INTRODUCTION: The need for biomarkers which can predict disease course and treatment response in rheumatoid arthritis (RA) is evident. We explored whether clinical and imaging responses to biologic disease modifying anti-rheumatic drug treatment (bDMARD) were associated with the individual's mediator production in explants obtained at baseline.

METHODS: RA Patients were evaluated by disease activity score 28 joint C-reactive protein (DAS 28-)), colour Doppler ultrasound (CDUS) and 3 Tesla RA magnetic resonance imaging scores (RAMRIS). Explants were established from synovectomies from a needle arthroscopic procedure prior to initiation of bDMARD. Explants were incubated with the bDMARD in question, and the productions of interleukin-6 (IL-6), monocyte chemo-attractive protein-1 (MCP-1) and macrophage inflammatory protein-1-beta (MIP-1b) were measured by multiplex immunoassays. The changes in clinical and imaging variables following a minimum of 3 months bDMARD treatment were compared to the baseline explant results. Mixed models and Spearman's rank correlations were performed. P-values below 0.05 were considered statistically significant.

RESULTS: 16 patients were included. IL-6 production in bDMARD-treated explants was significantly higher among clinical non-responders compared to responders (P = 0.04), and a lack of suppression of IL-6 by the bDMARDS correlated to a high DAS-28 (ρ = 0.57, P = 0.03), CDUS (ρ = 0.53, P = 0.04) and bone marrow oedema (ρ = 0.56, P = 0.03) at follow-up. No clinical association was found with explant MCP-1 production. MIP-1b could not be assessed due to a large number of samples below the detection limit.

CONCLUSIONS: Synovial explants appear to deliver a disease-relevant output testing which when carried out in advance of bDMARD treatment can potentially pave the road for a more patient tailored treatment approach with better treatment effects.

OBJECTIVE: Compare arthroscopic partial meniscectomy to a true sham intervention.

METHODS: Sham-controlled superiority trial performed in three county hospitals in Denmark comparing arthroscopic partial meniscectomy to skin incisions only in patients aged 35-55 years with persistent knee pain and an MRI-confirmed medial meniscus lesion. A computer-generated table of random numbers generated two comparison groups. Participants and outcome assessors were blinded to group allocation. Exclusions were locking knees, high-energy trauma or severe osteoarthritis. Outcomes were collected at baseline, 3 and 24 months. We hypothesised no difference between groups. The primary outcome was the between-group difference in change from baseline to 2 years in the mean score across all five normalised Knee injury and Osteoarthritis Outcome Score (KOOS) subscales (KOOS5).

RESULTS: Forty-four patients (of the estimated 72) underwent randomisation; 22 in each group. Sixteen participants (36%) were non-blinded and eight participants (36%) from the sham group crossed over to the surgery group prior to the 2-year follow-up. At 2 years, both groups reported clinically relevant improvements (surgery 21.8, skin incisions only 13.6), the mean difference between groups was 8.2 in favour of surgery, which is slightly less than the cut-off of 10 prespecified to represent a clinically relevant difference; judged by the 95% CI (-3.4 to 19.8), a possibility of clinically relevant difference could not be excluded. In total, nine participants experienced 11 adverse events; six in the surgery group and three in the skin-incisions-only group.

CONCLUSION: We found greater improvement from arthroscopic partial meniscectomy compared with skin incisions only at 2 years, with the statistical uncertainty of the between-group difference including what could be considered clinically relevant. Because of the study being underpowered, nearly half in the sham group being non-blinded and one-third crossing over to surgery, the results cannot be generalised to the greater patient population.

TRIAL REGISTRATION NUMBER: NCT01264991.

OBJECTIVES: Large-scale observational cohorts may be used to study the effectiveness and rare side effects of biological disease-modifying anti-rheumatic drugs (bDMARDs) in ankylosing spondylitis (AS), but may be hampered by differences in baseline characteristics and disease activity across countries. We aimed to explore the research infrastructure in the five Nordic countries regarding bDMARD treatment in AS.

METHOD: This observational cohort study was based on data from biological registries in Denmark (DANBIO), Sweden (SRQ/ARTIS), Finland (ROB-FIN), Norway (NOR-DMARD), and Iceland (ICEBIO). Data were collected for the years 2010-2016. Registry coverage, registry inventory (patient characteristics, disease activity measures), and national guidelines for bDMARD prescription in AS were described per country. Incident (first line) and prevalent bDMARD use per capita, country, and year were calculated. In AS patients who started first line bDMARDs during 2010-2016 (n = 4392), baseline characteristics and disease activity measures were retrieved.

RESULTS: Registry coverage of bDMARD-treated patients ranged from 60% to 95%. All registries included extensive prospectively collected data at patient level. Guidelines regarding choice of first line drug and prescription patterns varied across countries. During the period 2010-2016 prevalent bDMARD use increased (p < 0.001), whereas incident use tended to decrease (p for trend < 0.004), with large national variations (e.g. 2016 incidence: Iceland 10.7/100 000, Finland 1.7/100 000). Baseline characteristics were similar regarding C-reactive protein, but differed for other variables, including the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) (range 3.5-6.3) and Ankylosing Spondylitis Disease Activity Score (ASDAS) (2.7-3.8) (both p < 0.0001).

CONCLUSION: Collaboration across the five Nordic biological registries regarding bDMARD use in AS is feasible but national differences in coverage, prescription patterns, and patient characteristics must be taken into account depending on the scientific question.

OBJECTIVE: To report mortality and disability due to rheumatoid arthritis (RA) in the Nordic region (Denmark, Finland, Greenland, Iceland, Norway, and Sweden) using data from the Global Burden of Disease Study (GBD) 2015.

METHOD: Using the results of GBD 2015, we present rates and trends in prevalence, mortality, years of life lost, years lived with disability (YLD), and disability-adjusted life-years (DALYs) of RA in the Nordic region during 1990-2015.

RESULTS: In 2015, the age-standardized prevalence of RA was higher in the Nordic region than the global level (0.44%, 95% uncertainty interval 0.40-0.48%, vs 0.35%, 0.32-0.38%). For women (men), DALYs increased by 2.4% (12.9%), from 29 263 (10 909) in 1990 to 29 966 (12 311) in 2015. The burden of RA as a proportion of total DALYs in women (men) increased from 0.90% (0.29%) in 1990 to 0.94% (0.36%) in 2015. Age-standardized DALY rates declined in all countries except Denmark and Greenland between 1990 and 2015. Of 315 conditions studied, RA was ranked as the 16th (37th) leading cause of YLD in women (men) in the region. Of 195 countries studied, Greenland, Finland, Denmark, Norway, Sweden, and Iceland had the 7th, 11th, 28th, 38th, 48th, and 78th highest age-standardized YLD rates for RA, respectively.

CONCLUSIONS: The prevalence of RA in the Nordic region is higher than the global average. Current trends in population growth and ageing suggest a potential increase in RA burden in the coming decades in the region that should be considered in healthcare resources allocation.

INTRODUCTION: Lumbar spinal stenosis is a common cause of low back and leg pain in the elderly and affects both physical activity and quality of life. First-line treatments are non-surgical options but if unsuccessful, surgery is advocated. The literature is not clear as to the outcome of surgery compared with non-surgical treatment, and the optimal time for surgery is not explicit. This observational study is designed to investigate the course of treatment, compare effectiveness of surgical and non-surgical management in patients with lumbar spinal stenosis and identify prognostic factors for outcome in the context of current clinical practice.

MATERIALS AND ANALYSIS: Prospectively registered data on treatment, outcome and patient characteristics are collected from nationwide registers on health and social issues, a clinical registry of people with chronic back pain and hospital medical records. Primary outcome is change in physical function measured by the Zurich Claudication Questionnaire. Secondary outcomes are changes in symptom severity, pain-related function, health-related quality of life and general self-efficacy. Outcomes are assessed at baseline and 6 and 12 months. Outcomes at 12 months will be compared for patients who undergo surgery for lumbar spinal stenosis and patients managed non-surgically, using different analytical approaches. Prespecified prognostic factors of interest at baseline include treatment allocation, back and leg pain intensity, comorbidity, duration of symptoms, pretreatment function, self-rated health, income, general self-efficacy and MRI-graded severity of central stenosis.

ETHICS AND DISSEMINATION: The study has been evaluated by the Regional Committees on Health Research for Southern Denmark (S-20172000-200) and notified to the Danish Data Protection Agency (18/22336). All participants provide consent. Findings will be disseminated in peer-reviewed publications and presented at national and international conferences according to the Strengthening the Reporting of Observational Studies in Epidemiology and Prognosis Research Strategy statements. Potential sources of bias will be addressed using Risk of Bias in Non-randomised Studies of Interventions.

TRIAL REGISTRATION NUMBER: NCT03548441; Pre-results.

Studies have suggested that vitamin D status at birth may be associated with a range of neonatal outcomes. The aim of this study was to assess the association between neonatal 25-hydroxyvitamin D3 (25(OH)D3) concentration and gestational age, birth weight, Ponderal Index and size for gestational age. Neonatal capillary blood stored as dried blood spots was used to assess 25(OH)D3 concentrations among 2686 subjects selected from a random population sub-sample of individuals, born in Denmark from 1 May 1981 to 31 December 2002. There was an inverse association between 25(OH)D3 concentration and gestational age at birth of -0·006 (95 % CI -0·009, -0·003, P<0·001) weeks of gestation per 1 nmol/l increase in 25(OH)D3 concentration. An inverted U-shaped association between 25(OH)D3 and birth weight and Ponderal Index (P=0·04) was found, but no association with size for gestational age was shown. This study suggests that neonatal 25(OH)D3 concentration is associated with anthropometric measures at birth known to be correlated with many subsequent health outcomes such as obesity and type 2 diabetes.

In the original version of this article the first name of the co-author was incorrectly spelled as "Khaled A. Alnaqbi". The correct spelling should have been "Khalid A. Alnaqbi". This is now presented correctly in this article.

BACKGROUND: Healthy dietary and physical activity behaviours are established early in life where children learn by observing their parents. Therefore, parents can act as role models and influence their children toward a healthier lifestyle. Besides a strong association between parental and child health behaviours, parents also influence their children's health behaviours through socio-cognitive processes, where perceived self-efficacy is the central component. The objective was to examine if parental self-efficacy among Swedish mothers was associated with their four-year-old children's dietary and physical activity behaviours.

METHODS: This cross-sectional study was based on information from control participants that took part in the Swedish primary prevention trial of childhood obesity (PRIMROSE) (n = 420 mother-child pairs). Linear regression models were used to examine the associations between parental self-efficacy (Parental Self-Efficacy for Promoting Healthy Physical Activity and Dietary Behaviours in Children Scale) and children's dietary intake (parent reported) and levels of physical activity (accelerometer) with adjustments for potential confounders.

RESULTS: Mothers' efficacy beliefs in promoting healthy dietary or physical activity behaviours in their children were associated with a slightly higher consumption of fruit and vegetables among their children (β: 0.03 [95%CI: 0.01; 0.04] P < 0.001) and slightly higher levels of moderate-to-vigorous activity (β: 0.43 [95%CI: 0.05; 0.81] P = 0.03). Mothers' belief in their ability to limit unhealthy dietary and physical activity behaviours was inversely associated with children's intake of unhealthy snacks (β: -0.06 [95%CI: -0.10; -0.02] P < 0.01).

CONCLUSION: Our cross-sectional study suggests weak positive correlations between maternal self-efficacy and healthy dietary and physical activity behaviours, and weak inverse associations between maternal self-efficacy and unhealthy dietary and physical activity behaviours among their children.