Itch: an under-recognized problem in psoriasis

Burden of impaired sleep and its improvement through topical treatment in psoriasis and atopic dermatitis

INTRODUCTION

Patients with chronic inflammatory skin diseases often suffer from sleep disturbances. However, objective data on sleep architecture, especially to evaluate potential overall influences under therapy, are lacking.

PATIENTS AND METHODS

Pilot study on sleep quality changes including psoriasis and atopic dermatitis patients before and 2 weeks after intensive topical treatment. In addition to disease activity rating, patient-rated outcomes for itch severity and sleep quality and polygraphy was performed before and after topical therapy.

RESULTS

14 psoriasis, eleven atopic dermatitis patients (10 female, 15 male) with a mean age of 49 years were included. Disease activity scores (EASI and PASI) were significantly reduced with topical therapy after 2 weeks (p < 0.001). Pruritus intensity (NRS) showed a significant influence on deep sleep, which resolved after therapy. Insomnia severity significantly decreased (r > 0.50, p < 0.05) and daytime sleepiness showed a significant reduction in 40% of patients. N3 (deep sleep) and REM sleep significantly improved, showing a strong effect (r > 0.50). The apnea-hypopnea index decreased in one of four patients independent of the individual BMI.

CONCLUSIONS

Through polygraphy, we demonstrated impaired sleep patterns in psoriasis and atopic dermatitis patients with itch as a relevant factor and beyond that, rapid sleep improvement under 2 weeks of topical treatment.

Belastung durch gestörten Schlaf und dessen Verbesserung durch topische Behandlung bei Psoriasis und atopischer Dermatitis

INTRODUCTION

Patients with chronic inflammatory skin diseases often suffer from sleep disturbances. However, objective data on sleep architecture, especially to evaluate potential overall influences under therapy, are lacking.

PATIENTS AND METHODS

Pilot study on sleep quality changes including psoriasis and atopic dermatitis patients before and 2 weeks after intensive topical treatment. In addition to disease activity rating, patient-rated outcomes for itch severity and sleep quality and polygraphy was performed before and after topical therapy.

RESULTS

14 psoriasis, eleven atopic dermatitis patients (10 female, 15 male) with a mean age of 49 years were included. Disease activity scores (EASI and PASI) were significantly reduced with topical therapy after 2 weeks (p < 0.001). Pruritus intensity (NRS) showed a significant influence on deep sleep, which resolved after therapy. Insomnia severity significantly decreased (r > 0.50, p < 0.05) and daytime sleepiness showed a significant reduction in 40% of patients. N3 (deep sleep) and REM sleep significantly improved, showing a strong effect (r > 0.50). The apnea-hypopnea index decreased in one of four patients independent of the individual BMI.

CONCLUSIONS

Through polygraphy, we demonstrated impaired sleep patterns in psoriasis and atopic dermatitis patients with itch as a relevant factor and beyond that, rapid sleep improvement under 2 weeks of topical treatment.

Experience and caring needs of patients with psoriasis: A qualitative meta-synthesis

BACKGROUND

As a chronic skin disease, psoriasis often affects the physical, psychological and social status of the patient, which in turn impacts on their experience of illness and needs. However, there is no review of qualitative research that integrates and analyses the experiences and needs of these three influences from a holistic perspective.

METHODS

This review follows the ENTREQ guidelines. Six English databases (JBI, Cochrane Library, PubMed, PsyINFO, CINAHL and Embase) and three Chinese databases (CNKI, VIP and Wanfang) were searched from January 2012 to October 2022. Literature was included if it was relevant to the experience of illness and caring needs of patients with psoriasis. The JBI-QARI was used to rate the quality of included studies.

RESULTS

Eleven studies were included in the meta-synthesis. Four analytical themes were identified for analysis: physical challenges, psychological discomfort, social phenomena and caring needs.

CONCLUSIONS

The combined physical, psychological and social effects of psoriasis and the consequent caring needs should be emphasised. Health professionals, including doctors and nurses, should be aware of the multiple changes in patients and their coping strategies, provide information about psoriasis, monitor and follow-up regularly over time and obtain feedback to inform further treatment and care so as to develop high-quality therapeutic interventions to help and guide patients with their coping strategies.

RELEVANCE TO CLINICAL PRACTICE

These findings describe the physical, psychological and social experiences of illness and caring needs of patients with psoriasis. Healthcare professionals should be more aware of patients' easily overlooked psychological and social distress, providing prompt attention and recognition of patients' experiences and needs, offering relevant assistance and support and enhancing daily, regular follow-up to help them improve their understanding of and ability to manage their illness.

NO PATIENT OR PUBLIC CONTRIBUTION

This is a meta-synthesis without direct patient involvement.

Epidemiological analysis of the patients with psoriasis in Asian countries and region using the same clinical case cards between 2020 and 2022

Although many epidemiological surveys for patients with psoriasis have been reported based on individual countries or facilities, there has been no study encompassing the major countries or the region in Asia. The Asian Society for Psoriasis (ASP) has been conducting an epidemiological study across various Asian countries and regions to elucidate the and compare the epidemiology of psoriasis. A total of 1948 cases were analyzed, with 938 cases from Japan, 530 cases from China, 325 cases from Korea, 141 cases from Chinese Taipei, and 14 cases from Thailand, all of which were enrolled between 2020 and 2022. In the Asian region total, the male-female ratio was 1.87:1 and the peak age at disease onset was 20-29 years. The proportion of psoriasis vulgaris (PsV), psoriatic arthritis (PsA), and pustular psoriasis (PP) was 80.1%, 17.7%, and 2.2%, respectively, and PsA was more commonly associated with nail symptoms than psoriasis vulgaris (PsV). Of the patients, 13% had a familial history of psoriasis and the most frequently affected family member was the father. Regarding treatment, 78.3% of the patients received topical medications, 9.0% underwent phototherapy, 34.0% received oral medications, and 36.1% were treated with biological agents. This study provided valuable information on the epidemiology and treatment of psoriasis using the registry data collected with the common reporting form in the same period in major Asian countries and regions. Male predominance is a distinctive feature of psoriasis in Asia. This epidemiological data registry in the ASP will continue afterwards.

Rapid Improvements in Itch with Tapinarof Cream 1% Once Daily in Two Phase 3 Trials in Adults with Mild to Severe Plaque Psoriasis

INTRODUCTION

Patients with psoriasis report pruritus as their most bothersome symptom. Tapinarof cream 1% once daily demonstrated significant efficacy versus vehicle and was well tolerated in adults with mild to severe plaque psoriasis in two 12-week trials: PSOARING 1 (NCT03956355) and PSOARING 2 (NCT03983980). Here, we present patient-reported pruritus outcomes from these trials.

METHODS

Outcomes included a Peak Pruritus Numerical Rating Scale (PP-NRS) score of 0 or 1 (itch-free state); Dermatology Life Quality Index (DLQI) itch item scores; and Psoriasis Symptom Diary (PSD) itch item scores.

RESULTS

Analyses included 683 tapinarof- and 342 vehicle-treated patients. At baseline, mean pruritus scores were similar across trials with only 7-11% of patients reporting an itch-free state. At week 12, the proportion of tapinarof-treated patients achieving an itch-free state was 50% in both trials compared with 32% (P = 0.0007) and 27% (P < 0.0001) in the vehicle groups. Improvements were apparent at the earliest assessments with continued improvement over the course of the trials. There were rapid and statistically significant improvements in the proportion of patients with a ≥ 4-point improvement in PP-NRS for tapinarof-treated patients versus vehicle from week 2 with 68% vs 46% (P = 0.0004) and 60% vs 31% (P = 0.0001) at week 12 achieving a response in each trial. Significantly greater reductions in itch with tapinarof versus vehicle were also demonstrated at week 12 for DLQI itch item 1 (P = 0.0026 and P < 0.0001), PSD item 1 (both P < 0.0001), and PSD item 2 (both P < 0.0001).

CONCLUSION

Tapinarof was highly efficacious in reducing pruritus across multiple patient-reported outcome measures, with rapid, statistically significant, and clinically meaningful improvements. The high proportion of patients achieving the treatment target of an itch-free state at week 12 (50%) is a noteworthy clinical outcome for a non-steroidal topical cream in the treatment of mild to severe plaque psoriasis.

TRIAL REGISTRATION

Clinical trial registration information: NCT03956355, NCT03983980.

The regulation of the PD-1/PD-L1 pathway in imiquimod-induced chronic psoriasis itch and itch sensitization in mouse

PD-1/PD-L1 inhibitors have been demonstrated to induce itch in both humans and experimental animals. However, whether the PD-1/PD-L1 pathway is involved in the regulation of chronic psoriatic itch remains unclear. This study aimed to investigate the role of the PD-1/PD-L1 pathway in imiquimod-induced chronic psoriatic itch. The intradermal injection of PD-L1 in the nape of neck significantly alleviated chronic psoriatic itch in imiquimod-treated skin. Additionally, we observed that spontaneous scratching behavior induced by imiquimod disappeared on day 21. Still, intradermal injection of PD-1/PD-L1 inhibitors could induce more spontaneous scratching for over a month, indicating that imiquimod-treated skin remained in an itch sensitization state after the spontaneous scratching behavior disappeared. During this period, there was a significant increase in PD-1 receptor expression in both the imiquimod-treated skin and the spinal dorsal horn in mice, accompanied by significant activation of microglia in the spinal dorsal horn. These findings suggest the potential involvement of the peripheral and central PD-1/PD-L1 pathways in regulating chronic itch and itch sensitization induced by imiquimod.

Mechanisms of the PD-1/PD-L1 pathway in itch: From acute itch model establishment to the role in chronic itch in mouse

Programmed cell death receptor/ligand 1 (PD-1/PD-L1) blockade therapy for various cancers induces itch. However, few studies have evaluated the mechanism underlying PD-1/PD-L1 inhibitor-induced itch. This study aimed to establish and evaluate a mouse model of acute itch induced by PD-1/PD-L1 inhibitors and to explore the role of the PD-1/PD-L1 pathway in chronic itch. The intradermal injection of the PD-1/PD-L1 small molecule inhibitors, or anti-PD-1/PD-L1 antibodies in the nape of the neck in the mice elicited intense spontaneous scratches. The model was evaluated using pharmacological methods. The number of scratches was reduced by naloxone but not by antihistamines or the transient receptor potential (TRP) channel inhibitor. Moreover, the PD-1 receptor was detected in the spinal cord of the mouse models of chronic itch that exhibited acetone, diethyl ether, and water (AEW)-induced dry skin, imiquimod-induced psoriasis, and 1-fluoro-2,4-dinitrobenzene (DNFB)-induced allergic contact dermatitis. Intrathecal PD-L1 (1 μg, 4 times a week for 1 week) suppressed the activation of the microglia in the spinal dorsal horn to relieve the chronic itch that was elicited by imiquimod-induced psoriasis and DNFB-induced allergic contact dermatitis. Although the activation of the microglia in the spinal dorsal horn was not detected in the AEW-treated mice, intrathecal PD-L1 still reduced the number of scratches that were elicited by AEW. Our findings suggest that histamine receptor inhibitors or TRP channel inhibitors have limited effects on PD-1/PD-L1 inhibitor-induced itch and that spinal PD-1 is important for the spinal activation of the microglia, which may underlie chronic itch.

Efficacy of Avène Hydrotherapy on Chronic Pruritus in Patients with Plaque Psoriasis

INTRODUCTION

Pruritus is a prevalent symptom, described as one of the most bothersome of psoriasis. Specific itch management remains a challenge, for which hydrotherapy could be used as adjunct care to medical treatment. Therefore, we assessed the immediate and longer-term benefit of 3 weeks of Avène thermal spring water hydrotherapy on chronic pruritus in patients in addition to their usual psoriasis and/or pruritus management.

METHODS

Twenty-six patients suffering from chronic pruritus due to psoriasis were evaluated before and after 3 weeks of hydrotherapy with a 3 and 6 month follow-up. A control group (18 patients) did not undergo hydrotherapy and continued to follow their usual skin management. Pruritus was assessed according to the numeric rating scale (NRS, pruritus intensity), the visual dynamic pruritus score (vDPS, change in pruritus intensity), and the 5-D itch scale (pruritus characteristics). Psoriasis severity was measured using the psoriasis area and severity index (PASI) score. The "itchy quality of life" (ItchQoL) scale was used to assess quality-of-life (QoL) impact related to itch. Pruritus and psoriasis gene and protein biomarkers were measured in lesional and nonlesional skin.

RESULTS

Pruritus measurements (NRS, vDPS, and 5-D itch scale) indicated an immediate and long-lasting positive effect of hydrotherapy compared with control patients. The psoriasis area and severity index (PASI) was decreased by 40.0% by hydrotherapy, which was sustained over 6 months. The ItchQoL also improved directly after hydrotherapy, which was still much improved even 6 months later. Analysis of gene and/or protein biomarkers revealed a significant decrease of inflammation biomarkers (IL-8, IL-1α, IL-1RA, and RANTES), of psoriasis biomarkers (PI3, S100A7, and IL-17), and of pruritus biomarkers (IL-31, TRPV1, and CGRP1).

CONCLUSIONS

These findings demonstrated an immediate and long-lasting improvement of pruritus in patients with psoriasis who underwent Avène thermal spring water hydrotherapy, indicating that this would be a good complementary therapy in the management of this disease.

TRIAL REGISTRATION

NCT03023254.

Automated Machine Learning Analysis of Patients With Chronic Skin Disease Using a Medical Smartphone App: Retrospective Study

BACKGROUND

Rapid digitalization in health care has led to the adoption of digital technologies; however, limited trust in internet-based health decisions and the need for technical personnel hinder the use of smartphones and machine learning applications. To address this, automated machine learning (AutoML) is a promising tool that can empower health care professionals to enhance the effectiveness of mobile health apps.

OBJECTIVE

We used AutoML to analyze data from clinical studies involving patients with chronic hand and/or foot eczema or psoriasis vulgaris who used a smartphone monitoring app. The analysis focused on itching, pain, Dermatology Life Quality Index (DLQI) development, and app use.

METHODS

After extensive data set preparation, which consisted of combining 3 primary data sets by extracting common features and by computing new features, a new pseudonymized secondary data set with a total of 368 patients was created. Next, multiple machine learning classification models were built during AutoML processing, with the most accurate models ultimately selected for further data set analysis.

RESULTS

Itching development for 6 months was accurately modeled using the light gradient boosted trees classifier model (log loss: 0.9302 for validation, 1.0193 for cross-validation, and 0.9167 for holdout). Pain development for 6 months was assessed using the random forest classifier model (log loss: 1.1799 for validation, 1.1561 for cross-validation, and 1.0976 for holdout). Then, the random forest classifier model (log loss: 1.3670 for validation, 1.4354 for cross-validation, and 1.3974 for holdout) was used again to estimate the DLQI development for 6 months. Finally, app use was analyzed using an elastic net blender model (area under the curve: 0.6567 for validation, 0.6207 for cross-validation, and 0.7232 for holdout). Influential feature correlations were identified, including BMI, age, disease activity, DLQI, and Hospital Anxiety and Depression Scale-Anxiety scores at follow-up. App use increased with BMI >35, was less common in patients aged >47 years and those aged 23 to 31 years, and was more common in those with higher disease activity. A Hospital Anxiety and Depression Scale-Anxiety score >8 had a slightly positive effect on app use.

CONCLUSIONS

This study provides valuable insights into the relationship between data characteristics and targeted outcomes in patients with chronic eczema or psoriasis, highlighting the potential of smartphone and AutoML techniques in improving chronic disease management and patient care.

S. aureus drives itch and scratch-induced skin damage through a V8 protease-PAR1 axis

Itch is an unpleasant sensation that evokes a desire to scratch. The skin barrier is constantly exposed to microbes and their products. However, the role of microbes in itch generation is unknown. Here, we show that Staphylococcus aureus, a bacterial pathogen associated with itchy skin diseases, directly activates pruriceptor sensory neurons to drive itch. Epicutaneous S. aureus exposure causes robust itch and scratch-induced damage. By testing multiple isogenic bacterial mutants for virulence factors, we identify the S. aureus serine protease V8 as a critical mediator in evoking spontaneous itch and alloknesis. V8 cleaves proteinase-activated receptor 1 (PAR1) on mouse and human sensory neurons. Targeting PAR1 through genetic deficiency, small interfering RNA (siRNA) knockdown, or pharmacological blockade decreases itch and skin damage caused by V8 and S. aureus exposure. Thus, we identify a mechanism of action for a pruritogenic bacterial factor and demonstrate the potential of inhibiting V8-PAR1 signaling to treat itch.

Tildrakizumab improves high burden skin symptoms, impaired sleep and quality of life of moderate-to-severe plaque psoriasis patients in conditions close to clinical practice

BACKGROUND

Tildrakizumab (TIL) is an interleukin (IL)-23p19 inhibitor for the treatment of moderate-to-severe plaque psoriasis with long-term efficacy and safety demonstrated in Phase III trials. Studies conducted in conditions closer to clinical practice are needed.

OBJECTIVES

The TRIBUTE study (open-label, Phase IV) assessed the efficacy and impact on health-related quality of life (HRQoL) of TIL 100 mg in adult moderate-to-severe psoriasis patients (naïve to IL-23/Th17 pathway inhibitors) in conditions similar to clinical practice.

METHODS

Key efficacy measure was Psoriasis Area Severity Index (PASI). HRQoL was evaluated using the Dermatology Life Quality Index (DLQI) and Skindex-16. Additional patient-reported outcomes included Pain-, Pruritus- and Scaling-Numerical Rating Scale (NRS), Medical Outcome Study (MOS)-Sleep, Work Productivity and Activity Impairment (WPAI), Patient Benefit Index (PBI) and Treatment Satisfaction Questionnaire for Medication (TSQM).

RESULTS

One hundred and seventy-seven patients were enrolled (six patients did not complete the study). After 24 weeks, the proportion of patients achieving PASI scores ≤ 3, PASI 75, PASI 90 and DLQI 0/1 was 88.4%, 92.5%, 74.0% and 70.4%, respectively. Skindex-16 overall score improved (mean absolute change from baseline, MACB [95%CI]: -53.3 [-58.1, -48.5]). Significant benefits (MACB [95%CI]) were found on pruritus-, pain- and scaling-NRS scores (-5.7 [-6.1, -5.2], -3.5 [-4.1, -3.0] and -5.7 [-6.2, -5.2], respectively), MOS-Sleep (-10.4 [-13.3, -7.4] Sleep problems Index II) and WPAI (-36.4 [-42.6, -30.2] activity impairment, -28.2 [-34.7, -21.7] productivity loss, -27.0 [-32.9, -21.1] presenteeism and -6.8 [-12.1, -1.5] absenteeism). 82.7% of patients reported PBI ≥ 3 and the mean (SD) global TSQM score was high (80.5 [18.5]). Only one serious treatment-emergent adverse event was reported (not-related to TIL).

CONCLUSIONS

TIL 100 mg treatment after 24 weeks in conditions close to real clinical practice showed a quick and high improvement in psoriasis signs and HRQoL. Patient reported improvements in sleep outcomes and work productivity, relevant benefits and high treatment satisfaction. The safety profile was favourable and consistent with Phase III trials.

Pathomechanism of Pruritus in Psoriasis and Atopic Dermatitis: Novel Approaches, Similarities and Differences

Pruritus is defined as an unpleasant sensation that elicits a desire to scratch. Nearly a third of the world's population may suffer from pruritus during their lifetime. This symptom is widely observed in numerous inflammatory skin diseases-e.g., approximately 70-90% of patients with psoriasis and almost every patient with atopic dermatitis suffer from pruritus. Although the pathogenesis of atopic dermatitis and psoriasis is different, the complex intricacies between several biochemical mediators, enzymes, and pathways seem to play a crucial role in both conditions. Despite the high prevalence of pruritus in the general population, the pathogenesis of this symptom in various conditions remains elusive. This review aims to summarize current knowledge about the pathogenesis of pruritus in psoriasis and atopic dermatitis. Each molecule involved in the pruritic pathway would merit a separate chapter or even an entire book, however, in the current review we have concentrated on some reports which we found crucial in the understanding of pruritus. However, the pathomechanism of pruritus is an extremely complex and intricate process. Moreover, many of these signaling pathways are currently undergoing detailed analysis or are still unexplained. As a result, it is currently difficult to take an objective view of how far we have come in elucidating the pathogenesis of pruritus in the described diseases. Nevertheless, considerable progress has been made in recent years.

Regulatory Mechanism of the IL-33-IL-37 Axis via Aryl Hydrocarbon Receptor in Atopic Dermatitis and Psoriasis

Interleukin (IL)-33 and IL-37 have been identified as novel cytokines involved in various inflammatory diseases. However, their specific roles remain largely unknown. Recent studies have shown that IL-33, which triggers inflammation, and IL-37, which suppresses it, cooperatively regulate the balance between inflammation and anti-inflammation. IL-33 and IL-37 are also deeply involved in the pathogenesis of inflammatory skin diseases such as atopic dermatitis (AD) and psoriasis. Furthermore, a signaling pathway by which aryl hydrocarbon receptor (AHR), a receptor for dioxins, regulates the expression of IL-33 and IL-37 has been revealed. Here, we outline recent findings on the mechanisms regulating IL-33 and IL-37 expression in AD and psoriasis. IL-33 expression is partially dependent on mitogen-activated protein kinase (MAPK) activation, and IL-37 has a role in suppressing MAPK in human keratinocytes. Furthermore, IL-33 downregulates skin barrier function proteins including filaggrin and loricrin, thereby downregulating the expression of IL-37, which colocalizes with these proteins. This leads to an imbalance of the IL-33-IL-37 axis, involving increased IL-33 and decreased IL-37, which may be associated with the pathogenesis of AD and psoriasis. Therefore, AHR-mediated regulation of the IL-33-IL-37 axis may lead to new therapeutic strategies for the treatment of AD and psoriasis.

Once-daily roflumilast foam 0.3% for scalp and body psoriasis: a randomized, double-blind, vehicle-controlled phase IIb study

BACKGROUND

Scalp psoriasis affects most patients with psoriasis, but it can be difficult to treat.

OBJECTIVES

To evaluate the efficacy and safety of once-daily roflumilast foam 0.3% on scalp and body psoriasis.

METHODS

In a phase IIb randomized controlled trial, adults and adolescents aged ≥ 12 years with scalp and body psoriasis were randomized (2 : 1) to roflumilast foam 0.3% or vehicle for 8 weeks. The primary efficacy endpoint was scalp Investigator Global Assessment (S-IGA) success (score of 'clear' or 'almost clear' plus ≥ 2-grade improvement from baseline) at week 8. Safety and tolerability were also evaluated.

RESULTS

Significantly more roflumilast-treated patients (59.1%) than vehicle-treated patients (11.4%) achieved S-IGA success at week 8 (P < 0.001); differences favoured roflumilast as early as the first postbaseline visit at week 2 (P < 0.001). Significant improvements were also seen for secondary endpoints, including body IGA success, Scalp Itch Numeric Rating Scale and the Psoriasis Scalp Severity Index. The safety of roflumilast was generally similar to vehicle. Patients treated with roflumilast experienced low rates of treatment-emergent adverse events (AEs), with few discontinuations due to an AE. Few patients with skin of colour (11%) and few adolescents (0.7%) were included.

CONCLUSIONS

The results support the further development of roflumilast foam for treating scalp and body psoriasis.

Topical roflumilast for the treatment of psoriasis

INTRODUCTION

New non-steroidal topical agents are needed for the treatment of psoriasis. Roflumilast cream 0.3% is a once daily phosphodiesterase-4 inhibitor that was recently approved by the FDA for the treatment of plaque psoriasis in adolescents and adults. It is indicated for use on all body surfaces including intertriginous areas.

AREAS COVERED

In this review, we summarize the current knowledge about roflumilast cream for the treatment of psoriasis, highlighting its efficacy and safety profile from published clinical trials. Roflumilast's mechanism of action and pharmacokinetic profile are also discussed.

EXPERT OPINION

Positive results were reported across trials with 48% of patients treated with roflumilast achieving an Investigator Global Assessment score of clear or almost clear at 8 weeks in phase III studies. Most adverse events were mild or moderate in severity and few application-site reactions were reported among participants. Unique advantages of the cream are its success in treating intertriginous areas and its ability to reduce symptoms of itch, results of which may significantly improve quality of life for patients. In the future, real-world data and active comparator trials with existing non-steroidal agents are needed to better understand roflumilast's place in the current treatment landscape.

Nerve growth factor mediates activation of transient receptor potential vanilloid 1 in neurogenic pruritus of psoriasis

Pruritus is a common and painful symptom in psoriasis with profoundly negative impacts on quality of life. The underlying mechanisms of pruritus are complex and multifactorial, and accumulating evidence suggests that pruritus induced by neurogenic inflammation predominates in psoriasis. Nerve growth factor (NGF) -mediated transient receptor potential vanilloid receptor 1(TRPV1) pathway has emerged as a crucial node in the regulation of neurogenic pruritus. TRPV1 appears coupled to most pruritus-specific molecules via the neuro-immune axis. While the modes of regulation differ for each axis, TRPV1 is involved in substantial biochemical crosstalk-causing feedback loops with significant effects on neurogenic pruritus. Therefore, TRPV1 has emerged as a target molecular in drug development for pruritus in psoriasis. However, no significant clinical progress occurred in the development of systemic TRPV1 antagonists due to elevated core temperature. Thus, topical application of TRPV1 antagonists and interference with mediators linked to the TRPV1 activation pathway may be promising therapeutic options to ameliorate pruritus. This Review focuses on recent advances in complicated regulation of NGF-mediated TRPV1 pathway in psoriatic neurogenic pruritus, as well as the therapeutic options that arise from the dissection of the pathway.

Role of Type I Cannabinoid Receptor in Sensory Neurons in Psoriasiform Skin Inflammation and Pruritus

Type I cannabinoid receptor (CB1R) has been reported to exhibit favorable anti-inflammation and antipruritus effects against inflammation-based skin diseases, but the specific mechanism remains to be explored. In this study, we found that the activation of CB1R significantly relieved the scratching behavior and skin inflammation in a psoriatic mouse model, whereas CB1R antagonist aggravated these symptoms. Because the expression of CB1R was abundant in dorsal root ganglia, we constructed mice with conditional CB1R knockout in primary sensory neurons and found that imiquimod-induced psoriasiform inflammation and itch were both worsened in CB1R-conditional knockout mice. Next, we observed that the CB1R was mostly located in peptidergic neurons, and deletion of CB1R in primary sensory neurons promoted the production and release of substance P to the skin tissue. Furthermore, the elevated substance P in the skin affected the activation of extracellular signal‒regulated kinase in keratinocytes and induced the accumulation of mast cells in the dermis. Finally, we showed that blocking the substance P signal significantly alleviated the exacerbation of psoriasiform inflammation and itch caused by imiquimod in CB1R-conditional knockout mice. Together, our work reveals that CB1R in sensory neurons plays a key role in psoriasiform skin inflammation and pruritus by regulating substance P expression.

Experiences and coping behaviours of patients with psoriasis: a qualitative study

BACKGROUND

Psoriasis is a complex, chronic, lifelong inflammatory skin disease characterized by the development of erythematous, indurated, scaly, pruritic and often painful skin plaques, and it is currently incurable. It profoundly affects psychological wellbeing and social functioning and has significant associated co-morbidities. To improve clinical approaches, understanding of the experiences of patients with psoriasis is needed.

OBJECTIVE

To explore the experiences and coping behaviours of patients with psoriasis.

METHODS

A qualitative study approach was conducted. Through semi-structured interviews, 20 patients with psoriasis were recruited from general practices and specialist dermatology practices in a regional teaching hospital in Taiwan. Recorded interviews were transcribed and analysed by content analysis.

RESULTS

Three themes and nine subthemes were identified: 1. Symptoms distress: (a) trouble with scaling, (b) bothersome itching, and (c) complex pain experiences; 2. Psychological distress: (a) encountering discrimination and (b) feeling stigmatised; 3. Managing psoriasis: (a) coping with symptoms, (b) seeking alternative methods, (c) using biologic agents, and (d) changing thinking and coexisting with the disease.

CONCLUSION

The experience of patients with psoriasis has significant negative impacts on their lives. The findings of this study can provide healthcare professionals with a reference for the care of patients with psoriasis.

Effect of Roflumilast Cream (ARQ-151) on Itch and Itch-Related Sleep Loss in Adults with Chronic Plaque Psoriasis: Patient-Reported Itch Outcomes of a Phase 2b Trial

BACKGROUND

Itch is the most bothersome symptom reported by patients with psoriasis. Safe and effective treatments for psoriasis that also address itch are needed.

OBJECTIVES

To report effects of roflumilast cream on itch-related outcomes from a Phase 2b trial.

METHODS

Adults with chronic plaque psoriasis were randomized to roflumilast 0.3%, roflumilast 0.15%, or vehicle once-daily for 12 weeks. Psoriasis severity was assessed via the Investigator Global Assessment (IGA; a 5-point scale assessing plaque thickening, scaling, and erythema ranging from 0 [clear] to 4 [severe]) and ≥ 2 on a modified Psoriasis Area and Severity Index (PASI-HD, which combines severity of lesions and area affected, ranging from 0 [no disease] to 72 [maximal disease], with the actual percentage of the anatomical area involved in those patients with < 10% of anatomical area involved [e.g., 0.1 for 1% to 0.9 for 9%]). Itch was evaluated via Worst Itch Numeric Rating Scale (WI-NRS), Psoriasis Symptom Diary (PSD) Items 1 (severity of itch) and 2 (bother of itch), and itch-related sleep loss NRS scores. Post hoc correlation analyses between WI-NRS and PASI, WI-NRS and itch-related sleep loss, and WI-NRS and DLQI were also performed.

RESULTS

Roflumilast-treated patients had significantly greater improvements than vehicle-treated patients in WI-NRS and PSD Items 1 and 2 beginning at Week 2 and in itch-related sleep loss Weeks 6 through 12. Among patients with baseline WI-NRS ≥ 6, significantly more patients achieved ≥ 4-point improvement with roflumilast than with vehicle as early as Week 2. Itch severity had low correlation with PASI while WI-NRS and IGA were not always aligned.

LIMITATIONS

The first assessment was at 2 weeks, limiting the ability to assess early onset of itch response.

CONCLUSION

Roflumilast cream improved itch and itch-related sleep loss associated with chronic plaque psoriasis.

CLINICALTRIALS

GOV IDENTIFIER

NCT03638258.

Effectiveness of brodalumab in improving itching and skin pain in Japanese patients with psoriasis: The ProLOGUE study

Itching and skin pain are bothersome symptoms of psoriasis, but evidence is limited regarding the treatment effectiveness on these symptoms in daily clinical settings. We assessed the changes in the levels of itching and skin pain after brodalumab treatment in Japanese patients with psoriasis using patient-reported outcomes (PROs). Patients with psoriasis who have inadequate response to existing treatments were enrolled in the single-arm, open-label, multicenter, prospective ProLOGUE study and received brodalumab 210 mg subcutaneously in daily clinical practice. Psoriasis Area and Severity Index (PASI) and PRO assessments were performed at baseline and weeks 12 and 48. Seventy-three patients (men, 82.2%; median age, 54.0 years) were enrolled. The Itch Numeric Rating Scale (NRS; p < 0.0001 at weeks 12 and 48) and Skin Pain NRS (week 12, p = 0.0004; week 48, p < 0.0001) scores significantly decreased from baseline. The Itch NRS score was significantly higher in patients with a Dermatology Life Quality Index (DLQI) score of ≥2 (vs. 0/1; p < 0.0001 at weeks 12 and 48) and in patients with a Treatment Satisfaction Questionnaire for Medication-9 (TSQM-9) global satisfaction domain score of ≤70% (vs. >70%; week 12, p = 0.0120; week 48, p = 0.0348). The Itch NRS score cutoff value for achieving a PASI score of ≤2, DLQI score of 0/1, and TSQM-9 global satisfaction domain score of >70% was 1 at week 12 and 0 at week 48. Brodalumab treatment was associated with improvement in itching and skin pain in Japanese patients with psoriasis. An Itch NRS score of 0 can be a long-term treatment goal for psoriasis (Japan Registry of Clinical Trials identifier: jRCTs031180037).

Effectiveness and safety of auricular acupuncture for psoriasis: A protocol for systematic review and meta-analysis

BACKGROUND

Psoriasis is a chronic, immune-mediated, polygenic skin disease that is common in clinical practice and often develops on the extremities, back, and scalp of patients. In that psoriasis lesions are stubborn and prone to recurrence, it has a serious impact on patients' quality of life and is detrimental to their physical and psychological health. Auricular acupuncture is one of the traditional Chinese medical treatments, which has the advantages of low adverse effects and simple operation and has been widely used in clinical practice with good efficacy. However, there has been no systematic evaluation of auricular acupuncture in the treatment of psoriasis. This protocol aims to evaluate the effectiveness and safety of auricular acupuncture in patients with psoriasis.

METHODS

We will search the following 8 databases including PubMed, MEDLINE, EMBASE, Cochrane Library, CNKI, Wan Fang, VIP, and CBM databases for randomized controlled trials of auricular acupuncture treated psoriasis from their inception to 10 October 2022. We will analyze the data meeting the inclusion criteria with the RevMan V.5.4 software. Two authors will assess the quality of the study with the Cochrane systematic evaluation tool. Treatment effectiveness and the psoriasis area and severity index are defined as the main outcomes, and the additional outcomes include itchy, dermatology life quality index, relapse rate, and adverse events.

RESULTS

This study will review and evaluate the available evidence on the effectiveness and safety of auricular acupuncture for psoriasis.

CONCLUSIONS

The results of this study will provide evidence for the effectiveness and safety of treating psoriasis, providing clinicians and patients with appropriate treatment options for this disease.

In vitro models for investigating itch

Itch (pruritus) is a sensation that drives a desire to scratch, a behavior observed in many animals. Although generally short-lasting and not causing harm, there are several pathological conditions where chronic itch is a hallmark symptom and in which prolonged scratching can induce damage. Finding medications to counteract the sensation of chronic itch has proven difficult due to the molecular complexity that involves a multitude of triggers, receptors and signaling pathways between skin, immune and nerve cells. While much has been learned about pruritus from in vivo animal models, they have limitations that corroborate the necessity for a transition to more human disease-like models. Also, reducing animal use should be encouraged in research. However, conducting human in vivo experiments can also be ethically challenging. Thus, there is a clear need for surrogate models to be used in pre-clinical investigation of the mechanisms of itch. Most in vitro models used for itch research focus on the use of known pruritogens. For this, sensory neurons and different types of skin and/or immune cells are stimulated in 2D or 3D co-culture, and factors such as neurotransmitter or cytokine release can be measured. There are however limitations of such simplistic in vitro models. For example, not all naturally occurring cell types are present and there is also no connection to the itch-sensing organ, the central nervous system (CNS). Nevertheless, in vitro models offer a chance to investigate otherwise inaccessible specific cell–cell interactions and molecular pathways. In recent years, stem cell-based approaches and human primary cells have emerged as viable alternatives to standard cell lines or animal tissue. As in vitro models have increased in their complexity, further opportunities for more elaborated means of investigating itch have been developed. In this review, we introduce the latest concepts of itch and discuss the advantages and limitations of current in vitro models, which provide valuable contributions to pruritus research and might help to meet the unmet clinical need for more refined anti-pruritic substances.

Elevation of IgE in patients with psoriasis: Is it a paradoxical phenomenon?

Immunoglobulin E (IgE) elevation is a hallmark of allergic conditions such as atopic dermatitis (AD). The pathogenesis of AD is typically associated with high levels of IL-4 and IL-13 produced by activated T helper 2 (Th2) cells. Psoriasis, on the other hand, is an inflammatory skin disease mainly driven by Th17 cells and their related cytokines. Although the immunopathologic reactions and clinical manifestations are often easily distinguished in the two skin conditions, patients with psoriasis may sometimes exhibit AD-like manifestations, such as elevated IgE and persistent pruritic lesions. Given the fact that the effective T cells have great plasticity to re-differentiate in response to innate and environmental factors, this unusual skin condition could be a consequence of a cross-reaction between distinct arms of T-cell and humoral immunity. Here we review the literature concerning the roles of IgE in the development of AD and psoriasis, showing that elevated IgE seems to be an important indicator for this non-typical psoriasis.

Itch as a critical factor in impaired health-related quality of life in patients with plaque psoriasis achieving clear or almost-clear skin: Analysis of the single-arm, open-label, multicenter, prospective ProLOGUE study

Background

Patients with psoriasis report impaired health-related quality of life (HRQoL; Dermatology Life Quality Index score ≥ 2) even after achieving clear or almost-clear skin with biologic treatment.

Objective

To assess the effectiveness of brodalumab in HRQoL improvement and the factors associated with incomplete HRQoL improvement in Japanese patients with psoriasis.

Methods

As a part of the single-arm, open-label, multicenter, prospective ProLOGUE study (Japan Registry of Clinical Trials identifier: jRCTs031180037), patients were treated with 210 mg of subcutaneous brodalumab in daily clinical practice until week 48. The absolute Psoriasis Area and Severity Index scores and patient-reported outcomes were assessed at baseline and weeks 12 and 48.

Results

Seventy-three patients (male, 82.2%; median age, 54.0 years) were enrolled. The Dermatology Life Quality Index and European Quality of Life 5-Dimension 5-Level Utility Index scores significantly improved from baseline to weeks 12 and 48. At week 48, all 13 patients with a Dermatology Life Quality Index score of ≥2 and an absolute Psoriasis Area and Severity Index score of 0 to ≤2 reported itching.

Limitations

Unclear generalizability of the results to other biologics.

Conclusion

Treatment with brodalumab improved HRQoL in patients with psoriasis. Itching may contribute to incomplete HRQoL improvement in patients who have achieved clear or almost-clear skin.

A comprehensive, tri-national, cross-sectional analysis of characteristics and impact of pruritus in psoriasis

BACKGROUND

Pruritus is prevalent in psoriasis but still many features of pruritus, its response to therapy and its burden in psoriasis remain to be better characterized.

OBJECTIVE

To investigate characteristics and burden of pruritus in an international cohort of patients with psoriasis.

METHODS

This cross-sectional study included a total of 634 patients and 246 controls from Germany, Poland and Russia. Physicians examined and interviewed participants, recording clinical characteristics, such as severity, therapy and localization of psoriatic lesions. Participants filled out self-reported questionnaires including questions on pruritus severity and impact, characteristics, and response to therapy, and quality of life (QoL). Localization patterns of pruritus and skin lesions were visualized using body heat maps.

RESULTS

Most patients (82%) experienced pruritus throughout their disease, and 75% had current pruritus. The majority of patients (64%) perceived pure pruritus, and those who reported additional painful and/or burning sensations (36%) reported overall stronger pruritus. The scalp was the most frequently reported localization of pruritus, even in the absence of skin lesions. Body surface area (BSA) of pruritus was not linked to pruritus intensity, but to BSA of psoriatic lesions (rho = 0.278; P < 0.001). One third of patients (31%) reported impaired sex-life, and 4% had suicidal ideations due to pruritus. In up to one third of patients, psoriasis therapies had little or no effect on pruritus. The only therapeutic option offered to some of these patients were antihistamines, which appeared to be effective in most cases.

CONCLUSION

Pruritus is highly prevalent in psoriasis and is linked to a significant burden. Current psoriasis therapies are frequently insufficient to control pruritus. Managing psoriasis should include the assessment and control of itch. Efficient antipruritic therapies should be developed and be made available for patients with psoriasis.

Zugang und Inanspruchnahme psychosomatischer Versorgung aus ärztlicher Sicht: Eine qualitative Interviewstudie

Hintergrund Chronisch entzündliche Hauterkrankungen sind häufig mit psychosozialen Beeinträchtigungen und einer reduzierten Lebensqualität vergesellschaftet. Ziel dieser Studie war es zu erfassen, wie spezialisiertes medizinisches Personal eines universitären Haut-Entzündungszentrums die Zugangswege und die Inanspruchnahme psychosomatischer Sondierungsgespräche oder Kurzzeitinterventionen bei PatientInnen mit chronisch entzündlichen Hauterkrankungen wahrnimmt.

Methoden Es wurden qualitative Erhebungen in Form von 10 Einzelinterviews mit medizinischem Personal durchgeführt, das zum Zeitpunkt der Befragung im Zentrum für entzündliche Hauterkrankungen der Uni-Hautklinik tätig war. Die Daten wurden inhaltsanalytisch mithilfe einer qualitativen Analysesoftware ausgewertet.

Ergebnisse Die Ergebnisse aus den geführten Einzelinterviews ergaben, dass die Einbindung einer psychosomatischen Versorgung innerhalb eines dermatologischen Entzündungszentrums vom ärztlichen Personal als durchweg positiv bewertet wurde. Die Option auf ein zeit- und zentrumsnahes Gesprächsangebot nimmt dabei eine besondere Rolle ein. Experten fühlen sich mit der ortsnahen Einbindung psychosomatischer Expertise sicherer im Umgang mit belasteten Patient*innen. Der holistische Ansatz scheint einen positiven Einfluss auf die individuelle Behandlung und die Beziehungsgestaltung mit den Patient*innen zu nehmen. Dabei zeigten sich keine wesentlichen Unterschiede im Geschlecht und über verschiedene Altersgruppen hinweg.

Diskussion Die Möglichkeit zur zentrumsnahen Anbindung von belasteten Patient*innen in Form von zusätzlichen psychosomatischen Sondierungsgesprächen wie auch dem Einsatz von adaptierten Kurzzeitinterventionen trägt zur holistischen Behandlung bei, scheint einen günstigen Einfluss auf den somatischen Behandlungsverlauf zu nehmen und unterstützt Ärzt*innen in ihrer Behandlung.

Chronic Plaque Psoriasis in Poland: Disease Severity, Prevalence of Comorbidities, and Quality of Life

The epidemiology of psoriasis has not been widely assessed in Polish population so far. This study aimed to investigate psoriasis epidemiological situation by evaluating disease course and severity, management, comorbidities, environmental factors, and knowledge about this disorder among psoriatic patients in Poland. A cross-sectional cohort population-based study enrolled 1080 psoriatic patients and 1200 controls. The mean age of psoriasis onset was 27.6 years; 78.24% had type I psoriasis. Positive family history of psoriasis was reported in 44.81% of patients, whereas itch was reported in vast majority of patients (83.33%). Based on PASI score moderate psoriasis was the most common in studied group (mean 12.63 ± 9.33, range 0−67.2). The DLQI score (12.01 ± 7.41, range 0−30.0) indicated a very large effect of psoriasis on the quality of life. Hypertension was the most prevalent comorbidity (33.80%), followed by obesity (16.85%) and dyslipidemia (11.85%). Stress was the foremost cause of disease exacerbation (66.20%); however, infections (44.07%) and seasonal changes (45.09%) had also an impact on the course of psoriasis. Psoriatic patients were more often smokers (37.59%) vs. general population (27.50%; p < 0.0001). In conclusion, epidemiological studies help clinicians in better disease and patient understanding, which may translate into better management and patient compliance.

Topical Treatment of Colquhounia Root Relieves Skin Inflammation and Itch in Imiquimod-Induced Psoriasiform Dermatitis in Mice

Itch is one of the major clinical manifestations of psoriasis, which is closely related with neurogenic inflammation and difficult to control. Colquhounia Root (CR) is a Chinese herb exhibiting broad bioactivities on anti-inflammation. This study was designed to explore the antipsoriatic and anti-itch potential of CR and its underlying mechanisms. Mice in a model of imiquimod-induced psoriasiform dermatitis were treated topically with CR for 7 days, and the severity of skin lesions and itch was significantly ameliorated. CR reduced the inflammatory cell infiltration, as well as mast cells in skins. Particularly, the expression of inflammatory cytokines and chemokine including Il17a, Il22, and Ccl20 and itch-related molecules such as SP, CGRP, and NGF in lesions were decreased in diseased mice upon application with CR. The normal human epidermal keratinocytes were stimulated with the M5 cytokine cocktail, the mixture of IL-17A, IL-22, Oncostatin M, IL-1α, and TNF-α, and cell viability and mRNA expression levels of inflammatory factors and itch-related molecules were measured after being treated with CR. We found that CR inhibited both cell hyperproliferation and overexpression of inflammatory cytokines and itch-related molecules in vitro. Altogether, we conclude that CR relieves psoriatic lesions and itch via controlling immunological and neurogenic inflammation.

Nociceptive Sensory Fibers Drive Interleukin-23 Production in a Murine Model of Psoriasis via Calcitonin Gene-Related Peptide

Neuroimmunity is involved in the pathogenesis of psoriasis, but the mechanism underlying the interaction between the nervous system and the interleukin (IL)-23/IL-17 immune axis is yet unclear. This study reveals the essential role of the sensory neuron-derived calcitonin gene-related peptide (CGRP) in imiquimod (IMQ)-induced expression of IL-23. First, we show that the increased nociceptive behavior was consistent with the development of psoriasiform dermatitis, which requires intact sensory innervation. Systemic ultrapotent Transient receptor potential vanilloid 1 (TRPV1) agonist (resiniferatoxin, RTX) treatment-induced sensory denervation resulted in a significant decrease in IL-23 expression in this model, while the recombinant IL-23 treatment induced IL-17A expression was intact after RTX treatment. In addition, IMQ exposure induced a transient increase in CGRP expression in the dorsal root ganglion. The neuron-derived CGRP expression was completely abolished by sensory denervation, thereby downregulating IL-23 expression, which could be reversed through the introduction of CGRP into the denervated dorsal skin. Our results suggest that nociceptive sensory neurons may drive the production of IL-23, resulting in IL-17A production from γδ T cells via the neuropeptide CGRP in the pathology of psoriasis.

The 5-HT1A receptor agonist, 8-OH-DPAT, attenuates long-lasting pain in imiquimod-induced psoriasis in mice

Psoriasis pain is a common symptom underestimated and rarely evaluated in psoriasis clinical trials. This work aimed to investigate whether the development of secondary chronic allodynia and hyperalgesia in the imiquimod (IMQ)-induced psoriasis mice model could be modulated by anti-inflammatory agents and compound 48/80 (C48/80) and to determine whether the activation of 5-HT_1A receptor modulates these nociceptive behaviours. C57BL/6 male mice were treated with 5% IMQ for 7 days. The paw withdrawal responses to von Frey filaments (10 and 250 mN) were used to assess the allodynia and hyperalgesia. Nociceptive behaviours were also evaluated using ketorolac 15 mg/kg s.c., adalimumab 10 mg/kg s.c. and C48/80 10 mg/kg i.p. Then, the serum serotonin and the impact of 8-OH-DPAT (1 mg/kg s.c), a 5-HT_1A receptor agonist, on long-lasting pain were examined. Mice receiving IMQ showed enhanced nociception, which decreased with all tested compounds. The serum serotonin in the IMQ group showed a significant decrease (947.042 ng/ml) regarding the control group (1143.68 ng/ml). The pretreatment with 8-OH-DPAT alleviated pain-related behaviours. These results suggest that the long-lasting pain resulting from psoriasis inflammation is also associated with the serotonergic system. The 5-HT1A receptor should be further explored as a potential therapeutic target for psoriasis pain modulation.

Skin Barrier Dysregulation in Psoriasis

The skin barrier is broadly composed of two elements-a physical barrier mostly localised in the epidermis, and an immune barrier localised in both the dermis and epidermis. These two systems interact cooperatively to maintain skin homeostasis and overall human health. However, if dysregulated, several skin diseases may arise. Psoriasis is one of the most prevalent skin diseases associated with disrupted barrier function. It is characterised by the formation of psoriatic lesions, the aberrant differentiation and proliferation of keratinocytes, and excessive inflammation. In this review, we summarize recent discoveries in disease pathogenesis, including the contribution of keratinocytes, immune cells, genetic and environmental factors, and how they advance current and future treatments.

Lipid-based nanoparticles for psoriasis treatment: a review on conventional treatments, recent works, and future prospects

Psoriasis is a lingering inflammatory skin disease that attacks the immune system. The abnormal interactions between T cells, immune cells, and inflammatory cytokines causing the epidermal thickening. International guidelines have recommended topical treatments for mild to moderate psoriasis whilst systemic and phototherapy treatments for moderate to severe psoriasis. However, current therapeutic approaches have a wider extent to treat moderate to severe type of psoriasis especially since the emergence of diverse biologic agents. In the meantime, topical delivery of conventional treatments has prompted many unsatisfactory effects to penetrate through the skin (stratum corneum). By understanding the physiology of stratum corneum barrier functions, scientists have developed different types of lipid-based nanoparticles like solid lipid nanoparticles, nanostructured lipid carriers, nanovesicles, and nanoemulsions. These novel drug delivery systems help the poorly solubilised active pharmaceutical ingredient reaches the targeted site seamlessly because of the bioavailability feature of the nanosized molecules. Lipid-based nanoparticles for psoriasis treatments create a paradigm for topical drug delivery due to their lipids' amphiphilic feature to efficiently encapsulate both lipophilic and hydrophilic drugs. This review highlights different types of lipid-based nanoparticles and their recent works of nano formulated psoriasis treatments. The encapsulation of psoriasis drugs through lipid nanocarriers unfold numerous research opportunities in pharmaceutical applications but also draw challenges for the future development of nano drugs.

Characteristics of Pruritus in Various Clinical Variants of Psoriasis: Results of the Multinational, Multicenter, Cross-Sectional Study

Psoriasis is a chronic, inflammatory skin disease present in about 3% of the world’s population. The clinical symptoms manifest diversely, therefore one can distinguish several subtypes of psoriasis. The majority of patients with psoriasis experience pruritus, which is an unpleasant sensation that decreases patients’ quality of life. The knowledge on pruritus in different subtypes of psoriasis is limited. We have performed a cross-sectional, prospective, and multicenter study to evaluate the relationship between clinical subtypes of psoriasis (large-plaque, nummular, guttate, palmoplantar, inverse, erythrodermic, palmoplantar pustular, generalized pustular psoriasis, and psoriasis of the scalp) and the prevalence, intensity, and clinical manifestation of itch. We introduced a questionnaire assessing various aspects of pruritus to a total of 254 patients. Out of these, 42 were excluded. Pruritus was present in 92.9% of the remaining patients and its prevalence did not depend on the clinical subtype. A correlation between the severity of psoriasis and the intensity of itch was explicitly noticeable in palmoplantar pustular psoriasis and scalp psoriasis (p < 0.05). The itch sensation was individual and differed among subtypes of psoriasis. In conclusion, pruritus is a frequent phenomenon, and its presentation is different in various subtypes of psoriasis.

Prevalence and Characteristics of Psoriasis in Romania-First Study in Overall Population

Background: Psoriasis is a chronic inflammatory disease characterized by an excessive hyperproliferation of keratinocytes and a combination of genetic, epigenetic, and environmental influences. The pathogenesis of psoriasis is complex and the exact mechanism remains elusive. Objectives: The study of the prevalence of psoriasis will allow the estimation of the number of people suffering from this condition at the national level, as well as the development and validation of a questionnaire to estimate the prevalence and the risk factors associated with the disease. Methods: A quantitative research was conducted at a national level among the target population in order to validate the questionnaire and estimate the national prevalence. Results: Declaratively, the prevalence of psoriasis in the studied group (N = 1500) is 4%, the first symptoms appearing around the age of 50, with a certified diagnosis being made on average at 55 years. The prevalence of psoriasis vulgaris was 4.99%. Conclusions: The results obtained will be useful in guiding future initiatives and communication campaigns related to this condition, and the methodological approach used will provide the opportunity to make recommendations for improving similar initiatives in the future.

Cimifugin relieves pruritus in psoriasis by inhibiting TRPV4

Psoriasis is an immune-mediated chronic inflammatory skin disease characterized by erythema, scales, and infiltration of the skin, which causes deleterious effects on patient quality of life. TRP channel played important roles in the generation and conductance of itch signal . According to our results, psoriasis induced itch was TRPV4 dependent, and TRPV4 expression in both epidermis and DRG were up-regulated in psoriasis. Thus, TRPV4 is an attractive candidate for treating psoriasis induced itch. Cimifugin is a common compound in antipruritic Chinese medicine. In our study, GSK1016790A, a TRPV4 channel specific agonist, induced acute itch was inhibited by cimifugin in a dose-dependent manner. Furthermore, cimifugin treatment reduced the scratching behavior and reversed the TRPV4 up-regulation induced by psoriasis. In particular, cimifugin decreased GSK1016790A induced calcium response both in HaCaT cells and DRG neurons. Importantly, in TRPV4 transfected HEK293 cells, GSK101 induced calcium response was also significantly inhibited by cimifugin pretreatment. Consistent with our calcium imaging result, cimifugin pretreatment also inhibited GSK101 induced inward currents. Our study delineated a new role of TRPV4 in psoriasis and emphasized the antipruritic effect of cimifugin, which opened a new avenue to itch management in psoriasis.

Fixed-dose combination calcipotriol/betamethasone dipropionate foam provides a rapid onset of action, effective itch relief and improves patient quality of life

The physical symptoms of psoriasis vulgaris (chronic plaque psoriasis), such as itch and itch‐related sleep loss, and the psychological impact of visible plaques on the body, all contribute to significantly reduced health‐related quality of life (HRQoL) in patients with psoriasis. In fact, the deterioration of HRQoL in patients with psoriasis is similar to patients with other chronic conditions, such as cancer and cardiovascular diseases. Rapid and effective improvements in HRQoL and itch‐related outcomes would therefore be highly valued by patients and may even improve adherence to treatment. In this article, we summarise previously published data assessing the impact of fixed‐dose combination calcipotriol 50 µg/g plus betamethasone dipropionate 0.5 mg/g cutaneous foam (Cal/BD foam) on itch relief, quality of sleep, onset of action and HRQoL. Findings across multiple analyses indicate that Cal/BD foam provides significant improvements in itch, itch‐related sleep loss and HRQoL compared with vehicle foam or Cal/BD gel comparators. Additionally, the benefits of Cal/BD foam were recorded earlier than these comparators, often within 1 week of treatment, indicating a rapid onset of action. With the published data to hand, it is clear that Cal/BD foam provides significant improvements in the outcomes that matter most to patients and should be considered an effective topical treatment for psoriasis.

Video abstract

Pruritus in psoriasis and atopic dermatitis: current treatments and new perspectives

Psoriasis and atopic dermatitis (AD) are two common chronic inflammatory skin diseases. Although showing different etiology and clinical manifestations, patients with either disease suffer from low health-related quality of life due to pruritus (dermal itch). Recent studies have revealed that more than 85% of psoriasis patients suffer from pruritus, and it is also the dominating symptom of AD. However, as this is a non-life treating symptom, it was partly neglected for years. In this review, we focus on current findings as well as the impact and potential treatments of pruritus in these two skin diseases. We first distinguish the type of itch based on involved mediators and modulators. This clear delineation between the types of pruritus based on involved receptors and pathways allows for precise treatment. In addition, insights into recent clinical trials aimed to alleviate pruritus by targeting these receptors are presented. We also report about novel advances in combinatorial treatments, dedicated to the type of pruritus linked to a causal disease. Altogether, we suggest that only a focused treatment tailored to the primary disease and the underlying molecular signals will provide fast and sustained relief of pruritus associated with psoriasis or AD.

Benefits and harms of NK1 R antagonists in pruritus: A systematic review and meta-analysis

Accumulating evidence has showed the possibility of using NK1R antagonists for the treatment of chronic pruritus. However, the benefit and risk profile of NK1R antagonists-serlopitant and aprepitant for the treatment of pruritus remains unclear. To assess the efficacy and safety of NK1R antagonists-serlopitant and aprepitant in patients with pruritus based on analysis of clinical trials. The current systematic review and meta-analysis was performed according to PRISMA guidelines. A total of 10 randomized clinical trials including 631 patients were enrolled. Four randomized controlled trials investigated the comparative treatment effect of serlopitant on pruritus. Our results showed that serlopitant had reasonable anti-pruritic effectiveness in patients, with mild toxicities. The overall proportion of 4-point improvement of NRS and VAS in serlopitant-treatment group were both significantly higher relative to placebo group (OR 2.345, 95%CI 1.557 to 3.531, P < .001; OR 3.308, 95% CI 1.949 to 5.616, P < .001). Serlopitant treatment was also found to be associated with a significant reduction in NRS score as compared with placebo (SMD -0.381, 95%CI -0.599 to -0.164, P = .001). Six clinical trials reported the treatment effect of aprepitant on pruritus. The meta-analysis result of fixed-effect model showed that there was no significant difference between aprepitant and controlled treatment in terms of improved pruritus VAS score (SMD -0.088, 95%CI -0.384 to 0.207, P = .558). There is promising high-quality evidence regarding the efficacy of serlopitant on pruritus. More large-sample randomized controlled trials with appropriate treatment regimen are urgently needed to further evaluate the effectiveness of aprepitant in pruritus.

Molecular and Cellular Mechanisms of Itch in Psoriasis

Itch (or pruritus) was not previously recognized as a serious symptom of psoriasis. However, approximately 60-90% of psoriatic patients with pruritus have stated that it deteriorates their quality of life. Since conventional antipruritic therapies, such as antihistamines, only exert limited effects, the establishment of a treatment option for itch in psoriasis is urgently needed. Although a definitive drug is not currently available, various itch mediators are known to be involved in pruritus in psoriasis. In this review, we describe the clinical features of pruritus in psoriasis, classify a wide range of itch mediators into categories, such as the nervous, immune, endocrine, and vascular systems, and discuss the mechanisms by which these mediators induce or aggravate itch in the pathophysiology of psoriasis.

The characteristics and impact of pruritus in adult dermatology patients: A prospective, cross-sectional study

BACKGROUND

Pruritus often accompanies chronic skin diseases, exerting considerable burden on many areas of patient functioning; this burden and the features of pruritus remain insufficiently characterized.

OBJECTIVE

To investigate characteristics, including localization patterns, and burden of pruritus in patients with chronic dermatoses.

METHODS

We recruited 800 patients with active chronic skin diseases. We assessed pruritus intensity, localization, and further characteristics. We used validated questionnaires to assess quality of life, work productivity and activity impairment, anxiety, depression, and sleep quality.

RESULTS

Nine out of every 10 patients had experienced pruritus throughout their disease and 73% in the last 7 days. Pruritus often affected the entire body and was not restricted to skin lesions. Patients with moderate to severe pruritus reported significantly more impairment to their sleep quality and work productivity, and they were more depressed and anxious than control individuals and patients with mild or no pruritus. Suicidal ideations were highly prevalent in patients with chronic pruritus (18.5%) and atopic dermatitis (11.8%).

CONCLUSIONS

Pruritus prevalence and intensity are very high across all dermatoses studied; intensity is linked to impairment in many areas of daily functioning. Effective treatment strategies are urgently required to treat pruritus and the underlying skin disease.

Tolerance and efficacy of a new celastrol-containing balm as adjunct care in psoriasis

BACKGROUND

In patients with psoriasis, the non-lesional skin also presents abnormalities, requiring emollient application on the whole body.

OBJECTIVES

To evaluate the tolerance of a new emollient balm containing celastrol, an active ingredient with anti-Th17 immunomodulatory properties used alone or in association with topical or systemic drug treatments or phototherapy, and its efficacy when used alone.

METHODS

Adults with body plaque psoriasis applied the product over the whole body once a day for 4 weeks (balm used alone in 41 patients and with ongoing treatment in 50 patients). At D1, D8 ('balm alone' study) or D15 ('balm in association' study) and D29, the dermatologist rated physical and functional signs and assessed pruritus and body global lesion score (evaluating erythema, induration/thickness, scaling and dryness) in the 'balm alone' study.

RESULTS

No reaction related to the product was reported, and the tolerance was deemed excellent. In the 'balm alone' study, mean pruritus intensity score significantly decreased at D8 (-39%, P < 0.001) and D29 (-60%, P < 0.001) compared with D1, together with the body global lesion score (-24% at D8 and -26% at D29, P < 0.001). In parallel, quality of life improved, as evidenced by a patient-reported outcome questionnaire. Cosmetic acceptability was good.

CONCLUSION

This new emollient balm was very well tolerated by patients with body plaque psoriasis either alone or in association with drug treatment or phototherapy, which is important to ensure long-term compliance. Daily application during one month improved pruritus, physical signs and quality of life.

Emerging drugs for the treatment of chronic pruritic diseases

INTRODUCTION

Chronic pruritus is non-histaminergic and mediated through a complex interplay of peripheral and central immune and neural pathways. Significant developments in the understanding of chronic pruritus have emerged and paved the way for new, emerging therapies.

AREAS COVERED

This review details the emerging drug landscape for chronic pruritus treatment, focusing on monoclonal antibody agents that target key cytokines and their receptors as well as small molecule agents that inhibit mediators of the immune and neural pathways. The article provides background regarding the currently available therapies and the rationale for the development of new agents based on the current market and recent scientific developments.

EXPERT OPINION

Identification of new targets along neuroimmune itch pathways has allowed for the development of targeted drugs which can be utilized for effective therapy. As we enter a new era of chronic itch treatments, we face exciting prospects and challenges.

Inhibition of M/Kv7 Currents Contributes to Chloroquine-Induced Itch in Mice

M/K_v7 potassium channels play a key role in regulation of neuronal excitability. Modulation of neuronal excitability of primary sensory neurons determines the itch sensation induced by a variety of itch-causing substances including chloroquine (CQ). In the present study, we demonstrate that suppression of M/K_v7 channel activity contributes to generation of itch in mice. CQ enhances excitability of the primary sensory neurons through inhibiting M/K_v7 potassium currents in a Ca²⁺ influx-dependent manner. Specific M/K_v7 channel opener retigabine (RTG) or tannic acid (TA) not only reverses the CQ-induced enhancement of neuronal excitability but also suppresses the CQ-induced itch behavior. Systemic application of RTG or TA also significantly inhibits the itch behavior induced by a variety of pruritogens. Taken together, our findings provide novel insight into the molecular basis of CQ-induced itch sensation in mammals that can be applied to the development of strategies to mitigate itch behavior.

Gender differences in psoriasis: a Swiss online psoriasis survey

Physicians' and patients' perspectives can vary significantly. For a long time, physicians considered psoriasis a non-pruritic dermatosis until a survey found pruritus to be the most bothersome symptom among psoriasis patients. In our study, we wanted to get an insight into the factors that affect patients and evaluate whether gender differences exist. A link of an anonymous online survey ( www.fightpsoriasis.ch ) with 24 questions was placed on the website of the Swiss Psoriasis and Vitiligo Patient Association ( www.spvg.ch ) from May 2016 until June 2017. 3164 persons participated in this online survey, of which 1979 were diagnosed with psoriasis. Significantly more females than males were affected by psoriatic pruritus [713 (36%) vs. 500 (25.3%), p ≤ 0.001] and 756 (39.7%) of all patients identified pruritus as the most life quality-limiting factor. Fewer women reported high satisfaction with their therapy compared to men [96 (4.9%) vs. 110 (5.6%), p ≤ 0.015]. Pruritus remains the most bothersome symptom and women were more often affected by it, leading to a lower treatment satisfaction among female patients.

Serlopitant for psoriatic pruritus: A phase 2 randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

Pruritus, a common symptom of psoriasis, negatively affects quality of life; however, treatment of lesional skin does not consistently alleviate psoriatic itch.

OBJECTIVE

To examine the effects of serlopitant, an oral, once-daily neurokinin 1 receptor antagonist, for treatment of psoriatic pruritus in a phase 2, randomized clinical trial (NCT03343639).

METHODS

Patients (n = 204) were randomized to receive serlopitant, 5 mg, or placebo daily for 8 weeks. Eligible adult patients had plaque psoriasis for ≥6 months, plaques covering ≤10% of body surface area, pruritus for ≥4 weeks, and Worst Itch Numeric Rating Scale (WI-NRS) score ≥7 at the initial screening.

RESULTS

Participants (54.2% women) had a mean age of 47.5 years and 85.2% were white. Mean baseline WI-NRS scores were 8.3 for serlopitant and 8.1 for placebo. The WI-NRS 4-point response rate at 8 weeks (primary end point) was 33.3% for serlopitant vs 21.1% for placebo (P = .028); at 4 weeks the rates were 20.8% for serlopitant vs 11.5% for placebo (P = .039). Treatment-related adverse events were reported for 4.9% of serlopitant-treated and 4.0% of placebo-treated patients.

LIMITATIONS

This was a phase 2 study with a small study population. Patients with severe psoriasis were excluded.

CONCLUSION

Serlopitant significantly reduced pruritus associated with mild to moderate psoriasis, supporting continued development of serlopitant for this patient population.