Serum IL-23 significantly decreased in obese patients with psoriatic arthritis six months after a structured weight loss intervention.

INTRODUCTION: Patients with psoriatic arthritis (PsA) are frequently obese. We have previously shown decreased disease activity in patients with PsA with a body mass index (BMI) ≥ 33 kg/m2 following weight loss treatment with Very Low Energy Diet (VLED), resulting in a median weight loss of 18.6% at six months (M6) after baseline (BL). In this study we assessed the effects of VLED on cytokines and adipokines at M6 in the same patients with PsA and controls (matched on sex, age and weight). METHODS: VLED (640 kcal/day) during 12 or 16 weeks, depending on BL BMI < 40 or ≥ 40 kg/m2, was taken and followed by an energy-restricted diet. Cytokines and adipokines were measured with Magnetic Luminex Assays at BL and M6. RESULTS: Serum interleukin (IL)-23, (median (interquartile range) 0.40 (0.17-0.54) ng/mL vs. 0.18 (0.10-0.30) ng/mL, p < 0.001) and leptin (26.28 (14.35-48.73) ng/mL vs. 9.25 (4.40-16.24) ng/mL, p < 0.001) was significantly decreased in patients with PsA. Serum total (tot)-adiponectin and high molecular weight (HMW) adiponectin increased significantly. Similar findings were found in controls. Also, in patients with PsA, ∆BMI was positively correlated with ∆IL-23 (rS = 0.671, p < 0.001). In addition, significant positive correlations were found between ΔBMI and ΔDisease Activity Score (DAS28CRP), ΔCRP, Δtumor necrosis factor (TNF)-α, ΔIL-13, ∆IL-17 and Δleptin, and negative correlations between ΔBMI and Δtot-adiponectin. CONCLUSIONS: Weight loss was associated with decreased levels of leptin and cytokines, in particular IL-23. These findings may partly explain the anti-inflammatory effect of weight reduction in PsA. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02917434, registered on September 21, 2016, retrospectively registered.

Health-related quality of life in gout, psoriatic arthritis, rheumatoid arthritis and ankylosing spondylitis, results from a cross-sectional survey in Western Sweden.

OBJECTIVES: Inflammatory joint diseases (IJDs) substantially affect health-related quality of life (HRQoL). We aimed to compare HRQoL between patients with gout, psoriatic arthritis (PsA), rheumatoid arthritis (RA), and ankylosing spondylitis (AS): (i) overall; (ii) stratified by sex; and (iii) between women and men with the same IJD diagnosis. METHOD: A survey including the RAND36-Item Health Survey for assessing HRQoL was sent to patients with a diagnosis of gout, PsA, RA, or AS, registered at a rheumatology clinic or primary care centre during 2015-2017. HRQoL was compared across IJDs. Because of age differences between diagnoses, age-matched analyses were performed. RESULTS: In total, 2896/5130 (56.5%) individuals responded to the questionnaire. Of these, 868 had gout, 699 PsA, 742 RA, and 587 AS. Physical component summary (PCS) scores were more affected than mental component summary (MCS) scores for all diagnoses (PCS range: 39.7-41.2; MCS range: 43.7-48.9). Patients with gout reported better PCS scores than patients with PsA, RA, and AS, who reported similar scores in age-matched analysis. MCS scores were close to normative values for the general population and similar across IJDs. When comparing women and men with respective IJDs, women reported worse PCS (range, all IJDs: 34.5-37.4 vs 37.5-42.5) and MCS (PsA: 44.0 vs 46.8; RA: 46.1 vs 48.7) scores. CONCLUSION: We found that patients with gout reported better PCS scores than patients with other IJDs, for whom the results were similar. Women reported overall worse PCS and MCS scores than men.

Validity of clinical psoriatic arthritis diagnoses made by rheumatologists in the Swedish National Patient Register.

OBJECTIVES: : Knowledge of the correspondence between clinical ICD diagnoses and classification criteria fulfilment is crucial to interpret studies identifying cases via ICD codes. We assessed the degree to which patients registered with ICD-10 diagnoses of psoriatic arthritis (PsA) in the Swedish National Patient Register (NPR) fulfil established PsA classification criteria. METHOD: Four hundred patients with at least one outpatient visit to one of five rheumatology or internal medicine departments (three university/two county departments across Sweden) in 2013-2015, with a main ICD-10 diagnosis of PsA (L40.5, M07.0-M07.3), were randomly selected (80 cases/site). Through a structured medical record review, positive predictive values (PPVs) for fulfilment of the following classification criteria were assessed: CASPAR, Moll and Wright, Vasey and Espinoza, and modified ESSG criteria for PsA. A subset analysis regarding CASPAR fulfilment was also performed among cases with available rheumatoid factor and peripheral X-ray status (central CASPAR items; n = 227). RESULTS: Of the 400 patients with a main ICD-10 diagnosis of PsA, 343 (86%) fulfilled at least one of the four PsA classification criteria. PPVs for the different criteria were: CASPAR 69% (82% in the subset analysis), Moll and Wright 51%, Vasey and Espinoza 76%, and modified ESSG 64%. Overall, only 6.5% of the 400 PsA diagnoses were judged as clearly incorrect by the medical record reviewers. CONCLUSION: The validity of rheumatologist-made, clinical ICD-10 diagnoses for PsA in the Swedish NPR is good, with PPVs of 69-82% for CASPAR fulfilment and 86% for meeting any established PsA classification criteria.

Cardiovascular risk factors are highly overrepresented in Swedish patients with psoriatic arthritis compared with the general population.

Objectives: We aimed to determine the prevalence of cardiovascular risk factors in patients with psoriatic arthritis (PsA) followed at a large Swedish Rheumatology Clinic, and to compare differences in cardiovascular risk factors between men and women with PsA and with the general population.Method: A questionnaire was sent to patients with PsA registered at the Rheumatology Clinic at Sahlgrenska University Hospital, Gothenburg (n = 982). Comparisons with the general population were made using data from the Swedish National Public Health Survey. Descriptive statistics are presented. Body mass index (BMI) was calculated using self-reported height and weight.Results: Overall, 692 (70.6%) of the patients with PsA responded. The mean ± sd age was 55.6 ± 11.4 years and 52% were women. Obesity (BMI ≥ 30 kg/m2) was more prevalent (p < 0.001) in patients with PsA (28.6%) than in matched subjects from the general population (16.3%). Hypertension was also more prevalent (p < 0.001) in PsA (40.3%) than in matched subjects from the general population (24.1%), as was diabetes, with a prevalence of 10.5% in the PsA population compared with 6.2% in matched subjects (p < 0.001).Conclusion: We found obesity to be highly overrepresented in patients with PsA compared with matched subjects from the general population. This difference was particularly seen in women with PsA. Hypertension and ever smoking were also more prevalent in women with PsA compared with matched subjects from the general population.

Hepatocyte growth factor is a potential biomarker for osteoproliferation and osteoporosis in ankylosing spondylitis.

We explored relations between serum hepatocyte growth factor (HGF), disease activity, osteoproliferation, and bone mineral density (BMD) in ankylosing spondylitis (AS), in comparison with healthy controls. HGF was increased especially in male AS patients and smokers and associated with both lower BMD and more chronic radiographic changes in the spine. INTRODUCTION: Ankylosing spondylitis (AS) is characterized by both osteoproliferation and increased bone loss. Biomarkers are requested to predict the processes. The aims of this study were to compare serum levels of hepatocyte growth factor (HGF), matrix metalloproteinase-3 (MMP-3), and vascular endothelial growth factor (VEGF) in AS patients with healthy controls (HC) and to explore the associations with disease activity, osteoproliferation, and bone mineral density (BMD). METHODS: Serum from AS patients (modified NY-criteria) and HC was analyzed for HGF, MMP-3, and VEGF with ELISA. Disease activity parameters were collected. Osteoproliferation was assessed with modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) and BMD was measured in femoral neck. RESULTS: Totally, 204 AS patients and 80 sex and age matched HC were included. Serum HGF was higher in the AS patients compared with the HC, whereas serum MMP-3 and VEGF were not. Serum HGF was also higher in smokers and in the male AS patients positively correlated with age, BASMI, and mSASSS, and negatively correlated with BMD. The biomarkers were all positively associated with ESR, CRP, and WBC. In multiple linear regression analysis serum HGF remained associated with higher mSASSS and lower BMD, after adjusting for age, sex, CRP, smoking, and body mass index. CONCLUSIONS: Serum HGF was increased in male AS patients and associated with higher mSASSS and lower BMD. In addition, serum HGF was positively associated with risk factors for osteoproliferation such as age, CRP and smoking. HGF could be a potential biomarker of importance for the bone metabolism in AS. TRIAL REGISTRATION: NCT00858819.

Genetic variants in CARD8 but not in NLRP3 are associated with ankylosing spondylitis.

OBJECTIVES: The NOD-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome is important for interleukin-1beta (IL-1ß) processing as part of an innate immune response. Caspase recruitment domain family, member 8 (CARD8) is an inhibitor of nuclear factor kappa B (NF-κB) and possibly also a part of the NLRP3 inflammasome. The objective of this study was to evaluate one single nucleotide polymorphism (SNP) in CARD8 and three SNPs in NLRP3 in ankylosing spondylitis (AS) susceptibility and disease phenotype. METHOD: We recruited 492 AS patients from Southern Sweden fulfilling the modified New York criteria for AS, and assessed phenotypic characteristics from medical records and questionnaires. Patients with psoriasis or clinically overt inflammatory bowel disease (IBD) were excluded, as were patients without human leucocyte antigen B27 (HLA-B27). Three NLRP3 SNPs (rs35829419, rs4353135, and rs10733113) and one SNP in CARD8 (rs2043211) were genotyped by commercially available TaqMan assays, and the results compared at genotype and allele levels to those of 793 population-based controls. In a subgroup of the patients (n = 169), faecal calprotectin was assessed as a marker of subclinical intestinal inflammation. RESULTS: The minor allele (A) of CARD8-C10X (rs2043211) was associated with a decreased risk of AS in a dominant model [odds ratio (OR) 0.74, 95% confidence interval (CI) 0.54-0.94, p = 0.012] and at the allelic level (OR 0.81, 95% CI 0.68-0.97, p = 0.02), but was not associated with levels of faecal calprotectin. There was no association regarding NLRP3 SNPs and AS susceptibility, and none of the investigated SNPs were associated with iritis, anti-tumour necrosis factor (anti-TNF) therapy, or peripheral joint involvement. CONCLUSION: In a Swedish population, the minor allele of CARD8-C10X is associated with a decreased risk of AS, but not with levels of faecal calprotectin or disease phenotype.