Background:Continuous glucose monitoring (CGM) improves glycaemic management in adults with type 1 diabetes (T1D), but may be associated with weight gain. We assessed changes in body weight and HbA1c after CGM initiation and characterized weight-glycemia trajectories. Methods:We retrospectively analysed 4178 adults with T1D initiating CGM from the DPV registry (DPV-CGM; n = 2104) and a pooled Belgian cohort (BE-CGM; n = 2074). Outcomes over 24 months were evaluated using paired t-tests and group-based multi-trajectory modelling. In DPV, CGM initiators were compared with matched controls without CGM (n = 2104; matched for sex, age, diabetes duration, baseline weight, and HbA1c). Findings:After 24 months, mean body weight increased by 1.8 kg [95% CI: 1.5; 2.0] in DPV-CGM and 1.0 kg [0.8; 1.2] in the BE-CGM cohort, while HbA1c decreased by -0.2% [-0.1; -0.2] and -0.1% [-0.03; -0.1], respectively (all p < 0.0001). In DPV-controls, weight increased by 1.2 kg [0.9; 1.5] (p < 0.01) and HbA1c decreased by 0.06% [-0.001; -0.11] (p = 0.05). Three trajectories were identified. The first showed modest weight gain with HbA1c improvement: 147/2104 (7.0%) DPV-CGM vs 99/2104 (4.7%) DPV-controls, and 411/2074 (19.8%) in BE-CGM. The second, largest group, showed stable weight and HbA1c: 1773/2104 (83.2%) DPV-CGM vs 1612/2104 (74.7%) controls in DPV-controls, and 1447/2074 (69.8%) in BE-CGM. The third, an unfavourable trajectory characterized by substantial weight gain (≈8 kg) with stable HbA1c, included 184/2104 (9.9%) DPV-CGM vs 393/2104 (20.5%) DPV-controls, and 216/2074 (10.4%) in BE-CGM (ꭓ2 p < 0.01). Interpretation:CGM initiation was associated with modest weight gain and improved HbA1c. Compared with matched controls, CGM users were less likely to belong to the unfavourable weight gain with stable HbA1c trajectory, which occurred in 9.9% vs 20.5%, respectively. Funding:Innovative Medicines Initiative2 Joint Undertaking under grant agreement No. 875534.

Cardiovascular disease (CVD) is a major long-term complication and the leading cause of morbidity and mortality among individuals with type 1 diabetes (T1D), with a substantially higher prevalence compared to the general population and driven by multiple interrelated risk factors-underscoring the urgent need for accurate risk assessment. To support more tailored approaches to CVD prevention, recently, five discordant phenotypic risk profiles for CVD were identified in the general population in Europe with diverse relationship between body mass index and cardiometabolic biomarkers. Here, we show their applicability in 44,212 people with T1D. Improved glycemic control was linked to a decrease in CVD risk as people with T1D with lower glycated hemoglobin belonged to the baseline concordant cluster. This supports the contention that glycemic control in people with T1D is an integral part of lowering CVD risk.

There is a lack of knowledge on the registration of body mass index (BMI) and prevalence of obesity-related complications in the Belgian healthcare system. We therefore evaluated these in Belgians living with overweight or obesity. BMI registration and obesity-related complication prevalences were determined using cross-sectional data from a Belgian general practitioners' morbidity registry (Intego) with 208 891 personal records and from 3605 visitors to an obesity clinic. Two Intego data subsets were used: 53 555 individuals with and 84 017 individuals without registered BMI. Groups were compared using chi-square tests (p-value of < 0.05). For Intego data, BMI was registered in 25.6% of cases. Individuals with registered BMI (mean BMI 27.1 ± 5.5 kg/m2) had a higher prevalence of hypertension (30.1% vs. 17.0%), dyslipidemia (26.9% vs. 14.7%), prediabetes (17.0% vs. 7.9%), type 2 diabetes (12.7% vs. 4.4%) and sleep apnea (3.8% vs. 1.5%) compared to people without registered BMI. People assessed at the obesity clinic (mean BMI 39.0 ± 6.5 kg/m2) had higher prevalences of hypertension (43.1% vs. 37.5%), dyslipidemia (44.4% vs. 32.9%) and sleep apnea (37.9% vs. 5.5%) compared to Intego individuals with BMI ≥ 25 kg/m2(mean BMI 30.3 ± 4.3 kg/m2). BMI is registered only in 25% of patient files in general practice, and people with a registered BMI in general practice have a substantially higher prevalence of the five obesity-related complications than people without registered BMI. When registered, mean BMI is substantially lower than in the obesity clinic, but the prevalence of complications is already substantial, though lower than in the obesity clinic.

Objective: To assess the effect of metabolic bariatric surgery (MBS) in people living with type 1 diabetes (T1D) and obesity. Research Design and Methods: From retrospective multicenter data, total weight loss, daily insulin requirement, HbA1c and cardiometabolic parameters were assessed pre-and post-surgery. Longitudinal models were used to identify response determinants. Results: 162 people living with T1D and obesity were included. One year after surgery, mean total weight loss was 29.7% [29.4-30.3]. Insulin requirements dropped from 0.75 [0.58-1.00] u/kg/day to 0.32 [0.23-0.43] u/kg/day (p<0.001) and HbA1c (64.0 [57.0-74.0] mmol/mol to 60.0 [53.4-68.0] mmol/mol; (p<0.001). LDL, HDL, total cholesterol and triglycerides significantly improved after surgery (p<0.001). Greater total weight loss was associated with reduced insulin requirements while higher baseline HbA1c was associated with poorer post-surgery glycemic-control. Conclusions: MBS was associated with substantial metabolic improvement in people with T1D and obesity, in particular in those with high HbA1c and insulin need at baseline.

Background: To assess changes in HbA1c and weight over time after continuous glucose monitoring (CGM) initiation in adults with type 1 diabetes (T1D). Methods: Retrospective data from 4178 adults with T1D using CGM in Western Europe were analyzed. To assess changes in weight and HbA1c over 24 months after CGM initiation, paired t-tests and group-based multi-trajectory modeling were used. Findings : After 24 months of CGM initiation, a mean weight gain of 1.8kg±5.1 (p<0.0001) and 1.0kg±4.6 (p<0.0001) with a decrease in HbA1c of -1.7±10.7 mmol/mol (-0.2%±1.0; p<0.0001) and -0.7±8.9 mmol/mol (-0.1%±0.8; p<0.0001) were seen in the diabetes registry (DPV) (n=2104) and in the FUTURE/RESCUE (BE) cohort (n=2074), respectively. Three distinct bi-variate trajectories were identified in both cohorts: some weight gain with HbA1c decrease (DPV: 7.0% of cohort, weight +3.8kg, HbA1c -2.3%; BE: 20.5% of cohort, weight +1.3kg, HbA1c -1.1%), stable weight and HbA1c (DPV: 83.2%, weight +0.59kg, HbA1c-0.01%; BE: 68.1%, weight -0.27kg, HbA1c+0.2%), and weight gain with stable HbA1c (DPV: 9.9%, weight +11.1kg, HbA1c +0.01%; BE: 11.4%, weight +8.2kg, HbA1c -0.01%). Interpretation: CGM initiation resulted in a modest weight increase and HbA1c decrease. However, 10% of individuals experienced notable weight gain despite stable HbA1c, underscoring the persistent unmet need for additional strategies to avoid weight gain and improve glucose control.

Insufficient weight loss or weight regain after metabolic and bariatric surgery (MBS) is frequent, and evidence to support the use of pharmacotherapy for weight management is limited. In this single-centre retrospective cohort study, the effectiveness of naltrexone/bupropion (NB) for weight control in surgery-naive and post-MBS patients was evaluated. Data was collected between 2016 and 2022 on all patients started on NB after multidisciplinary consult. Patients received weekly dose escalation up to 32/360 mg daily per the manufacturer’s protocol, with submaximal doses administered in cases of adverse effects or sufficient therapeutic response. Weight evolution, metabolic status, adherence and adverse events were analysed at 4 and 12 months after NB initiation. Data are presented as median (interquartile range). A total of 151 patients were included, 111 were surgery-naive and 40 with prior MBS. The median time after MBS was 7.1 years (4.2, 14.9). Among the post-MBS patients, 18 (45

Long-term data indicate that patients who underwent metabolic bariatric surgery have a higher risk of developing nutritional complications. Therefore, it is of utmost importance to monitor their nutritional status. A scoping literature search was conducted in MEDLINE, EMBASE, CINAHL, and TRIP database to identify clinical practice guidelines for nutritional screening before and after metabolic bariatric surgery from learned societies. For full coverage, all websites of learned societies affiliated with the World Obesity Federation were searched. Clinical practice guidelines were eligible if they contained recommendations for nutritional screening before and after sleeve gastrectomy or Roux-en-Y gastric bypass. Content was screened by two reviewers for timing, biochemical markers and cut-off values, and biochemical assays for nutritional screening. Nine eligible clinical practice guidelines co-authored by 26 learned societies were identified. All guidelines provided recommendations for both bariatric procedures except for one. Majority of guidelines endorsed nutritional screening before surgery and at 3, 6, 12, and 24 months after surgery, and annually thereafter. Pre- and postoperative screening recommendations were available for iron, vitamin B12, folate, calcium and vitamin D, but in a lesser extent for vitamin A, vitamin E, vitamin K, zinc, vitamin B1, copper and magnesium. Two clinical practice guidelines provided cut-off values for the diagnosis of nutritional deficiencies. The clinical practice guidelines exhibited a high level of consistency for timing of screening, but not for the applied biochemical markers. Going forward, the primary focus should be on harmonizing recommendations for biochemical markers, and cut-off values.

Rituximab is known as an efficacious drug for the treatment of Rheumatoid Arthritis (RA). The original administration schedule consisted of two infusions of 1000 mg with a 2-week interval. We aimed to explore the long-term effectiveness of rituximab in daily clinical practice in patients with RA. Data of patients with RA treated with rituximab in a tertiary university hospital (2006–2019) were retrospectively collected from rituximab initiation until December 1st 2019 or rituximab discontinuation, whichever came first. Rituximab retreatment was based on a treat-to-target-approach guided by a 28-joint disease activity score (DAS28) ≥ 3.2, as dictated by national reimbursement criteria. Rituximab retention rate was investigated using a Kaplan-Meier survival curve. We collected data of 104 patients (59

Objectives Systemic autoimmune rheumatic diseases (SARDs) develop in genetically susceptible individuals when exposed to environmental factors such as respirable crystalline silica (RCS) particles. Assessing occupational exposure in population-based studies is critical but resource intensive, often requiring expert interviews. This study aimed to develop and validate a self-administered occupational history questionnaire that allows for International Standard Classification of Occupations 1968 (ISCO-68) coding and exposure assessment as a cost-effective alternative to traditional interviews.Methods Seventy RA patients participated by completing a standardized telephone interview and the newly developed self-administered questionnaire. Participants were also asked to recruit two gender- and age-matched family members for comparison. Independent observers assigned ISCO-68 codes to the reported jobs and a job exposure matrix was used to link each job to RCS exposure. Agreement between the interview and questionnaire was assessed by comparing reported working years, ISCO-68 job codes and RCS exposure. Cohen's kappa and intraclass correlation were calculated to evaluate agreement and interobserver variability.Results The patient response rate was 77%, but family member controls had a low response rate (6.45%), likely impacted by the COVID-19 pandemic. Agreement for reported working years was 91%, with a Cohen's kappa of 0.87 for ever/never RCS exposure. Manual ISCO coding introduced variability, but interobserver reliability remained high (intraclass correlation coefficient = 0.91).Conclusion The self-administered occupational history questionnaire provides a valid, cost-effective and time-efficient alternative to telephone interviews for assessing occupational history and estimating RCS exposure in epidemiological research. Future studies should explore automated coding systems and improved strategies for control recruitment. What does this mean for patients?The origin of autoimmune diseases (e.g. rheumatoid arthritis) is largely unknown. There is increasing evidence that, in addition to hereditary factors, environmental factors play a role. We assume that the profession a person carries out or has carried out in the past largely determines his/her exposure to potentially harmful substances, of which respirable crystalline silica (that is released when cutting stone) is one. The gold standard to estimate occupational exposure is an interview with an industrial hygienist. This technique is time consuming, expensive and not applicable in clinical daily practice. For this reason, we developed a questionnaire on occupational history that can be completed by the patient independently. We tested the performance of our questionnaire to measure occupational exposure to silica, comparing it to an interview. Furthermore, we evaluated if there are important differences in silica exposure when the questionnaire is rated by different researchers. We conclude that our questionnaire can be used to estimate occupational exposure to silica and it can be used by different observers. Having a validated questionnaire available means medical doctors can easily get detailed information on the occupational history of patients. This can be used in future research on the onset of autoimmune diseases.

OBJECTIVES:The aim of this work was to determine whether smartphone applications could support the self-management of RA and to investigate engagement and potential negative psychological effects with app-use. METHODS:App-based Education and GOal-setting in RA (AEGORA) was a multicentre randomized controlled trial with 2:1:1 allocation to usual care or two versions of an app-based self-management intervention for RA. The 16-week programme involved patient education, goal-setting and remote monitoring of the Rheumatoid Arthritis Impact of Disease (RAID) instrument, either weekly or monthly depending on randomization. The primary end point was improvement in the Arthritis Self-Efficacy Scale (ASES) after 16 weeks. Secondary endpoints included non-inferiority regarding the Pain Catastrophizing Scale (PCS) and superiority regarding patient-reported physical activity, sleep quality and RAID. App engagement and RAID scores were analysed descriptively. RESULTS:Overall, 122 patients were included: mean (s.d.) disease duration 12 (9) years, age 58 (11), 68% female, DAS28-CRP 2.4 (0.9). The intervention did not improve the ASES score over usual care (β 0.44, P = 0.87). Non-inferiority was established for the PCS (β -0.95 [95% CI -3.30, +1.40] favouring the intervention). Other predefined outcomes did not differ. App retention steadily declined to 43% by 16 weeks. Although the RAID remained stable over time overall, 35% of app users reported ≥1 episode of clinically relevant worsening over 16 weeks. CONCLUSION:This app-based self-management intervention was not superior to usual care regarding self-efficacy improvement. However, remote symptom monitoring provided valuable insight and did not increase pain catastrophizing, alleviating concerns regarding the psychological impact of remote monitoring with apps. TRIAL REGISTRATION NUMBER:clinicaltrials.gov, NCT05888181.

Objectives To investigate serum lipid profile in early, treatment-naïve psoriatic arthritis (PsA) and to determine whether changes in classical lipids or apolipoproteins are specific to PsA.Methods Total cholesterol, non-high-density lipoprotein cholesterol (non-HDL-c), low-density lipoprotein cholesterol (LDL-c), HDL-c, triglycerides, apolipoprotein B (ApoB) and apolipoprotein A1 (ApoA1) were compared in newly diagnosed untreated PsA patients (n=75) to sex- and age-matched controls (healthy control (HC)) (n=61) and early untreated rheumatoid arthritis (RA) patients (n=50).Results Among classical lipid measurements, HDL-c levels were lower in PsA than in HC and RA (df 2, χ210, p=0.006, PsA vs HC p=0.013). Significant differences in ApoA1 and ApoB levels were observed between PsA, RA and controls. ApoB was higher in PsA than in RA patients but lower than in controls (df2, χ243.8; p<0.001). ApoA1 was markedly lower in PsA patients compared with both RA and controls (df2, χ2118.9; p<0.001). In regression models, the levels of ApoA1, adjusted for additional factors, were predictive of PsA diagnosis with 90.6% accuracy. In receiver operating characteristic analysis, ApoA1 was predictive of the diagnosis of PsA with a specificity of 82.4% and a sensitivity of 83.8% at an optimal cut-off value of 1403 µg/mL (area under the curve (95% CI), 0.886 (0.83 to 0.941)).Conclusion Early, treatment-naïve PsA patients exhibit a distinct pro-atherogenic lipid profile, characterised by decreased ApoA1 and increased ApoB levels, distinguishing them from early RA patients and healthy controls. These findings highlight the potential of apolipoprotein measurements to serve as more accurate indicators of lipid disturbances in PsA than traditional serum lipids and as aid to diagnosis of patients presenting with early arthritis.

OBJECTIVES:C reactive protein (CRP) is frequently normal in psoriatic arthritis (PsA) despite active disease, complicating inflammation assessment. This study aimed to evaluate alternative biomarkers of inflammation in early PsA. METHODS:Adult patients with early, treatment-naïve PsA were enrolled in the prospective multicentre cohort and compared with early rheumatoid arthritis (RA) and healthy controls (HCs). Clinical assessments, inflammatory markers and peripheral blood counts were collected. For this study, baseline and 1-year data were used. Serum complement factor 3 (C3), calprotectin (S100A8/9) and serum amyloid A (SAA) were measured by ELISA. Discriminatory performance was evaluated using receiver operating characteristic curve analysis. RESULTS:A total of 67 PsA, 50 RA patients and 61 HC were included. At baseline, median levels of C3 (1.38 g/L) and S100A8/9 (5.58 µg/mL) were significantly elevated in PsA compared with HC and were comparable to RA. In the 'CRP-negative' subgroup, C3 and S100A8/9 were increased in PsA as compared with HC. In the obese subgroup, CRP levels did not discriminate PsA, RA and HC. However, S100A8/9 was significantly increased in PsA and RA as compared with HC, whereas SAA and derived inflammatory ratios (neutrophil/monocyte ratio, lymphocyte/monocyte ratio) did not discriminate PsA, RA or HC. After 1 year, C3 and S100A8/9 decreased significantly in PsA patients achieving low disease activity. In the obese subgroup, the composite marker C3×calprotectin demonstrated superior diagnostic performance as compared with CRP (area under the curve=0.836). CONCLUSIONS:C3 and calprotectin are elevated in early PsA and are responsive to treatment. These markers outperform CRP in obese and CRP-negative patients and may support improved diagnosis and disease monitoring in clinical practice.

Recent advancements in obesity pharmacotherapy have seen the approval of novel agents, like glucagon-like peptide-1 receptor agonist and dual agonists, offering unprecedented efficacy for obesity management. However, treatment outcomes remain highly variable, necessitating a more personalized approach to pharmacotherapy tailored to individual profiles. This review evaluates the current landscape of obesity pharmacotherapy, while exploring factors influencing variability in treatment response including early response predictors, genetic markers, and physiological traits. Additionally, the potential of combining treatment modalities and some emerging drugs are highlighted. Finally, a stepwise algorithm is proposed for personalized obesity treatment, integrating comorbidities, phenotypes, and responses to medication, paving the way for more effective and efficient obesity management.

BACKGROUND:Early detection of the disease obesity and support for patients living with obesity could improve the success of obesity treatment and management. The factors influencing the delay in obesity treatment, defined as the period between obesity onset and treatment start, are largely unknown. The aim of our study is to explore the help-seeking behavior of PwO towards obesity treatment. METHODS:In this cross-sectional qualitative study, consecutive patients visiting the obesity clinic of the University Hospitals of Brussels between December 2023 and April 2024 were invited to participate. PwO were interviewed, and data were transcribed and analysed using thematic analysis. RESULTS:A total of 18 PwO (61% female, median age 37 years, (IQR: 23.5-57.5)) were interviewed. The journey of PwO towards obesity care seemed complex with multiple HCPs involved. Four themes were identified as triggers for seeking obesity care: Referral from primary care, family, friends and schools; Health complications; Financial burden of living with obesity; and Increased internal motivation. Three themes were identified as factors increasing treatment delay: Inefficient referral; Pressure from society to try lifestyle approaches first; and Challenges to overcome barriers for metabolic surgery. Inefficient referral from dietitians to multidisciplinary obesity treatment was identified as the main cause of treatment delay. PwO feel discouraged by the limited effectiveness of dietary guidance, leading to disengagement from the healthcare system. CONCLUSION:Our findings identify several key barriers contributing to treatment delays for patients with obesity. People living with obesity emphasized the need for an obesity care pathway and improved communication among primary care providers, allied health professionals, and collaborating centres for obesity management (COMs) to reduce the time required to access appropriate obesity treatment. Additionally, societal perceptions framing obesity as a result of a lack of willpower were reported by patients with obesity as a barrier to seeking care.

Objectives To investigate if patients with early rheumatoid arthritis responding insufficiently to initial methotrexate (MTX) and bridging glucocorticoids (GCs) could benefit from early but temporary etanercept introduction as a second remission-induction attempt.Methods CareRA2020 (NCT03649061) was a 2-year, open-label, multicentre, pragmatic randomised controlled trial. Treatment-naïve patients started MTX and GC bridging (COBRA-Slim: CS). Within a time window from week (W) 8 until W32, early insufficient responders (28-joint Disease Activity Score – C-reactive Protein (DAS28-CRP) >3.2 between W8 and W32 or ≥2.6 at W32) were randomised to a Standard-CS strategy (adding leflunomide first) or Bio-induction-CS strategy (adding etanercept for 24 weeks). Additional treatment adaptations followed the treat-to-target principle. Longitudinal disease activity (DAS28-CRP) over 104 weeks (primary outcome), achievement of DAS28-CRP <2.6 28 weeks after randomisation, and biologic or targeted synthetic disease-modifying antirheumatic drug (b/tsDMARD) use at W104 were compared between randomisation groups.Results Following CS treatment, 142 patients were early responders; 55 early insufficient responders received Standard-CS and 55 Bio-induction-CS. Superiority of Bio-induction-CS over Standard-CS could not be demonstrated (ß=−0.204, (95% CI –0.486 to 0.078), p=0.157) for the primary outcome. More patients on Bio-induction-CS achieved DAS28-CRP <2.6 at 28 weeks after randomisation (59% (95% CI 44% to 72%) vs 44% (95% CI 31% to 59%) in Standard-CS) and they were treated less frequently with b/tsDMARDs at W104 (19/55, 35%) compared with Standard-CS (29/55, 53%).Conclusion Half of the patients responded well to initial COBRA-Slim induction therapy. In early insufficient responders, adding etanercept for 6 months did not improve disease control over 104 weeks versus adding leflunomide first. However, temporary introduction of etanercept resulted in improved disease control early after randomisation and less patients on b/tsDMARDs at W104.Trial registration number NCT03649061.CTR pilot approval Belgium S59474, EudraCT number: 2017-004054-41.

AimsType 1 diabetes mellitus (T1DM) is characterised by insulin deficiency. Due to perceived physical activity (PA)-related hypoglycaemia, a minority of people with T1DM exercise regularly. However, the relationship between T1DM and PA remains poorly understood. Our aim was to summarise the existing literature on the effects of PA on short-term glucose control (glycated haemoglobin or time in range) in people with T1DM.MethodsWe searched seven electronic databases (PubMed, Embase, Cochrane library, Cinahl, SPORTDiscus, PEDro and Web Of Science) and two sources of the grey literature ( and ICTRP). All reviews were screened via title/abstract and full text by two independent reviewers (LE and HT), conflicts were solved by a third independent reviewer (DDC). We excluded animal studies, case reports, non-English articles, qualitative studies, conference abstracts and articles without full-text access. A meta-analysis using random effects model was performed to study the effect of PA on haemoglobin A1c (HbA1c) levels in people with T1DM.ResultsWe obtained 19,201 unique references across nine different electronic databases. After screening and snowballing, 68 articles were found investigating the effect of PA on glycaemic control in people with T1DM. Overall, HbA1c levels in the PA group (mean difference = 0.29% (0.20%-0.39%)), were lower compared with the control group.ConclusionAn overall small beneficial effect of PA on glycaemic control in people with T1DM was found. Caution is advised when interpreting the results of this meta-analysis, given variations in study type, duration, frequency and intensity of physical activity across included studies.

Background: Systemic inflammation is an integral part of psoriatic arthritis (PsA). Despite substantial inflammation in the affected tissues such as the skin, entheses and joints, C-reactive protein (CRP) levels are often not elevated in PsA. Consequently, acute phase reactants such as CRP are not highly reliable in measuring inflammation in PsA, especially also in early PsA, when CRP is frequently negative. Objectives: The aim of this study was to investigate whether alternative inflammation markers can detect systemic inflammation in early PsA patients that have normal CRP level. Methods: Adult patients with early (median[IQR] disease duration, years: 0.6[2.08]) DMARD-naïve PsA (N=67) were compared to sex- and age matched healthy controls (HC; N=61) and early (median[IQR] disease duration, years:0.50[.49]) DMARD-naïve RA patients (N=50). Clinical and lab data (including CRP) were collected at baseline and after 1 year for PsA and RA. Potential markers of inflammation were selected according to the literature (serum amyloid A, calprotectin (S100A8/9), complement C3, thrombocytes, mean platelet volume (MPV), ferritin) and measured in the serum. The markers were compared in the three groups (PsA, HC, RA) at baseline as well as in PsA patients having a normal CRP level (≤5 mg/L) and HC. Sensitivity and specificity analysis (ROC) was conducted for the selected markers in “CRP-negative” PsA group. In PsA and RA the measurements were additionally compared at baseline and at 1 year. Correlation analysis (Spearman) between the markers and clinical parameters (age, BMI, TJC68, SJC66, PASI, SPARCC) was performed at baseline (all PsA patients). Results: Thirty nine (58%) of 67 PsA patients, 28 (56%) of the 50 RA patients and 56 (91.8%) of the 61 HC had a normal CRP. Demographic, clinical and disease activity characteristics of PsA patients having CRP≤5mg/L and CRP>5mg/L were comparable. The mean levels of C3 (Cohen’s d 0.22, p<0.001), S100A8/9 (Cohen’s d 0.18, p<0.001) and SAA (Cohen’s d 0.19, p<0.001) were higher in CRP-negative PsA patients than in HC (Figure 1). Thrombocytes, MPV and ferritin were not different between CRP-negative PsA patients, CRP-negative RA patients and HC. No significant difference between the levels of C3, S100A8/9 and SAA between CRP-negative PsA and RA patients was found. When analysing the total cohort (CRP-positive and CRP-negative PsA, RA and HC) we found similar results, with higher calprotectin, C3 and SAA levels in PsA and RA than in HC (p<0.001 for all comparisons). ROC curve analysis in PsA patients and HC with normal CRP was performed. The AUC for C3 was 0.734 [0.63-0.839] with sensitivity and specificity of 71.1% and 60.4% accordingly for a cut off value of 0.99 g/L (Figure 2). In CRP-negative PsA patients, C3, calprotectin and SAA, next to CRP declined significantly after 1 year follow-up due to treatment, which coincides with the improvement of disease activity parameters (TJC68, SC68, DAPSA). Furthermore, the observation that calprotectin and C3 levels correlated with TJC68 and SJC66 and C3 levels with TJC68, SJC66, PASI and SPARCC scores in PsA patients, suggest that these markers are indeed associated with inflammation in PsA. Conclusion: In CRP-negative PsA, complement C3, serum calprotectin and SAA are elevated and could be used for measuring systemic inflammation in patients with early PsA with normal CRP levels. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: None declared.Figure 1Baseline complement C3, SAA, S100A8/9 in CRP-negative PsA and RA patients and healthy controls (HC) Figure 2ROC curve analysis for baseline C3, SAA and calprotectin with CRP-negative PsA as a positive classifier (vs HC) in patients with CRP ≤5 mg/L, baseline.