Serum metabolomic profiling identifies potential biomarkers in arthritis in older adults: an exploratory study

BACKGROUND

Seronegative elderly-onset rheumatoid arthritis (EORA)^neg and polymyalgia rheumatica (PMR) have similar clinical characteristics making them difficult to distinguish based on clinical features. We hypothesized that the study of serum metabolome could identify potential biomarkers of PMR vs. EORA^neg.

METHODS

Arthritis in older adults (ARTIEL) is an observational prospective cohort with patients older than 60 years of age with newly diagnosed arthritis. Patients' blood samples were compared at baseline with 18 controls. A thorough clinical examination was conducted. A Bruker Avance 600 MHz spectrometer was used to acquire Nuclear Magnetic Resonance (NMR) spectra of serum samples. Chenomx NMR suite 8.5 was used for metabolite identification and quantification.Student t-test, one-way ANOVA, binary linear regression and ROC curve, Pearson's correlation along with pathway analyses were conducted.

RESULTS

Twenty-eight patients were diagnosed with EORA^neg and 20 with PMR. EORA^neg patients had a mean disease activity score (DAS)-Erythrocyte Sedimentation Rate (ESR) of 6.21 ± 1.00. All PMR patients reported shoulder pain, and 90% reported pelvic pain. Fifty-eight polar metabolites were identified. Of these, 3-hydroxybutyrate, acetate, glucose, glycine, lactate, and o-acetylcholine (o-ACh), were significantly different between groups. Of interest, IL-6 correlated with different metabolites in PMR and EORA^neg suggesting different inflammatory activated pathways. Finally, lactate, o-ACh, taurine, and sex (female) were identified as distinguishable factors of PMR from EORA^neg with a sensitivity of 90%, specificity of 92.3%, and an AUC of 0.925 (p < 0.001).

CONCLUSION

These results suggest that EORA^neg and PMR have different serum metabolomic profiles that might be related to their pathobiology and can be used as biomarker to discriminate between both diseases.

Design of an anti-inflammatory diet (ITIS diet) for patients with rheumatoid arthritis

Background

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that affects synovial joints, leading to inflammation, joint destruction, loss of function, and disability. Although recent pharmaceutical advances have improved treatment of RA, patients with RA often inquire about dietary interventions to improve RA symptoms, as they perceive rapid changes in their symptoms after consumption of certain foods. There is evidence that some ingredients have pro- or anti-inflammatory effects. In addition, recent literature has shown a link between diet and microbiome changes. Both diet and the gut microbiome are linked to circulating metabolites that may modulate inflammation. However, evidence of the effects of an anti-inflammatory and probiotic-rich diet in patients with RA is scarce. There is also a need for biological data to support its anti-inflammatory effects.

Methods

The main goal of this study is to delineate the design process for a diet tailored to our RA population. To achieve this goal, we collected information on diet, supplements, cooking methods, and intake of different ingredients for each patient. Different groups were interviewed, and their feedback was assessed to design a diet that incorporates suggested anti-inflammatory ingredients in a manner that was easy for patients to adopt based on their lifestyles and backgrounds.

Results

We designed a diet that includes a high intake of potential anti-inflammatory ingredients. Feedback from highly motivated patients was critical in constructing an anti-inflammatory diet (ITIS diet) with elevated adherence.

Conclusion

In order to tailor our diet, we surveyed our patients on several different parameters. We obtained important feedback on how feasible our ITIS diet is for RA patients. Using this feedback, we made minor improvements and finalized the design of the ITIS diet. This diet is being used in an on-going pilot study to determine their anti-inflammatory effect in pain and joint swelling in RA patients.

Trial registration

Not applicable.

Evaluation of retinal microvascular perfusion in hereditary angioedema: a case-control study

Evidence supports that hereditary angioedema (HAE) may be considered as a paroxysmal permeability disorder with defective but self-limiting endothelial barrier dysfunction. A potential subclinical abnormal vascular permeability at retinal capillaries could induce damage resulting in retinopathy. We aimed at exploring for the first time the presence of microangiopathy at retinal level from a highly selective cohort of patients with HAE due to C1 esterase inhibitor protein (C1INH) deficiency (type I). We conducted a pilot, prospective, case-control study including 20 type I HAE patients and 20 age−/sex-matched healthy controls (HC). All participants underwent standard ophthalmological examination including visual fields. Superficial and deep capillary plexi in the retina were analyzed by using new optical coherence tomography angiography (OCT-A). A total of 40 eyes from 20 HAE patients and 20 eyes from HC were evaluated. Perimetric indices of visual field were slightly worse in HAE than in controls. OCT-angiograms documented in HAE patients a lower retinal capillary density in both superficial and deep scans and a higher retinal thickness compared to healthy eyes. Our findings firstly documented subclinical abnormalities in retinal microvascular network in type I HAE patients that might be associated with early subtle functional changes. This preliminary evidence supports the hypothesis of a recurrent endothelial barrier failure at retinal level in HAE patients potentially resulting in chronic damage.

Use of synthetic and biological DMARDs in patients with enteropathic spondyloarthritis: a combined gastro-rheumatological approach

OBJECTIVES

The aim of this 2-year prospective study was to assess the diagnostic and therapeutic effect of a combined gastro-rheumatological approach in enteropathic spondyloarthritis (eSpA) patients.

METHODS

Inflammatory bowel disease (IBD) patients with joint pain were referred by IBD-dedicated gastroenterologists to a dedicated rheumatologist. At baseline and at 3, 6, 12, 24 months, the following parameters were recorded: clinical and biochemical variables, SpA and IBD activity scores, treatment (conventional synthetic; csDMARDs, biologics; bDMARDs). Associations between treatment and patient characteristics were evaluated by logistic regression (AOR [95% CI]).

RESULTS

Overall, 229 IBD patients were referred to rheumatologists. eSpA was diagnosed in 147 (64.2%) patients: 96 (65.3%) showing peripheral and 51 (34.7%) axial involvement. IBD included Crohn's disease (CD) in 141 (61.6%) and ulcerative colitis (UC) in 88 (38.4%). bDMARD treatment increased over the follow-up (baseline-24 months: 32.7-60%; AOR 3.45 [1.93-6.2], p<0.001). bDMARD use was less frequent in elderly patients (AOR 0.73 [0.56-0.96], p=0.023), in UC (AOR 0.43 [0.2-0.94], p=0.034) and in patients with peripheral involvement (AOR 0.53 [0.3-1.04], p=0.067). csDMARD use was increased in patients with peripheral involvement (AOR 4.65 [2.09-10.33], p<0.001) and in UC (AOR 2.30 [1.13-4.67], p=0.021). CRP, ESR, ASDAS-ESR levels and BASFI significantly decreased over the follow-up, whereas the pMayo score, BASDAI and HAQ-S were unchanged.

CONCLUSIONS

In this prospective study in eSpA patients, a multidisciplinary approach was shown to optimise the therapeutic management and outcome (e.g. disease activity scores). bDMARD use paralleled an improvement in disease activity scores and confirmed a good safety profile.