Lihi Eder

Cardiovascular and other comorbidities in patients with psoriatic arthritis: A comparison with patients with psoriasis

To determine whether the presence of psoriatic arthritis (PsA) is associated with greater comorbidity, in particular cardiovascular morbidity, compared to psoriasis without arthritis.

Patients with psoriatic arthritis have worse quality of life than those with psoriasis alone

OBJECTIVE PsA is an inflammatory arthritis present in ∼30% of people with psoriasis (PsC). Both conditions have a significant impact on quality of life (QoL). Our objective was to test the hypothesis that people with PsA have poorer QoL than patients with PsC because of the added burden of arthritis, age and comorbidities. METHODS Consecutive patients with PsA (CASPAR criteria) and PsC were approached to participate in this study. Patients with PsC were examined by a rheumatologist using a standardized protocol to exclude PsA. Patients completed the HAQ, Medical Outcome Study 36-item Short Form Health Survey, Dermatology Life Quality Index (DLQI), EuroQoL 5 domains (EQ-5D) and Fatigue Severity Scale (FSS). Mean scores were compared and multivariate analyses were conducted to compare the QoL measures between the two patient groups. RESULTS Two hundred and one patients with PsC and 201 patients with PsA were studied. A significant decrease in QoL for patients with PsA compared with those with PsC was identified by all questionnaires except for the DLQI. This skin-specific questionnaire revealed a lower QoL in patients with PsC. Multivariate analyses for each QoL measure confirmed the results of these analyses. After adjusting for age, sex, duration of PsC, comorbidities, DMARDs and biologic therapy, HAQ and DLQI were independently associated with PsA in a logistic regression. CONCLUSION Patients with PsA have a poorer QoL compared with those with PsC as measured by all questionnaires except the DLQI.

Human leucocyte antigen risk alleles for psoriatic arthritis among patients with psoriasis

Aim Genes that differentiate patients with psoriatic arthritis (PsA) from those with cutaneous psoriasis (PsC) may serve as markers for the development of PsA in patients with psoriasis. The authors aimed to identify human leucocyte antigen (HLA) alleles that are associated with the development of PsA in patients with psoriasis. Methods 712 adult patients with PsA, 335 adult patients with PsC and 713 healthy controls were genotyped for HLA-A, HLA-B, HLA-C, HLA-DR and HLA-DQ alleles. Differences in allelic distributions for each of the HLA loci were compared using a likelihood ratio test. Logistic regression analysis of multiple loci was performed to account for linkage disequilibrium. Haplotype information was inferred using the expectation–maximisation algorithm (given HLA-C and HLA-B genotypes) and analysed similarly. Results The following HLA alleles were found to be significantly associated with patients with PsA compared to patients with PsC in multivariate regression analysis: B*08 (OR 1.61, p=0.009), B*27 (OR 5.17, p<0.0001), B*38 (OR 1.65, p=0.026) and C*06 (OR 0.58, p=0.0002). HLA-B*27, HLA-B*38 and HLA-C*06 frequencies were also significantly higher in patients with PsA than in healthy controls (B*27: OR 3.05, p<0.0001; B*38: OR 5.9, p<0.0001; HLA-C*06: OR 1.71, p<0.0001). The following haplotypes were independently associated with PsA compared to PsC: HLA-B*18-C*07 (OR 10.1, p=0.004), HLA-B*27-C*01 (OR 41.1, p<0.0001), HLA-B*27-C*02 (OR 19.9, p<0.0001), HLA-B*38-C*12 (OR 2.9, p=0.01), HLA-B*08-C*07 (OR 2.6, p=0.004) and HLA-B*57-C*06 (OR 0.5, p=0.03). Conclusions Certain HLA-B and HLA-C alleles confer susceptibility to PsA among patients with psoriasis and may be used to identify patients with PsC who may develop PsA.

Association between environmental factors and onset of psoriatic arthritis in patients with psoriasis

To investigate the association between potential environmental exposures and the development of psoriatic arthritis (PsA) in patients with psoriasis.

Obesity is associated with a lower probability of achieving sustained minimal disease activity state among patients with psoriatic arthritis

Aim To assess whether overweight and obese patients with psoriatic arthritis (PsA) are less likely to achieve sustained minimal disease activity (MDA) state compared to patients with normal weight. Methods A cohort of patients was assessed at the University of Toronto PsA clinic at 6–12-month intervals according to a standard protocol from 2003 to 2012. Patients were categorised into the following groups according to their body mass index (BMI): normal (<25), overweight (25–30), and obese (>30). Sustained MDA was defined as achieving low disease activity state in five or more of the following domains for at least 1 year: skin, enthesitis, tender and swollen joint counts, pain, patient global assessment and function. Proportional odds discrete time to event analysis was used to investigate the association between BMI category and the achievement of sustained MDA. Results Of the 557 patients included in the study, 36.2% were classified as overweight and 35.4% were obese. Overall, 66.1% of the patients achieved sustained MDA during the follow-up period. A dose–response association was found between obesity and the probability of achieving sustained MDA in the multivariate regression analysis. Patients in the higher BMI categories were less likely to achieve sustained MDA compared those in the lowest BMI category (overweight: OR 0.66 p=0.003; obese: OR 0.53 p<0.0001) after adjusting for potential confounding variables. Conclusions Overweight and obese patients with PsA are less likely to achieve sustained MDA compared to those of normal weight.

Depression and Anxiety in Psoriatic Disease: Prevalence and Associated Factors

Objective. (1) To determine the prevalence of depression and anxiety in patients with psoriatic arthritis (PsA) and to identify associated demographic and disease-related factors. (2) To determine whether there is a difference in the prevalence of depression and anxiety between patients with PsA and those with psoriasis without PsA (PsC). Methods. Consecutive patients attending PsA and dermatology clinics were assessed for depression and anxiety using the Hospital Anxiety and Depression Scale. Patients underwent a clinical assessment according to a standard protocol and completed questionnaires assessing their health and quality of life. T tests, ANOVA, and univariate and multivariate models were used to compare depression and anxiety prevalence between patient cohorts and to determine factors associated with depression and anxiety. Results. We assessed 306 patients with PsA and 135 with PsC. There were significantly more men in the PsA group (61.4% vs 48% with PsC) and they were more likely to be unemployed. The prevalence of both anxiety and depression was higher in patients with PsA (36.6% and 22.2%, respectively) compared to those with PsC (24.4% and 9.6%; p = 0.012, 0.002). Depression and/or anxiety were associated with unemployment, female sex, and higher actively inflamed joint count as well as disability, pain, and fatigue. In the multivariate reduced model, employment was protective for depression (OR 0.36) and a 1-unit increase on the fatigue severity scale was associated with an increased risk of depression (OR 1.5). Conclusion. The rate of depression and anxiety is significantly higher in patients with PsA than in those with PsC. Depression and anxiety are associated with disease-related factors.

Incidence of arthritis in a prospective cohort of psoriasis patients

Epidemiologic studies about the incidence of psoriatic arthritis (PsA) are limited to a few population‐based studies. There are limited data regarding the incidence of PsA in patients with psoriasis. We aimed to determine the incidence of PsA among a prospective cohort of psoriasis patients.

Is ASDAS better than BASDAI as a measure of disease activity in axial psoriatic arthritis

Objective To assess the discriminative ability and correlation of the Ankylosing Spondylitis Disease Activity Score (ASDAS) and Bath Ankylosing Spondylitis Activity Disease Activity Index (BASDAI) with disease activity in axial psoriatic arthritis (AxPsA). Methods Patients with AxPsA were selected from a large prospective cohort study of psoriatic arthritis. Patient and physician global scores were used as constructs of disease activity. Patients were categorised into high and low disease activity states based on patient and physician global assessment scores and physicians decision to change treatment. Statistical analysis included descriptive statistics, linear and logistic regression. Results 201 patients with AxPsA were included in the study. ASDAS and BASDAI showed good correlation with disease activity as reflected by the patient global score (correlation coefficients (r) for BASDAI 0.84, ASDAS-B 0.77, ASDAS-C 0.81, p<0.001) and the physician global score (r=0.53 for BASDAI, r=0.50 for ASDAS-B, r=0.55 for ASDAS-C, p<0.001). Both scores showed good discriminative ability between high and low disease activity states. However, there were no significant differences between areas under the curve for the models that compared ASDAS with BASDAI for each definition of disease activity state. Conclusions In patients with AxPsA, ASDAS and BASDAI scores show similar good to moderate discriminative ability and correlation with different constructs of disease activity. ASDAS was not superior to BASDAI in its ability to discriminate between high and low disease activity states in AxPsA.

The association between smoking and the development of psoriatic arthritis among psoriasis patients

Aim To investigate the association between smoking and psoriatic arthritis (PsA) among patients with psoriasis and its interaction with the HLA-C*06 allele. Methods In this exploratory case–control study, smoking status was determined at the time of the diagnosis of arthritis for PsA patients and at their first study visit for psoriasis patients, when they were confirmed not to have PsA. The proportions of patients exposed to smoking were compared in patients with PsA to those with psoriasis alone. A logistic regression model was constructed to test the independent association of smoking and PsA after adjusting for potential confounders. The statistical interaction between HLA-C*06 and smoking was tested through a regression model. Results The proportions of current and past smokers were higher in the psoriasis group compared with the PsA group (30.2% vs 23.4% and 26.7% vs 22.3%, p=0.001, respectively). On multivariate analysis being a current smoker versus a lifetime non-smoker remained inversely associated with PsA (OR 0.57, p=0.002), while past smoker versus lifetime non-smoker status was no longer significant. In a subgroup analysis, smoking remained inversely associated with PsA only among patients who were HLA-C*06 negative. Regression analysis revealed that the interaction between smoking status (ever smoked vs lifetime non-smoker) and HLA-C*06 was statistically significant (p=0.01). Conclusion Smoking may be inversely associated with PsA among psoriasis patients. This association is not present among HLA-C*06-positive individuals.

Predictors of response to intra-articular steroid injection in psoriatic arthritis

OBJECTIVES To assess the effectiveness of IA corticosteroid (IAS) injections in PsA and to determine the association between macrophage migration inhibition factor (MIF) gene polymorphism and response to IAS injections. METHODS A cohort analysis of PsA patients who were followed prospectively was performed. Clinical response was defined as no tenderness or effusion in the injected joint at 3 months. Relapse was defined as re-occurrence of joint pain or effusion. MIF 173C > G genotyping (rs755622) was performed. RESULTS Two hundred and twenty patients with 245 IAS injections were included in the study. The probability of responding at 3 months was 41.6%. Within 12 months, 25.5% of the joints relapsed. Clinical factors that were associated with response included duration of psoriasis [Odds ratio (OR) 1.03] and the use of MTX or anti-TNF agents at the time of injection (OR 2.68). Factors that were associated with relapse included injection into large joints (OR 4.58) and elevated sedimentation rate (OR 15.0), whereas absence of clinical and/or radiographic damage (OR 0.23) and duration of PsA (OR 0.92) reduced risk of relapse. MIF polymorphism was not associated with clinical response, but was associated with relapse (OR 3.2). On multivariate analysis including clinical covariates, the association between MIF polymorphism and relapse was lost. CONCLUSIONS IAS injections are effective in PsA. MIF gene polymorphism is associated with relapse. However, this effect is explained by clinical variables that reflect disease activity, suggesting that MIF gene polymorphism influences inflammatory activity.