No predictive effect of body mass index on clinical response in patients with rheumatoid arthritis after 24 weeks of biological disease-modifying antirheumatic drugs: a single-center study

Obesity is a risk factor for poor response to treatment in early rheumatoid arthritis: a NORD-STAR study

OBJECTIVE

This report from the NORD-STAR (Nordic Rheumatic Diseases Strategy Trials and Registries) trial aimed to determine if obesity is associated with response to conventional and biological antirheumatic treatment in early rheumatoid arthritis (RA).

METHODS

This report included 793 participants with untreated early RA from the randomised, longitudinal NORD-STAR trial, all of whom had their body mass index (BMI) assessed at baseline. Obesity was defined as BMI ≥30 kg/m2. All participants were randomised 1:1:1:1 to one of four treatment arms: active conventional treatment, certolizumab-pegol, abatacept and tocilizumab. Clinical and laboratory measurements were performed at baseline and at 8, 12, 24 and 48-week follow-up. The primary endpoint for this report was response to treatment based on Clinical Disease Activity Index (CDAI) and Simple Disease Activity Index (SDAI) remission and Disease Activity Score with 28 joints using C-reactive protein (DAS28-CRP) <2.6 stratified by BMI.

RESULTS

Out of 793 people included in the present report, 161 (20%) had obesity at baseline. During follow-up, participants with baseline obesity had higher disease activity compared with those with lower BMI, despite having similar disease activity at baseline. In survival analyses, obesity was associated with a lower likelihood of achieving response to treatment during follow-up for up to 48 weeks (CDAI remission, HR 0.84, 95% CI 0.67 to 1.05; SDAI, HR 0.77, 95% CI 0.62 to 0.97; DAS28-CRP <2.6, HR 0.78, 95% CI 0.64 to 0.95). The effect of obesity on response to treatment was not influenced by the treatment arms.

CONCLUSION

In people with untreated early RA followed up for up to 48 weeks, obesity was associated with a lower likelihood of good treatment response, irrespective of the type of randomised treatment received.

TRIAL REGISTRATION NUMBER

NCT01491815.

Impact of obesity and overweight on C-reactive protein concentrations and disease activity in rheumatoid arthritis: A systematic review and meta-analysis

AIM

This study aims to assess the association of obesity and CRP concentrations in adult patients with rheumatoid arthritis (RA), and its influence on measures of disease activity.

METHODS

A comprehensive search was performed using Scopus, Web of Science, MEDLINE, and EMBASE, from the time of their inception to November 2021. Observational studies that evaluated the association between CRP concentrations and obesity or overweight in patients with RA were considered eligible. Correlation coefficients were pooled using the inverse variance method, while effect sizes were pre-calculated for adjusted standardized regression coefficients (β).

RESULTS

A total of 10 studies, which comprised 4024 patients, were included in this systematic review. Individually, most studies report a significant association between CRP concentrations and a higher body mass index or other adiposity measures, but the statistical significance was not sustained when pooling their data together. Through the estimates provided in the present review, it is noted that CRP tends to be more elevated in female patients with RA that have a higher BMI. However, this association is not present in men.

CONCLUSION

CRP tends to be elevated in female patients with RA that have a higher BMI. Further research is required to assess this possible sex-related difference and to aid shared decision-making in order to avoid over-treatment and increased burden in patients with obesity and RA. PROSPERO registration number: CRD42022314580.

Effect of body mass index on treatment response of biologic-/targeted synthetic-DMARDs in patients with rheumatoid arthritis, psoriatic arthritis and axial spondyloarthritis. A systematic review

BACKGROUND

Overweight and/or obese patients with inflammatory arthritis (IA) have higher disease activity and lower chances of achieving and/or maintaining the treatment targets. Weight/obesity also appears to negatively affect the response to tumor necrosis factor (TNF) inhibitors in patients with IA, including rheumatoid arthritis -RA, psoriatic arthritis -PsA, axial spondyloarthritis -AxSpA. We conducted a systematic literature review (SLR) for the effect of weight/body-mass-index (BMI) in the efficacy of all approved b- and targeted-synthetic (ts)- DMARDs for the treatment of IA.

METHODS

For this PROSPERO-registered SLR, we searched PubMed, Scopus and Cohrane-Library from inception up to June 21st 2022. Clinical-trials (randomized and non-randomized) and observational studies of RA, PsA or AxSpA patients that reported the effect of weight/BMI on response (all possible outcomes) to b/ts-DMARDs were included. Risk-of-bias was assessed via RoB2-Cochrane-tool and Newcastle-Ottawa-scale for randomized and non-randomized studies, respectively.

FINDINGS

Out of 996 references, 75 eventually fulfilled the inclusion criteria (of which 10 studies were retrieved through manual-search). Among the included studies (TNF-inhibitors: 34, IL-12/23 inhibitors: 4, IL-23 inhibitor: 1, IL-17 inhibitors: 7, tocilizumab: 18, abatacept: 8, rituximab: 3, JAK-inhibitors: 5), most had medium RoB. Efficacy of TNF-inhibitors was affected by BMI in all forms of IA. Data are not robust to compare the effect among various TNF-inhibitors. In contrast, favorable results of IL-23 and IL-17 inhibitors did not appear to be influenced by increased BMI in PsA or AxSpA patients. Similar evidence exists for tocilizumab (in RA) and for abatacept (in RA and PsA), while no conclusion can be drawn for rituximab. More data are needed for JAK-inhibitors, although the effect of weight/BMI does not seem to be significant so far.

INTERPRETATION

Weight/BMI should be considered in the treatment-plan of patients with IA, with its effect being more pronounced for TNF-inhibitors compared to other b/ts-DMARDs.

The growing role of precision medicine for the treatment of autoimmune diseases; results of a systematic review of literature and Experts' Consensus

Autoimmune diseases (AIDs) share similar serological, clinical, and radiological findings, but, behind these common features, there are different pathogenic mechanisms, immune cells dysfunctions, and targeted organs. In this context, multiple lines of evidence suggest the application of precision medicine principles to AIDs to reduce the treatment failure. Precision medicine refers to the tailoring of therapeutic strategies to the individual characteristics of each patient, thus it could be a new approach for management of AIDS which considers individual variability in genes, environmental exposure, and lifestyle. Precision medicine would also assist physicians in choosing the right treatment, the best timing of administration, consequently trying to maximize drug efficacy, and, possibly, reducing adverse events. In this work, the growing body of evidence is summarized regarding the predictive factors for drug response in patients with AIDs, applying the precision medicine principles to provide high-quality evidence for therapeutic opportunities in improving the management of these patients.

Body mass index and treatment survival in patients with RA starting treatment with TNFα-inhibitors: long-term follow-up in the real-life METEOR registry

Objectives

To study whether there is an association between body mass index (BMI) category and survival of various tumour necrosis factor inhibitors (TNFi) in rheumatoid arthritis (RA) patients in a real-life longitudinal international registry.

Methods

Data from 5230 patients with RA starting treatment with any TNFi were selected from the METEOR registry. Patients were divided into six BMI categories: 3.7% underweight, BMI<18.5 kg/m²; 46% normal weight, BMI 18.5–25 kg/m²; 32% pre-obesity, BMI 25–30 kg/m²; 13% obesity class I, BMI 30–35 kg/m²; 3.4% obesity class II, BMI 35–40 kg/m²; and 1.6% obesity class III, BMI >40 kg/m². Time on treatment in the different BMI categories was compared for all TNFi combined and for the infliximab, adalimumab and etanercept separately, using Kaplan–Meier curves and Cox regression analyses. Cox regression analyses were adjusted for potential confounders, with follow-up censored at 5000 days.

Results

Patients in obesity class II (HR 1.28, 95% CI 1.06 to 1.54) and III (HR 1.67, 95% CI 1.29 to 2.18) and underweight patients (HR 1.30, 95% CI 1.07 to 1.58) showed statistically significantly shorter TNFi survival than normal weight patients. The effect in underweight patients was strongest for infliximab (HR 1.82, 95% CI 1.20 to 2.76), the effect in overweight patients was strongest for infliximab (category II (HR 1.49, 95% CI 0.98 to 2.26); category III (HR 1.46, 95% CI 0.79 to 2.71)) and etanercept (category II (HR 1.27 95% CI 0.98 to 1.65); category III (HR 1.79, 95% CI 1.25 to 2.55)). No significant effect modification from reported pain was found.

Conclusion

Both underweight and overweight patients discontinued TNFi treatment earlier than normal weight patients, without evidence of reported pain as the main determinant. It remains uncertain what determines TNFi survival in individual patients.

The Influence of Overweight and Obesity on Treatment Response in Juvenile Idiopathic Arthritis

Background: There is evidence that obesity could be a risk factor for the severity and response to treatment in adult patients with rheumatoid arthritis (RA) due both to the mechanical effect of overweight and to the potential pro-inflammatory effects of cytokines produced by adipose tissue.

Objectives: To evaluate the role of overweight and obesity in a cohort of young patients with juvenile idiopathic arthritis (JIA) in terms of incidence, disease activity, outcome, and response to treatments.

Methods: This single-center retrospective cohort study evaluated 110 children affected by JIA under treatment with conventional disease-modifying antirheumatic drugs (DMARDs) and biologic agents. Body mass index (BMI) categories of 5–84th (normal weight), 85–94th (overweight), and ≥95th (obese) percentile were used. Patients with systemic JIA, uveitis, chronic comorbidities, or under other potentially confounding systemic treatments were excluded. Uni- and multivariate analyses were performed.

Results: One hundred and ten JIA patients (polyarticular n = 50, oligoarticular n = 38, psoriatic n = 12, enthesitis-related arthritis n = 8, undifferentiated n = 2) were enrolled in the study, 75% girls and 25% boys. The mean age at treatment onset was 6.09 years. Baseline BMI was ≥5th and ≤84th percentile in 80 patients, 85–94th in 27, and ≥95th in 3.

We did not observe a significant association between BMI and erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), or number of active joints at baseline, while involvement of the joints of lower limbs was significantly greater ( p = 0.025) in overweight/obese patients. However, a trend toward lower remission rates and higher number of relapses, both after DMARDs and biologics, in patients with higher BMI was observed.

Conclusion: This study focuses on the relationship between overweight/obesity and JIA. A significant correlation between obesity and a greater involvement of the joints of the lower limbs at baseline was demonstrated. Furthermore, our data suggest that obesity could negatively influence the course of the disease as well as treatment response.

Assessing prognosis and prediction of treatment response in early rheumatoid arthritis: systematic reviews

BACKGROUND

Rheumatoid arthritis (RA) is a chronic, debilitating disease associated with reduced quality of life and substantial costs. It is unclear which tests and assessment tools allow the best assessment of prognosis in people with early RA and whether or not variables predict the response of patients to different drug treatments.

OBJECTIVE

To systematically review evidence on the use of selected tests and assessment tools in patients with early RA (1) in the evaluation of a prognosis (review 1) and (2) as predictive markers of treatment response (review 2).

DATA SOURCES

Electronic databases (e.g. MEDLINE, EMBASE, The Cochrane Library, Web of Science Conference Proceedings; searched to September 2016), registers, key websites, hand-searching of reference lists of included studies and key systematic reviews and contact with experts.

STUDY SELECTION

Review 1 - primary studies on the development, external validation and impact of clinical prediction models for selected outcomes in adult early RA patients. Review 2 - primary studies on the interaction between selected baseline covariates and treatment (conventional and biological disease-modifying antirheumatic drugs) on salient outcomes in adult early RA patients.

RESULTS

Review 1 - 22 model development studies and one combined model development/external validation study reporting 39 clinical prediction models were included. Five external validation studies evaluating eight clinical prediction models for radiographic joint damage were also included. c-statistics from internal validation ranged from 0.63 to 0.87 for radiographic progression (different definitions, six studies) and 0.78 to 0.82 for the Health Assessment Questionnaire (HAQ). Predictive performance in external validations varied considerably. Three models [(1) Active controlled Study of Patients receiving Infliximab for the treatment of Rheumatoid arthritis of Early onset (ASPIRE) C-reactive protein (ASPIRE CRP), (2) ASPIRE erythrocyte sedimentation rate (ASPIRE ESR) and (3) Behandelings Strategie (BeSt)] were externally validated using the same outcome definition in more than one population. Results of the random-effects meta-analysis suggested substantial uncertainty in the expected predictive performance of models in a new sample of patients. Review 2 - 12 studies were identified. Covariates examined included anti-citrullinated protein/peptide anti-body (ACPA) status, smoking status, erosions, rheumatoid factor status, C-reactive protein level, erythrocyte sedimentation rate, swollen joint count (SJC), body mass index and vascularity of synovium on power Doppler ultrasound (PDUS). Outcomes examined included erosions/radiographic progression, disease activity, physical function and Disease Activity Score-28 remission. There was statistical evidence to suggest that ACPA status, SJC and PDUS status at baseline may be treatment effect modifiers, but not necessarily that they are prognostic of response for all treatments. Most of the results were subject to considerable uncertainty and were not statistically significant.

LIMITATIONS

The meta-analysis in review 1 was limited by the availability of only a small number of external validation studies. Studies rarely investigated the interaction between predictors and treatment.

SUGGESTED RESEARCH PRIORITIES

Collaborative research (including the use of individual participant data) is needed to further develop and externally validate the clinical prediction models. The clinical prediction models should be validated with respect to individual treatments. Future assessments of treatment by covariate interactions should follow good statistical practice.

CONCLUSIONS

Review 1 - uncertainty remains over the optimal prediction model(s) for use in clinical practice. Review 2 - in general, there was insufficient evidence that the effect of treatment depended on baseline characteristics.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016042402.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Body Mass Index and Clinical Response to Tocilizumab in Patients With Rheumatoid Arthritis

Objectives

This study aims to determine whether baseline body mass index (BMI) affects clinical response to tocilizumab (TCZ) after six months of treatment in rheumatoid arthritis (RA) patients.

Patients and methods

In this prospective study, a total of 52 RA patients (10 males, 42 females; mean age 50.6±12.2 years; range, 23 to 73 years) receiving intravenous TCZ were consecutively recruited and followed-up for six months. BMI was calculated before initiation of TCZ treatment. The primary clinical response criterion was clinical disease activity index (CDAI) low disease activity (LDA) and the secondary clinical response criteria included CDAI remission, disease activity score based on 28 joints (DAS28)-erythrocyte sedimentation rate (ESR) LDA, DAS28-ESR remission, European League Against Rheumatism (EULAR) good response, and decreased DAS28-ESR (ΔDAS28-ESR)≥1.2.

Results

The number of RA patients classified as normal weight, overweight, and obese according to baseline BMI was 38 (73.1%), eight (15.4%), and six (11.5%), respectively. Similar baseline BMI median levels were found between RA patients reaching CDAI LDA and non-LDA: 21.11 (18.94-23.72) versus 20.78 (20.03-22.29) (p=0.98), and non-significant difference in the proportion of responders between normal weight and overweight/obese RA patients was found (p=0.47). No significant difference was found when the secondary clinical response criteria were applied.

Conclusion

Our study demonstrates that BMI is not associated with clinical response to TCZ among RA patients and TCZ may be used to treat RA patients regardless of BMI levels.

Impact of obesity on the efficacy of different biologic agents in inflammatory diseases: A systematic review and meta-analysis

OBJECTIVE

Obesity is a worldwide epidemic and a growing body of evidence suggests that it may affect the body's response to biologic agents. We investigated the influence of obesity on the efficacy of different biologic agents used to treat inflammatory diseases.

METHODS

Medline, EMBASE and the Cochrane Database were searched using relevant MeSH and keyword terms for obesity and bDMARDs. Articles were selected if they reported a clinical response in obese subjects relative to other BMI categories. Response and remission outcomes were assessed using meta-analysis and all other reported outcomes were summarized.

RESULTS

Among the 3850 records retrieved, 24 articles met the inclusion criteria, including 10 on rheumatoid arthritis (RA), 4 on axial spondyloarthritis (axSpA), 4 on Crohn's disease (CD), 4 on psoriasis (Ps) and 2 on psoriasic arthritis (PsA). Four biological disease-modifying anti-rheumatic drugs (bDMARDs) - anti-TNF agents, T cell co-stimulation inhibitor (abatacept), IL-6 inhibitor (tocilizumab), and B-cell depletion therapy (rituximab) - were involved. The meta-analysis showed that the odds to reach a good response or achieve remission were lower in obese (BMI>30kg/m²) than non-obese (BMI≤30kg/m²) patients who were treated with anti-TNF agents (good responder % in RA: OR 0.34, 95% CI 0.18-0.64; remission% in RA: OR 0.36, 95% CI 0.21-0.59; BASDAI50% in axSpA: OR 0.41, 95% CI 0.21-0.83), but no significant difference between obese and non-obese was found in patients treated with abatacept (good responder % in RA: OR 0.75, 95% CI 0.42-1.36; remission% in RA: OR 0.84, 95% CI 0.65-1.09) and tocilizumab (good responder % in RA: OR 1.08, 95% CI 0.44-2.63; remission% in RA: OR 0.91, 95% CI 0.50-1.66).

CONCLUSION

Obesity hampered the effect of anti-TNF agents, but not those of abatacept and tocilizumab, suggesting that a personalized treatment strategy should be considered for obese patients with inflammatory diseases.