Development of a Multimodal, Physiotherapist-Led, Vocational Intervention for People with Inflammatory Arthritis and Reduced Work Ability: A Mixed-Methods Design Study

PURPOSE

Work ability of people with rheumatoid arthritis (RA) and axial spondyloarthritis (axSpA) is reduced, but underexamined as a clinical treatment target. The evidence on vocational interventions indicates that delivery by a single healthcare professional (HCP) may be beneficial. Physiotherapist (PT)-led interventions have potential because PTs are most commonly consulted by RA/axSpA patients in the Netherlands. The aim was to develop a PT-led, vocational intervention for people with RA/axSpA and reduced work ability.

METHODS

Mixed-methods design based on the Medical Research Council (MRC) framework for developing and evaluating complex interventions, combining a rapid literature review and six group meetings with: patient representatives (n = 6 and 10), PTs (n = 12), (occupational) HCPs (n = 9), researchers (n = 6) and a feasibility test in patients (n = 4) and PTs (n = 4).

RESULTS

An intervention was developed and evaluated. Patient representatives emphasized the importance of PTs' expertise in rheumatic diseases and work ability. The potential for PTs to support patients was confirmed by PTs and HCPs. The feasibility test confirmed adequate feasibility and underlined necessity of training PTs in delivery. The final intervention comprised work-focussed modalities integrated into conventional PT treatment (10-21 sessions over 12 months), including a personalized work-roadmap to guide patients to other professionals, exercise therapy, patient education and optional modalities.

CONCLUSION

A mixed-methods design with stakeholder involvement produced a PT-led, vocational intervention for people with RA/axSpA and reduced work ability, tested for feasibility and ready for effectiveness evaluation.

Effectiveness and cost-effectiveness of a multimodal, physiotherapist-led, vocational intervention in people with inflammatory arthritis: study protocol of the Physiotherapy WORKs trial

BACKGROUND

Although reduced work ability is a substantial problem among people with inflammatory arthritis (IA), work ability is an underexposed area in clinical practice. Evidence on vocational interventions in IA is limited, but favourable results of delivery by a physiotherapist (PT) warrant the need for further research. Therefore, we aim to evaluate the (cost-)effectiveness of a multimodal, PT-led, vocational intervention in (self-)employed people with IA compared to usual care.

METHODS

This randomized controlled trial will include 140 people with rheumatoid arthritis (RA) or axial spondyloarthritis (axSpA) who are (self-)employed and have reduced work ability (Work Ability Index - Single Item Scale (WAS) ≤ 7/10) and/or RA/axSpA related sick leave (≤ 6 months). Participants will be randomized 1:1 to the intervention or control condition (usual care). The intervention, delivered by primary care PTs, will be personalized to each patient, consisting of 10 to 21 sessions over 12 months. The intervention will be multimodal, comprising of 1) exercise therapy and a physical activity plan, 2) education/self-management support, 3) work-roadmap to guide participants in finding relevant other care, with optionally 4) online self-management course and 5) workplace examination. Assessments will be performed at baseline and after 3, 6, and 12 months. The primary outcome measure of effectiveness is work ability, as measured with the WAS at 12 months. For the cost-effectiveness analysis, the EuroQol (EQ-5D-5L), self-reported healthcare use, sick leave and productivity while at work will be used to estimate the trial based cost-utility from a societal perspective. A process evaluation, including assessments of adherence and treatment fidelity, will be undertaken using the registrations of the PTs and semi-structured interviews at 12 months follow-up in a random sample of the intervention group.

DISCUSSION

The results of this study will provide insights in the (cost-)effectiveness of a multimodal, PT-led, vocational intervention in people with IA and a reduced work ability.

TRIAL REGISTRATION

This study is registered in the International Clinical Trial Registry Platform (ICTRP) under number NL9343.

Development and internal validation of a machine learning prediction model for low back pain non-recovery in patients with an acute episode consulting a physiotherapist in primary care

Background

While low back pain occurs in nearly everybody and is the leading cause of disability worldwide, we lack instruments to accurately predict persistence of acute low back pain. We aimed to develop and internally validate a machine learning model predicting non-recovery in acute low back pain and to compare this with current practice and ‘traditional’ prediction modeling.

Methods

Prognostic cohort-study in primary care physiotherapy. Patients (n = 247) with acute low back pain (≤ one month) consulting physiotherapists were included. Candidate predictors were assessed by questionnaire at baseline and (to capture early recovery) after one and two weeks. Primary outcome was non-recovery after three months, defined as at least mild pain (Numeric Rating Scale > 2/10). Machine learning models to predict non-recovery were developed and internally validated, and compared with two current practices in physiotherapy (STarT Back tool and physiotherapists’ expectation) and ‘traditional’ logistic regression analysis.

Results

Forty-seven percent of the participants did not recover at three months. The best performing machine learning model showed acceptable predictive performance (area under the curve: 0.66). Although this was no better than a’traditional’ logistic regression model, it outperformed current practice.

Conclusions

We developed two prognostic models containing partially different predictors, with acceptable performance for predicting (non-)recovery in patients with acute LBP, which was better than current practice. Our prognostic models have the potential of integration in a clinical decision support system to facilitate data-driven, personalized treatment of acute low back pain, but needs external validation first.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05718-7.

Patients' and clinicians' experiences with stratified exercise therapy in knee osteoarthritis: a qualitative study

Background

We have developed a model of stratified exercise therapy that distinguishes three knee osteoarthritis (OA) subgroups (‘high muscle strength subgroup’, ‘low muscle strength subgroup’, ‘obesity subgroup’), which are provided subgroup-specific exercise therapy (supplemented by a dietary intervention for the ‘obesity subgroup’). In a large clinical trial, this intervention was found to be no more effective than usual exercise therapy. The present qualitative study aimed to explore experiences from users of this intervention, in order to identify possible improvements.

Methods

Qualitative research design embedded within a cluster randomized controlled trial in a primary care setting. A random sample from the experimental arm (i.e., 15 patients, 11 physiotherapists and 5 dieticians) was interviewed on their experiences with receiving or applying the intervention. Qualitative data from these semi-structured interviews were thematically analysed.

Results

We identified four themes: one theme regarding the positive experiences with the intervention and three themes regarding perceived barriers. Although users from all 3 perspectives (patients, physiotherapists and dieticians) generally perceived the intervention as having added value, we also identified several barriers, especially for the ‘obesity subgroup’. In this ‘obesity subgroup’, physiotherapists perceived obesity as difficult to address, dieticians reported that more consultations are needed to reach sustainable weight loss and both physiotherapists and dieticians reported a lack of interprofessional collaboration. In the ‘high muscle strength subgroup’, the low number of supervised sessions was perceived as a barrier by some patients and physiotherapists, but as a facilitator by others. A final theme addressed barriers to knee OA treatment in general, with lack of motivation as the most prominent of these.

Conclusion

Our qualitative study revealed a number of barriers to effective application of the stratified exercise therapy, especially for the ‘obesity subgroup’. Based on these barriers, the intervention and its implementation could possibly be improved. Moreover, these barriers are likely to account at least partly for the lack of superiority over usual exercise therapy.

Trial registration

The Netherlands National Trial Register (NTR): NL7463 (date of registration: 8 January 2019).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05496-2.

OP0188 CLINICAL EFFECTIVENESS OF STRATIFIED EXERCISE THERAPY COMPARED TO USUAL EXERCISE THERAPY IN PATIENTS WITH KNEE OSTEOARTHRITIS: A CLUSTER RANDOMIZED CONTROLLED TRIAL (OCTOPuS-STUDY)

Background

There is strong, high-quality evidence for the effectiveness of exercise therapy in people with knee osteoarthritis (OA).1 However, although effective, the average effect size is only moderate (approximately 0.5).1 This may be attributed to the current ‘one-size-fits-all’ exercise approach, while a stratified approach may yield superior clinical and economic outcomes. We are the first to test a model of stratified exercise therapy in patients in knee OA. This model was based on 3 previously identified subgroups2 that are aligned with well-accepted OA phenotypes3, namely a ‘low muscle strength subgroup’ (‘age-induced phenotype’), ‘high muscle strength subgroup’ (‘post-traumatic phenotype’) and ‘obesity subgroup’ (‘metabolic phenotype’). For each subgroup, a subgroup-specific exercise therapy intervention was developed and pilot-tested4, which was supplemented by a dietary intervention for the ‘obesity subgroup’.

Objectives

The OCTOPuS-trial aimed to determine the effectiveness of stratified exercise therapy in reducing knee pain and improving physical function, compared to usual, ‘non-stratified’ exercise therapy, in patients with knee OA.

Methods

We conducted a pragmatic cluster randomized controlled trial in a primary care setting in 335 people with knee osteoarthritis: 153 in the experimental arm and 182 in the control arm. Physiotherapy practices were randomized into the experimental arm providing the model of stratified exercise therapy supplemented by a dietary intervention from a dietician for the ‘obesity subgroup’ or the control arm proving usual, ‘non-stratified’ exercise therapy. Primary outcomes were knee pain severity (NRS pain, 0-10) and physical function (KOOS subscale daily living, 0-100). Measurements were performed at baseline, and 3- (primary endpoint), 6-, and 12-months follow-up. Intention-to-treat, multilevel, regression analysis was performed.

Results

We found statistically non-significant differences in knee pain (mean difference (95% confidence interval): 0.19 (-0.31, 0.69)) and physical function (-0.40 (-3.91, 3.12)) at 3-months follow-up, with within-group effect sizes ranging between 0.5 and 0.7. Non-significant differences were also found for all other time points and for nearly all secondary outcome measures. Moreover, effects of experimental and control intervention were similar in each of the 3 subgroup separately.

Conclusion

This trial demonstrated no added value with respect to clinical outcomes of our model of stratified exercise therapy compared to usual exercise therapy. This could be attributed to the experimental arm therapists facing difficulty in effectively applying the model (especially in the ‘obesity subgroup’) and to elements of the model possibly being applied in the control arm.

References

[1]Fransen M et al. Exercise for osteoarthritis of the knee. Cochrane Database Syst Rev. 2015 Jan 9;1:CD004376.

[2]Knoop J et al. Identification of phenotypes with different clinical outcomes in knee osteoarthritis: data from the Osteoarthritis Initiative. Arthritis Care Res (Hoboken). 2011;63(11):1535-1542.

[3]Bijlsma JW et al. Osteoarthritis: an update with relevance for clinical practice. Lancet. 2011; Jun 18;377(9783):2115-26.

[4]Knoop J et al. Is a model of stratified exercise therapy by physical therapists in primary care feasible in patients with knee osteoarthritis? A mixed methods study. Physiotherapy. 2019.

Disclosure of Interests

None declared

OP0201-PARE DEVELOPMENT THROUGH CO-CREATION OF A PERSONALIZED, MULTIMODAL, PHYSIOTHERAPIST-LED, WORK-ORIENTED INTERVENTION TO INCREASE WORK ABILITY IN WORKING PEOPLE WITH RHEUMATOID ARTHRITIS OR AXIAL SPONDYLOARTHRITIS

Background

Although work ability is considered a key element of quality of life for working people, work is underexposed in current treatment in people with rheumatoid arthritis (RA) or axial spondyloarthritis (axSpA). Most people with RA or axSpA attend a physiotherapist (PT). Physiotherapy can effectively improve physical fitness, which is associated with work ability. Therefore, PTs might play an important role in optimizing work ability of people with RA or axSpA.

Objectives

Developing a personalized, multimodal, PT-led, work-oriented intervention for working people with RA or axSpA who have a reduced work ability, through a co-creation process.

Methods

A systematic co-creation process with all relevant stakeholders was conducted following the Medical Research Council (MRC)-framework for complex interventions (see Figure 1). In step 1, all relevant clinical guidelines and treatment protocols were assessed. Based on the results of this assessment, a draft version of the intervention was developed, consisting of mandatory (i.e., work-oriented intake, patient education, exercise therapy, referral-roadmap of work-related professionals) and optional treatment modalities (i.e., workplace-intervention, self-management course). In step 2, focus groups with people with RA/axSpA, PTs and occupational/rheumatology experts were organized and qualitatively analysed. In the focus groups, barriers and facilitators of work-oriented treatments and necessary adaptations to the draft intervention were discussed. In step 3, a pre-test was performed to test the feasibility of the intervention in a primary physiotherapy setting, which was evaluated in the group of PTs participating in the pre-test in step 4. Finally, in step 5, a final focus group with researchers in this field was held to discuss the findings from previous steps in this co-creation process and to agree on necessary adaptations in the final intervention.

Figure 1.

Process of systematic development of co-created, work-oriented physiotherapist-led intervention following the MRC-framework.

Results

After developing the draft intervention, we conducted two focus groups with people with RA/axSpA (n=16; 4 with RA, 12 with axSpA), one focus group with PTs (n=12) and one focus group with occupational/rheumatology experts (n=9; 2 rheumatologists, 2 nurse specialists, 1 physiatrists, 1 physician assistant, 1 nurse practitioner, 1 labour expert and 1 occupational therapist). People with RA or axSpA emphasized 3 aspects: i) PTs should have adequate expertise in RA/axSpA, ii) high potential for a role of ‘buddy’ by PTs to support them in work-related problems, and iii) most PTs currently lack adequate expertise on work-related problems. PTs and experts underlined the importance of extensive training of PTs on work-related laws and regulations and adequate (work-related) interprofessional collaboration. After revision of the draft intervention, the intervention was tested for feasibility by three PTs and three working people (2 with RA, 1 with axSpA), who indicated that the intervention was feasible and that the developed intervention facilitated PTs to support people in optimizing their work ability. However, adequate training on providing this intervention was recognized to be essential. In a final focus group with researchers (n=6), consensus was reached on minor adjustments to the intervention that were based on findings from previous steps.

Conclusion

Through a systematic co-creation process based on the MRC-framework, we have been able to develop a personalized, multimodal, PT-led, work-oriented intervention for working people with RA or axSpA and a reduced work ability. The (cost-)effectiveness of this intervention is currently being tested in a large trial (Physiotherapy WORKs study).

Acknowledgements

This study is funded by the Dutch Arthritis Society (ReumaNederland) and the Scientific College of Physical Therapy (WCF) of the Royal Dutch Society for Physical Therapy (KNGF). This study is registered in the Netherlands Trial Register under number NL9343.

Disclosure of Interests

None declared

How does hip osteoarthritis differ from knee osteoarthritis?

Hip and knee osteoarthritis (OA) are leading causes of global disability. Most research to date has focused on the knee, with results often extrapolated to the hip, and this extends to treatment recommendations in clinical guidelines. Extrapolating results from research on knee OA may limit our understanding of disease characteristics specific to hip OA, thereby constraining development and implementation of effective treatments. This review highlights differences between hip and knee OA with respect to prevalence, prognosis, epigenetics, pathophysiology, anatomical and biomechanical factors, clinical presentation, pain and non-surgical treatment recommendations and management.

POS0157-HPR CONSTRUCT VALIDITY OF THE OCTOPUS STRATIFICATION ALGORITHM FOR ALLOCATING PATIENTS WITH KNEE OSTEOARTHRITIS INTO CLINICALLY RELEVANT SUBGROUPS

Background:

We recently developed a model of stratified exercise therapy [1], consisting of (i) a stratification algorithm allocating patients with knee osteoarthritis (OA) into clinically relevant subgroups, and (ii) subgroup-specific exercise therapy. More specifically, in our model we distinguish the following subgroups with proposed underlying phenotypes: ‘high muscle strength subgroup’ representing a post-traumatic phenotype, ‘low muscle strength subgroup’ representing an age-induced phenotype and ‘obesity subgroup’ representing a metabolic phenotype.

Objectives:

In the present study, we aimed to validate the construct of this algorithm, focusing on 3 research questions: (i) are the proportions of patients in each subgroup similar across cohorts?; (ii) are the characteristics of each of the subgroups in line with their proposed underlying phenotypes?; (iii) are the effects of usual exercise therapy in the 3 subgroups in line with the proposed effect sizes?

Methods:

Data from five studies (four trials and one cross-sectional cohort) were used to validate the construct of our algorithm by 63 a priori formulated hypotheses regarding the research questions.

Results:

Baseline data from a total of 1,211 patients with knee OA were analyzed for the first and second research question, and follow-up data from 584 patients who were part of an exercise arm within a trial for the third research question. In total, the vast majority (73%) of the hypotheses were confirmed. Regarding our first research question, we found similar proportions in each of the three subgroups across cohorts, especially for three cohorts. Regarding our second research question, subgroup characteristics were almost completely in line with the proposed underlying phenotypes. Regarding our third research question, unexpectedly, usual exercise therapy resulted in similar, moderate to large effect sizes for knee pain and physical function for all three subgroups.

Conclusion:

This study suggests that our algorithm might be a valid instrument to allocate patients with knee OA into clinically relevant subgroups, as most of our a priori hypotheses could be confirmed. On the other hand, subgroups did not differ substantially in effects of usual exercise therapy, contrary to our expectation. An ongoing trial [1] will assess whether this algorithm accompanied by subgroup-specific exercise therapy improves clinical and economic outcomes.

References:

[1]Knoop J, Dekker J, van der Leeden M, de Rooij M, Peter WFH, van Bodegom-Vos L, van Dongen JM, Lopuhäa N, Bennell KL, Lems WF, van der Esch M, Vliet Vlieland TPM, Ostelo RWJG. Stratified exercise therapy compared with usual care by physical therapists in patients with knee osteoarthritis: A randomized controlled trial protocol (OCTOPuS study). Physiother Res Int. 2020 Apr;25(2):e1819. doi: 10.1002/pri.1819. Epub 2019 Nov 28.

Disclosure of Interests:

None declared

POS1470-HPR BARRIERS AND FACILITATORS OF A NEW MODEL OF STRATIFIED EXERCISE THERAPY IN KNEE OSTEOARTHRITIS: A QUALITATIVE STUDY

Background:

We have developed a model of stratified exercise therapy, in which three knee osteoarthritis (OA) subgroups (i.e., ‘high muscle strength subgroup’, ‘low muscle strength subgroup’ and ‘obesity subgroup’) can be distinguished and provided a subgroup-specific intervention. Currently, the (cost-)effectiveness of this model compared to usual exercise therapy is tested in a large-scaled randomized controlled trial (OCTOPuS-study [1]). Alongside this trial, we performed a qualitative study to explore perceived barriers and facilitators of the application of this model in primary care.

Objectives:

To explore barriers and facilitators of the application of this model in primary care, as perceived by patients, physiotherapists and dieticians.

Methods:

Qualitative data were collected through semi-structured interviews in a random sample of 15 patients (5 from each subgroup), 11 physiotherapists and 5 dieticians, from the experimental arm of the OCTUPuS trial. A thematic analysis of the data was performed.

Results:

We identified 14 themes in 5 categories. In general, patients and therapists were positive about the added value and applicability of the model, although some physiotherapists would prefer more flexibility. Regarding the ‘high muscle strength subgroup’, both patients and physiotherapists reported mixed feelings on the low number of supervised sessions, with some perceiving this low number as advantageous for stimulating the patient’s own responsibility, whereas others as hindering an optimally guided treatment. Regarding the ‘obesity subgroup’, dieticians and physiotherapists acknowledged the added value of the combined intervention, but both were disappointed by the lack of interdisciplinary collaboration. Moreover, those patients in this subgroup already following a diet restriction, therefore not perceiving any added value of the diet intervention.

Conclusion:

This qualitative study revealed relevant barriers and facilitators of our new model of stratified exercise therapy, which will help us interpreting the upcoming results on its (cost-) effectiveness [1]. If proven to be (cost-)effective, implementation strategies should specifically focus on guidance of patients from the ‘high muscle strength subgroup’ within only a few sessions, collaboration between physiotherapist and dietician in the ‘obesity subgroup’, and adequate use of booster sessions after the supervised period to optimize treatment adherence.

References:

[1]Knoop J, Dekker J, van der Leeden M, de Rooij M, Peter WFH, van Bodegom-Vos L, van Dongen JM, Lopuhäa N, Bennell KL, Lems WF, van der Esch M, Vliet Vlieland TPM, Ostelo RWJG. Stratified exercise therapy compared with usual care by physical therapists in patients with knee osteoarthritis: A randomized controlled trial protocol (OCTOPuS study). Physiother Res Int. 2020 Apr;25(2):e1819. doi: 10.1002/pri.1819. Epub 2019 Nov 28.

Disclosure of Interests:

None declared

Oral insulin immunotherapy in children at risk for type 1 diabetes in a randomised controlled trial

AIMS/HYPOTHESIS

Oral administration of antigen can induce immunological tolerance. Insulin is a key autoantigen in childhood type 1 diabetes. Here, oral insulin was given as antigen-specific immunotherapy before the onset of autoimmunity in children from age 6 months to assess its safety and immune response actions on immunity and the gut microbiome.

METHODS

A phase I/II randomised controlled trial was performed in a single clinical study centre in Germany. Participants were 44 islet autoantibody-negative children aged 6 months to 2.99 years who had a first-degree relative with type 1 diabetes and a susceptible HLA DR4-DQ8-containing genotype. Children were randomised 1:1 to daily oral insulin (7.5 mg with dose escalation to 67.5 mg) or placebo for 12 months using a web-based computer system. The primary outcome was immune efficacy pre-specified as induction of antibody or T cell responses to insulin and measured in a central treatment-blinded laboratory.

RESULTS

Randomisation was performed in 44 children. One child in the placebo group was withdrawn after the first study visit and data from 22 insulin-treated and 21 placebo-treated children were analysed. Oral insulin was well tolerated with no changes in metabolic variables. Immune responses to insulin were observed in children who received both insulin (54.5%) and placebo (66.7%), and the trial did not demonstrate an effect on its primary outcome (p = 0.54). In exploratory analyses, there was preliminary evidence that the immune response and gut microbiome were modified by the INS genotype Among children with the type 1 diabetes-susceptible INS genotype (n = 22), antibody responses to insulin were more frequent in insulin-treated (72.7%) as compared with placebo-treated children (18.2%; p = 0.03). T cell responses to insulin were modified by treatment-independent inflammatory episodes.

CONCLUSIONS/INTERPRETATION

The study demonstrated that oral insulin immunotherapy in young genetically at-risk children was safe, but was not associated with an immune response as predefined in the trial primary outcome. Exploratory analyses suggested that antibody responses to oral insulin may occur in children with a susceptible INS genotype, and that inflammatory episodes may promote the activation of insulin-responsive T cells.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02547519 FUNDING: The main funding source was the German Center for Diabetes Research (DZD e.V.).

Maternal Type 1 Diabetes Reduces Autoantigen-Responsive CD4+ T Cells in Offspring

Autoimmunity against pancreatic β-cell autoantigens is a characteristic of childhood type 1 diabetes (T1D). Autoimmunity usually appears in genetically susceptible children with the development of autoantibodies against (pro)insulin in early childhood. The offspring of mothers with T1D are protected from this process. The aim of this study was to determine whether the protection conferred by maternal T1D is associated with improved neonatal tolerance against (pro)insulin. Consistent with improved neonatal tolerance, the offspring of mothers with T1D had reduced cord blood CD4⁺ T-cell responses to proinsulin and insulin, a reduction in the inflammatory profile of their proinsulin-responsive CD4⁺ T cells, and improved regulation of CD4⁺ T cell responses to proinsulin at 9 months of age, as compared with offspring with a father or sibling with T1D. Maternal T1D was also associated with a modest reduction in CpG methylation of the INS gene in cord blood mononuclear cells from offspring with a susceptible INS genotype. Our findings support the concept that a maternal T1D environment improves neonatal immune tolerance against the autoantigen (pro)insulin.

Use and perceived added value of patient-reported measurement instruments by physiotherapists treating acute low back pain: a survey study among Dutch physiotherapists

BACKGROUND

This study aims to explore (i) physiotherapists' current use in daily practice of patient-reported measurement instruments (screening tools and questionnaires) for patients with acute low back pain (LBP), (ii) the underlying reasons for using these instruments, (iii) their perceived influence on clinical decision-making, and (iv) the association with physiotherapist characteristics (gender, physiotherapy experience, LBP experience, overall e-health affinity).

METHODS

Survey study among Dutch physiotherapists in a primary care setting. A sample of 650 physiotherapists recruited from LBP-related and regional primary care networks received the survey between November 2018 and January 2019, of which 85 (13%) completed it.

RESULTS

Nearly all responding physiotherapists (98%) reported using screening tools or other measurement instruments in cases of acute LBP; the Quebec Back Pain Disability Scale (64%) and the STarT Back Screening Tool (61%) are used most frequently. These instruments are primarily used to evaluate treatment effect (53%) or assess symptoms (51%); only 35% of the respondents mentioned a prognostic purpose. Almost three-quarters (72%) reported that the instrument only minimally impacted their clinical decision-making in cases of acute LBP.

CONCLUSIONS

Our survey indicates that physiotherapists frequently use patient-reported measurement instruments in cases of acute LBP, but mostly for non-prognostic reasons. Moreover, physiotherapists seem to feel that current instruments have limited added value for clinical decision-making. Possibly, a new measurement instrument (e.g., screening tool) needs to be developed that does fit the physiotherapist's needs and preferences. Our findings also suggest that physiotherapist may need to be more critical about which measurement instrument they use and for which purpose.

Genetic Contribution to the Divergence in Type 1 Diabetes Risk Between Children From the General Population and Children From Affected Families

The risk for autoimmunity and subsequently type 1 diabetes is 10-fold higher in children with a first-degree family history of type 1 diabetes (FDR children) than in children in the general population (GP children). We analyzed children with high-risk HLA genotypes (n = 4,573) in the longitudinal TEDDY birth cohort to determine how much of the divergent risk is attributable to genetic enrichment in affected families. Enrichment for susceptible genotypes of multiple type 1 diabetes-associated genes and a novel risk gene, BTNL2, was identified in FDR children compared with GP children. After correction for genetic enrichment, the risks in the FDR and GP children converged but were not identical for multiple islet autoantibodies (hazard ratio [HR] 2.26 [95% CI 1.6-3.02]) and for diabetes (HR 2.92 [95% CI 2.05-4.16]). Convergence varied depending upon the degree of genetic susceptibility. Risks were similar in the highest genetic susceptibility group for multiple islet autoantibodies (14.3% vs .12.7%) and diabetes (4.8% vs. 4.1%) and were up to 5.8-fold divergent for children in the lowest genetic susceptibility group, decreasing incrementally in GP children but not in FDR children. These findings suggest that additional factors enriched within affected families preferentially increase the risk of autoimmunity and type 1 diabetes in lower genetic susceptibility strata.

Is a model of stratified exercise therapy by physical therapists in primary care feasible in patients with knee osteoarthritis? : a mixed methods study

OBJECTIVES

To explore the feasibility of a newly developed model of stratified exercise therapy in primary care for patients with knee osteoarthritis (OA).

DESIGN

Mixed method design (process, outcome and qualitative evaluation).

SETTING

Six physical therapy practices in primary care around Amsterdam.

PARTICIPANTS

Fifty eligible patients with knee OA, visiting one of the participating physical therapists (PTs).

INTERVENTION

Patients were allocated to a subgroup based on a simple stratification tool and received subgroup-specific, protocolized, 4-month, exercise therapy.

MAIN OUTCOME MEASURES

Feasibility of this model of stratified exercise therapy was explored by multiple process parameters, outcome measures (physical functioning and knee pain; at baseline and 4-months follow-up) and experiences from patients and PTs.

RESULTS

From 97 potentially eligible patients, fifty patients were included and allocated to the 'high muscle strength subgroup' (n=17), 'depression subgroup' (n=4), 'obesity subgroup' (n=6) or 'low muscle strength subgroup' (n=23). Three patients dropped out during the study period. PTs provided relatively low numbers of sessions (on average 10 sessions), although exceedance of the recommended maximum number of sessions did occur frequently. We found clinically relevant improvements on physical functioning and knee pain (P<0.001 for both) for the total group. In general, the model of stratified exercise therapy was considered to be easily applicable and of added value for daily practice.

CONCLUSIONS

Our model of stratified exercise therapy seems to be feasible in primary care, although a number of limitations were reported. Future research should determine the (cost-)effectiveness of an adapted model, compared to usual, non-stratified exercise therapy.

GM-CSF producing autoreactive CD4+ T cells in type 1 diabetes

The phenotype of autoreactive T cells in type 1 diabetes is described as Th1, Th17 and/or Th21, but is largely uncharacterized. We combined multi-parameter cytokine profiling and proliferation, and identified GM-CSF producing cells as a component of the response to beta cell autoantigens proinsulin and GAD65. Overall cytokine profiles of CD4⁺ T cell were not altered in type 1 diabetes. In contrast, patients with recent onset type 1 diabetes had increased frequencies of proinsulin-responsive CD4⁺CD45RA^- T cells producing GM-CSF (p=0.002), IFNγ (p=0.004), IL-17A (p=0.008), IL-21 (p=0.011), and IL-22 (p=0.007), and GAD65-responsive CD4⁺CD45RA^- T cells producing IL-21 (p=0.039). CD4⁺ T cells with a GM-CSF⁺IFNγ^-IL-17A^-IL-21^-IL-22^- phenotype were increased in patients for responses to both proinsulin (p=0.006) and GAD65 (p=0.037). GM-CSF producing T cells are a novel phenotype in the repertoire of T helper cells in type 1 diabetes and consolidate a Th1/Th17 pro-inflammatory pathogenesis in the disease.

Thymus Growth and Fetal Immune Responses in Diabetic Pregnancies

Type 1 diabetes (T1D) during pregnancy possibly affects the development of the thymus and the maturation of the immune system in the offspring. The aim of the ImmunDiabRisk study was to investigate thymus growth and maternal and fetal immune responses in pregnancies with and without T1D. The thymus circumferences of the fetuses of pregnant women with T1D (n=49) and without diabetes (n=59) were measured using ultrasound around the 29th gestational week and standardized for gestational age. Simultaneously, the frequencies and total numbers of cell markers were analyzed by flow cytometry in maternal peripheral blood, and at birth in umbilical cord blood. The standardized circumference of the thymus was similar in fetuses of mothers with and without T1D (p=0.26). We observed higher numbers of FOXP3 Tregs, memory Tregs, erythrocytes, and lymphocytes in the cord blood from T1D pregnancies (p=0.01, p=0.002, p=0.002 and p=0.02, respectively). The frequencies of CD4+/CD8+ T cells correlated positively in maternal blood and umbilical cord blood of mother-child pairs, as did the levels of neutrophils (Spearman's correlation coefficient r=0.43, p=0.02 for CD4+/CD8+ cells; r=0.46, p=0.03 for neutrophils), while no significant correlations were observed between thymus circumference and any cell markers in the child. Parts of the prenatal immune system seem to develop differently in the offspring of mothers with and without T1D. The correlation of Tregs between maternal blood and cord blood may indicate a significant cross-talk between the maternal and fetal immune system.

Clinical phenotypes in patients with knee osteoarthritis: a study in the Amsterdam osteoarthritis cohort

OBJECTIVE

To identify and validate previously established phenotypes of knee osteoarthritis (OA) based on similarities in clinical patient characteristics.

METHODS

Knee OA patients (N = 551) from the Amsterdam OA (AMS-OA) cohort provided data. Four clinical patient characteristics were assessed: upper leg muscle strength, body mass index (BMI), radiographic severity (Kellgren/Lawrence [KL] grade), and depressive mood (the Hospital Anxiety and Depression Scale [HADS] questionnaire). Cluster analysis was performed to identify the optimal number of phenotypes. Differences in clinical characteristics between the phenotypes were analyzed with ANOVA.

RESULTS

Cluster analysis identified five phenotypes of knee OA patients: "minimal joint disease phenotype", "strong muscle strength phenotype", "severe radiographic OA phenotype", "obese phenotype", and "depressive mood phenotype".

CONCLUSIONS

Among patients with knee OA, five phenotypes were identified based on four clinical characteristics. To a high degree, the results are a replication of earlier findings in the OA Initiative, indicating that these five phenotypes seem a stable, valid, and clinically relevant finding.

Evidence of waste electrical and electronic equipment (WEEE) relevant substances in polymeric food-contact articles sold on the European market

In order to confirm the possibility that recycled fractions from the waste electrical and electronic equipment (WEEE) stream were illegally entering the European market in black polymeric food-contact articles (FCAs), bromine quantification, brominated flame retardant (BFR) identification combined with WEEE-relevant elemental analysis and polymer impurity analysis were performed. From the 10 selected FCAs, seven samples contained a bromine level ranging from 57 to 5975 mg kg⁻¹, which is lower than expected to achieve flame retardancy. The BFRs that were present were tetrabromobisphenol A (TBBPA), decabromodiphenylether (decaBDE), decabromodiphenylethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE). Typical elements used in electronic equipment and present in WEEE were detected either at trace level or at elevated concentrations. In all cases when bromine was detected at higher concentrations, concurrently antimony was also detected, which confirms the synergetic use of antimony in combination with BFRs. This study describes also the measurement of rare earth elements where combinations of cerium, dysprosium, lanthanum, neodymium, praseodymium and yttrium were detected in four of the seven BFR-positive samples. Additionally, polymer purity was investigated where in all cases foreign polymer fractions were detected. Despite the fact that this study was carried out on a very small amount of samples, there is a significant likelihood that WEEE has been used for the production of FCAs.

Improvement in upper leg muscle strength underlies beneficial effects of exercise therapy in knee osteoarthritis: secondary analysis from a randomised controlled trial

OBJECTIVES

Although exercise therapy is effective for reducing pain and activity limitations in patients with knee osteoarthritis (OA), the underlying mechanisms are unclear. This study aimed to evaluate if improvements in neuromuscular factors (i.e. upper leg muscle strength and knee proprioception) underlie the beneficial effects of exercise therapy in patients with knee OA.

DESIGN

Secondary analyses from a randomised controlled trial, with measurements at baseline, 6 weeks, 12 weeks and 38 weeks.

SETTING

Rehabilitation centre.

PARTICIPANTS

One hundred and fifty-nine patients diagnosed with knee OA.

INTERVENTION

Exercise therapy.

MAIN OUTCOME MEASURES

Changes in pain [numeric rating scale (NRS)] and activity limitations [Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical function subscale and get-up-and-go test] during the study period. Independent variables were changes in upper leg muscle strength and knee joint proprioception (i.e. motion sense) during the study period. Longitudinal regression analyses (generalised estimating equation) were performed to analyse associations between changes in upper leg muscle strength and knee proprioception with changes in pain and activity limitations.

RESULTS

Improved muscle strength was significantly associated with reductions in NRS pain {B coefficient -2.5 [95% confidence interval (CI) -3.7 to -1.4], meaning that every change of 1 unit of strength was linked to a change of -2.5 units of pain}, WOMAC physical function (-8.8, 95% CI -13.4 to -4.2) and get-up-and-go test (-1.7, 95% CI -2.4 to -1.0). Improved proprioception was not significantly associated with better outcomes of exercise therapy (P>0.05).

CONCLUSIONS

Upper leg muscle strengthening is one of the mechanisms underlying the beneficial effects of exercise therapy in patients with knee OA.

Dipolmomente und scheinbare Leitfähigkeiten von 1.2-Dithia-cyclopenten-thionen-(3) und -onen-(3)

Es sind die Dipolmomente und scheinbaren Leitfähigkeiten von 10 Trithionen und 31 1.2-Dithiacyclopentenonen- (3) bestimmt worden. Die Dipolmomente gestatten die Abschätzung von Elektronenverschiebungen im Molekül bei Eintritt von Substituenten in 5-Stellung.

Is the severity of knee osteoarthritis on magnetic resonance imaging associated with outcome of exercise therapy?

OBJECTIVE

To evaluate associations between severity of knee osteoarthritis (OA) on magnetic resonance imaging (MRI) and treatment outcomes in knee OA patients treated with exercise therapy in an exploratory study.

METHODS

Ninety-five participants with knee OA in a 12-week exercise program had obtained 3.0T MRI scans of the knee joint prior to treatment. MRI data were systematically assessed for OA severity of multiple features (cartilage integrity, bone marrow lesions, osteophyte formation, effusion/synovitis, and meniscal abnormalities) according to the Boston Leeds Osteoarthritis Knee Score method. Regression analyses were performed to analyze associations between OA severity on MRI (for the tibiofemoral and patellofemoral [PF] compartments) and outcome of exercise therapy, i.e., changes in activity limitations (Western Ontario and McMaster Universities Osteoarthritis Index physical function; primary outcome), pain and upper leg muscle strength, and treatment response (Outcome Measures in Rheumatology/Osteoarthritis Research Society International criteria).

RESULTS

Improvements of 24%, 34%, and 21% on average in activity limitations, pain, and muscle strength, respectively, after 12-week exercise therapy were found (P < 0.001). Severity of abnormalities in PF cartilage integrity was significantly associated with fewer improvements in both activity limitations (P = 0.01) and muscle strength (P = 0.04). Severity of PF osteophyte formation was significantly associated with fewer improvements in muscle strength (P < 0.01). All other features on MRI were not associated with treatment outcome.

CONCLUSION

Effectiveness of exercise therapy seems to be independent of OA severity on MRI, except for abnormalities in cartilage integrity and osteophyte formation, both in the PF compartment. Our study suggests that all grades of OA severity on MRI can benefit from professionally supervised exercise therapy, although the effects might be reduced in patients with advanced PF OA.

Knee joint stabilization therapy in patients with osteoarthritis of the knee: a randomized, controlled trial

OBJECTIVE

To investigate whether an exercise program, initially focusing on knee stabilization and subsequently on muscle strength and performance of daily activities is more effective than an exercise program focusing on muscle strength and performance of daily activities only, in reducing activity limitations in patients with knee osteoarthritis (OA) and instability of the knee joint.

DESIGN

A single-blind, randomized, controlled trial involving 159 knee OA patients with self-reported and/or biomechanically assessed knee instability, randomly assigned to two treatment groups. Both groups received a supervised exercise program for 12 weeks, consisting of muscle strengthening exercises and training of daily activities, but only in the experimental group specific knee joint stabilization training was provided. Outcome measures included activity limitations (Western Ontario and McMaster Universities Osteoarthritis Index - WOMAC physical function, primary outcome), pain, global perceived effect and knee stability.

RESULTS

Both treatment groups demonstrated large (∼20-40%) and clinically relevant reductions in activity limitations, pain and knee instability, which were sustained 6 months post-treatment. No differences in effectiveness between experimental and control treatment were found on WOMAC physical function (B (95% confidence interval - CI) = -0.01 (-2.58 to 2.57)) or secondary outcome measures, except for a higher global perceived effect in the experimental group (P = 0.04).

CONCLUSIONS

Both exercise programs were highly effective in reducing activity limitations and pain and restoring knee stability in knee OA patients with instability of the knee. In knee OA patients suffering from knee instability, specific knee joint stabilization training, in addition to muscle strengthening and functional exercises, does not seem to have any additional value. Dutch Trial Register (NTR) registration number: NTR1475.

The association between reduced knee joint proprioception and medial meniscal abnormalities using MRI in knee osteoarthritis: results from the Amsterdam osteoarthritis cohort

BACKGROUND

Osteoarthritis (OA) of the knee is characterized by pain and activity limitations. In knee OA, proprioceptive accuracy is reduced and might be associated with pain and activity limitations. Although causes of reduced proprioceptive accuracy are divergent, medial meniscal abnormalities, which are highly prevalent in knee OA, have been suggested to play an important role. No study has focussed on the association between proprioceptive accuracy and meniscal abnormalities in knee OA.

OBJECTIVE

To explore the association between reduced proprioceptive accuracy and medial meniscal abnormalities in a clinical sample of knee OA subjects.

METHODS

Cross-sectional study in 105 subjects with knee OA. Knee proprioceptive accuracy was assessed by determining the joint motion detection threshold in the knee extension direction. The knee was imaged with a 3.0 T magnetic resonance (MR) scanner. Number of regions with medial meniscal abnormalities and the extent of abnormality in the anterior and posterior horn and body were scored according to the Boston-Leeds Osteoarthritis Knee Score (BLOKS) method. Multiple regression analyzes were used to examine whether reduced proprioceptive accuracy was associated with medial meniscal abnormalities in knee OA subjects.

RESULTS

Mean proprioceptive accuracy was 2.9° ± 1.9°. Magnetic resonance imaging (MRI)-detected medial meniscal abnormalities were found in the anterior horn (78%), body (80%) and posterior horn (90%). Reduced proprioceptive accuracy was associated with both the number of regions with meniscal abnormalities (P < 0.01) and the extent of abnormality (P = 0.02). These associations were not confounded by muscle strength, joint laxity, pain, age, gender, body mass index (BMI) and duration of knee complaints.

CONCLUSION

This is the first study showing that reduced proprioceptive accuracy is associated with medial meniscal abnormalities in knee OA. The study highlights the importance of meniscal abnormalities in understanding reduced proprioceptive accuracy in persons with knee OA.

Proprioception in knee osteoarthritis: a narrative review

OBJECTIVE

To give an overview of the literature on knee proprioception in knee osteoarthritis (OA) patients.

METHOD

A literature search was performed and reviewed using the narrative approach.

RESULTS

(1) Three presumed functions of knee proprioception have been described in the literature: protection against excessive movements, stabilization during static postures, and coordination of movements. (2) Proprioceptive accuracy can be measured in different ways; correlations between these methods are low. (3) Proprioceptive accuracy in knee OA patients seems to be impaired when compared to age-matched healthy controls. Unilateral knee OA patients may have impaired proprioceptive accuracy in both knees. (4) Causes of impaired proprioceptive accuracy in knee OA remain unknown. (5) There is currently no evidence for a role of impaired proprioceptive accuracy in the onset or progression of radiographic osteoarthritis (ROA). (6) Impaired proprioceptive accuracy could be a risk factor for progression (but not for onset) of both knee pain and activity limitations in knee OA patients. (7) Exercise therapy seems to be effective in improving proprioceptive accuracy in knee OA patients.

CONCLUSIONS

Recent literature has shown that proprioceptive accuracy may play an important role in knee OA. However, this role needs to be further clarified. A new measurement protocol for knee proprioception needs to be developed. Systematic reviews focusing on the relationship between impaired proprioceptive accuracy, knee pain and activity limitations and on the effect of interventions (in particular exercise therapy) on proprioceptive accuracy in knee OA are required. Future studies focusing on causes of impaired proprioceptive accuracy in knee OA patients are also needed, taking into account that also the non-symptomatic knee may have proprioceptive impairments. Such future studies may also provide knowledge of mechanism underlying the impact of impaired proprioceptive accuracy on knee pain and activity limitations.