Clinical and Genetic Risk Factors Associated with Psoriatic Arthritis among Patients with Psoriasis

Relationship of psoriatic arthritis with nail and scalp involvement in Turkish psoriasis patients: Multicentered cross-sectional study

Psoriasis is a common multisystem inflammatory disease, and arthritis is an essential component of the disorder, requiring early diagnosis and prompt treatment for successful management. In this study, we aimed to investigate the relationship between nail and scalp involvement and other covariates with psoriatic arthritis (PsA). This cross-sectional study, conducted from June 2021 through December 2021, included 763 patients from 11 different centers in Turkey. The severity of involvement was evaluated using psoriasis area severity index (PASI), nail psoriasis severity index (NAPSI), and psoriasis scalp severity index (PSSI) scores. Predictors for PsA were evaluated using univariate and multivariate logistic regression models. PsA (n = 155, 21.5%) was significantly more common in patients having a family history of psoriasis (43.2% vs 30.9%, P = .004), nail involvement (68.4% vs 52.3%, P < .001), and coexistence of nail and scalp involvement (53.7% vs 39.6%, P = .002). Furthermore, patients with PsA had considerably higher PASI (7 vs 5.6, P = .006), NAPSI (5 vs 2, P < .001), and PSSI scores (7 vs 4, P = .002) and longer disease duration (months) (126 vs 108, P = .009). In multivariate analysis, female gender [OR: 3.01, 95% CI (1.861-4.880), P < .001], nail involvement [OR: 2.06, 95% CI (1.293-3.302), P = .002)], and body mass index (BMI) [OR: 1.06, 95% CI (1.017-1.100), P = .005] were identified as independent predictors for PsA. Female gender, nail involvement, and high BMI are significant predictors for PsA and warrant detailed rheumatological assessment. Notably, being female is the strongest predictor of increased risk of PsA in our survey. Scalp involvement appears not to be associated with PsA. Also, the presence of PsA seems related to a more severe skin involvement phenotype.

Psoriatic arthritis risk in psoriasis patients prescribed acitretin versus disease-modifying antirheumatic drugs: a nationwide cohort study

OBJECTIVES

To compare the risk of PsA in psoriasis (PsO) patients treated with acitretin vs DMARDs.

METHODS

This retrospective study used Taiwan's National Health Insurance Research Database from 1997 to 2013. Adult PsO patients without PsA prescribed acitretin or DMARDs for ≥30 days within a year were assigned to the acitretin cohort or DMARDs cohort, respectively. Patients in the acitretin cohort prescribed DMARDs for >7 days, or in the DMARDs cohort prescribed acitretin for >7 days, were excluded. Cumulative incidence of PsA were determined within both cohorts using the Kaplan-Meier method. The hazard ratio (HR) comparing acitretin to DMARDs was calculated with Cox regression models, adjusting for demographic and clinical covariates including the use of NSAIDs and comorbidities.

RESULTS

The study included 1948 patients in each cohort. The 5-year cumulative incidence of PsA in the acitretin cohort was lower than that in the reference cohort (7.52% vs 9.93%; P = 0.005), with a more pronounced difference in the subpopulation receiving NSAIDs treatment. However, in subpopulations without NSAIDs treatment, the 5-year cumulative incidence of PsA in the acitretin cohort was comparable to the DMARDs cohort (5.26% vs 6.98%; P = 0.106). Acitretin was not associated with PsA development in PsO (HR 0.83, 95% confidence interval 0.65-1.05). This risk remained consistent regardless of adjustments for NSAID treatment and comorbidities. Other independent risk factors for PsA included female and NSAIDs treatment.

CONCLUSION

Compared with DMARDs, acitretin was not associated with increased PsA risk in PsO patients.

Matching between ctlinical examination and dermoscopy in patients with nail psoriasis: Should dermoscopy be used instead of clinical examination?

Background

Dermoscopy has emerged as a useful diagnostic tool to evaluate skin lesions, including psoriasis. We aimed to compare the clinical examination and digital dermoscopy findings of nail involvement in patients with psoriatic nails.

Methods

This study included 60 patients with clinically diagnosed psoriasis. The nail findings and NAPSI were evaluated clinically and via dermoscopy, and then the severity of the disease was calculated using PASI criteria.

Results

About 32 patients were males, with a median PASI score of 4.4, and pitting and subungual hyperkeratosis were the most common findings. The clinical and dermoscopic examination had a moderate diagnostic resemblance regarding onycholysis, subungual hyperkeratosis, and leukonychia. The resemblance between the two methods for the diagnosis of leukonychia in patients with a duration of disease <2 years (Kappa = 0.59) and 2-6 years was moderate (Kappa = 0.48), and for 6 years< was perfect (Kappa = 0.62). The resemblance for the diagnosis of subungual hyperkeratosis and onycholysis in subjects with a duration of disease <2 years was slight, and for 2-6 years and 6 years< were moderate. The resemblance between the NAPSI score by the two methods was also moderate (95%CI -0.89-0.81, P < 0.001).

Conclusion

Dermoscopy is an efficient, supportive, and non-invasive method providing a better diagnosis of nail psoriasis.

Guselkumab in Patients with Scalp Psoriasis: A post hoc Analysis of the VOYAGE 2 Phase III Randomized Clinical Trial

Scalp psoriasis affects approximately 80% of patients with psoriasis and can negatively impact their quality of life. This post hoc analysis of the VOYAGE 2 Phase III randomized clinical trial evaluated scalp response to guselkumab treatment and its association with skin response and patient-reported outcomes. The study included patients with moderate-to-severe plaque psoriasis and baseline scalp psoriasis who were initially randomized to receive guselkumab. Patients were divided into 3 groups based on their achievement of a Psoriasis Area and Severity Index 90 response at week 28: responder continuation, non-responder continuation and responder withdrawal. In all 3 groups, mean Psoriasis Area and Severity Index head and scalp-specific Investigator's Global Assessment scores improved through week 28. In the responder withdrawal group, these scores worsened after treatment withdrawal at week 28, but remained stable through week 48 in both continuation groups. Trends in Dermatology Life Quality Index and Psoriasis Symptoms and Signs Diary itch scores mirrored those of mean scalp-specific Investigator's Global Assessment scores through week 48. Within-subject correlations were 0.83 between scalp-specific Investigator's Global Assessment and Psoriasis Area and Severity Index head scores and 0.78 between scalp-specific Investigator's Global Assessment and Psoriasis Symptoms and Signs Diary itch scores. Through week 252, Psoriasis Area and Severity Index head scores remained stable in the responder continuation group, improved in the non-responder continuation group and rapidly improved by week 84 in the responder withdrawal group after retreatment.

Network meta-analyses comparing the efficacy of biologic treatments for achieving complete resolution of nail psoriasis at 24-28 and 48-52 weeks

BACKGROUND

Available network meta-analyses (NMAs) comparing the efficacy of biologics in nail psoriasis (NP) have not included recently approved biologics such as bimekizumab nor have they provided comparisons up to 1 year.

OBJECTIVE

We conducted two NMAs that update and extend results from a previous NMA comparing biologics for achieving complete resolution of NP.

METHODS

Bayesian NMAs were performed using a generalized linear model with a logit link to model the binary outcome of nail clearance at weeks 24-28 and 48-52.

RESULTS

For the NMA at weeks 24-28, which included seven biologics and placebo, the absolute probability of achieving complete resolution of NP was highest for ixekizumab (46.4%; 95% credibility interval [CrI] 35.2-58.0), followed by brodalumab (37.1%; 95% CrI 17.1-62.2) and bimekizumab (30.3%; 95% CrI 12.7-53.9). For the NMA at weeks 48-52, which included six biologics, the absolute probability was highest for ixekizumab (77.2%; 95% CrI 51.1-93.4), followed by adalimumab (75.6%; 95% CrI 61.5-87.3) and brodalumab (71.9%; 95% CrI 38.4-93.2).

CONCLUSION

Among biologics included in these two NMAs, ixekizumab has the highest absolute probability of achieving complete resolution of NP. Results may help to inform treatment decisions for patients with NP.

Prevalence and risk factors associated with psoriatic arthritis among patients with psoriasis

INTRODUCTION

Psoriatic arthritis is a chronic, autoimmune inflammatory arthritis that occurs with psoriasis and has profound impact on patients' physical and psychological well-being. This study aims to determine the prevalence and risk factors associated with psoriatic arthritis among patients with psoriasis.

METHODS

A single-center, cross-sectional study was conducted over a 12-month period at the Dermatology Clinic, Hospital Pulau Pinang, Malaysia involving all consecutive psoriasis patients. CASPAR (ClASsification of Psoriatic ARthritis) criteria were used to diagnose psoriatic arthritis.

RESULTS

A total of 360 patients with psoriasis were recruited, of whom 107 (29.7%) had psoriatic arthritis. Psoriatic arthritis patients had equal gender distribution and the mean age of arthritis onset was 40.7 ± 12.8 years. Psoriasis preceded arthritis in 81.3% of patients (n = 87) with a mean latency interval of 10.5 years. Polyarthropathy was the predominant subtype affecting 46.8% (n = 50) of patients, followed by oligoarthropathy (22.4%, n = 24), axial joint disease (5.6%, n = 6), predominant distal interphalangeal joint disease (2.8%, n = 3), and mixed subtype (22.4%, n = 24). Enthesitis and dactylitis occurred in 12.1% (n = 13) and 20.6% (n = 22) of arthritis patients, respectively, and deformity was present in 37.4% (n = 40). Psoriatic arthritis was significantly associated with being an ever smoker (adjusted odds ratio [aOR] 0.41; 95% confidence interval [CI] 0.18-0.91, p = .029), genital psoriasis (aOR 2.25; 95% CI 1.17-4.33, p = .015), and increased erythrocyte sedimentation rate (ESR) (aOR 1.02; 95% CI 1.01-1.04, p = .005) and C-reactive protein [CRP] (aOR 1.04; 95% CI 1.00-1.08, p = .040).

CONCLUSION

Our study showed a high prevalence of psoriatic arthritis among the psoriasis cohort. Genital involvement, and increased ESR and CRP were associated with psoriatic arthritis among patients with psoriasis.

Alterations in the cutaneous microbiome of patients with psoriasis and psoriatic arthritis reveal similarities between non-lesional and lesional skin

OBJECTIVES

To investigate the cutaneous microbiome spanning the entire psoriatic disease spectrum, and to evaluate distinguishing features of psoriasis (PsO) and psoriatic arthritis (PsA).

METHODS

Skin swabs were collected from upper and lower extremities of healthy individuals and patients with PsO and PsA. Psoriatic patients contributed both lesional (L) and contralateral non-lesional (NL) samples. Microbiota were analysed using 16S rRNA sequencing.

RESULTS

Compared with healthy skin, alpha diversity in psoriatic NL and L skin was significantly reduced (p<0.05) and samples clustered separately in plots of beta diversity (p<0.05). Kocuria and Cutibacterium were enriched in healthy subjects, while Staphylococcus was enriched in psoriatic disease. Microbe-microbe association networks revealed a higher degree of similarity between psoriatic NL and L skin compared with healthy skin despite the absence of clinically evident inflammation. Moreover, the relative abundance of Corynebacterium was higher in NL PsA samples compared with NL PsO samples (p<0.05), potentially serving as a biomarker for disease progression.

CONCLUSIONS

These findings show differences in diversity, bacterial composition and microbe-microbe interactions between healthy and psoriatic skin, both L and NL. We further identified bacterial biomarkers that differentiate disease phenotypes, which could potentially aid in predicting the transition from PsO to PsA.

Predicting the Risk of Nail Involvement in Psoriasis Patients: Development and Assessment of a Predictive Nomogram

BACKGROUND

Nail involvement has a tremendous impact on psoriasis patients. Early detection and prompt intervention of psoriatic nail damage are necessary.

METHODS

A total of 4290 patients confirmed to have psoriasis between June 2020 and September 2021 were recruited from the Follow-up Study of Psoriasis database. Among them, 3920 patients were selected and divided into the nail involvement group (n = 929) and the non-nail involvement group (n = 2991) by inclusion and exclusion criteria. Univariate and multivariable logistic regression analyses were performed to identify the predictors of nail involvement for the nomogram. Calibration plots, the receiver operating characteristic (ROC) curve, and decision curve analysis (DCA) were used to evaluate the discriminative and calibrating ability and clinical utility of the nomogram.

RESULTS

Sex, age at onset, duration, smoking, drug allergy history, comorbidity, sub-type of psoriasis, scalp involvement, palmoplantar involvement, genital involvement, and PASI score were selected to establish the nomogram for nail involvement. AUROC (0.745; 95% CI: 0.725-0.765) indicated the satisfactory discriminative ability of the nomogram. The calibration curve showed favorable consistency, and the DCA showed the good clinical utility of the nomogram.

CONCLUSION

A predictive nomogram with good clinical utility was developed to assist clinicians in evaluating the risk of nail involvement in psoriasis patients.

Early intervention in psoriasis: Where do we go from here?

Patients with psoriasis often have comorbidities and are at increased risk of developing several complications compared with the general population. Knowledge on the role of immune mediators and systemic inflammation in psoriasis has led to the hypothesis that early intervention with systemic therapy has the potential to modify the course of the disease and reduce the risk of long-term adverse outcomes. In this article, we address some potential issues that need to be considered before early intervention can be implemented routinely. The first is determining what constitutes "early" intervention for psoriasis. A second point is whether the intervention should be considered for patients with early disease or for selected subsets based on risk stratification. A third important consideration is defining success for early intervention. Finally, adoption of early and effective intervention should be based on high-level evidence. Ideally, randomized trials would be the best strategy to compare early vs. late systemic treatment in patients with psoriasis, probably using the frequency of long-term outcomes as primary endpoint, with cutaneous and pharmacoeconomic outcomes assessed secondarily.

Do Patients with Psoriatic Arthritis Have More Severe Skin Disease than Patients with Psoriasis Only? A Systematic Review and Meta-Analysis

BACKGROUND

Early identification of patients at risk of psoriatic arthritis (PsA) is essential to facilitate early diagnosis and improve clinical outcomes. Severe cutaneous psoriasis has been proposed to be associated with PsA, but a recent assessment of the evidence is lacking. Therefore, in this systematic review, we address the association of psoriasis skin severity with the presence and development of PsA.

SUMMARY

We included articles from a review published in 2014 and supplemented these with recent literature by performing an additional systematic search to identify studies published between 1 January 2013 and 11 February 2021. A meta-analysis was performed when sufficient comparable evidence was available. Of 2,000 screened articles, we included 29 in the analysis, of which 16 were identified by our updated search. Nineteen studies reported psoriasis severity as psoriasis area and severity index (PASI), ten studies as body surface area (BSA), and two studies as "number of affected sites." Most studies show that more extensive skin disease is associated with the presence of PsA. The quantitative pooled analyses demonstrate higher PASI (mean difference [Δ] 1.59; 95% confidence interval [CI] 0.29-2.89) and higher BSA (Δ 5.31; 95% CI 1.78-8.83) in patients with PsA as compared to psoriasis patients without PsA. Results from prospective studies - that assess the risk of future development of PsA in psoriasis patients - were inconclusive.

KEY MESSAGES

In patients with psoriasis, more severe skin involvement is associated with the presence of PsA, underpinning the importance of optimal dermatology-rheumatology collaboration in clinical care. There are insufficient data to support the use of psoriasis skin severity to predict the future development of PsA in psoriasis patients.

Predicting the Risk of Psoriatic Arthritis in Plaque Psoriasis Patients: Development and Assessment of a New Predictive Nomogram

Objective

This study aimed to develop a risk of psoriatic arthritis (PsA) predictive model for plaque psoriasis patients based on the available features.

Methods

Patients with plaque psoriasis or PsA were recruited. The characteristics, skin lesions, and nail clinical manifestations of the patients have been collected. The least absolute shrinkage was used to optimize feature selection, and logistic regression analysis was applied to further select features and build a PsA risk predictive model. Calibration, discrimination, and clinical utility of the prediction model were evaluated by using the calibration plot, C-index, the area under the curve (AUC), and decision curve analysis. Internal validation was performed using bootstrapping validation. The model was subjected to external validation with two separate cohorts.

Results

Age at onset, duration, nail involvement, erythematous lunula, onychorrhexis, oil drop, and subungual hyperkeratosis were presented as predictors to perform the prediction nomogram. The predictive model showed good calibration and discrimination (C-index: 0.759; 95% CI: 0.707–0.811). The AUC of this prediction model was 0.7578092. Excellent performances of the C-index were reached in the internal validation and external cohort validation (0.741, 0.844, and 0.845). The decision curve indicated good effect of the PsA nomogram in guiding clinical practice.

Conclusion

This novel PsA nomogram could assess the risk of PsA in plaque psoriasis patients with good efficiency.

Psoriasis to Psoriatic Arthritis: The Application of Proteomics Technologies

Psoriatic disease (PsD) is a spectrum of diseases that affect both skin [cutaneous psoriasis (PsC)] and musculoskeletal features [psoriatic arthritis (PsA)]. A considerable number of patients with PsC have asymptomatic synovio-entheseal inflammations, and approximately one-third of those eventually progress to PsA with an enigmatic mechanism. Published studies have shown that early interventions to the very early-stage PsA would effectively prevent substantial bone destructions or deformities, suggesting an unmet goal for exploring early PsA biomarkers. The emergence of proteomics technologies brings a complete view of all involved proteins in PsA transitions, offers a unique chance to map all potential peptides, and allows a direct head-to-head comparison of interaction pathways in PsC and PsA. This review summarized the latest development of proteomics technologies, highlighted its application in PsA biomarker discovery, and discussed the possible clinical detectable PsA risk factors in patients with PsC.

Clinical, laboratory, and genetic markers for the development or presence of psoriatic arthritis in psoriasis patients: a systematic review

Twenty to thirty percent of psoriasis (Pso) patients will develop psoriatic arthritis (PsA). Detection of Pso patients that are (at risk for) developing PsA is essential to prevent structural damage. We conducted a systematic search of five bibliographic databases, up to May 2020. We searched for studies assessing markers (clinical, laboratory, genetic) associated with the development or presence of PsA in Pso patients. Study selection and quality assessment of the included studies was performed, followed by a qualitative best evidence synthesis to determine the level of evidence for a marker and its association with concomitant/developing PsA in Pso. Overall, 259 possible markers were identified in 119 studies that met the inclusion criteria. Laboratory markers related to inflammation and bone metabolism reached a strong level of evidence for the association (not prediction) of PsA in Pso. Only CXCL10 showed strong evidence for a positive predictive value for PsA in Pso. The importance of timely detecting PsA in a Pso population, and finding more (bio)markers contributing to early detection, remains high.

Large-Scale Imputation of KIR Copy Number and HLA Alleles in North American and European Psoriasis Case-Control Cohorts Reveals Association of Inhibitory KIR2DL2 With Psoriasis

Killer cell immunoglobulin-like receptors (KIR) regulate immune responses in NK and CD8+ T cells via interaction with HLA ligands. KIR genes, including KIR2DS1, KIR3DL1, and KIR3DS1 have previously been implicated in psoriasis susceptibility. However, these previous studies were constrained to small sample sizes, in part due to the time and expense required for direct genotyping of KIR genes. Here, we implemented KIR*IMP to impute KIR copy number from single-nucleotide polymorphisms (SNPs) on chromosome 19 in the discovery cohort (n=11,912) from the PAGE consortium, University of California San Francisco, and the University of Dundee, and in a replication cohort (n=66,357) from Kaiser Permanente Northern California. Stratified multivariate logistic regression that accounted for patient ancestry and high-risk HLA alleles revealed that KIR2DL2 copy number was significantly associated with psoriasis in the discovery cohort (p ≤ 0.05). The KIR2DL2 copy number association was replicated in the Kaiser Permanente replication cohort. This is the first reported association of KIR2DL2 copy number with psoriasis and highlights the importance of KIR genetics in the pathogenesis of psoriasis.

Pain Management in Painful Psoriasis and Psoriatic Arthropathy: Challenging and Intricately Intertwined Issues Involving Several Systems

PURPOSE OF REVIEW

Psoriasis and psoriatic arthropathy are inflammatory autoimmune conditions that can lead to profound emotional distress, social stigmatization, isolation, disfigurement, pain, disability, unemployment, and decreased quality of life. Thus, this disease has immense psychological, social, and economic implications as the pain experienced is closely associated with the primary disease burden. This review focuses on discussing the primary disease burden of psoriasis and psoriatic arthropathy, as well as management of different types of pain in these patients.

RECENT FINDINGS

Pain affects over 40% of patients with psoriasis, ranging from neuropathic to nociceptive. Treatment of pain largely focuses on treating the underlying disease with mild topical steroids and non-steroidal medications including vitamin D analogs followed by systemic immunomodulatory agents for more severe disease. Interventional options such as corticosteroid injections are available for select cases (conditional recommendation). Psoriasis and psoriatic arthropathy have been associated with underreporting and resultant undertreatment of pain. Pain control in these conditions is complex and requires a multidisciplinary approach. More research and guidelines are needed in the areas of reporting of psoriatic disease, associated pain, psoriatic nociception, and optimal clinical management.

Impact of smoking on psoriasis risk and treatment efficacy: a meta-analysis

Objective

Psoriasis is an immune-mediated chronic inflammatory disease with skin and joint manifestations. Smoking is considered an unfavorable lifestyle factor for psoriasis. We aimed to explore the association between smoking, disease risk, and treatment efficacy in relation to psoriasis.

Methods

We searched the Cochrane Library, Embase, and PubMed databases for studies examining the relationship between smoking and psoriasis, up to 12 April 2020. We then conducted a meta-analysis using a fixed-effects model to obtain odds ratios (ORs) with 95% confidence intervals (CIs).

Results

Ever, current, and former smokers all had higher risks of developing psoriasis than non-smokers (pooled ORs (95% CIs): 1.60 (1.51–1.69), 1.63 (1.48–1.80), and 1.36 (1.13–1.64), respectively). Ever smokers were less likely to show disease improvement at 6 months following treatment with biologic agents than non-smokers (pooled OR (95% CI): 0.80 (0.67–0.95)).

Conclusions

Smoking increases psoriasis risk and negatively impacts the benefits of biologic agents. However, the number of reports is limited and more studies are needed to confirm the effects of smoking and smoking cessation on therapeutic response in patients with psoriasis. Education to encourage a healthy lifestyle remains a valuable approach in clinical practice.

Association of Nail Psoriasis With Disease Activity Measures and Impact in Psoriatic Arthritis: Data From the Corrona Psoriatic Arthritis/Spondyloarthritis Registry

OBJECTIVE

To examine the association of nail psoriasis with disease activity, quality of life, and work productivity in patients with psoriatic arthritis (PsA).

METHODS

All patients with PsA who enrolled in the Corrona PsA/Spondyloarthritis Registry between March 2013 and October 2018 and had data on physician-reported nail psoriasis were included and stratified by presence vs absence of nail psoriasis at enrollment. Patient demographics, disease activity, quality of life (QOL), and work productivity at enrollment were compared between patients with vs without nail psoriasis using t-tests or Wilcoxon rank-sum tests for continuous variables and chi-square or Fisher exact tests for categorical variables.

RESULTS

Of the 2841 patients with PsA included, 1152 (40.5%) had nail psoriasis and 1689 (59.5%) did not. Higher proportions of patients with nail psoriasis were male (51.9% vs 44.1%) and disabled from working (12.3% vs 7.8%) compared with patients without nail psoriasis (all P < 0.05). Patients with nail psoriasis had higher disease activity than those without nail psoriasis, including higher tender and swollen joint counts, worse Disease Activity Index for Psoriatic Arthritis and Psoriatic Arthritis Disease Activity Score values, and increased likelihood of having enthesitis and dactylitis (all P < 0.05). Patients with nail psoriasis had worse pain, fatigue, and work and activity impairment than those without nail psoriasis (all P < 0.05).

CONCLUSION

Patients with PsA who have nail psoriasis had worse disease activity, QOL, and work productivity than those without nail involvement, emphasizing the importance of identification and management of nail disease in patients with PsA.

Clinical, Serological and Immunological Characteristics in Greek Patients with Psoriatic Arthritis: The Role of IL-17, IL-23, and Sclerostin

Psoriatic arthritis (PsA) is an inflammatory form of arthritis that belongs to the family of spondyloarthritis (SpA) and is related to skin psoriasis. The incidence and prevalence of the disease vary considerably between countries. PsA is classified into axial PsA and peripheral PsA, with a wide range of other extra-articular manifestations. Although the aetiology of the disease is unknown, genetic, environmental, and immunologic factors appear to affect its appearance. In recent years, the role of the immune system in the pathogenesis of PsA has been increasingly investigated. Specific cytokines such as tumour necrosis factor (TNF), interleukin (IL-) 17 and IL-23, play an essential role affecting joint structures. This observation led to the emergence of tumour necrosis factor inhibitors (TNFi) that offer considerable therapeutic benefit to PsA patients. However, chronic inflammation causes bone loss, while new bone formation may also occur in both peripheral and axial skeleton. The molecular mechanisms underlying these processes have not yet been fully understood. So far, the role of the Wnt/β-catenin pathway and its inhibitors (Dickkopf and sclerostin) has been evaluated in ankylosing spondylitis (AS), but in PsA has not been studied sufficiently. The present study aims to investigate the epidemiological characteristics and clinical features (articular and extra-articular manifestations) as well as the treatment of PsA patients in the region of northwestern (NW) Greece. It also aims to evaluate the role of specific cytokines and sclerostin in patients with PsA, giving evidence to possible future biomarkers or even therapeutic targets for the disease.

The impact of smoking on prevalence of psoriasis and psoriatic arthritis

Objectives

In this systematic literature review and meta-analysis, we aimed to investigate the impact of cigarette smoking on the prevalence and incidence of psoriasis and psoriatic arthritis (PsA).

Method

We performed a systematic literature review using the MEDLINE, EMBASE and Cochrane Central Register databases. The literature included publications from January 1980 to July 2019. The studies that provided clear information on the number of patients with ever smoking data were included in the meta-analysis.

Results

The systematic literature review identified 52 and 24 articles for the prevalence of smoking in psoriasis and PsA, respectively. Of these, 16 articles on psoriasis and three and four (general population and psoriasis, respectively) articles on PsA met the criteria and were included in the meta-analysis. The prevalence of ever smoking was increased in psoriasis compared with the general population (OR: 1.84; 95% CI: 1.4, 2.3). For PsA the prevalence of ever smoking was reduced in psoriasis patients (OR: 0.70; 95% CI: 0.60, 0.81), but not changed compared with the general population (OR: 1.10; 95% CI: 0.92, 1.32).

Conclusion

This meta-analysis showed that ever smoking increases the risk of psoriasis in the general population, but may reduce the risk of PsA in psoriasis patients. The latter may be also due to the collider effect. Whether smoking cessation neutralizes the risk of developing psoriasis requires a well-defined smoking data collection for the past history and this is currently unavailable in the literature.

Evaluation of a Genetic Risk Score for Diagnosis of Psoriatic Arthritis

Background

Diagnosis of psoriatic arthritis (PsA) can be challenging, resulting in delays that contribute to irreversible joint damage, reduced quality of life, and increased mortality.

Objective

Use genetic markers to develop and evaluate a PsA genetic risk score (GRS) for its ability to discriminate between psoriasis (PsO) only and PsO with PsA among a psoriatic cohort with full genome-wide genotype data.

Methods

Genome-wide single-nucleotide polymorphism genotyping was performed on 724 psoriatic patients. A set of 11 candidate risk genes previously shown to be preferentially associated with PsO or PsA were selected. To evaluate the cumulative effects of these risk loci, a PsA GRS was developed using an unweighted risk allele count (cGRS) and a weighted (wGRS) approach. Additional analyses included only human leukocyte antigen (HLA) risk alleles.

Results

The discriminative power attributable to each GRS was evaluated by calculating the areas under the receiver operator characteristic curve (AUROC). The AUROC for the wGRS is 56.2% versus 54.1% for the cGRS, and the AUROC for the HLA-only wGRS model was 56.9% versus 55.7% for the HLA-only cGRS.

Conclusion

The AUROC of 56.9% for HLA-only wGRS indicates that this approach has the greatest power in discriminating PsA from PsO among these models. Given that an AUROC of 56.9% is quite modest, this study suggests that using a small number of well-validated genetic loci provides limited predictive power for PsA, and that future approaches may benefit from using a larger number of genetic loci.