A Federated Database for Obesity Research: An IMI-SOPHIA Study.

Obesity is considered by many as a lifestyle choice rather than a chronic progressive disease. The Innovative Medicines Initiative (IMI) SOPHIA (Stratification of Obesity Phenotypes to Optimize Future Obesity Therapy) project is part of a momentum shift aiming to provide better tools for the stratification of people with obesity according to disease risk and treatment response. One of the challenges to achieving these goals is that many clinical cohorts are siloed, limiting the potential of combined data for biomarker discovery. In SOPHIA, we have addressed this challenge by setting up a federated database building on open-source DataSHIELD technology. The database currently federates 16 cohorts that are accessible via a central gateway. The database is multi-modal, including research studies, clinical trials, and routine health data, and is accessed using the R statistical programming environment where statistical and machine learning analyses can be performed at a distance without any disclosure of patient-level data. We demonstrate the use of the database by providing a proof-of-concept analysis, performing a federated linear model of BMI and systolic blood pressure, pooling all data from 16 studies virtually without any analyst seeing individual patient-level data. This analysis provided similar point estimates compared to a meta-analysis of the 16 individual studies. Our approach provides a benchmark for reproducible, safe federated analyses across multiple study types provided by multiple stakeholders.

Long-term efficacy of low-dose radiation therapy on symptoms in patients with knee and hand osteoarthritis: follow-up results of two parallel randomised, sham-controlled trials.

BACKGROUND: Low-dose radiation therapy is commonly used as treatment for benign diseases, including osteoarthritis, in some countries (eg, Germany). We have previously presented our 3-month follow-up results of two randomised sham-controlled trials, in which no substantial effects of low-dose radiation therapy on clinical outcomes were seen in patients with knee and hand osteoarthritis. Here we report the 6-month and 12-month results of these studies. METHODS: In one randomised sham-controlled trial, patients with knee osteoarthrosis were recruited, and in the other trial patients with hand osteoarthritis were recruited. All patients were recruited from the department of rheumatology of Sint Maartenskliniek (Nijmegen, The Netherlands) and the trials were undertaken in parallel. Patients were eligible if they had knee or hand osteoarthritis according to American College of Rheumatology (ACR) criteria, had a pain score of 5 or more on a 0-10 scale for at least 15 of the past 30 days, and did not meet 2011 modified ACR criteria for fibromyalgia. In each study, patients were randomly assigned (1:1), stratified by pain score (<8 vs ≥8) using a computer-generated randomisation list and stratified block randomisation, to low-dose radiation therapy (six fractions of 1 Gy low-dose radiation therapy in 2 weeks) or sham (six sessions with 0 Gy of radiation therapy in 2 weeks) intervention. Patients and researchers involved in patient contact or assessments were masked to group allocation, whereas the radiotherapy technologist who did the treatment was unmasked. Patients completed questionnaires (numeric rating scale of patients' global assessment and validated measures for pain and functioning) at baseline and at 1, 2, 3, 6, and 12 months after starting treatment. The primary outcome was the proportion of participants who responded according to the Outcome Measures in Rheumatology Osteoarthritis Research Society International responder criteria at 3 months, which has been reported previously. Here we report the proportion of participants who responded at 6 months and 12 months, and other clinical outcomes of pain, functioning, and patients' global assessment of their symptoms. We used logistic and linear mixed-models analyses to assess differences in number of responders and continuous outcomes. Safety was assessed in all participants who received at least one fraction of low-dose radiation or sham treatment. This study is registered with the Netherlands Trial Registry, NTR4574, and is closed to accrual. FINDINGS: Between Oct 14, 2015, and May 3, 2017, 213 patients were screened for inclusion for the knee osteoarthritis study, of whom 55 were eligible and randomly assigned to low-dose radiation therapy (n=27) or sham intervention (n=28). In parallel, for the hand osteoarthritis study, 368 patients were screened and 56 were randomly assigned low-dose radiation (n=28) or sham intervention (n=28). Some minor imbalances in baseline demographic characteristics in terms of sex and age were seen in both the knee and hand cohorts. In the knee osteoarthritis cohort, 48 patients were assessible at 6 months and 50 were assessible at 12 months, and in the hand osteoarthritis cohort 52 patients were assessible at 6 and 12 months. We found no significant differences at 6 or 12 months in the proportion of participants who had a response for both groups. In the knee osteoarthritis group, at 6 months, the number of responders was nine (41%) of 22 patients who received low-dose radiation therapy versus nine (35%) of 26 patients who received the sham intervention (difference in proportion 7% [95% CI -20 to 33]; odds ratio [OR] 1·34 [95% CI 0·41 to 4·42]); and at 12 months, 13 (52%) of 25 patients versus 11 (44%) of 25 patients responded (difference in proportion 8% [-19 to 35]; OR 1·41 [0·45 to 4·48]). In the hand osteoarthritis group, at 6 months, the number of responders was seven (28%) of 25 patients who received low-dose radiation therapy versus 11 (31%) of 27 patients who received the sham intervention (difference in proportion 12% [-38 to 13]; OR 0·57 [0·18 to 1·81]); and at 12 months, eight (31%) of 26 patients versus seven (27%) of 26 patients responded (difference in proportion 4% [-20 to 29]; OR 1·23 [0·37 to 4·12]). We did not find any difference between groups in other clinical outcomes at 6 or 12 months. Three participants with knee osteoarthritis in the sham intervention group and two participants with hand osteoarthritis in the low-dose radiation therapy group had serious adverse effects, none of which were considered to be related to the intervention. INTERPRETATION: We did not find evidence of a delayed effect of low-dose radiation therapy for patients with knee and hand osteoarthritis. Our placebo-controlled results suggest that the large effects of low-dose radiation therapy reported in clinical practice and observational studies can probably be explained by a regression to the mean effect and response to placebo. FUNDING: Dutch Arthritis Foundation and Stichting Landelijk Katholiek Reumacentrum, Netherlands.

Effectiveness of low-dose radiation therapy on symptoms in patients with knee osteoarthritis: a randomised, double-blinded, sham-controlled trial.

OBJECTIVES: Low-dose radiation therapy (LDRT) for benign disorders such as knee osteoarthritis (OA) is widely used in some parts of the world, despite absence of controlled studies. We evaluated the effect of LDRT on symptoms and inflammation in patients with knee OA. METHODS: In this randomised, double-blinded, sham-controlled clinical trial (RCT), we recruited patients with knee OA (clinical ACR criteria) in the Netherlands, aged ≥50 years, pain score ≥5/10 and non-responding to analgesics and exercise therapy. Patients were randomised 1:1 to receive LDRT (1 Gray per fraction) or sham intervention six times in 2 weeks, stratified by pain (<8 versus ≥8/10). Primary outcome was the proportion of OMERACT-OARSI responders, 3 months postintervention. Secondary outcomes included pain, function and inflammatory signs assessed by ultrasound, MRI and serum inflammatory markers. RESULTS: We randomly assigned 55 patients: 27 (49%) to LDRT and 28 (51%) to sham. At 3 months postintervention, 12/27 patients (44%; 95% CI 26% to 63%) in the LDRT vs 12/28 patients (43%; 95% CI 25% to 61%) in the sham group responded; difference 2% (95% CI 25% to 28%), OR adjusted for the stratifying variable was 1.1 (95% CI 0.4 to 3.2). Also, for clinical and any of the inflammatory signs, no differences were observed. CONCLUSIONS: We found no substantial beneficial effect on symptoms and inflammatory signs of LDRT in patients knee OA, compared with sham treatment. Therefore, based on this RCT and the absence of other high-quality evidence, we advise against the use of LDRT as treatment for knee OA. TRIAL REGISTRATION NUMBER: NTR4574.

No effect of additional screw fixation of a cementless, all-polyethylene press-fit socket on migration, wear, and clinical outcome.

Background and purpose - Additional screw fixation of the all-polyethylene press-fit RM cup (Mathys) has no additional value for migration, in the first 2 years after surgery. However, the medium-term and long-term effects of screw fixation remain unclear. We therefore evaluated the influence of screw fixation on migration, wear, and clinical outcome at 6.5 years using radiostereometric analysis (RSA). Patients and methods - This study involved prolonged follow-up from a previous randomized controlled trial (RCT). We analyzed RSA radiographs taken at baseline and at 1-, 2-, and 6.5-year follow-up. Cup migration and wear were assessed using model-based RSA software. Wear was calculated as translation of the femoral head model in relation to the cup model. Total translation, rotation, and wear were calculated mathematically from results of the orthogonal components. Results - 27 patients (15 with screw fixation and 12 without) were available for follow-up at 6.5 (5.6-7.2) years. Total translation (0.50 mm vs. 0.56 mm) and rotation (1.01 degrees vs. 1.33 degrees) of the cup was low, and was not significantly different between the 2 groups. Wear increased over time, and was similar between the 2 groups (0.58 mm vs. 0.53 mm). Wear rate (0.08 mm/year vs. 0.09 mm/year) and clinical outcomes were also similar. Interpretation - Our results indicate that additional screw fixation of all-polyethylene press-fit RM cups has no additional value regarding medium-term migration and clinical outcome. The wear rate was low in both groups.

Disease activity guided dose reduction and withdrawal of adalimumab or etanercept compared with usual care in rheumatoid arthritis: open label, randomised controlled, non-inferiority trial.

OBJECTIVE: To evaluate whether a disease activity guided strategy of dose reduction of two tumour necrosis factor (TNF) inhibitors, adalimumab or etanercept, is non-inferior in maintaining disease control in patients with rheumatoid arthritis compared with usual care. DESIGN: Randomised controlled, open label, non-inferiority strategy trial. SETTING: Two rheumatology outpatient clinics in the Netherlands, from December 2011 to May 2014. PARTICIPANTS: 180 patients with rheumatoid arthritis and low disease activity using adalimumab or etanercept; 121 allocated to the dose reduction strategy, 59 to usual care. INTERVENTIONS: Disease activity guided dose reduction (advice to stepwise increase the injection interval every three months, until flare of disease activity or discontinuation) or usual care (no dose reduction advice). Flare was defined as increase in DAS28-CRP (a composite score measuring disease activity) greater than 1.2, or increase greater than 0.6 and current score of at least 3.2. In the case of flare, TNF inhibitor use was restarted or escalated. MAIN OUTCOME MEASURES: Difference in proportions of patients with major flare (DAS28-CRP based flare longer than three months) between the two groups at 18 months, compared against a non-inferiority margin of 20%. Secondary outcomes included TNF inhibitor use at study end, functioning, quality of life, radiographic progression, and adverse events. RESULTS: Dose reduction of adalimumab or etanercept was non-inferior to usual care (proportion of patients with major flare at 18 months, 12% v 10%; difference 2%, 95% confidence interval -12% to 12%). In the dose reduction group, TNF inhibitor use could successfully be stopped in 20% (95% confidence interval 13% to 28%), the injection interval successfully increased in 43% (34% to 53%), but no dose reduction was possible in 37% (28% to 46%). Functional status, quality of life, relevant radiographic progression, and adverse events did not differ between the groups, although short lived flares (73% v 27%) and minimal radiographic progression (32% v 15%) were more frequent in dose reduction than usual care. CONCLUSIONS: A disease activity guided, dose reduction strategy of adalimumab or etanercept to treat rheumatoid arthritis is non-inferior to usual care with regard to major flaring, while resulting in the successful dose reduction or stopping in two thirds of patients.Trial registration Dutch trial register (www.trialregister.nl), NTR 3216.

Gait and gait-related activities of daily living after total hip arthroplasty: a systematic review.

BACKGROUND: Differences in the performance of gait and gait-related activities of daily living are known to persist after total hip arthroplasty compared to healthy controls, but the specific underlying deficits (spatiotemporal, kinematics and kinetics) are not completely understood. This review aimed to map the differences between patients and controls, and between the operated and non-operated limbs during various activities of daily living. METHODS: A computerized search with broad search terms was performed in the MEDLINE database. Primary inclusion criteria were: primary osteoarthritis as indication, comparison with healthy controls or comparison between the operated and the non-operated limbs, and follow-up period at least six months after surgery. FINDINGS: The literature search yielded 2177 citations, of which 35 articles were included. Compared to controls, reductions were identified in the operated hip in sagittal range of motion, peak extension, sagittal power generation, abduction moment and external rotation moment. During stair ascent, these reductions did not become more apparent, although deficits in hip kinetics in all three planes were found. Walking speed and step length were reduced compared to controls at longer-term follow-up, but not at short-term follow-up. INTERPRETATION: The hip abduction moment deficit was present both in level walking and in stair ascent in total hip arthroplasty patients compared to controls. Reduced sagittal hip power generation and external rotation moment were also found, of which the clinical relevance remains to be established. Due to a low number of studies, many of the longer-term effects of THA on gait and gait-related ADL are not yet accurately known.