonometry) and cardiac sympathovagal balance (heart rate variability [HRV]) were measured in the fasting state and repetitively following the meal. Ewing tests were performed in the fasting state. RESULTS: From baseline to week 8, linagliptin compared with glimepiride did not affect systemic haemodynamics, arterial stiffness or HRV in the fasting state. Linagliptin increased parasympathetic nervous activity, as measured by the Valsalva manoeuvre (P = .021) and deep breathing test (P = .027) compared with glimepiride. Postprandially, systolic blood pressure (SBP) dropped an average of 7.6 ± 1.6 mmHg. Linagliptin reduced this decrease to 0.7 ± 2.3 mmHg, which was significant to glimepiride (P = .010). CONCLUSIONS: When compared with glimepiride, linagliptin does not affect fasting blood pressure. However, linagliptin blunted the postprandial drop in SBP, which could benefit patients with postprandial hypotension.

Renal sinus fat and renal hemodynamics: a cross-sectional analysis.

OBJECTIVES: Increased renal sinus fat (RSF) is associated with hypertension and chronic kidney disease, but underlying mechanisms are incompletely understood. We evaluated relations between RSF and gold-standard measures of renal hemodynamics in type 2 diabetes (T2D) patients. METHODS: Fifty-one T2D patients [age 63 ± 7 years; BMI 31 (28-34) kg/m2; GFR 83 ± 16 mL/min/1.73 m2] underwent MRI-scanning to quantify RSF volume, and subcutaneous and visceral adipose tissue compartments (SAT and VAT, respectively). GFR and effective renal plasma flow (ERPF) were determined by inulin and PAH clearances, respectively. Effective renal vascular resistance (ERVR) was calculated. RESULTS: RSF correlated negatively with GFR (r = - 0.38; p = 0.006) and ERPF (r = - 0.38; p = 0.006) and positively with mean arterial pressure (MAP) (r = 0.29; p = 0.039) and ERVR (r = 0.45, p = 0.001), which persisted after adjustment for VAT, MAP, sex, and BMI. After correction for age, ERVR remained significantly related to RSF. CONCLUSIONS: In T2D patients, higher RSF volume was negatively associated to GFR. In addition, RSF volume was positively associated with increased renal vascular resistance, which may mediate hypertension and CKD development. Further research is needed to investigate how RSF may alter the (afferent) vascular resistance of the renal vasculature.

Renal tubular effects of prolonged therapy with the GLP-1 receptor agonist lixisenatide in patients with type 2 diabetes mellitus.

Glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) are well-established glucose-lowering drugs for type 2 diabetes mellitus (T2DM) management. Acute GLP-1RA administration increases urinary excretion of sodium and other electrolytes. However, the renal tubular effects of prolonged GLP-1RA treatment are largely unknown. In this secondary analysis of a randomized trial, we determined the renal tubular effects of 8-wk treatment with 20 µg lixisenatide, a short-acting (prandial) GLP-1RA, versus titrated once-daily insulin glulisine in 35 overweight T2DM-patients on stable insulin glargine background therapy (age: 62 ± 7 yr, glycated hemoglobin: 8.0 ± 0.9%, estimated glomerular filtration rate: >60 ml·min-1·1.73 m-2). After a standardized breakfast, lixisenatide increased absolute and fractional excretions of sodium, chloride, and potassium and increased urinary pH. In contrast, lixisenatide reduced absolute and fractional excretions of magnesium, calcium, and phosphate. At week 8, patients treated with lixisenatide had significantly more phosphorylated sodium-hydrogen exchanger isoform 3 (NHE3) in urinary extracellular vesicles than those on insulin glulisine treatment, which suggested decreased NHE3 activity in the proximal tubule. A rise in postprandial blood pressure with lixisenatide partly explained the changes in the urinary excretion of sodium, potassium, magnesium, and phosphate and the changes in urinary pH. In conclusion, lixisenatide affects postprandial urinary excretion of several electrolytes and increases urinary pH compared with insulin glulisine in T2DM patients after 8 wk of treatment. This is most likely explained by a drug-induced rise in blood pressure or direct inhibitory effects on NHE3 in the proximal tubule.

Metabolite ratios as potential biomarkers for type 2 diabetes: a DIRECT study.

AIMS/HYPOTHESIS: Circulating metabolites have been shown to reflect metabolic changes during the development of type 2 diabetes. In this study we examined the association of metabolite levels and pairwise metabolite ratios with insulin responses after glucose, glucagon-like peptide-1 (GLP-1) and arginine stimulation. We then investigated if the identified metabolite ratios were associated with measures of OGTT-derived beta cell function and with prevalent and incident type 2 diabetes. METHODS: We measured the levels of 188 metabolites in plasma samples from 130 healthy members of twin families (from the Netherlands Twin Register) at five time points during a modified 3 h hyperglycaemic clamp with glucose, GLP-1 and arginine stimulation. We validated our results in cohorts with OGTT data (n = 340) and epidemiological case-control studies of prevalent (n = 4925) and incident (n = 4277) diabetes. The data were analysed using regression models with adjustment for potential confounders. RESULTS: There were dynamic changes in metabolite levels in response to the different secretagogues. Furthermore, several fasting pairwise metabolite ratios were associated with one or multiple clamp-derived measures of insulin secretion (all p < 9.2 × 10-7). These associations were significantly stronger compared with the individual metabolite components. One of the ratios, valine to phosphatidylcholine acyl-alkyl C32:2 (PC ae C32:2), in addition showed a directionally consistent positive association with OGTT-derived measures of insulin secretion and resistance (p ≤ 5.4 × 10-3) and prevalent type 2 diabetes (ORVal_PC ae C32:2 2.64 [ß 0.97 ± 0.09], p = 1.0 × 10-27). Furthermore, Val_PC ae C32:2 predicted incident diabetes independent of established risk factors in two epidemiological cohort studies (HRVal_PC ae C32:2 1.57 [ß 0.45 ± 0.06]; p = 1.3 × 10-15), leading to modest improvements in the receiver operating characteristics when added to a model containing a set of established risk factors in both cohorts (increases from 0.780 to 0.801 and from 0.862 to 0.865 respectively, when added to the model containing traditional risk factors + glucose). CONCLUSIONS/INTERPRETATION: In this study we have shown that the Val_PC ae C32:2 metabolite ratio is associated with an increased risk of type 2 diabetes and measures of insulin secretion and resistance. The observed effects were stronger than that of the individual metabolites and independent of known risk factors.

The 'morning dip' in antimicrobial appropriateness: circumstances determining appropriateness of antimicrobial prescribing.

Objectives: Quality of care has been shown to vary depending on the time of day or day of the week and depending on caregivers' gender and experience. We aimed to study how these factors influence quality of antimicrobial prescribing. Methods: Prospective point-prevalence surveys were performed to determine the association between the above-mentioned prescription factors and antimicrobial appropriateness. Surveys included cases of patients admitted to a tertiary care hospital with a prescribed systemic antimicrobial drug and its prescribers. The main outcome was appropriateness of antimicrobial prescriptions. A post hoc qualitative survey among hospital physicians asked physicians to reflect on the results. Results: The study included 351 antimicrobial prescriptions by 150 physicians prescribed for 276 patients. Appropriateness of antimicrobial prescribing in the morning was significantly lower compared with the afternoon and evening/night [43% versus 68% versus 70%, crude OR afternoon versus morning = 3.00 (95% CI = 1.60-5.48), crude OR evening/night versus morning = 3.40 (95% CI = 1.64-6.69)]. First-year residents performed significantly worse than their more experienced colleagues [51% versus 69%, crude OR = 2.09 (95% CI = 1.26-3.38)]. Infectious disease expert consultation improved appropriateness [54% versus 81%, crude OR = 3.71 (95% CI = 2.05-6.23)]. No significant effects for gender or office hours versus non-office hours were found. Post hoc survey results suggest creating room to improve prescribing circumstances during mornings and for inexperienced physicians. Conclusions: Antimicrobial prescribing was less appropriate in the mornings and when prescribed by inexperienced physicians. Appropriateness may be increased by improving prescribing circumstances.

Improving antibiotic prescribing skills in medical students: the effect of e-learning after 6 months.

Background: Antimicrobial prescribing behaviour is first established during medical study, but teachers often cite lack of time as an important problem in the implementation of antimicrobial stewardship in the medical curriculum. The use of electronic learning (e-learning) is a potentially time-efficient solution, but its effectiveness in changing long-term prescribing behaviour in medical students is as yet unknown. Methods: We performed a prospective controlled intervention study of the long-term effects of a short interactive e-learning course among fourth year medical students in a Dutch university. The e-learning was temporarily implemented as a non-compulsory course during a 6 week period. Six months later, all students underwent an infectious disease-based objective structured clinical examination (OSCE) aimed at simulating postgraduate prescribing. If they passed, each student did the OSCE only once. We created a control group of students from a period when the e-learning was not implemented. Main outcomes were the OSCE pass percentage and knowledge, drug choice and overall scores. We used propensity scores to create equal comparisons. Results: We included 71 students in the intervention group and 285 students in the control group. E-learning participation in the intervention group was 81%. The OSCE pass percentage was 86% in the control group versus 97% in the intervention group (+11%, OR 5.9, 95% CI 1.7-20.0). OSCE overall, knowledge and drug choice grades (1-10) were also significantly higher in the intervention group (differences +0.31, +0.31 and +0.51, respectively). Conclusions: E-learning during a limited period can significantly improve medical students' performance of an antimicrobial therapeutic consultation in a situation simulating clinical practice 6 months later.

Effect of immediate and prolonged GLP-1 receptor agonist administration on uric acid and kidney clearance: Post-hoc analyses of four clinical trials.

AIMS: To determine the effects of glucagon-like peptide (GLP)-1 receptor agonists (RA) on uric acid (UA) levels and kidney UA clearance. MATERIAL AND METHODS: This study involved post-hoc analyses of 4 controlled clinical trials, which assessed actions of GLP-1RA administration on kidney physiology. The immediate effects of GLP-1RA exenatide infusion vs placebo were determined in 9 healthy overweight men (Study-A) and in 52 overweight T2DM patients (Study-B). The effects of 12 weeks of long-acting GLP-1RA liraglutide vs placebo in 36 overweight T2DM patients (Study-C) and of 8 weeks of short-acting GLP-1RA lixisenatide vs once-daily titrated insulin glulisine in 35 overweight T2DM patients (Study-D) were also examined. Plasma UA, fractional (inulin-corrected) and absolute urinary excretion of UA (UEUA ) and sodium (UENa ), and urine pH were determined. RESULTS: Median baseline plasma UA level was 5.39 to 6.33 mg/dL across all studies (17%-22% of subjects were hyperuricaemic). In Study-A, exenatide infusion slightly increased plasma UA (+0.07 ± 0.02 mg/dL, P = .04), and raised absolute-UEUA (+1.58 ± 0.65 mg/min/1.73 m2 , P = .02), but did not affect fractional UEUA compared to placebo. Fractional UEUA and absolute UEUA correlated with increases in urine pH (r:0.86, P = .003 and r:0.92, P < .001, respectively). Fractional UEUA correlated with increased fractional UENa (r:0.76, P = .02). In Study-B, exenatide infusion did not affect plasma UA, but increased fractional UEUA (+0.76 ± 0.38%, P = .049) and absolute UEUA (+0.75 ± 0.27 mg/min/1.73 m2 , P = .007), compared to placebo. In regression analyses, both parameters were explained by changes in urine pH and, in part, by changes in UENa . In Study-C, liraglutide treatment did not affect plasma UA, UEUA, UENa or urine pH, compared to placebo. In Study-D, lixisenatide treatment increased UENa and urine pH from baseline, but did not affect plasma UA or UEUA . CONCLUSION: Immediate exenatide infusion increases UEUA in overweight healthy men and in T2DM patients, probably by inhibiting Na+ /H+ -exchanger type-3 in the renal proximal tubule. Prolonged treatment with a long-acting or short-acting GLP-1RA does not affect plasma UA or UEUA in T2DM patients with normal plasma UA levels and at relatively low cardiovascular risk. Our results suggest that the cardio-renal benefits of GLP-1RA are not mediated through changes in UA.

Iloprost infusion prevents the insulin-induced reduction in skeletal muscle microvascular blood volume but does not enhance peripheral glucose uptake in type 2 diabetic patients.

AIMS: In type 2 diabetes impaired insulin-induced muscle perfusion is thought to contribute to reduced whole-body glucose uptake. In this study, we examined the effects of iloprost, a stable prostacyclin analogue, on insulin-induced muscle capillary recruitment and whole-body glucose uptake. MATERIALS AND METHODS: In a randomized cross-over design, 12 type 2 diabetes patients (age, 55 [46-69] years; BMI, 33.1 [31.0-39] kg/m2 ) underwent two hyperinsulinaemic-euglycaemic clamps, one with and one without simultaneous low-dose iloprost infusion. Contrast-enhanced ultrasonography of the vastus lateralis muscle was performed before and during the clamp. Muscle capillary recruitment was calculated as percentage change in microvascular blood volume (MBV) before and during the clamp. RESULTS: Insulin infusion reduced skeletal muscle MBV by ~50% compared to the fasting state (fasting, 1.77·10-4 [1.54·10-5 -2.44·10-3 ] arbitrary units (AU); hyperinsulinaemia, 6.69·10-5 [2.68·10-6 -5.72·10-4 ] AU; P = 0.050). Infusion of iloprost prevented this insulin-induced skeletal muscle capillary derecruitment, from (-49.5 [-89.5 to 55.3] %) to (8.0 [-68.8 to 306.6] %), for conditions without and with iloprost, respectively. The rate of glucose disappearance (Rd ) did not change significantly during iloprost infusion (17.3 [10.0-40.8] µmol/kg/min) compared with insulin infusion alone (17.6 [9.9-68.7] µmol/kg/min). CONCLUSIONS: Our data suggest that acute improvement in insulin-stimulated muscle perfusion is not an attractive therapeutic approach to bypass cellular resistance to glucose uptake in type 2 diabetes. Whether long-term improvements in insulin-induced muscle perfusion may prove beneficial for glucose disposal remains to be determined.

Haloperidol versus placebo for delirium prevention in acutely hospitalised older at risk patients: a multi-centre double-blind randomised controlled clinical trial.

Background: because the few randomised placebo-controlled trials investigating the potential role for prophylactic haloperidol in delirium prevention have focused on specific surgical populations, we investigated its efficacy and safety in acutely hospitalised older patients. Methods: this multi-centre, double-blind, stratified, block randomised, placebo-controlled trial was conducted at six Dutch hospitals. Patients age ≥70 years, acutely admitted through the emergency department for general medicine or surgical specialties and at risk for delirium were randomised (n = 245) to haloperidol or placebo 1 mg orally twice-daily (maximum of 14 doses) on top of standard nonpharmacological prevention strategies. The primary outcome was delirium incidence. Other endpoints included delirium severity and duration, drug safety and clinical outcomes. Results: intention-to-treat analysis included 242 participants (calculated sample size n = 390, statistical power of current sample 59%) allocated to haloperidol (n = 118) or placebo (n = 124). In the haloperidol and placebo group, delirium incidence was 19.5 versus 14.5% (OR 1.43, 95% CI 0.72 to 2.78); median (IQR) delirium duration 4 (2, 5) versus 3 (1, 6) days (P = 0.366); maximum DRS-R-98 score 16 (9.8, 19.5) versus 10 (5.5, 22.5) (P = 0.549; 53.7% missing data); hospital LOS 7 (4, 10.3) versus 7 (5, 11.8) days (P = 0.343); 3-month mortality 9.9 versus 12.5% (OR 0.77, 95% CI 0.34 to 1.75), respectively. No treatment-limiting side effects were noted. Conclusions: prophylactic low-dose oral haloperidol did not reduce delirium incidence in acutely hospitalised older patients. Therefore, prophylactic use of haloperidol in this population is not recommended.

Effects of exenatide on cardiac function, perfusion, and energetics in type 2 diabetic patients with cardiomyopathy: a randomized controlled trial against insulin glargine.

BACKGROUND: Multiple bloodglucose-lowering agents have been linked to cardiovascular events. Preliminary studies showed improvement in left ventricular (LV) function during glucagon-like peptide-1 receptor agonist administration. Underlying mechanisms, however, are unclear. The purpose of this study was to investigate myocardial perfusion and oxidative metabolism in type 2 diabetic (T2DM) patients with LV systolic dysfunction as compared to healthy controls. Furthermore, effects of 26-weeks of exenatide versus insulin glargine administration on cardiac function, perfusion and oxidative metabolism in T2DM patients with LV dysfunction were explored. METHODS AND RESULTS: Twenty-six T2DM patients with LV systolic dysfunction (cardiac magnetic resonance (CMR) derived LV ejection fraction (LVEF) of 47 ± 13%) and 10 controls (LVEF of 59 ± 4%, P < 0.01 as compared to patients) were analyzed. Both myocardial perfusion during adenosine-induced hyperemia (P < 0.01), and coronary flow reserve (P < 0.01), measured by [15O]H2O positron emission tomography (PET), were impaired in T2DM patients as compared to healthy controls. Myocardial oxygen consumption and myocardial efficiency, measured using [11C]acetate PET and CMR derived stroke volume, were not different between the groups. Eleven patients in the exenatide group and 12 patients in the insulin glargine group completed the trial. Systemic metabolic control was improved after both treatments, although, no changes in cardiac function, perfusion and metabolism were seen after exenatide or insulin glargine. CONCLUSIONS: T2DM patients with LV systolic dysfunction did not have altered myocardial efficiency as compared to healthy controls. Exenatide or insulin glargine had no effects on cardiac function, perfusion or oxidative metabolism. Trial registration NCT00766857.

Postprandial renal haemodynamic effect of lixisenatide vs once-daily insulin-glulisine in patients with type 2 diabetes on insulin-glargine: An 8-week, randomised, open-label trial.

AIM: To determine whether lixisenatide, a prandial short-acting glucagon-like peptide receptor agonist (GLP-1RA), ameliorates postprandial glomerular hyperfiltration in patients with type 2 diabetes mellitus (T2DM) compared with insulin-glulisine (iGlu). METHODS: Postprandial renal haemodynamic effects of 8-week treatment with lixisenatide 20 µg vs once-daily titrated iGlu were measured in 35 overweight patients with T2DM inadequately controlled on insulin-glargine, with or without metformin [mean ± SD age 62 ± 7 years, HbA1c 8.0% ± 0.9%, estimated glomerular filtration rate (GFR) 85 ± 12 mL/min/1.73 m2 , median (IQR) urinary albumin/creatinine ratio 1.5 (0.9-3.0) mg/mmol]. After a standardised breakfast, GFR (primary endpoint) and effective renal plasma flow (ERPF) were determined by inulin and para-aminohippuric acid renal clearance, respectively, based on timed urine sampling. Intrarenal haemodynamic functions were estimated using Gomez equations. RESULTS: Compared with iGlu, lixisenatide did not affect GFR [+0.1 mL/min/1.73 m2 (95% CI -9 to 9)], ERPF [-17 mL/min/1.73 m2 (-61 to 26)], other (intra-)renal haemodynamics or renal damage markers, but increased fractional sodium excretion [+0.25% (0.09-0.41)] and urinary pH [+0.7 (0.3-1.2)]. Plasma renin, angiotensin-II and aldosterone were unchanged. Lixisenatide and iGlu reduced HbA1c similarly, by 0.8% ± 0.1% and 0.6% ± 0.1%, respectively, while postprandial glucose was lower with lixisenatide (P = .002). Compared with iGlu, lixisenatide reduced bodyweight [-1.4 kg (-2.5 to -0.2)] and increased postprandial mean arterial pressure [+9 mm Hg (4-14)]. CONCLUSION: Eight-week lixisenatide treatment does not affect postprandial (intra-)renal haemodynamics compared with iGlu when added to insulin-glargine in patients with T2DM without overt nephropathy. Prolonged lixisenatide treatment has a sustained natriuretic effect, which is in contrast to previous reports on long-acting GLP-1RA, reduces body weight and increases postprandial blood pressure compared with iGlu. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02276196.