Tapering Strategy Research Articles

Tapering strategies applied to plyometric jump training: a systematic review with meta-analysis of randomized-controlled trials.

The purpose of this systematic review was to analyze the effect of plyometric jump training (PJT) applied in conjunction with tapering strategies on the jump performance of team-sport athletes. The meta-analysis included: 1) randomized-controlled studies that incorporated a PJT program; 2) cohorts of team-sport athletes; 3) jump performance assessments; and 4) studies that incorporated a programmed taper. A systematic search was conducted in distinct electronic databases for relevant studies. Aside from jump performance, the extracted data included characteristics of the participants, PJT, and tapering. Means and standard deviations were used to calculate the effect sizes (ES). To assess the effects of moderator variables, subgroup analyses were performed. The statistical significance level was set as P<0.05. From 7020 records initially identified, 14 studies were eligible for meta-analysis. Across all included studies, there was a moderate, significant improvement in jump performance (ES=0.73; P<0.001). Additionally, the subgroup analysis demonstrated that the duration and intensity of the taper and the volume of the PJT induced similar improvements in jump performance (P<0.01). In summary, PJT interventions that included a programmed taper induced significant improvements in jump performance in team-sport athletes. These effects were observed after different tapering strategies in terms of volume, taper duration, and the type of PJT prescribed.

Soreness And Fatigue As The Key Perceptual Indicators For Previous Day Workload In Athletes

PURPOSE: As monitoring of athletes has become prominent throughout competitive sport, objective and subjective methods have proven valuable in informing of an athlete’s physical condition and preparedness. However, it remains unclear how objective load metrics are reflected in self-reported subjective indices. Thus, the purpose of this study was to examine the relationship between objective markers of workload and subjective assessments of soreness, fatigue, and stress the following day. METHODS: Twenty-six collegiate male soccer players (mean±SD; 20±1y; 75.83±5.90kg; 178.5±6.8cm) wore GPS-enabled heart rate monitors during every training session and match within the 2017 season. Objective load variables (total distance covered (TD), number of sprints (SP), number of accelerations (AC), number of decelerations (DC), and training load (TL)) were collected each day. Subjective load (soreness, fatigue, and stress) were reported on a 1-10 Likert scale the following morning. Mixed models tested the relation between subjective metrics and the objective metrics of the previous day’s training or match. RESULTS: Training load and deceleration numbers from the day before showed significant relevance to reported scores of soreness and fatigue. Heavier training loads resulted in higher soreness and fatigue scores (TL P=<0.001), just as lighter training loads resulted in lower soreness and fatigue scores. A similar positive correlation was found with the number of decelerations to reported soreness and fatigue (DC P=0.023). CONCLUSIONS: Lasting physiological impacts of the previous day’s training load and decelerations were reflected in player-reported soreness and fatigue the following morning. This information may be utilized by coaching staff to; 1) adjust training based on subjective metric scores and 2) inform tapering strategies to maximize performance in matches.

Are treat-to-target and dose tapering strategies for rheumatoid arthritis possible during the COVID-19 pandemic?

The global pandemic of COVID-19 has dramatically altered the delivery of rheumatology outpatient services because of the redeployment of staff and efforts to minimise infection risk to patients and clinicians in line with physical distancing guidance. Departments have converted most face-to-face appointments to telephone clinics or, less frequently, to video clinics. The National Institute for Health and Care Excellence (NICE) COVID-19 rapid guidelines for rheumatology suggest that face-to-face consultations are only required for patients who have a disease flare.

AB0283 REDUCED HOSPITAL ADMISSION IN RA PATIENTS TAPERING BIOLOGIC DMARDS: PRELIMINARY ANALYSIS OF A RETROSPECTIVE STUDY

Background:bDMARDs are among the most effective therapies in the management of inflammatory arthritides, but they are associated with potentially severe adverse events (AEs), particularly infection. Tapering strategies of bDMARDs for patients in remission/low disease activity (R/LDA) have demonstrated comparable efficacy to standard-dose treatments, but their safety profile has not been studied yet.Objectives:To compare the number and the causes of hospital admissions in RA patients in R/LDA continuing or tapering bDMARDs.Methods:Consecutive patients with rheumatoid arthritis (RA) evaluated between 2011 and 2017, were assigned, based on treating physician’s discretion, to continue the standard dose (STD) of bDMARDs or to undergo a predetermined tapering strategy (TAP), after being in R/LDA for two consecutive visits at least 3 months apart. Down-titration of bDMARDs was obtained by a stepwise increase of the dosing interval to achieve a reduction of about 30% (e.g. administration of etanercept every 10 days instead of weekly). Demographic, clinical data and concomitant treatments were retrospectively retrieved from the electronic charts of the outpatient clinics. Information about hospital admissions, including main diagnosis, period and duration of hospitalization, and death were retrieved from the Regional Healthcare System Database.For the STD group, the observation period started with the occurrence of remission and finished with one of these events: loss of remission, switch to another bDMARD, withdrawal of the bDMARD, severe AE, death, end of the study period in (December 2017). For the TAP group, the observation period started with tapering onset and finished with one of these events: reduction of the dosing interval due to either a relapse (according to a DAS28 increase) or to a subjective, symptomatic relapse (according to the patient’s definition), switch to another bDMARD, withdrawal of the bDMARD, severe AE, death, end of the study period in (December 2017).Results:81 patients were included, of whom 40 underwent TAP. Demographic, clinical and treatment data are shown in table 1. Baseline characteristics were comparable between the two groups, except for the number of previous bDMARDs before observational period entry that was slightly higher in the STD group (STD 1.0±0.9 versus TAP 0.5±0.8, P=0.11).Table 1.Baseline demographic and clinical characteristics of the patients in remission or low disease activity.NO TAPERING(n=41)TAPERING(n=40)p valueMean age (yrs)57±1158±130.563Mean disease duration (yrs)12±912±70.897Starting bDMARD to tapering/monitoring (months)52±4567±410.128Mean monitoring period (months)22±2419±230.632Taking sDMARD at any time ((n (%))40 (98%)37 (92%)0.359Taking glucocorticoids29 (71%)28 (70%)0.999Mean prednisone dose (mg/day)2.5±2.92.1±2.70.527DAS28 at the time of tapering or first LDA/REM2.3±0.82.3±0.90.863Previous bDMARDs &gt;1 (n (%))10 (24.4%)4 (10%)0.140In the STD group, 14 hospital admissions occurred, while in the TAP group there were 7 admissions (p=0.128). The corresponding figures for hospital admission due to infectious diseases were 6 in the STD group and 0 in the TAP group (p=0.026).Conclusion:Tapering bDMARDs in RA patients in R/LDA is associated with fewer hospital admissions, with a possible protective effect especially toward infections.Acknowledgments:The authors are indebted with Mrs Rosella Gramuglia and Mrs Cristina Olivieri for the management and analysis of the data on the flow of the drugs, and with Mrs Anna Consigliere, Mrs Anna Cosso, Mrs Romina Petralito and Mrs Laura Ravaschio for helping in retrieving clinical data.Disclosure of Interests:Dario Camellino Consultant of: I have received consultancy fees from Celgene, Sanofi, Novartis, Janssen-Cilag, Accord, Paid instructor for: I have served as a paid instructor for Mylan, Andrea Giusti Consultant of: UCB, Amgen, Janssen, Eli Lilly, Abiogen, EffRx, Speakers bureau: UCB, Amgen, Janssen, Eli Lilly, Abiogen, EffRx, Alfa-Sigma, Chiesi, Giuseppe Girasole: None declared, Chiara Craviotto: None declared, Paola Diana: None declared, Antonia Locaputo: None declared, Tiziana Caviglia: None declared, Lacramioara Luca: None declared, Gerolamo Bianchi Consultant of: Amgen, Janssen, Merck Sharp &amp; Dohme, Novartis, UCB, Speakers bureau: Abbvie, Abiogen, Alfa-Sigma, Amgen, BMS, Celgene, Chiesi, Eli Lilly, GSK, Janssen, Medac, Merck Sharp &amp; Dohme, Novartis, Pfizer, Roche, Sanofi Genzyme, Servier, UCB

Tapering towards DMARD-free remission in established rheumatoid arthritis: 2-year results of the TARA trial

ObjectivesTo evaluate the 2-year clinical effectiveness of two gradual tapering strategies. The first strategy consisted of tapering the conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) first (i.e., methotrexate in ~90%), followed...

Monitoring Workloads of a Professional Female Futsal Team over a Season: A Case Study.

The aims of this study were to describe the external and internal workloads in a professional female futsal team during a whole season and to compare workloads during different periods of the season. Ten professional female futsal players (age 22.8 ± 4.3 years; 5.1 ± 2.4 years of experience; weight 61.9 ± 7.1 kg; height 1.66 ± 0.06 m) participated voluntarily in this study during the whole season. The internal workload was measured by the session-Rate of perceived exertion (session-RPE) method, while the external workload was indirectly measured by considering the training and match volume and the type of contents of each session over 43 weeks. Mean sRPE throughout the season was 319.9 ± 127.1 arbitrary units (AU). Higher internal loads (total weekly training load and strain) were reported during the pre-season compared with the in-season mesocycles (p < 0.05); meanwhile, the fifth to eighth mesocycles of the in-season showed an oscillatory pattern. Finally, Monday was the most-demanding session during the in-season period over the Thursday (p < 0.05; effect size: 1.33) followed by match day, meanwhile no statistical differences were reported during different sessions of the pre-season microcycle (p > 0.05). This study suggests that microcycles of pre-season present a stable load pattern, meanwhile workloads during the in-season period report a tapering strategy in a professional female futsal team.

Tapering Recommendations for Benzodiazepines

Tapering Recommendations for Benzodiazepines

External and internal Load and their Effects on Professional Volleyball Training

The purpose of this study was twofold: (i) characterize the external and internal training load of professional volleyball players with a focus on intra-week changes and (ii) test the relationships between internal and external load measures. Eight male professional players (age: 23.0±5.22 yo; body mass: 84.5 ± 7.58 kg; height: 193.0±9.71 cm; BMI: 22.0±0.02 kg/m2) were monitored daily over 15 weeks. The monitoring process included both internal (rate of perceived exertion [RPE] and session-RPE [s-RPE]) and external load variables, which were measured by an inertial measurement unit. Results revealed that, within-week variations revealed that RPE was significantly higher during MD-2 (d=0.59) and MD-3 (d=0.56) than MD-1. A significantly higher number of jumps was observed on MD-2 than MD-1 (d=0.69). Considering the relationships between internal and external load measures, small positive correlations were found between RPE and the number of jumps (r=0.17) and between s-RPE and the number of jumps (r=0.49). In conclusion, a tapering strategy was observed on the day before a match, as internal and external loads decreased. Both internal and external load measures are necessary to provide an accurate perception of the impact of training stimuli on players.

Health complaints and heat stress prevention strategies during taper as predictors of peaked athletic performance at the 2015 World Athletics Championship in hot conditions

ObjectivesTo investigate whether self-reported health complaints and choice of heat stress prevention strategies during the taper predicted peaking at an athletics championship in hot conditions. DesignCohort study. MethodsData on health and heat stress prevention were collected before the 2015 World Athletics Championship in Beijing, China. Peaking was defined using the athlete’s pre-competition ranking and final competition rank. Baseline and endpoint data were fitted into multiple logic regression models. ResultsTwo hundred forty-five (29%) of 841 eligible athletes participated. Both sprint/power (Odds ratio (OR) 0.33 (95% Confidence interval (CI) 0.11 to 0.94), P=0.038) and endurance/combined events (OR 0.38 (95% CI 0.14 to 1.00), P=0.049) athletes having sustained concern-causing health complaints during the taper were less likely to peak. Endurance/combined events athletes who chose pre-cooling to mitigate heat stress were less likely to peak (OR 0.35 (95% CI 0.15 to 0.80), P=0.013), while sprint/power athletes reporting a sudden-onset injury complaint during the taper displayed increased peaking (OR 4.47 (95% CI 1.28 to 15.59), P=0.019). ConclusionsHealth complaints that caused the athlete concern during the taper were predictive of failure to peak at a major athletics competition. Sprint/power athletes who experienced an acute injury symptom during the taper appeared to benefit from rest. Pre-cooling strategies seem to require further validation during real-world endurance/combined events. It appears that athletics athletes’ self-reported health should be monitored during the taper, concerns addressed, and heat stress prevention strategies individually tested before championships in hot conditions.

Dose Tapering Strategy for Heroin Abstinence among Methadone Maintenance Treatment Participants: Evidence from A Retrospective Study in Guangdong, China.

Around half of methadone maintenance treatment (MMT) participants choose the tapering phase, however, the guidelines on tapering differ between countries and only include the tapering rate. Physicians need more evidence to guide clinical practice. We aimed to explore a specific tapering strategy to improve heroin abstinence among MMT participants. We conducted a retrospective study from 2006 to 2017 at nine MMT clinics in Guangdong, China, involving 853 participants with 961 treatment episodes. We performed two-level hierarchical logistic regression models to identify tapering phase characteristics associated with heroin abstinence. Among all treatment episodes, 419 (43.6%) were heroin abstinent. Participants who started tapering after 52 weeks, had a taper start dose of less than 60 mg and a taper ratio of less than 5%/week, while a dose reduction in 75%–89% of the tapering weeks provided the highest odds of heroin abstinence. This study highlights the need for a more gradual taper than current guidelines recommend and strongly suggests the inclusion of other tapering phase characteristics. Those who start the tapering phase later, have a lower dose of methadone, with a more gradual rate of taper, and a dose reduction in 75%–89% of the tapering phase increased the odds of heroin abstinence.

Dosage reduction and discontinuation of biological disease-modifying antirheumatic drugs in patients with rheumatoid arthritis, psoriatic arthritis and axial spondyloarthritis: protocol for a pragmatic, randomised controlled trial (the BIOlogical Dose OPTimisation (BIODOPT) trial)

IntroductionThe The BIOlogical Dose OPTimisation (BIODOPT) trial is a pragmatic, multicentre, randomised controlled, open-label, parallel-group, equivalence study designed to evaluate tapering of biological disease-modifying antirheumatic drugs (bDMARDs) in patients with...

Cost-effectiveness of five different anti-tumour necrosis factor tapering strategies in rheumatoid arthritis: a modelling study

Objective: To investigate the cost-effectiveness of five different tumour necrosis factor inhibitor tapering strategies in patients with rheumatoid arthritis (RA) and stable low disease activity, using a modelling design.Method: Using Markov models based on data from the DRESS and STRASS randomized controlled trials, and the Nijmegen RA cohort, five tapering strategies for etanercept and adalimumab were tested against continuation: 1, four-step tapering (DRESS strategy); 2, five-step tapering; 3, tapering without withdrawal; 4, use of a stricter flare criterion; and 5, use of a theoretical predictor for successful tapering. We also examined how well a biomarker should be able to predict in order for strategy 5 to become cost-effective compared to the other strategies.Results: All examined tapering strategies were cost saving (range: EUR 5128 to 7873) but yielded more short-lived flares compared to continuation. The change in utilities compared to continuation was minimal and not clinically relevant (range: −0.005 to 0.007 quality-adjusted life-years). Strategy 1 was cost-effective compared to all other strategies [highest incremental net monetary benefit (iNMB)]. However, there was a large overlap in credible intervals, especially between strategies 1 and 2. Scenario analyses showed that 50% reduction of drug prices would result in the highest iNMB for strategy 2. A biomarker only becomes cost-effective when it is inexpensive and has a sensitivity and specificity of at least 84%.Conclusion: Because our study showed a comparable iNMB for tapering in four or five steps (including discontinuation), we recommend a choice between these strategies, based on shared decision making.

PF709 TAPERING AND DISCONTINUATION OF THROMBOPOIETIN RECEPTOR AGONISTS IN ITP: EXPERT CONSENSUS OPINIONS

Background:Immune thrombocytopenia (ITP) is an acquired autoimmune‐mediated disorder characterized by a platelet count &lt;100,000/μL and variable bleeding and fatigue. First‐line treatment is usually corticosteroids, which provide high response rates but are only recommended for short‐term use, due to toxicities associated with long‐term use. Thrombopoietin receptor agonists (TPO‐RAs), romiplostim and eltrombopag, are second‐line treatments that stimulate platelet production. Initially, it was thought that once a TPO‐RA was started, treatment would continue indefinitely. However, it became clear that certain patients can discontinue TPO‐RAs and maintain adequate platelet counts after stopping treatment. However, there is no clarity on how many and which patients might achieve sustained responses off treatment and which strategies are optimal to achieve these responses.Aims:To develop an expert physician‐led strategy for discontinuing TPO‐RA treatment in ITP patients.Methods:Twelve experts from the US, Brazil, Western Europe, Asia, and Australia responded to a specially designed questionnaire focusing on: selection of patients for tapering and discontinuation of TPO‐RA agents, optimal strategy to do so, monitoring approaches during and after discontinuation, and when and how to reinstate treatment if there was a relapse.Results:The respondents agreed that patients with persistent or chronic ITP receiving any dose of TPO‐RA could be considered for dose reduction in cases of stable response to treatment. Other factors should be considered, including a prior bleeding episode due to platelet count drop, hard‐to‐manage ITP or platelet count stable only on TPO‐RA treatment, patient's lifestyle, frequency and/or severity of infections that could alter counts, and time since diagnosis. Table 1 summarizes points of general panel agreement versus decisions dependent on physician preference. There was agreement on tapering rather than abrupt discontinuation; however, both faster and slower dose reductions were deemed appropriate depending on initial response to dose reduction. Half the experts would monitor platelet counts 14 days after dose reduction. The respondents were split between stable platelet counts of 50,000 or 100,000/μL, both to start tapering and to allow a second dose reduction, either immediately, or more often after a wait of 4–8 weeks. However, if the platelet count dropped to between 20,000 and 50,000/μL during tapering, treatment should be reinforced by use of the same TPO‐RA and potential addition of immunosuppression. In such a case, as platelet counts stabilize, a new tapering attempt is recommended after 2–3 months. During and after TPO‐RA discontinuation, platelet counts should be monitored regularly, and the intervals could increase in line with the duration of patient response. Initial monitoring frequency would be at 1–4‐week intervals and gradually increase to 3‐month intervals by the second half of the first year off treatment if an adequate count was maintained.Summary/Conclusion:All physicians supported the use of a tapering strategy for patients with a sustained and stable response after a minimum of several months of treatment with a TPO‐RA. Certain patients with very high platelet counts on a TPO‐RA are obvious candidates to discontinue treatment, but also those with stable counts of &gt;50,000/μL could be considered for tapering.image

Gradual tapering TNF inhibitors versus conventional synthetic DMARDs after achieving controlled disease in patients with rheumatoid arthritis: first-year results of the randomised controlled TARA study

ObjectivesThe aim of this study is to evaluate the effectiveness of two tapering strategies after achieving controlled disease in patients with rheumatoid arthritis (RA), during 1 year of follow-up.MethodsIn this...

Glucocorticoid induced adrenal insufficiency is common in steroid treated glomerular diseases - proposed strategy for screening and management

BackgroundGlucocorticoids (GCs) are frequently used to treat glomerular diseases but are associated with multiple adverse effects including hypothalamic-pituitary-adrenal axis inhibition that can lead to adrenal insufficiency (AI) on withdrawal. There is no agreed GC tapering strategy to minimise this risk.MethodsThis is a single centre retrospective study, between 2013 to 2016, of patients with glomerular disease on GC therapy for more than 3 months screened for GC induced AI with short synacthen stimulation tests (SSTs) done prior to complete GC withdrawal. We investigated the prevalence of AI, predictors, choice of screening tool and recovery.ResultsBiochemical evidence of GC induced AI was found in 57 (46.3%) patients. Total duration of GC did not differ between those with and without AI (p = 0.711). Patients with GC induced AI had a significantly lower pre-synacthen baseline cortisol as compared to patients without AI. A cut off pre-synacthen baseline cortisol of ≥223.5 nmol/l had a specificity of 100% for identifying individuals without biochemical AI. Patients with GC induced AI took a mean of 8.7 ± 4.6 months (mean ± SD) to recover. Patients with persistent AI had a significantly lower index post-synacthen cortisol measurement.ConclusionsWe demonstrate that biochemically proven GC induced AI is common in patients with glomerular diseases, is not predicted by daily dose or duration and takes a considerable time to recover. The study supports the use of morning basal cortisol testing as an appropriate means to avoid the need for SSTs in all patients and should be performed in all patients prior to consideration of GC withdrawal after 3 months duration.

Characterization of the Weekly External Load Profile of Professional Soccer Teams from Portugal and the Netherlands.

The purpose of this study was to analyze the day-to-day variance of a typical weekly external training workload of two professional soccer teams from different countries. Twenty-nine players from two professional teams from Portugal and the Netherlands participated in this study. The players’ external load was monitored for 7 weeks, by means of portable GPS devices (10 Hz, JOHAN, Noordwijk, Netherlands). Results revealed that match day -1 (MD-1), i.e. the training day before a match, had significantly (p = 0.001) less training volume (4584.50 m) than the other days. MD-5 (training five days before a match), MD-4 (four days before a match) and MD-3 (three days before a match) were the most intense (390.83, 176.90 and 247.32 m of sprinting distance, respectively) and with large volume (7062.66, 6077.30 and 6919.49 m, respectively). Interestingly, significant differences were found between clubs of different countries (p < 0.05) with the Portuguese team showing significantly higher intensity (sprinting distance) and volume (total distance) in all days with exception of MD-1 than the Dutch team. The results of this study possibly allow for the identification of different training workloads and tapering strategies between countries in relation to volume and intensity. It should be noted, however, that both clubs used a significant tapering phase in the last two days before the competition in an attempt to reduce residual fatigue accumulation.

Effect of two tapering strategies on endurance-related physiological markers in athletes from selected training centres of Ethiopia

ObjectiveWe aimed to investigate the effects of two tapering strategies on specific endurance-related performance markers in some selected athletic training centres of Ethiopia.MethodologyThirty-seven young distance runners (mean age: 20±1.97 years;...

Corticosteroid Tapering Regimens in Rheumatic Disease: A Systematic Review.

Corticosteroids have long been used to effectively treat rheumatic disorders, but adverse effects associated with extended-duration regimens generate disagreement among clinicians regarding optimal tapering strategies. The objective of this systematic review was to assess clinical outcomes of differing tapering regimens after corticosteroid monotherapy in adults with rheumatic disorders. A systematic review of Medline/PubMed, Embase, Cochrane, International Pharmaceutical Abstracts, Web of Science, Scopus, Global Index Medicus, American College of Rheumatology, gray literature, and reference lists up to June 27, 2018, was conducted by 2 authors. Randomized controlled trials, case-control studies, and prospective observational studies comparing at least 2 tapering strategies of medium- to high-dose (>7.5 mg but ≤100 mg oral prednisone equivalent daily), extended-duration (≥10 days) corticosteroids were included if they reported at least 1 efficacy and 1 adverse effect parameter. Two studies met criteria for the review, which included 62 patients. One study examined a prednisolone versus a modified release prednisone taper for giant cell arteritis and suggested 80% (n = 4) and 85.7% (n = 6) remission rates, respectively, at 26 weeks. The other study examined a methylprednisolone versus a prednisone taper for polymyalgia rheumatica and reported 100% and 89% remission rates, respectively, at 26 weeks. Adverse effects reported between the 2 studies included sleep, hyperglycemia, infection, and fractures. However, the studies were not powered to detect differences in these outcomes. There is no high-level evidence to guide tapering until discontinuation after extended courses of medium- to high-dose treatment regimens, as current guidelines rely heavily on expert opinion and small case series with a trial-and-error approach. This review supports the need for additional research to shift tapering recommendations to a more evidence-based practice.

Area-preserving scheme for efficiency enhancement in single-pass tapered free electron lasers

Efficiency enhancement of a single-pass short-wavelength high-gain tapered free electron laser (FEL) has recently been intensively studied. The goal is to sustain the growth of radiation power in the post-saturation regime. Among the various schemes, the undulator tapering is considered an effective route to achieve higher power extraction efficiency. The tapering strategy can be of constant or varying resonant phase along the undulator axis. In this paper we propose an efficiency-enhancement scheme based on preservation of the longitudinal phase space area which ensures trapping of resonant particles in the ponderomotive bucket as long as possible along the undulator axis before significant particle depletion occurs. In the meanwhile such a scheme takes advantage of the increase of the radiation field amplitude to precipitate the particle deceleration process at the middle stage of undulator tapering. We analyze such an area-preserving scheme of undulator tapering by formulating the post-saturation FEL interaction in a one-dimensional (1-D) model via introduction of the particle trapping fraction. The output performance is evaluated through numerical iteration and confirmed with 1-D particle tracking simulations. The results show that the optimal power extraction efficiency based on the proposed scheme, together with a prebunched beam, can be greatly improved within relatively short taper length compared with other schemes before radiation diffraction effect becomes significant. Besides, the undesired sideband effects are found to be effectively suppressed. For the proposed area-preserving taper scheme, we also derive an analytical approximate formula for the resonant phase as a function of undulator axis. We expect that the analysis can shed light on the aim to further enhance the power extraction efficiency in single-pass tapered FELs.

Glucocorticoid treatment in juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease of joints in childhood. Glucocorticoids are being used in JIA treatment effectively for decades. Although systemic glucocorticoid use decreased with the introduction of biologic drugs, intraarticular glucocorticoid injections(IAGI) with nonsteroidal anti-inflammatory drugs and non-biologic disease modifying anti-rheumatic drugs (DMARDs) still remain the primary treatment in JIA, especially in oligoarticular subcategory. Systemic glucocorticoids are used mainly for severe JIA-associated complications such as macrophage activation syndrome (MAS), myocarditis, pericarditis, pleuritis, peritonitis, and severe anemia; as bridging therapy while waiting for the full therapeutic effect of DMARDs; and in certain occasions for patients with severe refractory uveitis. Since glucocorticoid administration is associated with many adverse events, it is important to use glucocorticoids in an optimum way balancing the risks and benefits. The aim of this review is to summarize the current knowledge on glucocorticoid treatment in JIA. A comprehensive literature search was conducted utilizing the Cochrane Library and MEDLINE/PubMed databases. The main topics include mechanism of action, dose, duration, adverse events, vaccination during glucocorticoid treatment, the place of glucocorticoids in JIA treatment guidelines and consensus treatment plans, glucocorticoid use in JIA-associated uveitis, MAS, and IAGI. Data from the literature provide guidance on how to use glucocorticoids in JIA treatment especially for IAGI and systemic use in systemic JIA and MAS. However, there is lack of evidence and need for prospective randomized studies in most parts including the indications in different JIA subcategories, optimum dose/route of administration/duration of treatment, and tapering strategies.