Effect of ovarian suppression with gonadotropin-releasing hormone agonist on glucose disposal and insulin secretion

Several lines of evidence suggest that ovarian hormones influence glucose homeostasis, although their exact role in humans has not been clearly defined. In the present study, we sought to test the hypothesis that ovarian hormones regulate glucose homeostasis by examining the effect of pharmacologically induced ovarian hormone deficiency on glucose disposal and insulin secretion. Young, healthy women with regular menstrual patterns were studied during the follicular and luteal phases of their cycle at baseline and after 2 mo of treatment with gonadotropin-releasing hormone agonist (GnRHa; n = 7) or placebo (n = 6). Using hyperglycemic clamps, in combination with stable isotope-labeled (i.e., (13)C and (2)H) glucose tracers, we measured glucose disposal and insulin secretion. Additionally, we assessed body composition and regional fat distribution using radiologic imaging techniques as well as glucoregulatory hormones. Ovarian hormone suppression with GnRHa did not alter body composition, abdominal fat distribution, or thigh tissue composition. There was no effect of ovarian suppression on total, oxidative, or nonoxidative glucose disposal expressed relative to plasma insulin level. Similarly, no effect of ovarian hormone deficiency was observed on first- or second-phase insulin secretion or insulin clearance. Finally, ovarian hormone deficiency was associated with an increase in circulating adiponectin levels but no change in leptin concentration. Our findings suggest that a brief period of ovarian hormone deficiency in young, healthy, eugonadal women does not alter glucose disposal index or insulin secretion, supporting the conclusion that ovarian hormones play a minimal role in regulating glucose homeostasis. Our data do, however, support a role for ovarian hormones in the regulation of plasma adiponectin levels

Insulin resistance and insulin secretory dysfunction are independent predictors of worsening of glucose tolerance during each stage of type 2 diabetes development

WSTĘP. Chociaż wyniki prospektywnych prac wskazują, że zaburzenia działania i wydzielania insuliny zapowiadają wystąpienie cukrzycy typu 2, jednakże nie dostarczają one dostatecznych informacji o współudziale tych dwóch czynników w pogarszaniu tolerancji glukozy w różnych okresach rozwoju cukrzycy typu 2. Dlatego autorzy podjęli próbę niezależnej oceny wpływu zaburzeń wydzielania i działania insuliny na przejście od stanu prawidłowej tolerancji glukozy (NGT, normal glucose tolerance) do tolerancji nieprawidłowej (IGT, impaired glucose tolerance) i ze stanu IGT w cukrzycę. MATERIAŁ I METODY. U 254 Indian Pima z NGT i u 145 z IGT autorzy badali stymulowane insuliną usuwanie glukozy (M) (klamra hiperinsulinowa), wielkość wydzielania insuliny w fazie wczesnej (AIR, acute insulin secretory response) (25-gramowy dożylny test tolerancji glukozy) i zawartość składników ciała (hydrodensytometria lub ilościowa radiografia cyfrowa). Czas obserwacji tych osób wynosił 0,5&#8211;13 lat. WYNIKI. Po okresie obserwacji 4,4 &plusmn; 3,1 i 5,5 &plusmn; 3,4 lat u 79 (31%) osób, u których początkowo występowała NGT, rozwinęła się IGT, a u 64 (44%) osób z początkową IGT rozwinęła się cukrzyca. Analiza statystyczna przeprowadzona z uwzględnieniem wieku, płci i zawartości procentowej tłuszczu wskazała na niskie M i niskie AIR jako niezależne czynniki określające ryzyko przejścia od NGT do IGT (względne ryzyko [95% CI] dla 10. vs 90. percentyla: M 2,4 [1,2&#8211;4,7], p < 0,02; AIR 2,1 [1,1&#8211;4,1], p < 0,04), a dla przejścia IGT w cukrzycę (M 2,5 [1,3&#8211;5,0], p < 0,01; AIR 1,8 [0,99&#8211;3,3], p = 0,055). WNIOSKI. Zarówno zaburzenia w działaniu, jak i upośledzenie wydzielania insuliny są niezależnymi czynnikami zapowiadającymi pogorszenie tolerancji glukozy na każdym etapie rozwoju cukrzycy i oba powinny stanowić cel prewencji pierwotnej cukrzycy typu 2.OBJECTIVE. Although prospective studies indicate that insulin resistance and insulin secretory dysfunction predict type 2 diabetes, they provide limited information on the relative contributions of both abnormalities to worsening glucose tolerance at different developmental stages of the disease. We therefore assessed the predictive effect of insulin resistance and insulin secretory dysfunction separately for the progression from normal glucose tolerance (NGT) to impaired glucose tolerance (IGT) and from IGT to diabetes. RESEARCH DESIGN AND METHODS. Insulin-stimulated glucose disposal (M) (hyperinsulinemic clamp), acute insulin secretory response (AIR) (25-g intravenous glucose tolerance test), and body composition (hydrodensitometry or dual-energy X-ray absorptiometry) were measured in 254 Pima Indians with NGT and in 145 Pima Indians with IGT, who were then followed for 0.5&#150;13 years. RESULTS. After follow-ups of 4.4 &#177; 3.1 and 5.5 &#177; 3.4 years, 79 (31%) of the subjects with initial NGT had developed IGT, and 64 (44%) of the subjects with initial IGT had developed diabetes. In proportional-hazards analyses with adjustment for age, sex, and percent body fat, low M and low AIR were independent predictors of both the progression from NGT to IGT (relative hazards [95% CI] for 10th vs. 90th percentile: M2.4 [1.2&#150;4.7], P < 0.02; AIR 2.1 [1.1&#150;4.1], P < 0.04) and from IGT to diabetes (M2.5 [1.3&#150;5.0], P < 0.01; AIR 1.8 [0.99&#150;3.3], P = 0.055). CONCLUSIONS. During each stage of the development of type 2 diabetes, insulin resistance and insulin secretory dysfunction are independent predictors of worsening glucose tolerance and are, therefore, both targets for the primary prevention of the disease

Pancreas-enriched miRNAs are altered in the circulation of subjects with diabetes: a pilot cross-sectional study

The clinical presentation of diabetes sometimes overlaps, contributing to ambiguity in the diagnosis. Thus, circulating pancreatic islet-enriched microRNAs (miRNAs) might be useful biomarkers of β-cell injury/dysfunction that would allow more accurate subtyping of diabetes. We measured plasma levels of selected miRNAs in subjects with prediabetes (n = 12), type 2 diabetes (T2D, n = 31), latent autoimmune diabetes of adults (LADA, n = 6) and type 1 diabetes (T1D, n = 16) and compared them to levels in healthy control subjects (n = 27). The study was conducted at the Translational Research Institute for Metabolism and Diabetes (TRI-MD), Florida Hospital. MiRNAs including miR-375 (linked to β-cell injury), miR-21 (associated with islet inflammation), miR-24.1, miR-30d, miR-34a, miR-126, miR-146, and miR-148a were significantly elevated in subjects with various forms of diabetes compared to healthy controls. Levels of several miRNAs were significantly correlated with glucose responses during oral glucose tolerance testing, HbA[subscript 1c], β-cell function, and insulin resistance in healthy controls, prediabetes, and T2D. These data suggest that miRNAs linked to β-cell injury and islet inflammation might be useful biomarkers to distinguish between subtypes of diabetes. This information could be used to predict progression of the disease, guide selection of optimal therapy and monitor responses to interventions, thus improving outcomes in patients with diabetes.Translational Research Institute for Metabolism and Diabetes (TRI

Cardiovascular and renal outcomes by baseline albuminuria status and renal function — results from the LEADER randomized trial

Aim: To assess cardiorenal outcomes by baseline urinary albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) in the contemporary LEADER cohort. Materials and methods: LEADER was a multinational, double-blind trial. Patients with type 2 diabetes and high cardiovascular (CV) risk were randomized 1:1 to the glucagon-like peptide-1 analogue liraglutide (≤1.8 mg daily; n = 4668) or placebo (n = 4672) plus standard care and followed for 3.5 to 5 years. Primary composite outcomes were time to first non-fatal myocardial infarction, non-fatal stroke or CV death. Post hoc Cox regression analyses of outcomes by baseline UACR and eGFR subgroups were conducted with adjustment for baseline variables. Results: In the LEADER population, 1598 (17.5%), 2917 (31.9%), 1200 (13.1%), 1611 (17.6%), 845 (9.2%) and 966 (10.6%) had UACR = 0, >0 to <15, 15 to <30, 30 to <100, 100 to <300 and ≥300 mg/g, respectively. Increasing UACR and decreasing eGFR were linked with higher risks of the primary outcome, heart failure hospitalization, a composite renal outcome and death (P-values for the Cochran-Armitage test for trends were all <.0001). Across UACR and eGFR subgroups, risks of cardiorenal events and death were generally lower or similar with liraglutide versus placebo. Conclusions: In a contemporary type 2 diabetes population, increasing baseline UACR and declining eGFR were linked with higher risks of cardiorenal events and death

Changes in Albuminuria Predict Cardiovascular and Renal Outcomes in Type 2 Diabetes: A Post Hoc Analysis of the LEADER Trial

OBJECTIVE A post hoc analysis to investigate the association between 1-year changes in albuminuria and subsequent risk of cardiovascular and renal events. RESEARCH DESIGN AND METHODS LEADER was a randomized trial of liraglutide up to 1.8 mg/day versus placebo added to standard care for 3.5-5 years in 9,340 participants with type 2 diabetes and high cardiovascular risk. We calculated change in urinary albumin-to-creatinine ratio (UACR) from baseline to 1 year in participants with >30% reduction (n = 2,928), 30-0% reduction (n = 1,218), or any increase in UACR (n = 4,124), irrespective of treatment. Using Cox regression, risks of major adverse cardiovascular events (MACE) and a composite nephropathy outcome (from 1 year to end of trial in subgroups by baseline UACR [= 300 mg/g]) were assessed. The analysis was adjusted for treatment allocation alone as a fixed factor and for baseline variables associated with cardiovascular and renal outcomes. RESULTS For MACE, hazard ratios (HRs) for those with >30% and 30-0% UACR reduction were 0.82 (95% CI 0.71, 0.94; P = 0.006) and 0.99 (0.82, 1.19; P = 0.912), respectively, compared with any increase in UACR (reference). For the composite nephropathy outcome, respective HRs were 0.67 (0.49, 0.93; P = 0.02) and 0.97 (0.66, 1.43; P = 0.881). Results were independent of baseline UACR and consistent in both treatment groups. After adjustment, HRs were significant and consistent in >30% reduction subgroups with baseline micro- or macroalbuminuria. CONCLUSIONS A reduction in albuminuria during the 1st year was associated with fewer cardiovascular and renal outcomes, independent of treatment. Albuminuria monitoring remains an important part of diabetes care, with great unused potential

Day-to-day fasting glycaemic variability in DEVOTE: associations with severe hypoglycaemia and cardiovascular outcomes (DEVOTE 2)

AIMS/HYPOTHESIS: The Trial Comparing Cardiovascular Safety of Insulin Degludec vs Insulin Glargine in Patients with Type 2 Diabetes at High Risk of Cardiovascular Events (DEVOTE) was a double-blind, randomised, event-driven, treat-to-target prospective trial comparing the cardiovascular safety of insulin degludec with that of insulin glargine U100 (100 units/ml) in patients with type 2 diabetes at high risk of cardiovascular events. This paper reports a secondary analysis investigating associations of day-to-day fasting glycaemic variability (pre-breakfast self-measured blood glucose [SMBG]) with severe hypoglycaemia and cardiovascular outcomes. METHODS: In DEVOTE, patients with type 2 diabetes were randomised to receive insulin degludec or insulin glargine U100 once daily. The primary outcome was the first occurrence of an adjudicated major adverse cardiovascular event (MACE). Adjudicated severe hypoglycaemia was the pre-specified secondary outcome. In this article, day-to-day fasting glycaemic variability was based on the standard deviation of the pre-breakfast SMBG measurements. The variability measure was calculated as follows. Each month, only the three pre-breakfast SMBG measurements recorded before contact with the site were used to determine a day-to-day fasting glycaemic variability measure for each patient. For each patient, the variance of the three log-transformed pre-breakfast SMBG measurements each month was determined. The standard deviation was determined as the square root of the mean of these monthly variances and was defined as day-to-day fasting glycaemic variability. The associations between day-to-day fasting glycaemic variability and severe hypoglycaemia, MACE and all-cause mortality were analysed for the pooled trial population with Cox proportional hazards models. Several sensitivity analyses were conducted, including adjustments for baseline characteristics and most recent HbA1c. RESULTS: Day-to-day fasting glycaemic variability was significantly associated with severe hypoglycaemia (HR 4.11, 95% CI 3.15, 5.35), MACE (HR 1.36, 95% CI 1.12, 1.65) and all-cause mortality (HR 1.58, 95% CI 1.23, 2.03) before adjustments. The increased risks of severe hypoglycaemia, MACE and all-cause mortality translate into 2.7-, 1.2- and 1.4-fold risk, respectively, when a patient's day-to-day fasting glycaemic variability measure is doubled. The significant relationships of day-to-day fasting glycaemic variability with severe hypoglycaemia and all-cause mortality were maintained after adjustments. However, the significant association with MACE was not maintained following adjustment for baseline characteristics with either baseline HbA1c (HR 1.19, 95% CI 0.96, 1.47) or the most recent HbA1c measurement throughout the trial (HR 1.21, 95% CI 0.98, 1.49). CONCLUSIONS/INTERPRETATION: Higher day-to-day fasting glycaemic variability is associated with increased risks of severe hypoglycaemia and all-cause mortality. TRIAL REGISTRATION: ClinicalTrials.gov NCT01959529

Refined multiscale entropy using fuzzy metrics : validation and application to nociception assessment

The refined multiscale entropy (RMSE) approach is commonly applied to assess complexity as a function of the time scale. RMSE is normally based on the computation of sample entropy (SampEn) estimating complexity as conditional entropy. However, SampEn is dependent on the length and standard deviation of the data. Recently, fuzzy entropy (FuzEn) has been proposed, including several refinements, as an alternative to counteract these limitations. In this work, FuzEn, translated FuzEn (TFuzEn), translated-reflected FuzEn (TRFuzEn), inherent FuzEn (IFuzEn), and inherent translated FuzEn (ITFuzEn) were exploited as entropy-based measures in the computation of RMSE and their performance was compared to that of SampEn. FuzEn metrics were applied to synthetic time series of different lengths to evaluate the consistency of the different approaches. In addition, electroencephalograms of patients under sedation-analgesia procedure were analyzed based on the patient's response after the application of painful stimulation, such as nail bed compression or endoscopy tube insertion. Significant differences in FuzEn metrics were observed over simulations and real data as a function of the data length and the pain responses. Findings indicated that FuzEn, when exploited in RMSE applications, showed similar behavior to SampEn in long series, but its consistency was better than that of SampEn in short series both over simulations and real data. Conversely, its variants should be utilized with more caution, especially whether processes exhibit an important deterministic component and/or in nociception prediction at long scales

DEVOTE 3: temporal relationships between severe hypoglycaemia, cardiovascular outcomes and mortality

AIMS/HYPOTHESIS: The double-blind Trial Comparing Cardiovascular Safety of Insulin Degludec vs Insulin Glargine in Patients with Type 2 Diabetes at High Risk of Cardiovascular Events (DEVOTE) assessed the cardiovascular safety of insulin degludec. The incidence and rates of adjudicated severe hypoglycaemia, and all-cause mortality were also determined. This paper reports a secondary analysis investigating associations of severe hypoglycaemia with cardiovascular outcomes and mortality. METHODS: In DEVOTE, patients with type 2 diabetes were randomised to receive either insulin degludec or insulin glargine U100 (100 units/ml) once daily (between dinner and bedtime) in an event-driven, double-blind, treat-to-target cardiovascular outcomes trial. The primary outcome was the first occurrence of an adjudicated major adverse cardiovascular event (MACE; cardiovascular death, non-fatal myocardial infarction or non-fatal stroke). Adjudicated severe hypoglycaemia was the pre-specified secondary outcome. In the present analysis, the associations of severe hypoglycaemia with both MACE and all-cause mortality was evaluated in the pooled trial population using time-to-event analyses, with severe hypoglycaemia as a time-dependent variable and randomised treatment as a fixed factor. An investigation with interaction terms indicated that the effect of severe hypoglycaemia on the risk of MACE and all-cause mortality were the same for both treatment arms, and so the temporal association for severe hypoglycaemia with subsequent MACE and all-cause mortality is reported for the pooled population. RESULTS: There was a non-significant difference in the risk of MACE for individuals who had vs those who had not experienced severe hypoglycaemia during the trial (HR 1.38, 95% CI 0.96, 1.96; p = 0.080) and therefore there was no temporal relationship between severe hypoglycaemia and MACE. There was a significantly higher risk of all-cause mortality for patients who had vs those who had not experienced severe hypoglycaemia during the trial (HR 2.51, 95% CI 1.79, 3.50; p < 0.001). There was a higher risk of all-cause mortality 15, 30, 60, 90, 180 and 365 days after experiencing severe hypoglycaemia compared with not experiencing severe hypoglycaemia in the same time interval. The association between severe hypoglycaemia and all-cause mortality was maintained after adjustment for the following baseline characteristics: age, sex, HbA1c, BMI, diabetes duration, insulin regimen, hepatic impairment, renal status and cardiovascular risk group. CONCLUSIONS/INTERPRETATION: The results from these analyses demonstrate an association between severe hypoglycaemia and all-cause mortality. Furthermore, they indicate that patients who experienced severe hypoglycaemia were particularly at greater risk of death in the short term after the hypoglycaemic episode. These findings indicate that severe hypoglycaemia is associated with higher subsequent mortality; however, they cannot answer the question as to whether severe hypoglycaemia serves as a risk marker for adverse outcomes or whether there is a direct causal effect. TRIAL REGISTRATION: ClinicalTrials.gov NCT01959529