Skin Pain in Patients with Atopic Dermatitis or Psoriasis: A Web-based Survey

Similarities and differences in peripheral itch and pain pathways in atopic dermatitis

Atopic dermatitis (AD) is predominantly characterized by intense itching, but concomitant skin pain is experienced by more than 40% of patients. Patients with AD display considerable somatosensory aberrations, including increased nerve sensitivity to itch stimuli (hyperknesis), perception of itch from innocuous stimuli (alloknesis), or perception of pain from innocuous stimuli (allodynia). This review summarizes the current understanding of the similarities and differences in the peripheral mechanisms underlying itch and pain in AD. These distinct yet reciprocal sensations share many similarities in the peripheral nervous system, including common mediators (such as serotonin, endothelin-1, IL-33, and thymic stromal lymphopoietin), receptors (such as members of the G protein-coupled receptor family and Toll-like receptors), and ion channels for signal transduction (such as certain members of the transient receptor potential [TRP] cation channels). Itch-responding neurons are also sensitive to pain stimuli. However, there are distinct differences between itch and pain signaling. For example, specific immune responses are associated with pain (type 1 and/or type 3 cytokines and certain chemokine C-C [CCL2, CCL5] and C-X-C [CXCL] motif ligands) and itch (type 2 cytokines, including IL-31, and periostin). The TRP melastatin channels TRPM2 and TRPM3 have a role in pain but no known role in itch. Activation of μ-opioid receptors is known to alleviate pain but exacerbate itch. Understanding the connection between itch and pain mechanisms may offer new insights into the treatment of chronic pain and itch in AD.

Cutaneous Components Leading to Pruritus, Pain, and Neurosensitivity in Atopic Dermatitis: A Narrative Review

Atopic dermatitis (AD) is a chronic, relapsing immunoinflammatory skin condition characterized by sensations such as pruritis, pain, and neuronal hypersensitivity. The mechanisms underlying these sensations are multifactorial and involve complex crosstalk among several cutaneous components. This review explores the role these components play in the pathophysiology of atopic dermatitis. In the skin intercellular spaces, sensory nerves interact with keratinocytes and immune cells via myriad mediators and receptors. These interactions generate action potentials that transmit pruritis and pain signals from the peripheral nervous system to the brain. Keratinocytes, the most abundant cell type in the epidermis, are key effector cells, triggering crosstalk with immune cells and sensory neurons to elicit pruritis, pain, and inflammation. Filaggrin expression by keratinocytes is reduced in atopic dermatitis, causing a weakened skin barrier and elevated skin pH. Fibroblasts are the main cell type in the dermis and, in atopic dermatitis, appear to reduce keratinocyte differentiation, further weakening the skin barrier. Fibroblasts and mast cells promote inflammation while dermal dendritic cells appear to attenuate inflammation. Inflammatory cytokines and chemokines play a major role in AD pathogenesis. Type 2 immune responses typically generate pruritis, and the type 1 and type 3 responses generate pain. Type 2 responses and increased skin pH contribute to barrier dysfunction and promote dysbiosis of the skin microbiome, causing the proliferation of Staphyloccocus aureus. In conclusion, understanding the dynamic interactions between cutaneous components in AD could drive the development of therapies to improve the quality of life for patients with AD.

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.

Pain associated with psoriasis: a qualitative study

BACKGROUND

Pain is a major factor in the psychosocial impact of psoriasis. There is a paucity of qualitative reports of dermatologists' views on psoriasis-related pain.

OBJECTIVES

The aim of this study was to explore the views of dermatologists on the presence and importance of pain associated with psoriasis.

METHODS

This qualitative study, based on semi-structured interviews, included dermatologists from different cities working in the hospital and private sector in Croatia between May and July, 2022. We collected demographic and occupational data on participants and information about their experiences and attitudes toward psoriasis-related pain. Data were analysed by applying interpretative descriptive and thematic analysis using the 4-stage method for systematic text condensation.

RESULTS

We included 19 dermatologists, all women, aged 38 (range: 31 to 63 years). Most dermatologists acknowledged the presence of pain in patients with psoriasis. They indicated that they sometimes do not sufficiently address this pain in daily practice. Some indicated that pain was a neglected symptom in psoriasis, while for others it was not crucial. Most indicated that it is necessary to focus more on psoriasis-related pain in clinical practice, to disambiguate between skin pain and joint pain in psoriatic conditions, and to better educate family physicians about psoriasis-related pain. They emphasized the importance of considering pain during psoriatic patient assessment and management. Further research on psoriasis-related pain was suggested.

CONCLUSIONS

More emphasis is needed on psoriasis-related pain for effective management of psoriasis, informing decision-making in the context of patient-centric care and improving the quality of life in patients with psoriasis.

Speed of clinical improvement in the real-world setting from patient-reported Psoriasis Symptoms and Signs Diary: Secondary outcomes from the Psoriasis Study of Health Outcomes through 12 weeks

BACKGROUND

Rapid skin improvement is a key treatment goal of patients with moderate-to-severe psoriasis (PsO).

OBJECTIVES

To compare the speed of clinical improvement of approved biologics on the symptoms and signs of psoriasis assessed by patients using the validated Psoriasis Symptoms and Signs Diary (PSSD) through 12 weeks.

METHODS

Psoriasis Study of Health Outcomes (PSoHO) is an international, prospective, non-interventional study that compares the effectiveness of anti-interleukin (IL)-17A biologics versus other biologics, together with pairwise comparisons of ixekizumab versus five individual biologics in patients with PsO. Using the PSSD 7-day recall period, patients assessed the symptoms (itch, skin tightness, burning, stinging and pain) and signs (dryness, cracking, scaling, shedding/flaking, redness and bleeding) of their psoriasis (0-10). Symptom and sign summary scores (0-100) are derived from the average of individual scores. Percentage change in summary scores and proportion of patients with clinically meaningful improvements (CMI) in PSSD summary and individual scores are evaluated weekly. Longitudinal PSSD data are reported as observed with treatment comparisons analysed using mixed model for repeated measures (MMRM) and generalized linear mixed models (GLMM).

RESULTS

Across cohorts and treatments, eligible patients (n = 1654) had comparable baseline PSSD scores. From Week 1, the anti-IL-17A cohort achieved significantly larger score improvements in PSSD summary scores and a higher proportion of patients showed CMIs compared to the other biologics cohort through 12 weeks. Lower PSSD scores were associated with a greater proportion of patients reporting their psoriasis as no longer impacting their quality-of-life (DLQI 0,1) and a high level of clinical response (PASI100). Results also indicate a relationship between an early CMI in PSSD score at Week 2 and PASI100 score at Week 12.

CONCLUSIONS

Treatment with anti-IL-17A biologics, particularly ixekizumab, resulted in rapid and sustained patient-reported improvements in psoriasis symptoms and signs compared with other biologics in a real-world setting.

Sexual Dysfunction in Women and Men with Psoriasis: A Cross-Sectional Questionnaire-Based Study

Background and objectives: Psoriasis can lead to feelings of stigmatization, hinder social functioning, and impair quality of life. Psoriasis can also affect sexual activity, but there is still little research on this topic. The present study investigated whether and to what extent psoriasis, its severity, location and extent of skin lesions affect sexual dysfunction. Materials and Methods: A total of 45 women and 64 men aged 18 to 73 years hospitalized for psoriasis exacerbations were included in the study. Psoriasis severity, as assessed by the Psoriasis Area and Severity Index (PASI), ranged from 0.2 to 65 points (mean: 17.0 ± 14.9 points). After collecting demographic and clinical data, each subject was asked to complete the Dermatology Life Quality Index, the 11-item Sexual Life Questionnaire and the International Index of Erectile Function (only men). Results: Our study found that more than 90% of the patients surveyed felt at least a slight unattractiveness due to psoriasis. In approximately 80% of the subjects, the skin lesions at least occasionally affected their sex life, and more than 50% at least sometimes avoided sexual contact. The location of psoriasis, particularly in the genital area (p = 0.01), on the face (p = 0.03) and hands (p = 0.05), also had a significant impact on the level of sexual problems. Psoriasis has a significant impact on the quality of life (QoL), and a deterioration in QoL was strongly correlated with sexual dysfunction (r = 0.6, p < 0.001), PASI scores (r = 0.36, p < 0.001), self-assessment of psoriasis severity and location of psoriatic lesions. Conclusions: Psoriasis leads to various limitations, especially in the sphere of sexual life. Patients with psoriasis feel stigmatized, have lowered self-esteem and consequently experience significant sexual problems. Awareness of the co-occurring psychological aspect of psoriasis and the routine use of validated scales in dermatology practice should contribute to the rapid identification of patients with sexual dysfunction.

Characteristics, mechanism, and management of pain in atopic dermatitis: A literature review

Background

Atopic dermatitis (AD) is a chronic, pruritic, immune‐mediated inflammatory disease. Developments in basic science and clinical research have increased our understanding of AD. Although pain as a symptom of AD is underemphasized in previous studies, multiple researchers address pain as a frequent burden of AD. However, the exact role of pain in AD is not fully understood.

Aims

Our review aimed to summarize the current evidence focusing on characteristics, mechanism, and management of pain in AD.

Materials & Methods

We conducted a thorough literature review in the PubMed database to figure out different aspects discussing pain in AD, including pain symptoms, burden, the relationship between pain and itch, mechanism, and pain management in AD.

Results and Conclusion

AD patients affected by skin pain vary from 42.7%‐92.2% with remarkable intensity and heavy burden. Skin pain and itch interacted both in symptoms and mechanisms. Atopic skin with the impaired barrier, neurogenic inflammation mediators, peripheral and central sensitization of pain may possibly explain pain mechanism in AD. Future research is needed to clarify the commonality and disparity of pain and itch in AD in order to seek efficacious medications and treatment.

Disease burden, symptoms, and use of analgesics in patients with psoriasis with or without psoriatic arthritis: A cross-sectional study

BACKGROUND

Patients with psoriasis have an impaired quality of life and higher use of analgesics than the general population. Whether such use is due to skin pain or a consequence of joint pain resulting from psoriatic arthritis (PsA) is not clear.

OBJECTIVES

To assess symptoms, disease burden, and use of analgesics in patients with psoriasis with and without PsA.

METHOD

Symptoms, general health (EurQol 5-dimension and 5-levels), and use of analgesics were assessed in patients with psoriasis and the general population from the Danish Skin Cohort.

RESULTS

We included 4016 patients with psoriasis (847 with concomitant PsA) and 3490 reference individuals. For patients with psoriasis having PsA, itch, skin pain, and/or joint pain was associated with worse general health. Use of opioids within 12 months was observed among 9.0% of the general population, 14.2% of patients with psoriasis without PsA, and 22.7% of patients with concomitant PsA. Of the symptoms, only joint pain was associated with use of analgesics (odds ratio, 3.72 (2.69-5.14); P < .0001).

LIMITATIONS

Cross-sectional design.

CONCLUSION

Patients with psoriasis (especially concomitant PsA) have a higher use of analgesics compared with the general population, which appears to be a result of increased joint pain.