Psoriatic disease: concepts and implications

Systematic literature review of non-topical treatments for early, untreated (systemic therapy naïve) psoriatic disease: a GRAPPA initiative

Background

Psoriatic disease (PsD) is a complex systemic disorder with cutaneous and musculoskeletal manifestations. Current evidence on pharmacological interventions, effective across the spectrum of clinical manifestations of early, systemic treatment-naïve PsD, is limited. This review aims to appraise such evidence.

Methods

This systematic review examined seven patient-intervention-comparator-outcome research questions to address the efficacy of the interventions on the following: across the spectrum of clinical manifestations PsD activity; peripheral arthritis; dactylitis; spondylitis; enthesitis; skin; and nails. Early PsD was defined as a disease duration of ≤2 years, except for studies investigating outcomes restricted to the skin. Eligible references were clinical trials or well-designed prospective studies/series reporting on adult humans, untreated, with cutaneous and/or musculoskeletal features of PsD.

Results

Nine references (out of 160 319, publication range 1946-2019) fulfilled the eligibility criteria. No study adopted comprehensive (that is, simultaneous assessment of different PsD manifestations) composite indices as primary outcome measures. Individual studies reported that apremilast and biologics successfully improved outcomes (disease activity index for PsA, minimal disease activity, PsA DAS, psoriasis area and severity index, PsA response criteria) when efficacy analyses were restricted to single manifestations of untreated PsD. Only qualitative synthesis of evidence was possible, owing to the following factors: data heterogeneity (disease classification criteria, outcome measures); unavailable data subsets (focused on early, untreated PsD) at the single study level; and insufficient data on the exposure of participants to previous treatment.

Conclusion

Effective interventions, albeit limited in scope, were found for early, treatment-naïve PsD. No study provided evidence about the management of co-occurring cutaneous and musculoskeletal manifestations in early, treatment-naïve PsD. This review highlights an unmet need in research on early PsD.

Psoriasis and Connective Tissue Diseases

Psoriasis is a chronic systemic inflammatory disease with various co-morbidities, having been recently considered as a comprehensive disease named psoriatic disease or psoriatic syndrome. Autoimmune diseases are one form of its co-morbidities. In addition to the genetic background, shared pathogenesis including innate immunity, neutrophil extracellular trap (NETs), and type I interferon, as well as acquitted immunity such as T helper-17 (Th17) related cytokines are speculated to play a significant role in both psoriasis and connective tissue diseases. On the other hand, there are definite differences between psoriasis and connective tissue diseases, such as their pathomechanisms and response to drugs. Therefore, we cannot expect that one stone kills two birds, and thus caution is necessary when considering whether the administered drug for one disease is effective or not for another disease. In this review, several connective tissue diseases and related diseases are discussed from the viewpoint of their coexistence with psoriasis.

The Protein Tyrosine Phosphatase Nonreceptor 22 (PTPN22) R620W Functional Polymorphism in Psoriasis

Background:

Psoriasis is a complex autoimmune disease caused by the interaction of genetic and environmental factors. PTPN22 gene polymorphism has been reported to affect psoriasis susceptibility; however, no data are available for Middle Eastern populations.

Objective:

The aim of this study was to investigate the association of PTPN22 (1858C/T) R620W polymorphism with psoriasis in a Saudi cohort.

Methods:

Saudi subjects (n = 306) including patients with psoriasis (n = 106) and matched controls (n = 200) were studied for PTPN22 variants using tetra-primer amplification refractory mutation system-polymerase chain reaction method. The frequencies of alleles and genotypes of PTPN22 (1858C/T) polymorphism were compared between patients and controls.

Results:

The frequency of CT genotype of PTPN22 (1858C/T) polymorphism was significantly higher, whereas that of CC genotype was lower in patients with psoriasis than in controls (P < .001, relative risk [RR] = 7.151). The homozygous genotype TT was absent in both the patients and healthy controls. The frequency of allele T encoding tryptophan (W) was significantly increased (P < .001, RR = 5.76), whereas that of allele C encoding arginine (R) decreased in psoriasis cases as compared with controls (P < .001, RR = 0.173) indicating that individuals carrying allele T are more susceptible to psoriasis than noncarriers.

Conclusions:

PTPN22 (1858C/T) polymorphism is positively associated with susceptibility of psoriasis in Saudis and can be developed as biomarker for evaluating psoriasis risk. However, further studies on PTPN22 polymorphism in larger samples from different geographical areas and ethnicity are warranted.

Urine metabolome profiling of immune-mediated inflammatory diseases

BACKGROUND

Immune-mediated inflammatory diseases (IMIDs) are a group of complex and prevalent diseases where disease diagnostic and activity monitoring is highly challenging. The determination of the metabolite profiles of biological samples is becoming a powerful approach to identify new biomarkers of clinical utility. In order to identify new metabolite biomarkers of diagnosis and disease activity, we have performed the first large-scale profiling of the urine metabolome of the six most prevalent IMIDs: rheumatoid arthritis, psoriatic arthritis, psoriasis, systemic lupus erythematosus, Crohn's disease, and ulcerative colitis.

METHODS

Using nuclear magnetic resonance, we analyzed the urine metabolome in a discovery cohort of 1210 patients and 100 controls. Within each IMID, two patient subgroups were recruited representing extreme disease activity (very high vs. very low). Metabolite association analysis with disease diagnosis and disease activity was performed using multivariate linear regression in order to control for the effects of clinical, epidemiological, or technical variability. After multiple test correction, the most significant metabolite biomarkers were validated in an independent cohort of 1200 patients and 200 controls.

RESULTS

In the discovery cohort, we identified 28 significant associations between urine metabolite levels and disease diagnosis and three significant metabolite associations with disease activity (P FDR < 0.05). Using the validation cohort, we validated 26 of the diagnostic associations and all three metabolite associations with disease activity (P FDR < 0.05). Combining all diagnostic biomarkers using multivariate classifiers we obtained a good disease prediction accuracy in all IMIDs and particularly high in inflammatory bowel diseases. Several of the associated metabolites were found to be commonly altered in multiple IMIDs, some of which can be considered as hub biomarkers. The analysis of the metabolic reactions connecting the IMID-associated metabolites showed an over-representation of citric acid cycle, phenylalanine, and glycine-serine metabolism pathways.

CONCLUSIONS

This study shows that urine is a source of biomarkers of clinical utility in IMIDs. We have found that IMIDs show similar metabolic changes, particularly between clinically similar diseases and we have found, for the first time, the presence of hub metabolites. These findings represent an important step in the development of more efficient and less invasive diagnostic and disease monitoring methods in IMIDs.

Impact of 24-month treatment with etanercept, adalimumab, or methotrexate on metabolic syndrome components in a cohort of 210 psoriatic arthritis patients

Psoriatic arthritis (PsA) is a chronic inflammatory condition, characterized by an excess of metabolic disorders. Metabolic syndrome (MetS) is a cluster of classic cardiovascular risk factors, due to an imbalance between pro- and anti-inflammatory adipokines. Tumor necrosis factor (TNF)-α is a pro-inflammatory adipocytokine mainly produced by monocytes and macrophages with a central role in inflammatory responses, but it also induces adipocytes apoptosis, promotes insulin resistance, and stimulates lipolysis. The aim of this study was to evaluate the impact of therapy with etanercept (ETN), adalimumab (ADA), and methotrexate (MTX) on MetS components in a cohort of PsA patients with a follow-up period of 24 months. A retrospective study has been conducted in a cohort of PsA patients. On the basis of the inclusion criteria, we identified the first 70 consecutive patients, respectively, on ADA, ETN, and MTX, for a total of 210 patients achieving PsARC criteria during the observation period. As part of the routine clinical practice, assessment of metabolic parameters and of disease activity was recorded at baseline (T0), at 12 months (T1), and at 24 months (T2). The results show that when the specific components of the MetS were considered, taking also into account by regression analysis the effect of the confounding factors, the patients on etN and ADA show a significant improvement of the metabolic syndrome components (in detail, waist circumference, triglycerides, high-density lipoprotein cholesterol, and glucose) as compared to the MTX group. In conclusion, these data suggest that the biologic treatment in PsA can no longer be taken into consideration only for its positive effect on articular and cutaneous symptoms but also on the various aspects of this complex picture.

Serum kallikrein-8 correlates with skin activity, but not psoriatic arthritis, in patients with psoriatic disease

BACKGROUND

About 30% of cutaneous psoriasis (PsC) patients develop psoriatic arthritis (PsA) in the joint, which is under-recognized by dermatologists. Biomarkers for PsA are needed so that early referral to a rheumatologist is made. Kallikreins (KLKs) are secreted serine proteases implicated in skin desquamation and inflammation. This study examined KLK potential as serum biomarkers of PsA in cutaneous psoriasis patients.

METHODS

KLKs were measured by ELISAs in synovial fluids of three PsA patients and three control early osteoarthritis (OA) patients, as well as in a cohort of 152 serum samples collected from age- and sex-matched PsC patients, with (n=76) or without PsA (n=76). KLK expression in psoriatic plaques was examined by immunohistochemistry. Univariate and multivariate logistic regression analyses were conducted to analyze the association between serum KLK levels and disease class (PsC, PsA). Serum KLKs that associated with PsA were correlated with clinical parameters of skin and joint activity.

RESULTS

Among the seven KLKs tested, KLK6 and KLK8 were elevated in both PsA synovial fluids and psoriatic plaques, but only serum KLK8 levels were associated with psoriatic disease (odds ratio=2.56, p=0.03). Although significantly elevated in PsC and PsA sera compared to healthy controls, KLK8 did not discriminate PsA from PsC patients. KLK8 correlated positively with the psoriasis area and severity index (PASI) (r=0.43, p=0.001) independent of age, sex and psoriasis duration ( β=1.153, p=0.0003) and exhibited no correlations with tender or swollen joint counts.

CONCLUSIONS

Increased KLK8 serum level in PsA patients reflects disease activity in the skin but not in the joints. Serum KLK levels are not useful for screening psoriasis patients for PsA.

Anterior Chest Wall Involvement in Early Stages of Spondyloarthritis: Advanced Diagnostic Tools

Objective.

Anterior chest wall (ACW) involvement is difficult to evaluate in patients with spondyloarthritis (SpA). Bone scan is sensitive to ACW involvement, while magnetic resonance imaging (MRI) detects early alterations in SpA. We compared the sensitivity and specificity of bone scans and MRI in assessing ACW in early SpA.

Methods.

Out of 110 patients with early SpA attending the Outpatient Rheumatology Unit Clinic of Padua University from January 2008 to December 2010, the 40 complaining of pain and/or tenderness [60% with psoriatic arthritis (PsA), 12.5% with ankylosing spondylitis, and 27.5% with undifferentiated SpA] underwent bone scans and MRI.

Results.

At clinical examination, sternocostoclavicular joints were involved in 87.5% on the right, 77.5% on the left, and 35% on the sternum. Bone scan was positive in 100% and MRI in 62.5% of these patients. Early MRI signs (bone edema, synovial hyperemia) were observed in 27.5%, swelling in 5%, capsular structure thickness in 37.5%, erosions in 15%, bone irregularities in 15%, osteoproductive processes in 12.5%, and osteophytes in 5%. A higher prevalence of Cw6, Cw7, B35, and B38 was found in 15%, 48%, 28%, and 12%, respectively, of the patients with PsA who had bone scans.

Conclusion.

Noted mainly in women, ACW involvement was frequent in early SpA. Both bone scans and MRI are useful in investigating ACW inflammation. Bone scans were found to have high sensitivity in revealing subclinical involvement, but a low specificity. MRI provides useful information for therapeutic decision making because it reveals the type and extent of the process. The significant associations of HLA-Cw6 and Cw7 with PsA could suggest that genetic factors influence ACW involvement.

Predictors of Early Minimal Disease Activity in Patients with Psoriatic Arthritis Treated with Tumor Necrosis Factor-α Blockers

Objective.

To identify predictors of early minimal disease activity in patients with psoriatic arthritis (PsA) receiving tumor necrosis factor-α (TNF-α) antagonists.

Methods.

In total 146 consecutive patients with PsA eligible for anti-TNF-α therapy were enrolled. At baseline (T0) information about age, sex, PsA subset, disease duration, comorbidities, and treatments was collected. All subjects were tested for metabolic syndrome (MetS) and/or liver steatosis. A clinical and laboratory evaluation was performed at T0 and at 3 months (T3). Changes in all these variables were compared in subjects achieving minimal disease activity (MDA) and those who did not.

Results.

Among 146 PsA subjects, 10 discontinued therapy before 3-month followup because of adverse events; thus 136 concluded the study. All clinical outcome measures changed significantly from T0 to T3. Erythrocyte sedimentation rate showed a significant reduction (p < 0.001). C-reactive protein (CRP), serum cholesterol, and triglycerides showed no significant variation (p > 0.05). The prevalence of MetS and liver steatosis showed no significant differences between subjects achieving MDA and those who did not (p = 0.347 and 0.053, respectively). Patients achieving MDA at T3 were younger than those not achieving MDA (p = 0.001). A lower baseline tender joint count (p = 0.001), swollen joint count (p = 0.013), Bath Ankylosing Spondylitis Disease Activity Index (p = 0.021), and Ritchie index (p = 0.006) were found in subjects achieving MDA. Age (OR 0.896, p = 0.003) and Bath Ankylosing Spondylitis Functional Index (BASFI) (OR 0.479, p = 0.007) inversely predicted, whereas CRP (OR 1.78, p = 0.018) directly predicted, achievement of MDA at T3.

Conclusion.

In patients with PsA, age, CRP, and BASFI at the beginning of treatment were found to be reliable predictors of MDA after 3 months of TNF-α blocker therapy.

Psoriatic arthritis is associated with increased arterial stiffness in the absence of known cardiovascular risk factors: a case control study

The objective of the study was the evaluation of arterial stiffness, a cardiovascular risk factor, in patients with psoriatic arthritis (PsA). Twenty PsA patients classified on the basis of the CASPAR criteria (M/W, 14/6; mean age, 38.6 years; range, 22-53), attending our out-patient clinic, and 20 healthy control subjects (M/W, 14/6; mean age, 38.7 years; range, 22-53) matched for age, weight, height and with similar cardiometabolic profile entered the study. An exclusion criterion was the presence of known cardiovascular risk factors. Central hemodynamic parameters and aortic pulse wave velocity (aPWV) were assessed non-invasively by a SphygmoCor device. A significantly higher aPWV was recorded in PsA patients when compared to controls. The difference remained statistically significant after adjustment for age, weight, height, heart rate (HR) and central mean pressure (mean±SE; PsA, 8.3 ± 0.2 versus control, 6.8 ± 0.2 m/s; p < 0.0001). Among PsA patients, aPWV was related to known duration of disease (r = 0.63; p = 0.003). This result was confirmed after adjustment for the main confounders (β = 0.011; p = 0.013). These results support the concept of psoriatic disease as a systemic condition involving not only the skin, joints and gastrointestinal tract but also arterial vessels. The involvement of the vascular system indicates the presence of pathogenetic mechanisms that could accelerate the atherosclerotic process in this condition.

Clastogenic plasma factors in psoriasis--comparison of phototherapy and anti-TNF-α treatments

As previously described, Psoralen plus UVA (PUVA) therapy induces chromosome damage in psoriatic patients. This study evaluates whether these effects are transitory or persistent. In addition, we studied these effects after narrowband UVB (nUVB) and anti-tumor necrosis factor (TNF)-α treatments. Among 40 responder patients, 10 received PUVA, 10 nUVB, 10 Infliximab and 10 Etanercept. Disease activity was determined with Psoriasis Area and Severity Index. Chromosomal breakage was evaluated by the clastogenic factor (CF) test. Potential clastogenic agents, malondialdehyde (MDA) and TNF-α were measured. Before treatment, the plasma-adjusted clastogenic scores (ACS) of patients were increased. During treatment, a further increase in ACS was observed in both phototherapy groups. Chromosome damage persisted for PUVA patients at week 32, while it diminished after nUVB to ACS values lower than before treatment. MDA and TNF-α values were also increased at baseline. MDA decreased during treatment in all groups, but without reaching normal levels. Plasma TNF-α remained unchanged in PUVA and nUVB but decreased in both anti-TNF-α treatment groups. Psoriasis is accompanied by CF-induced chromosomal breakage that increases during PUVA and nUVB treatments. Plasma clastogenic activity persisted in the follow-up after PUVA, while after nUVB ACS returned to values even lower than baseline. Clastogenic activity during the induction phase with anti-TNF-α remained unchanged.