PURPOSE:: This cross-sectional study aimed to investigate the association between hamstring muscle peak torque and rapid force capacity (rate of torque development: RTD) versus sprint performance in elite youth football players.

METHODS:: Thirty elite academy youth football players (16.75 ± 1.1 years, 176.9 ± 6.7 cm, 67.1 ± 6.9 kg) were included. Isometric peak torque (Nm/kg) and early (0-100 ms) and late (0-200 ms) phase RTD (RTD100, RTD200) (Nm/s/kg) of the hamstring muscles were obtained as independent predictor variables. Sprint performance was assessed during a 30-m sprint trial. Mechanical sprint variables (maximal horizontal force production (FH0) (N/kg); maximal theoretical velocity (V0) (m/s); maximal horizontal power output (Pmax) (W/kg)) and sprint split times (0-5 m; 0-15 m; 0-30 m; 15-30 m) (s) were derived as dependent variables. Subsequently, linear regression analysis was conducted for each pair of dependent and independent variables.

RESULTS:: Positive associations were observed between hamstring RTD100 and FH0 (r2=0.241, p=0.006) and Pmax (r2=0.227, p=0.008). Furthermore, negative associations were observed between hamstring RTD100 and 0-5 m (r2=0.206, p=0.012), 0-15 m (r2=0.217, p=0.009) and 0-30 m sprint time (r2=0.169, p=0.024). No other associations were observed.

CONCLUSION:: The present data indicate that early-phase (0-100 ms) rapid force capacity of the hamstring muscles plays an important role for the acceleration capacity in elite youth football players. In contrast, no associations were observed between hamstring muscle function and maximal sprint velocity. This indicates that strength training focusing on improving early-phase hamstring rate of force development may contribute to enhance sprint acceleration performance in this athlete population.

BACKGROUND AND OBJECTIVE: Qualitative methods such as semi-structured interviews and focus-groups are used to evaluate the applicability and relevance of device technologies in clinical practice, but when used alone, often lack generalizability. This study aimed to assess the face validity and feasibility of using a composite, three-step qualitative method (the Parker Model), to inform the development and implementation of ava®, an electromechanical device (e-Device) for subcutaneous self-administration of the biologic, certolizumab pegol (CZP), used to treat rheumatic diseases.

METHODS: The Parker Model combines concept mapping (CM), participatory design (PD), and stakeholder evaluation (SE). CM, a structured group process, was used to identify patients' opinions and concerns regarding the e-Device. Patients used this information in iterative PD sessions to create personal e-Device prototypes in cooperation with a designer and a healthcare professional. SE was performed based on semi-structured group and individual interviews with patients and disease-management stakeholders.

RESULTS: The study recruited 14 patients, two doctors, two nurses, one medical secretary, and four other public servants. Three CM workshops revealed four key considerations: technical usability, physical design, concerns, and enthusiasm. Four personalized prototypes were developed during PD sessions. SE confirmed that the identified considerations were pivotal for the implementation and adaptation of the e-Device.

CONCLUSIONS: This study is the first to apply a composite, qualitative research model when introducing an e-Device for the treatment and management of rheumatic disease. Results show that input from patients and other stakeholders using the Parker Model can add value to the development and implementation of an e-Device.

BACKGROUND: Exercise reduces the amount of visceral adipose tissue (VAT) and the risk of cardiometabolic diseases. The underlying mechanisms responsible for these exercise-induced adaptations are unclear, but they may involve lipolytic actions of interleukin-6 (IL-6). Contracting skeletal muscles secrete IL-6, leading to increased circulating IL-6 levels in response to exercise. The aim of this study is to investigate whether IL-6 is involved in mediating the effects of exercise on visceral and epicardial adipose tissue volume and glycaemic control.

METHODS/DESIGN: Seventy-five physically inactive males and females aged > 18 years with a waist-to-height ratio > 0.5 and/or waist circumference ≥ 88 cm (females) or ≥ 102 cm (males) are being recruited to participate in a 12-week intervention study. Participants are randomly allocated to one of five groups (1:1:1:1:1). Two groups consist of supervised endurance exercise training combined with the IL-6 blocker tocilizumab (ET) or saline used as placebo (EP), two groups consist of no exercise combined with tocilizumab (NT) or placebo (NP), and one group consists of resistance exercise and placebo (RP). Although the study is an exploratory trial, the primary outcome is change in VAT volume from before to after intervention, with secondary outcomes being changes in (1) epicardial adipose tissue, (2) pericardial adipose tissue and (3) gastric emptying. Depots of adipose tissue are quantitated by magnetic resonance imaging Gastric emptying and glucose metabolism are assessed using mixed-meal tolerance tests.

DISCUSSION: Understanding the role of IL-6 in mediating the effects of exercise on visceral and epicardial adipose tissue and glycaemic control may lead to novel therapeutic approaches in the prevention of cardiometabolic diseases.

TRIAL REGISTRATION: ClinicalTrials.gov, NCT02901496 . Registered on 1 August 2016 and posted retrospectively on 15 September 2016.

OBJECTIVES: Real-world evidence on effectiveness of switching to biosimila r etanercept is scarce. In Denmark, a nationwide guideline of mandatory switch from 50 mg originator (ETA) to biosimilar (SB4) etanercept was issued for patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA) in 2016. Clinical characteristics and treatment outcomes were studied in ETA-treated patients, who switched to SB4 (switchers) or maintained ETA (non-switchers). Retention rates were compared with that of a historic cohort of ETA-treated patients. Switchers who resumed ETA treatment (back-switchers) were characterised.

METHODS: Observational cohort study based on the DANBIO registry. Treatment retention was explored by Kaplan-Meier plots and Cox regression (crude, adjusted).

RESULTS: 1621 (79%) of 2061 ETA-treated patients switched to SB4. Disease activity was unchanged 3 months' preswitch/postswitch. Non-switchers often received 25 mg ETA (ETA 25 mg pens/syringes and powder solution were still available). One-year adjusted retention rates were: non-switchers: 77% (95% CI: 72% to 82%)/switchers: 83% (79% to 87%)/historic cohort: 90% (88% to 92%). Patients not in remission had lower retention rates than patients in remission, both in switchers (crude HR 1.7 (1.3 to 2.2)) and non-switchers (2.4 (1.7 to 3.6)). During follow-up, 120 patients (7% of switchers) back-switched to ETA. Back-switchers' clinical characteristics were similar to switchers, and reasons for SB4 withdrawal were mainly subjective.

CONCLUSION: Seventy-nine per cent of patients switched from ETA to SB4. After 1 year, adjusted treatment retention rates were lower in switchers versus the historic ETA cohort, but higher than in non-switchers. Withdrawal was more common in patients not in remission. The results suggest that switch outcomes in routine care are affected by patient-related factors and non-specific drug effects.

OBJECTIVE: We undertook a systematic review and meta-analysis of direct and indirect trial evidence to evaluate the efficacy of treatments for patients with undifferentiated arthritis (UA).

METHODS: We searched 4 electronic databases from inception to January 2016, clinicaltrials.gov, and bibliographies of relevant articles. Two reviewers independently screened and evaluated the studies. The primary outcome was development of rheumatoid arthritis (RA).

RESULTS: Nine studies were included. Interventions included methotrexate, abatacept, infliximab, intraarticular or intramuscular glucocorticoids, and radiation synovectomy. Treating patients resulted in lower rates of RA at 12 months compared to placebo or no treatment (odds ratio [OR] 0.49 [95% confidence interval (95% CI) 0.26, 0.90]). From direct meta-analysis, patients treated with methotrexate were less likely to develop RA at 12 months compared to patients treated without methotrexate (OR 0.13 [95% CI 0.03, 0.48]). This difference was no longer significant at 30 or 60 months. From indirect comparisons, most interventions showed decreased risk of developing RA compared to placebo at 12 months, reaching statistical significance for methotrexate (OR 0.16 [95% CI 0.08, 0.33]) and intramuscular methylprednisolone (OR 0.72 [95% CI 0.53, 0.99]). Most individual interventions included a limited number of studies.

CONCLUSION: Treating patients with UA resulted in a statistically significant delay in the development of RA, with the largest effect observed for methotrexate. These findings suggest that there is a window of opportunity to treat patients with UA early, to delay subsequent progression to RA.

OBJECTIVES: To assess the importance of trial characteristics as contextual factors when evaluating treatment effect of targeted therapies for patients with psoriatic disease.

METHODS: We identified randomized controlled trials (RCTs) evaluating targeted therapies approved for psoriatic arthritis (PsA) and psoriasis (8 biologics and apremilast). The effect of targeted therapies was analyzed in the two psoriatic conditions combined by using drug retention as common outcome, and separately by using ACR20 for PsA and PASI75 for psoriasis. We explored potential effect modification of trial characteristics in stratified and meta-regression analyses. Odds ratios (OR) were calculated and compared among the trial eligibility criteria via the Ratio of Odds Ratios (ROR).

RESULTS: Forty-eight PsA and psoriasis trials (51 comparisons, 17,737 patients) were eligible. Overall retention was OR 2.16 (1.70 to 2.75) with higher odds for PsA trials compared with psoriasis trials (ROR = 2.55 [1.64 to 3.97]). The eligibility criteria "targeted therapy history", "minimum required disease duration", "required negative rheumatoid factor", and "required CASPAR criteria" were of importance for achieving ACR20 in PsA. The eligibility criterion "minimum required disease duration" was of importance for achieving PASI75 in psoriasis. 7 PsA trials had rescue before time point of retention reporting (adaptive trials).

CONCLUSION: From this exploratory meta-epidemiological study we now have evidence from RCTs to support that patients with PsA are more likely to adhere to targeted therapies compared to patients with psoriasis. Furthermore, we identified a few contextual factors of importance in regard to achieving ACR20 in PsA trials and PASI75 in psoriasis trials. This article is protected by copyright. All rights reserved.