Itch and scratching as predictors of time to clearance of psoriasis with narrow-band ultraviolet B therapy

Quality of Life Benefit and Clinical Predictors of Complete Skin Clearance in Psoriasis: A Multicenter, Prospective, Real-World Study

BACKGROUND

Newer biologics, such as interleukin (IL)-17 inhibitors, make it possible to achieve complete skin clearance (CSC) in patients with moderate-to-severe psoriasis. However, the clinical meaningfulness and predictive factors of CSC in daily practice have not yet been fully investigated.

OBJECTIVE

The study was conducted to, first, assess the impact of CSC on quality of life (QoL) improvements compared with treatment responses without clearance and, second, identify clinical parameters as predictors of CSC response in psoriasis patients treated with ixekizumab.

METHODS

Patients attending 26 dermatology centers across China were recruited into this real-world setting between August 2020 and May 2022. Prospective cohort study in which response to ixekizumab was assessed using the Psoriasis Area and Severity Index (PASI) and Dermatology Quality of Life Index (DLQI). The absolute DLQI score and DLQI (0) response at week 12 were compared between groups achieving various levels of skin clearance. A stepwise logistic regression analysis was applied to identify which baseline clinical characteristics were predictive factors for CSC.

RESULTS

After 12 weeks of treatment, 226 of 511 (44.2%) patients achieved CSC, defined as 100% improvement in PASI score (PASI-100). A significantly higher proportion of patients with CSC versus almost clear skin (PASI 90-99) achieved DLQI score of 0, corresponding to the experience of no impairment on QoL (54.4% vs. 37.7%, p = 0.001). Females patients were more likely than males to achieve CSC response (odds ratio [OR] = 1.83; 95% confidence interval [CI]: 1.24-2.70), while previous biologic treatment (OR = 0.43; 95% CI: 0.24-0.81) and joint affected (OR = 0.61; 95% CI: 0.42-0.89) were significantly associated with less CSC response.

CONCLUSIONS

This study highlights the fact that clinical parameters are important in determining CSC response in psoriasis. In daily practice, achieving CSC represents a clinically meaningful treatment goal, especially from the patient perspective.

Treatment Options for Troublesome Itch

Itch (or pruritus) is an unpleasant sensation, inducing the desire to scratch. It is also a major and distressing symptom of many skin and systemic diseases. The involvement of histamine, which is a major itch mediator, has been extensively examined. Recent studies suggest that histamine-independent pathways may play roles in chronic itch. Therefore, antihistamines are not always effective in the treatment of patients with chronic itch. The development of biologics and κ-opioid receptor (KOR) agonists has contributed to advances in the treatment of itch; however, since biologics are expensive for patients to purchase, some patients may limit or discontinue their use of these agents. Furthermore, KOR agonists need to be prescribed with caution due to risks of side effects in the central nervous system. Janus kinase (JAK) inhibitors are sometimes associated with side effects, such as infection. In this review, we summarize antidepressants, antineuralgics, cyclosporine A, antibiotics, crotamiton, phosphodiesterase 4 inhibitor, botulinum toxin type A, herbal medicines, phototherapy, and acupuncture therapy as itch treatment options other than antihistamines, biologics, opioids, and JAK inhibitors; we also explain their underlying mechanisms of action.

Itch: an under-recognized problem in psoriasis

Psoriasis has historically been considered a nonpruritic dermatosis, in contrast with atopic dermatitis. Thus, itch has often been underappreciated and overlooked in psoriasis. However, increasing evidence over the past decade has shown that itch can be one of the most prevalent and burdensome symptoms associated with psoriasis, affecting almost every patient to some degree. Itch can involve the entire body, although it predominantly affects the legs, hands, back, body and especially the scalp. Uncontrolled itch can significantly impact all aspects of the well-being and quality of life of the patient. While there has been some progress in trying to better understand the pathophysiology of itch in psoriasis, more research effort and interest are needed. This under-recognition of itch in psoriasis is clearly reflected in the dearth of treatment options targeting itch despite significant advancement in treating the lesions themselves. Recently, however, clinical studies have begun to include itch as a study outcome. The resulting data have demonstrated concomitant antipruritic benefits and improved Psoriasis Area and Severity Index (PASI) scores with mainstay treatments for psoriasis, such as topical corticosteroids and vitamin D analogs, phototherapies, and various systemics and biologics. This article takes a closer look at this debilitating symptom, reviewing the available epidemiology data for psoriatic itch, presenting the current understanding of psoriatic itch pathophysiology and highlighting important clinical data for various treatment options for itch. Practical considerations for increasing the recognition of itch as well as improving its management in psoriasis are also provided.

Metabolic syndrome affects narrow-band UVB phototherapy response in patients with psoriasis

Psoriasis is a chronic inflammatory skin disease. Metabolic syndrome (MS) is a combination of central obesity, dyslipidemia, glucose intolerance, and elevated blood pressure. Many epidemiological surveys have revealed the association of psoriasis with MS. Narrowband ultraviolet radiation b (NB-UVB) is an effective and widely used treatment for psoriasis. The purpose of this study was to investigate whether the presence of MS in patient with psoriasis affects NB-UVB treatment and whether this syndrome correlates with systemic inflammation.From June 2016 to December 2016, 243 adults with a diagnosis of psoriasis vulgaris eligible to treatment with NB-UVB were admitted to the phototherapy unit of Dermatology department, Chinese PLA General Hospital. Fifty-five included patients were grouped based on the presence of MS. They accepted the treatment of NB-UVB and the following data were collected: serum levels of IL-17 (interleukin), TNF-α (tumor necrosis factor) and IL-6, Psoriasis Area and Severity Index (PASI) scores before and after 10 sections of NB-UVB treatment.Significant PASI improvement was observed in psoriatic patients without MS after 10 sections of phototherapy, while patients with MS showed a less improvement (P < .001). There was statistically significant difference in percentage of patients achieving 50% reduction in PASI scores between the 2 groups (P < .05). Multivariate logistic regression analysis showed MS was an independent factor that affecting the treatment of NB-UVB (P < .05). Psoriatic patients with MS showed a much less reduction of IL-17 and IL-6 before and after 10 sections of NB-UVB treatment respectively than patients without MS (P < .05).Psoriatic patients with MS have poorer improvement in comparison those without MS using NB-UVB treatment. MS was an independent factor that affecting the treatment of NB-UVB. In addition, psoriatic patients with MS showed a much less reduction of systemic biomarkers (interleukin-IL-17, TNF-α, IL-6) than patients without MS. Namely, they may need a longer course of treatment to achieve improved skin lesions.

Is it Useful to Calculate Minimal Erythema Dose Before Narrowband UV-B Phototherapy?

INTRODUCTION AND OBJECTIVES

The starting dose for narrowband UV-B phototherapy is determined by a patient's skin phototype or minimal erythema dose (MED). Calculation of MED identifies patients with unsuspected photosensitivity. The aim of this study was to investigate the influence of factors such as concomitant use of photosensitizing agents, diagnosis, and combination with acitretin in patients with psoriasis on the frequency and severity of adverse effects in patients with a low MED to narrowband UV-B phototherapy.

MATERIAL AND METHODS

We undertook a retrospective observational cohort study between February 1, 2009 and March 31, 2015. MED values were classified as normal or low.

RESULTS

In total, 302 patients with different skin conditions started narrowband UV-B phototherapy at a dose determined by their MED. No differences were found between patients with a low MED and those with a normal MED for number of drugs taken (P=.071) or use of photosensitizing agents (P=0.806). Following adjustment for age, sex, and phototype, the multivariate analysis showed that psoriasis exerted a protective effect against a low MED (OR=0.31 [95% CI, 0.16-0.58]). No significant risk of erythema or pruritus was detected in patients with a low MED (OR=1.68; 95% CI, 0.91-3.29 and OR=2.04; 95% CI, 0.99-4.22, respectively).

CONCLUSIONS

Psoriasis protects against a low MED. Although erythema and pruritus were more common in patients with a low MED, the differences were not significant.

Current and Emerging Therapies for Itch Management in Psoriasis

Pruritus is a common and significant symptom among patients with psoriasis. Pruritus is often present beyond the borders of psoriatic plaques, and frequently affects the scalp and genital regions. Psoriatic itch may be severe and can profoundly affect quality of life and sleep, even in the context of mild-to-moderate disease. These features often make the treatment of psoriatic pruritus challenging. However, there are a variety of effective topical and systemic treatment modalities available to address this symptom. While there remains a need for treatments that specifically target psoriatic itch, newly licensed therapies including secukinumab, ixekizumab and apremilast have been shown to rapidly and effectively mediate itch reduction.

Does psychosocial stress play a role in the exacerbation of psoriasis?

It is widely accepted that psychosocial stress can result from the daily strains of living with a diagnosis of psoriasis. There is now an evolving body of work to suggest that psychosocial stress may also play a role in the exacerbation of psoriasis. We discuss the historical evidence supporting a temporal relationship between psychosocial stress and the exacerbation of psoriasis. The underlying pathophysiological mechanisms by which this occurs are largely unknown, but current evidence points towards a role for nerve-related factors, namely their interaction with mast cells and the potentiation of neurogenic inflammation in this regard. It is also likely that the physiological stress response in patients with psoriasis differs from that in healthy individuals, as evidenced by alterations in the hypothalamic-pituitary-adrenal axis and sympathetic-adrenal-medullary system function. Psychological stress results in a redistribution of leucocytes with increased trafficking of inflammatory cells into the skin, which may exacerbate psoriasis. Langerhans cells play a role in the stress response of normal skin; their function in the stress response of patients with psoriasis is open to speculation. We discuss the influence of stress reactivity in patients with psoriasis and the impact of stress reduction strategies in the management of psoriasis. Finally, we suggest potentially fruitful areas for future research.

Quality of life and sexual health in patients with genital psoriasis

BACKGROUND

Knowledge about quality of life and sexual health in patients with genital psoriasis is limited.

OBJECTIVES

We studied quality of life and sexual function in a large group of patients with genital psoriasis by means of validated questionnaires. In addition, we evaluated whether sufficient attention is given by healthcare professionals to sexual problems in patients with psoriasis, as perceived by the patients.

METHODS

A self-administered questionnaire was sent to 1579 members of the Dutch Psoriasis Association. Sociodemographic patient characteristics, medical data and scores of several validated questionnaires regarding quality of life (Dermatology Life Quality Index) and sexual health (Sexual Quality of Life Questionnaire for use in Men, International Index of Erectile Function, Female Sexual Distress Scale and Female Sexual Function Index) were collected and analysed.

RESULTS

This study (n = 487) shows that psoriasis has a detrimental effect on quality of life and sexual health. Patients with genital lesions reported even significantly worse quality of life than patients without genital lesions (mean ± SD quality of life scores 8·5 ± 6·5 vs. 5·5 ± 4·6, respectively, P < 0·0001). Sexual distress and dysfunction are particularly prominent in women (reported by 37·7% and 48·7% of the female patients, respectively). Sexual distress is especially high when genital skin is affected (mean ± SD sexual distress score in patients with genital lesions 16·1 ± 12·1 vs. 10·1 ± 9·7 in patients without genital lesions, P = 0·001). The attention given to possible sexual problems in the psoriasis population by healthcare professionals is perceived as insufficient by patients.

CONCLUSIONS

In addition to quality of life, sexual health is diminished in a considerable number of patients with psoriasis and particularly women with genital lesions have on average high levels of sexual distress. We underscore the need for physicians to pay attention to the impact of psoriasis on psychosocial and sexual health when treating patients for this skin disease.

Inhibitory effects of UV-based therapy on dry skin-inducible nerve growth in acetone-treated mice

BACKGROUND

UV-based therapy has anti-pruritic effects in inflammatory skin diseases, such as atopic dermatitis and psoriasis. These anti-pruritic effects may be partly due to inhibition of intraepidermal nerve growth, but they have not been fully characterized.

OBJECTIVE

This study was performed to characterize the anti-nerve growth effects of UV-based therapies in acetone-treated mice as an acute dry skin model.

METHODS

Nerve fibers penetrate into the epidermis 24h after acetone treatment in mice, and nerve growth peaks 48h after acetone treatment. To investigate the effects of UV-based therapies on the epidermal nerve fibers, including combination treatment with corticosteroid ointment, the mice were treated with psoralen ultraviolet A (PUVA), PUVA and betamethasone valerate ointment (PUVA+BV), narrowband ultraviolet B (NB-UVB), or an excimer lamp. Each therapy was provided 24h after acetone treatment, and skin samples were taken 48h later. Nerve fiber densities and expression levels of nerve growth factor (NGF) and semaphorin 3A (Sema3A) in the epidermis were examined by immunohistochemistry.

RESULTS

Penetration of nerve fibers into the epidermis was observed in the acetone-treated mice, concomitant with increased NGF and decreased Sema3A levels in the epidermis. The acetone-induced intraepidermal nerve growth was significantly decreased by PUVA, PUVA+BV, NB-UVB, and excimer lamp treatments compared with controls. In addition, PUVA+BV and NB-UVB normalized the abnormal expression of NGF and Sema3A in the epidermis, but no such normalization was observed with excimer lamp treatment.

CONCLUSION

UV-based therapies, especially NB-UVB and excimer lamp treatments, may be effective therapeutic methods for pruritus involving epidermal hyperinnervation.

Tumor necrosis factor-alpha-converting enzyme as a potential mediator of the influence of smoking on the response to treatment with narrowband ultraviolet B in psoriasis patients

PURPOSE

The aim of the study was to analyze the relationship between smoking and the treatment with narrowband ultraviolet B (NB-UVB) in psoriasis patients and to examine the role of the soluble tumor necrosis factor-alpha receptor type one (sTNF-R1) in plasma and that of TNF-alpha-converting enzyme (TACE) released from peripheral blood mononuclear cells (PBMC) in this relationship.

METHODS

The study has been conducted among 45 inpatients with plaque-type psoriasis vulgaris and 36 inpatients with other chronic inflammatory skin disorders from similar social background (controls). Taking into account the number of cigarettes smoked daily and the duration of smoking, subjects were classified as mild, moderate and heavy smokers. The severity of psoriasis was assessed using psoriasis area and severity index (PASI) score, concentrations of sTNF-R1 and TACE (expressed in ng/ml)--with quantitative sandwich enzyme immunoassays before (T(0)) and after 20 NB-UVB irradiations (T(20)).

RESULTS

The pretreatment concentration of sTNF-R1 was 2.55+/-0.17 in patients and 1.79+/-0.13 in controls (P<0.05) and that of TACE - 2.62+/-0.34 and 1.29+/-0.25, P<0.05, respectively. PASI score correlated with sTNF-R1 and with TACE concentrations (R=0.40 and R=0.38, P<0.05, respectively). PASI score, sTNF-R1 and TACE concentrations were similar in mild, moderate and in heavy smokers. PASI score and TACE concentration declined significantly after treatment in three groups; the lowest TACE concentration at T(20) was noticed in mild smokers, the highest in heavy smokers (0.86+/-0.26 and 1.91+/-0.20, P<0.05, respectively). The post-treatment PASI score correlated with the intensity of smoking and with TACE concentration (R=0.50 and R=0.47, P<0.05, respectively). The strong correlation between the pretreatment TACE concentration and the treatment outcome was observed in heavy smokers (R=0.63, P<0.05).

CONCLUSIONS

The baseline TACE concentration in PBMC may be of value in predicting the response to the treatment with NB-UVB in smoking psoriasis patients. Smoking may adversely influence this treatment and TACE may be one of mediators in this influence.

Foxp3+ regulatory T cells and related cytokines differentially expressed in plaque vs. guttate psoriasis vulgaris

BACKGROUND

Differences in the number of Foxp3+ regulatory T cells (Tregs) in lesional skin and peripheral blood and their functioning in plaque vs. guttate psoriasis have not been reported.

OBJECTIVES

To investigate whether there is a differential expression of Foxp3+ Tregs and a differential regulation of inflammatory cytokines in plaque vs. guttate psoriasis vulgaris.

METHODS

The number and the percentage of Foxp3+ cells in different phases of skin lesions of patients with plaque and guttate psoriasis vulgaris were assessed by immunohistochemical staining. The expression of Foxp3 and interleukin (IL)-17 protein in CD4 populations was measured by flow cytometry. Inflammatory cytokine production by transforming growth factor-beta1-induced Foxp3+ Tregs was assessed in an in vitro study. The cytokines in supernatant and serum were determined by enzyme-linked immunosorbent assay.

RESULTS

The percentage of Foxp3+ CD3+ cells in the papillary layer was higher than in the reticular layer of dermis and in epidermis (P < 0.05). The numbers of Foxp3+ Tregs in skin lesions and peripheral blood were higher in plaque than in guttate psoriasis, whereas the percentage of IL-17+ CD4+ cells was higher in guttate than in plaque psoriasis (P < 0.05). The numbers of Foxp3+ cells were positively correlated with the Psoriasis Severity Index score of skin lesions (P < 0.0001), and the percentages of Foxp3+ CD4+ cells in peripheral blood were positively correlated with the Psoriasis Area and Severity Index score of patients (P < 0.05). The inhibitory functions of Tregs to IL-17 and IL-6 in guttate psoriasis and to tumour necrosis factor-alpha in plaque psoriasis were deficient.

CONCLUSIONS

Differential expression and regulatory functioning for inflammatory cytokine production by Foxp3+ Tregs may imply a different immunopathogenesis for plaque and guttate psoriasis.