Pruritus and quality of life in moderate-to-severe plaque psoriasis: post hoc explorative analysis from the PRISTINE study

Apremilast, an oral phosphodiesterase 4 inhibitor, improves patient-reported outcomes in the treatment of moderate to severe psoriasis: results of two phase III randomized, controlled trials

Background

Apremilast, an oral phosphodiesterase 4 inhibitor, has an acceptable safety profile and is effective for treatment of plaque psoriasis and psoriatic arthritis.

Objectives

To evaluate the impact of apremilast on health‐related quality of life (HRQOL), general functioning and mental health using patient‐reported outcome (PRO) assessments among patients with moderate to severe plaque psoriasis in the ESTEEM 1 and 2 trials.

Methods

A total of 1255 patients were randomized (2 : 1) to apremilast 30 mg BID or placebo for 16 weeks; all received apremilast through Week 32. PRO assessments included the Dermatology Life Quality Index (DLQI), 36‐Item Short‐Form Health Survey version 2 mental/physical component summary scores (SF‐36v2 MCS/PCS), Patient Health Questionnaire‐8 (PHQ‐8), EuroQol‐5D (EQ‐5D) and Work Limitations Questionnaire‐25 (WLQ‐25). Post hoc analyses examined relationships between Psoriasis Area and Severity Index (PASI) scores and PHQ‐8 in the apremilast‐treated population at Week 16.

Results

Treatment with apremilast improved all HRQOL PROs at Week 16 (vs. placebo), except the SF‐36v2 PCS, and improvements were sustained through Week 32. Mean DLQI and SF‐36v2 MCS improvements exceeded minimal clinically important differences. Changes at Week 16 in PHQ‐8 and PASI were weakly correlated, and only 35.8% of patients who achieved a ≥75% reduction from baseline in PASI score (PASI‐75) with apremilast treatment also achieved PHQ‐8 scores of 0–4.

Conclusions

Apremilast led to improvements in HRQOL PROs vs. placebo in patients with moderate to severe plaque psoriasis.

Reliability and validity of the Psoriasis Itch Visual Analog Scale in psoriasis vulgaris

INTRODUCTION

The single-item Psoriasis Itch VAS was developed to measure itch intensity within the last 24 hours in psoriasis vulgaris to assess treatment benefit. Its psychometric properties were explored in two trials.

METHODS

Data from two randomized, parallel-group phase 3 trials with subjects suffering from psoriasis vulgaris on the body (n = 426, 463) were analyzed. Cross-sectional distributional properties and construct validity of the Psoriasis Itch VAS as well as longitudinal test-retest reliability and sensitivity to change of the Psoriasis Itch VAS were investigated. All statistical tests were two-tailed.

RESULTS

Across both trials, acceptable distributional properties were observed. Convergent-validity correlations between the Psoriasis Itch VAS and other patient-reported and clinician-reported outcomes provided strong endorsement for construct validity as did tests of known-groups validity. Longitudinal measurement properties, involving test-retest reliability and sensitivity to change, also offered evidence for the measurement integrity of the Psoriasis Itch VAS.

DISCUSSION

Results from the assessment of validity, reliability, and sensitivity to change support the use of the Psoriasis Itch VAS to measure itch intensity in psoriasis vulgaris. Data from two trials provided evidence that the Psoriasis Itch VAS is well-defined and reliable for measuring itch in psoriasis vulgaris to assess treatment benefit (i.e. therapeutic response).

[Pruritus in psoriasis : Profile and therapy]

Psoriasis is a common chronic inflammatory disease with an incidence of about 0.5-3 %. Previously psoriasis was not primarily regarded to be associated with pruritus; however, this perception has changed in recent years. Meanwhile data conclusively show that between 64 and 97 % of patients report about pruritus that can be severe in a number of cases. Apart from suffering from psoriasis, the presence of pruritus causes additional stress and leads to a significant impairment of health-related quality of life. Neurogenic inflammation at least in part contributes to the development of pruritus in psoriasis skin lesions. A number of neuropeptides including substance P and calcitonin gene related peptide can act as pro-inflammatory mediators. There is evidence for a dysbalance between κ‑ and µ‑opioid receptors in lesional skin favoring inflammation and pruritus. After clearing of psoriasis lesions, pruritus is relieved as well. Therefore, specific treatment of pruritus is not necessary in general. In cases where severe pruritus is a prominent symptom, targeted therapy with mirtazapin or doxepin or neuroleptic compounds such as pregabalin or gabapentin or drugs affecting the κ‑ und µ‑opioid receptor balance can be administered. Today the importance of pruritus as a prominent symptom of psoriasis lesions has been widely accepted. In recent and running clinical trials with new drugs, pruritus at baseline and the effect of these drugs on pruritus is always assessed. This awareness also fuels basic research about pruritus in psoriasis.

Measurement, Classification and Evaluation of Sleep Disturbance in Psoriasis: A Systematic Review

BACKGROUND

Psoriasis is a long-term immune-mediated inflammatory disorder mainly, but not only, affecting skin, and is associated with significant medical and psychological morbidity. Evidence suggests that sleep is disrupted in psoriasis, however high quality empirical evidence is lacking. Given the importance of sleep for health, characterisation of sleep disruption in psoriasis is an important goal. We therefore conducted a systematic review of the sleep-psoriasis literature.

METHODS

Searches were conducted in Pubmed, SCOPUS and Web of Science from inception to May 2016. Studies were compared against inclusion/exclusion criteria and underwent a quality evaluation. Given the heterogeneity of studies, we conducted a narrative synthesis of the findings.

RESULTS

Searches revealed 32 studies which met our predetermined inclusion/exclusion criteria. Whilst 93.7% of studies reported sleep disruption in this population, ranging from 0.05% to 85.4%, many had important methodological shortcomings. Over half of all quantitative studies (54.8%; 17/31) relied on non-validated measures, contributing to heterogeneity in study findings. In those that employed valid measures, assessing sleep was often not the primary objective. We frequently found the absence of adequate sample size calculations and poor statistical reporting.

CONCLUSION

This review showed that in psoriasis, reported sleep rates of sleep disturbance varied substantially. Most studies lacked a hypothesis driven research question and/or failed to use validated measures of sleep. We were unable to draw firm conclusions about the precise prevalence and nature of sleep disturbance within the psoriasis population. We offer suggestions to help advance understanding of sleep disturbance in psoriasis.

Pruritus in psoriasis: An update

BACKGROUND AND OBJECTIVE

Psoriasis is one of the most common chronic inflammatory skin diseases, found in about 1-3% of the general population. Pruritus affects about 60-90% of patients with psoriasis. The aim of this review was to summarize current knowledge about the pathogenesis and treatment of this symptom in psoriasis patients.

RESULTS

Majority of psoriatic patients consider pruritus as the most bothersome symptom. The pathogenesis of pruritus is still unknown but the major concept of its origin is focused on neurogenic inflammation. Possible itch mediators include neuropeptides released from dermal nerve endings upon various stimuli, which were found to be abnormally expressed in itchy psoriatic plaques. Another important phenomenon supporting the idea of neurogenic inflammation as a key player in pruritus accompanying psoriasis is abnormal innervations of psoriatic skin. Possibly increased innervation density in psoriasis may decrease the threshold for pruritic stimuli. It is also suggested that pruritus in psoriasis might be related to abnormal functioning of the peripheral opioid system. Despite the high frequency of pruritus in psoriasis, to date there is no single antipruritic therapy dedicated specifically to treat itch in this disease.

CONCLUSIONS

Neurogenic inflammation seems to be important for itchiness in psoriasis. Treatment of pruritus in patients with psoriasis should be directed towards the resolution of skin lesions, as disease remission usually is linked with pruritus relief.

Psoriasis and sleep disorders: A systematic review

Psoriasis is an immune-mediated chronic inflammatory disorder which manifests as dermatologic lesions, and psoriatic arthritis (PsA) in about 30% of cases. Psoriasis is associated with multiple comorbidities including metabolic syndrome, hypertension, diabetes, cardiovascular events, obesity and psychiatric disorders, which can all affect the course of sleep disorders. A systematic review of the literature on the relationship between psoriasis, PsA, and formal sleep disorders identified 33 studies. There is an increased prevalence of obstructive sleep apnea (OSA) with 36%-81.8% prevalence in psoriasis versus 2%-4% in the general population. There was also an increase in the prevalence of restless legs syndrome of 15.1%-18% in psoriasis versus 5%-10% in European and North American samples. The wide variety of insomnia criteria used in studies resulted in an insomnia prevalence of 5.9%-44.8% in psoriasis, which is insufficient to show an elevated prevalence when the general population has a 10% prevalence of chronic insomnia and 30-35% prevalence of transient insomnia. There is evidence that symptoms of insomnia in psoriasis are directly mediated by pruritus and pain. Treatments that decrease the cutaneous symptoms in psoriasis were successful in mitigating insomnia, but did not show improvements in OSA where the relationship with psoriasis is multifactorial.

Nalfurafine hydrochloride to treat pruritus: a review

Uremic pruritus has a great negative influence on quality of life in hemodialysis (HD) patients and, importantly, negatively affects mortality risk. Recently, nalfurafine hydrochloride, an opioid κ-selective agonist, has been officially approved for resistant pruritus in HD patients on the basis of a well-evidenced clinical trial in Japan. From clinical observation, it has been suggested that the upper neuron system plays a role in its pathogenesis. According to previous experimental results, using mice injected with opioids, dynorphin suppresses itch through binding κ-opioid receptors, suggesting that κ-opioid opioid receptor agonists act as potential therapeutic reagents for pruritus in HD patients. In Japan, a large-scale placebo-controlled study was performed to examine the efficacy and safety of oral nalfurafine hydrochloride for intractable pruritus in 337 HD patients. Two daily doses of 2.5 or 5 μg nalfurafine or placebo were orally administered for 2 weeks, and clinical responses were analyzed. The results showed that the mean decrease in the visual analog scale for pruritus from baseline was 22 mm in the 5 μg nalfurafine hydrochloride group (n=114) and 23 mm in the 2.5 μg group (n=112). These reductions were statistically significant compared with 13 mm, which is the mean decrease of visual analog scale in the placebo group (n=111), demonstrating that nalfurafine is an effective and safe drug for uremic pruritus in HD patients. Moreover, another open-label trial (n=145) examining the long-term effect of 5 μg oral nalfurafine revealed the maintenance of the antipruritic effect of nalfurafine for 52 weeks. In addition, on the basis of recent data showing κ-opioid receptor expression in the epidermis of atopic dermatitis and psoriasis, nalfurafine hydrochloride also can be potentially used for these two skin diseases.