A systematic review of model-based economic evaluations of treatments for venous leg ulcers

Objective: The aim of this review was to identify, and assess the quality of, published model-based economic evaluations relating to treatments for patients with venous leg ulcers to help inform future decision-analytic models in this clinical area. Methods: A systematic literature search was performed on six electronic databases, from database inception until 21 May 2018. Search results were screened against predefined criteria by two independent reviewers. Data was then extracted from the included studies using a standardised form, whilst the decision-analytic model-specific Philips Checklist was used to assess quality and to inform model critique. Results: A total of 23 models were identified, 12 studies used a Markov modelling approach, five used decision trees and six studies did not detail the model type. Studies were predominantly from the National Health Service (NHS)/payer perspective, with only two taking a societal perspective. Interventions were wide ranging, but dressing technologies (11/23) were most common. The intervention studied was found to be dominant in 22/23 studies. The reporting quality of papers was mostly low, with evidence behind model structures, time horizons and data selection consistently underreported across the included papers. Conclusions: This review has identified a sizeable literature of model-based economic evaluations, evaluating treatments for venous leg ulcers. However, the methods used to conduct such studies were generally poorly reported. In particular, the reporting of evidence surrounding the model structure, justification of the time horizon used and the rationale for selecting data inputs should be focused on in any future models developed

An introduction to the methods of decision-analytic modelling used in economic evaluations for Dermatologists

Economic evaluations are used to identify which health treatments or preventions, offer the most effective use of resources, or value for money. This is achieved by identifying, measuring and valuing the inputs and outcomes of alternative interventions. These evaluations are often conducted alongside clinical trials, however these trials may end before the outcomes of economic interest have been observed and measured. An alternative to within trial economic evaluation is to use decision modelling, which can model the cost‐effectiveness of interventions over an extended time period. This paper aims to provide an overview for clinicians of the different modelling techniques used within health economic evaluations and to introduce methods for critical appraisal. The most common modelling approaches, and their associated strengths and weaknesses, were discussed. Alongside this, practical examples specific to dermatology were given. These examples include studies where the model chosen or the methods used may not have been the most appropriate. Methods for critical appraisal were also highlighted. Common modelling approaches include Decision Trees, Markov Cohort, extensions to the Markov model (Monte Carlo Simulation), and Discrete Event Simulation models. Items of the Philips Checklist were discussed in the context of performing critical appraisal. Health economic decision models are multi‐faceted and can often be complex. Full critical appraisal requires clinicians’ unique knowledge, which is complementary to the knowledge of health economists

Digital Problem-Based Learning: An Innovative and Efficient Method of Teaching Medicine

Background: The breadth of knowledge assimilated by undergraduates is substantial. Time must be utilised to impart knowledge and skills to ensure optimal training. Dermatology comprises a large portion of work in primary care; yet UK undergraduate dermatology training is short. Digital problem-based learning (PBL) is an innovative teaching method incorporating clinical images into intense, interactive teaching sessions. Aim: To determine the efficacy of digital PBL sessions in teaching UK medical students during their dermatology module. Methods: In total, 59 second-year medical students at Norwich Medical School during their dermatology secondary care attachment completed two 2.5-h digital PBL sessions. One session was focused on lesions and the second on inflammatory diseases. During each session, students assessed 60 clinical cases each comprising an image with a brief history. In small groups, students discussed the cases, described the images, and agreed a diagnosis followed by a group discussion with the supervising clinician who provided feedback. Following each session, students completed a feedback questionnaire. Results: In total, 117 sets of feedback were received; 60% of students considered they learnt a great amount in a short time. The majority of students reported feeling more confident to make a dermatological diagnosis and more motivated in clinics as a result of the digital PBL; 64% of students found digital PBL more useful than real patient clinics. The most frequent negative comment was that 2.5 h was too long to concentrate. Conclusions: Digital PBL was a popular, effective, and efficient teaching method. Digital PBL sessions should be introduced alongside clinics and other teaching methods for undergraduates

Inhibitors of Nitric Oxide Synthase in Human Skin

The aim of this study was to investigate in human skin in vivo the role of nitric oxide in maintaining resting vascular tone, in the vasodilatation caused by local warming and by ultraviolet B light exposure, and in the response to exogenous calcitonin gene-related peptide (CGRP). Cutaneous blood flow was assessed by planimetry of the visible erythema or pallor and by laser Doppler flowmetry. Intradermal injection of the inhibitor of nitric oxide synthase, NG-nitro-L-arginine methyl ester (L-NAME; 25 nmol), into forearm skin produced a visible pallor and a reduction of blood flow at a controlled ambient temperature of 21 degrees C. The control, NG-nitro-D-arginine methyl ester (D-NAME; 25 nmol) or NG-monomethyl-L-arginine (L-NMMA; 25 nmol) did not cause pallor or reduce blood flow. L-NAME and L-NMMA caused dose- and time-dependent increases in pallor, and reductions in cutaneous blood flow in skin that had been locally warmed by immersion in water at 45 degrees C and in skin that had been exposed to ultraviolet B light. D-NAME and D-NMMA at comparable concentrations did not have the effects on skin blood flow observed with the L forms. L-NAME and L-NMMA both inhibited the increased blood flow in human skin caused by the intradermal injection of CGRP (12.5 or 25 pmol). The reduction of CGRP-induced increase of blood flow by L-NAME was reversed by L-arginine. Neither D-NAME nor D-NMMA inhibited the increase in blood flow caused by CGRP. Neither L-NAME nor L-NMMA inhibited the increase in blood flow in human skin caused by the intradermal injection of prostaglandin E2 (63 pmol). The data show that nitric oxide is involved in the maintenance of resting blood flow in human skin and also in the cutaneous vasodilator responses to local warming, ultraviolet B irradiation, or injection of CGRP

Effect of a 2-week interruption in methotrexate treatment versus continued treatment on COVID-19 booster vaccine immunity in adults with inflammatory conditions (VROOM study):a randomised, open label, superiority trial

Background: Immunosuppressive treatments inhibit vaccine-induced immunity against SARS-CoV-2. We evaluated whether a 2-week interruption of methotrexate treatment immediately after the COVID-19 vaccine booster improved antibody responses against the S1 receptor-binding domain (S1-RBD) of the SARS-CoV-2 spike protein compared with uninterrupted treatment in patients with immune-mediated inflammatory diseases. Methods: We did an open-label, prospective, two-arm, parallel-group, multicentre, randomised, controlled, superiority trial in 26 hospitals in the UK. We recruited adults from rheumatology and dermatology clinics who had been diagnosed with an immune-mediated inflammatory disease (eg, rheumatoid arthritis, psoriasis with or without arthritis, axial spondyloarthritis, atopic dermatitis, polymyalgia rheumatica, and systemic lupus erythematosus) and who were taking low-dose weekly methotrexate (≤25 mg per week) for at least 3 months. Participants also had to have received two primary vaccine doses from the UK COVID-19 vaccination programme. We randomly assigned the participants (1:1), using a centralised validated computer randomisation program, to suspend methotrexate treatment for 2 weeks immediately after their COVID-19 booster (suspend methotrexate group) or to continue treatment as usual (continue methotrexate group). Participants, investigators, clinical research staff, and data analysts were unmasked, while researchers doing the laboratory analyses were masked to group assignment. The primary outcome was S1-RBD antibody titres 4 weeks after receiving the COVID-19 booster vaccine dose, assessed in the intention-to-treat population. This trial is registered with ISRCT, ISRCTN11442263; following the pre-planned interim analysis, recruitment was stopped early. Findings: Between Sept 30, 2021 and March 3, 2022, we recruited 340 participants, of whom 254 were included in the interim analysis and had been randomly assigned to one of the two groups: 127 in the continue methotrexate group and 127 in the suspend methotrexate group. Their mean age was 59·1 years, 155 (61%) were female, 130 (51%) had rheumatoid arthritis, and 86 (34%) had psoriasis with or without arthritis. After 4 weeks, the geometric mean S1-RBD antibody titre was 22 750 U/mL (95% CI 19 314–26 796) in the suspend methotrexate group and 10 798 U/mL (8970–12 997) in the continue methotrexate group, with a geometric mean ratio (GMR) of 2·19 (95% CI 1·57–3·04; p<0·0001; mixed-effects model). The increased antibody response in the suspend methotrexate group was consistent across methotrexate dose, administration route, type of immune-mediated inflammatory disease, age, primary vaccination platform, and history of SARS-CoV-2 infection. There were no intervention-related serious adverse events. Interpretation: A 2-week interruption of methotrexate treatment for people with immune-mediated inflammatory diseases resulted in enhanced boosting of antibody responses after COVID-19 vaccination. This intervention is simple, low-cost, and easy to implement, and could potentially translate to increased vaccine efficacy and duration of protection for susceptible groups. Funding: National Institute for Health and Care Research

Two-week interruption in methotrexate treatment versus treatment continued as usual and COVID-19 booster immunity in adults with inflammatory conditions (VROOM study): a randomised open label, superiority trial

Background Immunosuppressive treatments inhibit vaccine-induced immunity against SARS-CoV-2. We evaluated whether a 2-week interruption of methotrexate treatment immediately after the COVID-19 vaccine booster improved antibody responses against the S1 receptor-binding domain (S1-RBD) of the SARS-CoV-2 spike protein compared with uninterrupted treatment in patients with immune-mediated inflammatory diseases. Methods We did an open-label, prospective, two-arm, parallel-group, multicentre, randomised, controlled, superiority trial in 26 hospitals in the UK. We recruited adults from rheumatology and dermatology clinics who had been diagnosed with an immune-mediated inflammatory disease (eg, rheumatoid arthritis, psoriasis with or without arthritis, axial spondyloarthritis, atopic dermatitis, polymyalgia rheumatica, and systemic lupus erythematosus) and who were taking low-dose weekly methotrexate (≤25 mg per week) for at least 3 months. Participants also had to have received two primary vaccine doses from the UK COVID-19 vaccination programme. We randomly assigned the participants (1:1), using a centralised validated computer randomisation program, to suspend methotrexate treatment for 2 weeks immediately after their COVID-19 booster (suspend methotrexate group) or to continue treatment as usual (continue methotrexate group). Participants, investigators, clinical research staff, and data analysts were unmasked, while researchers doing the laboratory analyses were masked to group assignment. The primary outcome was S1-RBD antibody titres 4 weeks after receiving the COVID-19 booster vaccine dose, assessed in the intention-to-treat population. This trial is registered with ISRCT, ISRCTN11442263; following the pre-planned interim analysis, recruitment was stopped early. Findings Between Sept 30, 2021 and March 3, 2022, we recruited 340 participants, of whom 254 were included in the interim analysis and had been randomly assigned to one of the two groups: 127 in the continue methotrexate group and 127 in the suspend methotrexate group. Their mean age was 59·1 years, 155 (61%) were female, 130 (51%) had rheumatoid arthritis, and 86 (34%) had psoriasis with or without arthritis. After 4 weeks, the geometric mean S1-RBD antibody titre was 22 750 U/mL (95% CI 19 314–26 796) in the suspend methotrexate group and 10 798 U/mL (8970–12 997) in the continue methotrexate group, with a geometric mean ratio (GMR) of 2·19 (95% CI 1·57–3·04; p<0·0001; mixed-effects model). The increased antibody response in the suspend methotrexate group was consistent across methotrexate dose, administration route, type of immune-mediated inflammatory disease, age, primary vaccination platform, and history of SARS-CoV-2 infection. There were no intervention-related serious adverse events. Interpretation A 2-week interruption of methotrexate treatment for people with immune-mediated inflammatory diseases resulted in enhanced boosting of antibody responses after COVID-19 vaccination. This intervention is simple, low-cost, and easy to implement, and could potentially translate to increased vaccine efficacy and duration of protection for susceptible groups. Funding National Institute for Health and Care Research