Comparison of diabetes-associated secondary healthcare utilization between alternative oral antihyperglycaemic dual therapy combinations with metformin in patients with type 2 diabetes: an observational cohort study

AIMS

To compare diabetes-associated secondary healthcare utilization in patients with type 2 diabetes (T2DM) prescribed sulphonylureas (SUs) versus other oral antihyperglycaemic agents (OHAs) as an add-on to metformin monotherapy (metformin + SU vs metformin + OHA).

METHODS

This retrospective cohort study used data from the Clinical Practice Research Datalink linked to Hospital Episode Statistics. Adults with T2DM initiated on metformin + SU or metformin + OHA from April 2003 to March 2012 were identified. Patients were matched using propensity scores. Diabetes-associated secondary healthcare visits were counted from >6 months post-initiation of dual therapy until treatment change or end of follow-up. Outcomes were calculated as rate ratios, adjusted for over-dispersion using negative binomial regression and propensity score for covariates.

RESULTS

After propensity score matching, 1704 patients were included in each cohort. For the primary objective (diabetes-associated inpatient and outpatient visits combined), the metformin + SU cohort had a directionally higher rate of diabetes-associated secondary healthcare utilization than the metformin + OHA cohort [adjusted rate ratio 1.12, 95% confidence interval (CI) 0.97-1.29]. For the secondary outcomes, the adjusted rate ratio was 1.38 (95% CI 0.95-2.00) for inpatient admissions and 1.10 (95% CI 0.95-1.28) for outpatient visits. Macrovascular complications, accounting for 77.2% of inpatient admissions, occurred at a statistically significantly higher rate in the metformin + SU cohort than in the metformin + OHA cohort (adjusted rate ratio 1.77, 95% CI 1.15-2.71).

CONCLUSIONS

This study found a statistically significant higher rate of inpatient admissions for macrovascular complications and cardiology outpatient visits and, overall, a directionally higher rate of secondary healthcare utilization for patients prescribed metformin + SU than for those prescribed metformin + OHA. This adds to the evidence that long-term and health economic outcomes should be considered in treatment decisions for patients with type 2 diabetes.

A mechanostatistical approach to cortical bone remodelling: an equine model

In this study, the development of a mechanostatistical model of three-dimensional cortical bone remodelling informed with in vivo equine data is presented. The equine model was chosen as it is highly translational to the human condition due to similar Haversian systems, availability of in vivo bone strain and biomarker data, and furthermore, equine models are recommended by the US Federal Drugs Administration for comparative joint research. The model was derived from micro-computed tomography imaged specimens taken from the equine third metacarpal bone, and the Frost-based 'mechanostat' was informed from both in vivo strain gauges and biomarkers to estimate bone growth rates. The model also described the well-known 'cutting cone' phenomena where Haversian canals tunnel and replace bone. In order to make this model useful in practice, a partial least squares regression (PLSR) surrogate model was derived based on training data from finite element simulations with different loads. The PLSR model was able to predict microstructure and homogenised Young's modulus with errors less than 2.2% and 0.6%, respectively.

Measurement of the inclusive electron neutrino charged current cross section on carbon with the T2K near detector

The T2K off-axis near detector ND280 is used to make the first differential cross-section measurements of electron neutrino charged current interactions at energies ∼1  GeV as a function of electron momentum, electron scattering angle, and four-momentum transfer of the interaction. The total flux-averaged ν(e) charged current cross section on carbon is measured to be ⟨σ⟩(ϕ)=1.11±0.10(stat)±0.18(syst)×10⁻³⁸ cm²/nucleon. The differential and total cross-section measurements agree with the predictions of two leading neutrino interaction generators, NEUT and GENIE. The NEUT prediction is 1.23×10⁻³⁸ cm²/nucleon and the GENIE prediction is 1.08×10⁻³⁸ cm²/nucleon. The total ν(e) charged current cross-section result is also in agreement with data from the Gargamelle experiment.

Precise measurement of the neutrino mixing parameter θ23 from muon neutrino disappearance in an off-axis beam

New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter θ23. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57×10(20) protons on target, T2K has fit the energy-dependent νμ oscillation probability to determine oscillation parameters. The 68% confidence limit on sin(2)(θ23) is 0.514(-0.056)(+0.055) (0.511±0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Δm32(2)=(2.51±0.10)×10(-3)  eV(2)/c(4) (inverted hierarchy: Δm13(2)=(2.48±0.10)×10(-3)  eV(2)/c(4)). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty.

Impact of iron deficiency on hemoglobin A2% in obligate β-thalassemia heterozygotes

INTRODUCTION

The potential impact of concomitant iron deficiency on hemoglobin A2 (HbA2)-based identification of β-thalassemia trait (βTT) is a worrisome issue for screening laboratories. This is especially true for resource-constrained settings where iron deficiency is widespread and molecular confirmatory tests for borderline low HbA2 values may be unavailable.

METHODS

Obligate βTT carrier individuals (n = 752) were identified during screening studies on the parents of thalassemia major patients. HbA2%, complete blood counts and serum iron, ferritin and transferrin saturation were studied. Iron-deficient individuals (n = 135) with normal range HbA2% were taken as controls.

RESULTS

Concomitant iron deficiency (defined as ferritin ≤15 ng/mL and/or transferrin saturation ≤15%) was present in 20.7% (156/752) βTT cases, that is, 33.3% females (122/366) and 8.8% males with βTT (34/386). Mean HbA2 in iron-replete βTT was 5.4 ± 0.8 (range 3.1-7.9) and in iron-deficient βTT was 5.4 ± 0.9 (range 3.3-7.6). HbA2 < 4.0% was found in 23/752 (3.1%) βTT: 13/595 iron-replete (2.2%) and 10/157 (6.4%) iron-deficient βTT individuals. However, five of the 10 iron-deficient βTT cases carried the silent CAP+1 (A>C) β-thalassemia allele accounting for the borderline HbA2%. On a separate analysis, all five severely anemic βTT (Hb < 80 g/L) and 16/17 βTT with severe hypoferritinemia (<5 ng/mL) had HbA2 > 4.5%. The single case with serum ferritin 4.8 ng/mL and HbA2 3.3% showed a CAP+1 (A>C) mutation.

CONCLUSIONS

Iron deficiency was prevalent among north Indian βTT individuals, especially women. After adjusting for other causes of low HbA2 in βTT, iron deficiency, even when very severe, was very unlikely to interfere significantly with HbA2-based identification of βTT.

Observation of electron neutrino appearance in a muon neutrino beam

The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3σ when compared to 4.92±0.55 expected background events. In the Pontecorvo-Maki-Nakagawa-Sakata mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles θ12, θ23, θ13, a mass difference Δm(32)(2) and a CP violating phase δ(CP). In this neutrino oscillation scenario, assuming |Δm(32)(2)|=2.4×10(-3)  eV(2), sin(2)θ(23)=0.5, and Δm322>0 (Δm(32)(2)<0), a best-fit value of sin(2)2θ(13)=0.140(-0.032)(+0.038) (0.170(-0.037)(+0.045)) is obtained at δ(CP)=0. When combining the result with the current best knowledge of oscillation parameters including the world average value of θ(13) from reactor experiments, some values of δ(CP) are disfavored at the 90% C.L.

Suppressive activity and altered conventional phenotype markers/mediators of regulatory T cells in patients with self-limiting hepatitis E

Hepatitis E virus (HEV) is a major cause of self-limiting acute viral hepatitis in several developing countries. Elevated levels of peripheral CD4(+) CD25(+) Foxp3(+) , CD4(+) CD25(-) Foxp3(+) and rise in IL-10 in hepatitis E have been associated with the involvement of regulatory T cells (Treg). The functional role of the same is yet elusive. In the current study, we have assessed (i) Foxp3 expression by real-time PCR and by flow cytometry, (ii) the levels of antigen-specific IL-10 and TGF-β by ELISA, (iii) functional analysis of Treg cells and (iv) expression of Treg-associated conventional phenotypes by flow cytometry in 54 acute patients, 44 recovered individuals from hepatitis E and in 33 healthy controls. Foxp3 mRNA elevation in the acute compared with recovered group and elevation in Foxp3(+) cells in both patient groups were significantly elevated. The levels of IL-10 and TGF-β in the acute patients and TGF-β in the recovered individuals were elevated. Significantly higher expression of CTLA-4, PD1, GITR, CD95, CD103 and CD73 on Treg and T effector (Teff) cells was detected in the patient groups. Treg cells of acute patients and recovered individuals exhibited suppressive activity indicating that the Treg cells of hepatitis E patients are functional. The suppressive capacity of Treg cells in acute hepatitis E patients was significantly higher compared with the recovered individuals. Based on our findings, the suppressive functionality of these key markers associated with hepatitis E Treg function need further exploration to get a better understanding of the mechanisms of Treg-mediated suppression.