Effect of metformin on outcome after acute ischemic stroke in patients with type 2 diabetes mellitus.

INTRODUCTION: Diabetes mellitus is a well-known risk factor for ischemic stroke and is associated with unfavorable outcome after stroke. Metformin is recommended as first-line treatment in these patients. Pre-stroke metformin use might have neuroprotective properties resulting in reduced stroke severity. However, results of the effects of pre-stroke metformin use on functional outcome are conflicting and has not been previously described in patients with type 2 diabetes mellitus regardless of stroke severity or revascularization treatment. In this study, we aimed to assess the association between metformin use and functional outcome in patients with type 2 diabetes mellitus and acute ischemic stroke. METHODS: We used data from patients with known type 2 diabetes mellitus who were admitted with acute ischemic stroke between 2017 and 2021 in the Isala Hospital Zwolle and Medisch Spectrum Twente (MST) Enschede, the Netherlands. The association between pre-stroke metformin use and favorable functional outcome at 3 months (defined as modified Rankin Scale (mRS) < 3) was expressed as Odds Ratios (ORs) with corresponding confidence intervals (CIs). Adjustments were made for age, sex, hyperglycemia on admission and revascularization treatment by means of multiple logistic regression. RESULTS: Nine hundred thirty seven patients were included of whom 592 patients (63%) used metformin. Six hundred seventy eight (74%) patients were hyperglycemic on admission. Median mRS was 3 (IQR 2-6) and 593 patients (63%) had a favorable outcome. Pre-stroke metformin use was associated with favorable outcome (aOR of 1.94 (95%- CI 1.45-2.59)). CONCLUSION: In this study, we showed that pre-stroke metformin use was associated with favorable outcome after acute ischemic stroke in patients with diabetes mellitus type 2.

Association of hyperglycemia and computed tomographic perfusion deficits in patients who underwent endovascular treatment for acute ischemic stroke caused by a proximal intracranial occlusion: A subgroup analysis of a randomized phase 3 trial (MR CLEAN).

INTRODUCTION: Hyperglycemia is highly prevalent in patients with acute ischemic stroke and is associated with increased risk of symptomatic intracranial hemorrhage, larger infarct size and unfavorable outcome. Furthermore, glucose may modify the effect of endovascular treatment (EVT) in patients with ischemic stroke. Hyperglycemia might lead to accelerated conversion of penumbra into infarct core. However, it remains uncertain whether hyperglycemia on admission is associated with the size of penumbra or infarct core in acute ischemic stroke. In this study, we aimed to assess the association between hyperglycemia and Computed Tomographic Perfusion (CTP) derived parameters in patients who underwent EVT for acute ischemic stroke. METHODS: We used data from the MR CLEAN study (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands). Hyperglycemia was defined as admission serum glucose of >7.8 mmol/L. Dichotomized and quantiles of glucose levels were related to size of core, penumbra and core penumbra ratio. Hypoperfused area is mean transient time 45% higher than that of the contralateral hemisphere. Core is the area with cerebral blood volume of <2 mL/100 g and penumbra is the area with cerebral blood volume > 2 mL/100 g. Core-penumbra ratio is the ischemic core divided by the total volume of hypoperfused tissue (core plus penumbra) multiplied by 100. Adjustments were made for age, sex, NIHSS on admission, onset-imaging time and diabetes mellitus. RESULTS: Hundred seventy-three patients were included. Median glucose level on admission was 6.5 mmol/L (IQR 5.8-7.5 mmol/L) and thirty-five patients (20%) were hyperglycemic. Median core volume was 33.3 mL (IQR 13.6-62.4 mL), median penumbra volume was 80.2 mL (IQR 36.3-123.5 mL) and median core-penumbra ratio was 28.5% (IQR 18.6-45.8%). Patients with hyperglycemia on admission had larger core volumes and core penumbra ratio than normoglycemic patients with a regression coefficient of 15.1 (95% confidence interval (CI), 1.8 to 28.3) and 11.5 (95% confidence interval (CI), 3.4 to 19.7) respectively. CONCLUSION: Hyperglycemia on admission was associated with larger ischemic core volume and larger core-penumbra ratio in patients with acute ischemic stroke who underwent endovascular treatment.

Using a stepwise approach to simultaneously develop and validate machine learning based prediction models.

Accurate diagnosis of a disease is essential in healthcare. Prediction models, based on classical regression techniques, are widely used in clinical practice. Machine Learning (ML) techniques might be preferred in case of a large amount of data per patient and relatively limited numbers of subjects. However, this increases the risk of overfitting, and external validation is imperative. However, in the field of ML, new and more efficient techniques are developed rapidly, and if recruiting patients for a validation study is time consuming, the ML technique used to develop the first model might have been surpassed by more efficient ML techniques, rendering this original model no longer relevant. We demonstrate a stepwise design for simultaneous development and validation of prediction models based on ML techniques. The design enables - in one study - evaluation of the stability and robustness of a prediction model over increasing sample size as well as assessment of the stability of sensitivity/specificity at a chosen cut-off. This will shorten the time to introduction of a new test in health care. We finally describe how to use regular clinical parameters in conjunction with ML based predictions, to further enhance differentiation between subjects with and without a disease.

Differentiation between infected and non-infected wounds using an electronic nose.

OBJECTIVES: The aim of this study was to explore whether an electronic nose, Aetholab, is able to discriminate between infected versus non-infected wounds, based on headspace analyses from wound swabs. METHODS: A total of 77 patients participated in this pilot study. Each wound was assessed for infection based on clinical judgment. Additionally, two wound swabs were taken, one for microbiological culture and one for measurement with Aetholab. Diagnostic properties with 95% confidence intervals (95%CIs) of Aetholab were calculated with clinical judgment and microbiological culture results as reference standards. RESULTS: With clinical judgment as reference standard, Aetholab had a sensitivity of 91% (95%CI 76-98) and a specificity of 71% (95%CI 55-84). Diagnostic properties were somewhat lower when microbiological culture results were used as reference standard: sensitivity 81% (95%CI 64-91), specificity 63% (95%CI 46-77). CONCLUSIONS: Aetholab seems a promising diagnostic tool for wound infection given the diagnostic properties presented in this pilot study. A larger study is needed to confirm our results.

Culture results from wound biopsy versus wound swab: does it matter for the assessment of wound infection?

OBJECTIVES: The aim of this study was to determine whether assessment of wound infection differs when culture results from wound biopsy versus wound swab are available in clinical practice. METHODS: For 180 eligible patients, a swab and biopsy were taken from one wound during a regular appointment at a wound care facility in eastern Netherlands. Culture results from both methods were supplemented with clinical information and provided to a panel of six experts who independently assessed each wound as infect or not, separately for swab and biopsy. Assessments for biopsy and swab were compared for the complete expert panel, and for individual experts. RESULTS: The complete expert panel provided the same wound assessment based on (clinical information and) culture results from wound biopsy and wound swab in 158 of 180 wounds (87.8%, kappa 0.67). For individual experts, agreement between biopsy and swab varied between 77% and 96%. However, there were substantial differences between experts: the same assessment was provided in 62 (34.4%) to 76 (42.2%) wounds for swab and biopsy respectively. CONCLUSIONS: Assessment of infection does not significantly differ when culture results from swabs or biopsies are available. The substantial variability between individual experts indicates non-uniformity in the way wounds are assessed. This complicates accurate detection of infection and comparability between studies using assessment of infection as reference standard.