NNT mediates redox-dependent pigmentation via a UVB- and MITF-independent mechanism.

Ultraviolet (UV) light and incompletely understood genetic and epigenetic variations determine skin color. Here we describe an UV- and microphthalmia-associated transcription factor (MITF)-independent mechanism of skin pigmentation. Targeting the mitochondrial redox-regulating enzyme nicotinamide nucleotide transhydrogenase (NNT) resulted in cellular redox changes that affect tyrosinase degradation. These changes regulate melanosome maturation and, consequently, eumelanin levels and pigmentation. Topical application of small-molecule inhibitors yielded skin darkening in human skin, and mice with decreased NNT function displayed increased pigmentation. Additionally, genetic modification of NNT in zebrafish alters melanocytic pigmentation. Analysis of four diverse human cohorts revealed significant associations of skin color, tanning, and sun protection use with various single-nucleotide polymorphisms within NNT. NNT levels were independent of UVB irradiation and redox modulation. Individuals with postinflammatory hyperpigmentation or lentigines displayed decreased skin NNT levels, suggesting an NNT-driven, redox-dependent pigmentation mechanism that can be targeted with NNT-modifying topical drugs for medical and cosmetic purposes.

Combined genome-wide association study of 136 quantitative ear morphology traits in multiple populations reveal 8 novel loci.

Human ear morphology, a complex anatomical structure represented by a multidimensional set of correlated and heritable phenotypes, has a poorly understood genetic architecture. In this study, we quantitatively assessed 136 ear morphology traits using deep learning analysis of digital face images in 14,921 individuals from five different cohorts in Europe, Asia, and Latin America. Through GWAS meta-analysis and C-GWASs, a recently introduced method to effectively combine GWASs of many traits, we identified 16 genetic loci involved in various ear phenotypes, eight of which have not been previously associated with human ear features. Our findings suggest that ear morphology shares genetic determinants with other surface ectoderm-derived traits such as facial variation, mono eyebrow, and male pattern baldness. Our results enhance the genetic understanding of human ear morphology and shed light on the shared genetic contributors of different surface ectoderm-derived phenotypes. Additionally, gene editing experiments in mice have demonstrated that knocking out the newly ear-associated gene (Intu) and a previously ear-associated gene (Tbx15) causes deviating mouse ear morphology.

From decision to reflection: understanding the experiences and unmet care needs of patients treated with immunotherapy for melanoma in the adjuvant or metastatic setting.

BACKGROUND: Despite increased use of immune checkpoint inhibitors (ICIs) in patients with advanced melanoma, little is known about patient experiences during this treatment. This study aimed to gain an in-depth understanding of experiences and unmet care needs of patients treated in the adjuvant or metastatic setting for advanced melanoma regarding their ICI treatment trajectory. METHODS: Interviews and focus groups were conducted among 35 patients treated with ICIs in the adjuvant setting for completely resected stage III (n = 14), or in the metastatic setting for irresectable stage IV (n = 21) melanoma. A thorough thematic content analysis was conducted. RESULTS: Three main themes were identified. When (1) dealing with uncertainty in the decision-making process, adjuvant patients explored the pros and cons, whereas metastatic patients considered immunotherapy their only viable option. Both groups expressed the need for additional guidance. In (2) navigating the immunotherapy course, both perceived the trajectory as intense, experienced a major impact on their and their (close) relatives' lives, and felt the need to (re)gain control. When (3) looking back on the immunotherapy experience, metastatic patients generally felt relieved, while among adjuvant patients, feelings of doubt regarding their choice for ICIs were also reported. CONCLUSIONS: ICI treatment is perceived as intensive for both patient groups, facing both comparable and distinct challenges throughout the treatment trajectory, underscoring the need for stage-specific, individualised guidance. Options regarding flexible follow-ups, low-threshold contact and psychosocial support throughout the treatment trajectory should be explored.

Global epidemiology of actinic keratosis in the general population: a systematic review and meta-analysis.

BACKGROUND: Actinic keratosis (AK) is a common dermatological condition, and among the most common dermatological diagnoses in older populations. Although the prevalence of AK depends on demographic and environmental factors, little is known about the global context of AK. OBJECTIVES: To provide a comprehensive and updated analysis of the global prevalence rate and incidence of AK in the general population through a systematic review and meta-analysis, and - through subgroup analyses - to identify high-risk phenotypes, demographic and lifestyle risk factors and regional variations in disease prevalence. METHODS: A systematic search of Embase, MEDLINE, Web of Science and Google Scholar was performed on 20 May 2022. Two reviewers independently screened and assessed the quality of each study using a validated critical appraisal checklist. Epidemiological measurements (e.g. prevalence) from individual studies performed in the general population were then pooled in a random-effects meta-analysis. Subgroup analyses (i.e. population age, geographical region, occupation, sex and study quality) were conducted. RESULTS: Of the 65 articles that made it through the full-text screening, 60 reported a point prevalence. A meta-analysis of these articles yielded an overall point prevalence of 14% [95% confidence interval (CI) 14-15]. In further analyses, the calculated prevalence rate varied depending on subgroup. The pooled incidence rate from the seven eligible studies analysed was 1928 per 100 000 person-years (PY; 95% CI -439 to 4294). CONCLUSIONS: This comprehensive meta-analysis provides an updated global prevalence rate of AK of 14%, indicating a significant worldwide disease burden. The incidence rate of AK was found to be 1928 per 100 000 PY, emphasizing a growing public health concern. However, high heterogeneity among studies suggests that various factors influence the AK prevalence rate, necessitating further research to understand the observed differences.

Do Large Language Model Chatbots perform better than established patient information resources in answering patient questions? A comparative study on melanoma.

BACKGROUND: Large Language Models (LLMs) have a potential role in providing adequate patient information. OBJECTIVES: To compare the quality of LLMs' responses with established Dutch patient information resources (PIRs) in answering patient questions regarding melanoma. METHODS: Responses from ChatGPT versions 3.5 and 4.0, Gemini, and three leading Dutch melanoma PIRs to 50 melanoma-specific questions were examined at baseline and for LLMs again after eight months. Outcomes included (medical) accuracy, completeness, personalisation, readability, and additionally reproducibility for LLMs. Comparative analyses were performed within LLMs and PIRs using Friedman's ANOVA, and between best-performing LLMs and gold-standard PIR using Wilcoxon Signed Ranks test. RESULTS: Within LLMs, ChatGPT-3.5 demonstrated the highest accuracy (p=0.009). Gemini performed best in completeness (p<0.001), personalisation (p=0.007), and readability (p<0.001). PIRs were consistent in accuracy and completeness, with the general practitioner's website excelling in personalisation (p=0.013) and readability (p<0.001). The best-performing LLMs outperformed the gold-standard PIR on all criteria except accuracy. Over time, response reproducibility decreased for all LLMs, showing variability across outcomes. CONCLUSIONS: Although LLMs show potential in providing highly personalised and complete responses to patient questions regarding melanoma, improving and safeguarding accuracy, reproducibility and accessibility is crucial before they can replace or complement conventional PIRs.This study compared the quality of responses from Large Language Models (LLMs) with established Dutch patient information resources (PIRs) for melanoma-related patient questions. Results showed LLMs provided highly personalised and complete answers, often surpassing PIRs. However, improving and safeguarding accuracy, reproducibility and accessibility is crucial before they can replace or complement conventional PIRs.

Development and External Validation of a Prediction Model for Patients with Varicose Veins Suitable for Isolated Ambulatory Phlebectomy.

OBJECTIVE: Isolated ambulatory phlebectomy is a potential treatment option for patients with an incompetent great saphenous vein (GSV) or anterior accessory saphenous vein and one or more incompetent tributaries. Being able to determine which patients will most likely benefit from isolated phlebectomy is important. This study aimed to identify predictors for avoidance of secondary axial ablation after isolated phlebectomy and to develop and externally validate a multivariable model for predicting this outcome. METHODS: For model development, data from patients included in the SAPTAP trial were used. The investigated outcome was avoidance of ablation of the saphenous trunk one year after isolated ambulatory phlebectomy. Pre-defined candidate predictors were analysed with multivariable logistic regression. Predictors were selected using Akaike information criterion backward selection. Discriminative ability was assessed by the concordance index. Bootstrapping was used to correct regression coefficients, and the C index for overfitting. The model was externally validated using a population of 94 patients, with an incompetent GSV and one or more incompetent tributaries, who underwent isolated phlebectomy. RESULTS: For model development, 225 patients were used, of whom 167 (74.2%) did not undergo additional ablation of the saphenous trunk one year after isolated phlebectomy. The final model consisted of three predictors for avoidance of axial ablation: tributary length (< 15 cm vs. > 30 cm: odds ratio [OR] 0.09, 95% confidence interval [CI] 0.02 - 0.40; 15 - 30 cm vs. > 30 cm: OR 0.18, 95% CI 0.09 - 0.38); saphenofemoral junction (SFJ) reflux (absent vs. present: OR 2.53, 95% CI 0.81 - 7.87); and diameter of the saphenous trunk (per millimetre change: OR 0.63, 95% CI 0.41 - 0.96). The discriminative ability of the model was moderate (0.72 at internal validation; 0.73 at external validation). CONCLUSION: A model was developed for predicting avoidance of secondary ablation of the saphenous trunk one year after isolated ambulatory phlebectomy, which can be helpful in daily practice to determine the suitable treatment strategy in patients with an incompetent saphenous trunk and one or more incompetent tributaries. Patients having a longer tributary, smaller diameter saphenous trunk, and absence of terminal valve reflux in the SFJ are more likely to benefit from isolated phlebectomy.

Cumulative incidence and timing of subsequent cutaneous squamous cell carcinomas stratified for patients with organ transplantation and hematologic malignancies: A nationwide cohort study.

BACKGROUND: There is lack of nationwide data on the cumulative incidence and timing of subsequent cutaneous squamous cell carcinomas (cSCCs) among patients with a first cSCC. OBJECTIVE: To investigate the cumulative incidence and timing of subsequent cSCCs. METHODS: Patients with a first cSCC in 2007/2008 from the Netherlands Cancer Registry were linked to the Netherlands Pathology Registry for subsequent cSCCs and the Netherlands Organ Transplant Registry. Cumulative incidence function curves were calculated for subsequent cSCCs and stratified for immune status. RESULTS: Among the 12,345 patients, second to sixth cSCC occurred in 4325, 2010, 1138, 739, and 501 patients, with median time intervals of 1.4, 1.2, 0.9, 0.6, and 0.5 years after the previous cSCC, respectively. The cumulative incidence of a subsequent cSCC at 5 years increased from 28% to 67% for the second to sixth cSCC. For solid organ transplant recipients, the cumulative incidences increased from 74% to 92% and from 41% to 64% for patients with hematologic malignancy. LIMITATIONS: Only histopathologically confirmed cSCCs were included. CONCLUSION: The risk of a subsequent cSCC steeply rises with the number of prior cSCCs and immune status, while the time interval decreases. This can support more informed decisions about follow-up management.

The epidemiology of acne vulgaris in a multiethnic adolescent population from Rotterdam, the Netherlands: A cross-sectional study.

BACKGROUND: Although acne is a prevalent multifactorial inflammatory skin condition, few studies were performed in multiethnic populations. OBJECTIVES: To study the prevalence and determinants of acne in a multiethnic study at the start of puberty. METHODS: This cross-sectional study is embedded in Generation R, a population-based prospective study from Rotterdam, the Netherlands. Three-dimensional facial photos at the center visit in 2016-2019 (of ∼13-year-olds) were used to grade acne severity using the Global Evaluation of the Acne Severity (GEA). Analyses were stratified by biological sex and explored through chi-square tests and multivariable ordinal logistic regression. RESULTS: A total of 4561 children (51% girls) with a median age of 13.5 (IQR 13.3-13.6) were included. The visible acne prevalence (GEA 2-5) for girls vs boys was 62% vs 45% and moderate-to-severe acne (GEA 3-5) 14% vs 9%. Higher puberty stages (adjusted odds ratios: 1.38 [1.20-1.59] and 2.16 [1.86-2.51] for girls and boys, respectively) and darker skin colors V and VI (adjusted odds ratios: 1.90 [1.17-3.08] and 2.43 [1.67-3.56]) were associated with more severe acne in both sexes, and being overweight in boys (adjusted odds ratio: 1.58 [1.15-2.17]). LIMITATIONS: Cross-sectional design. CONCLUSIONS: Acne prevalence was high at the age of 13 years and was associated with advanced puberty, darker skin color, and weight status.

Lifetime prevalence and associated factors of itch with skin conditions: atopic dermatitis, psoriasis and dry skin in individuals aged > 50†years.

BACKGROUND: Itch, common in dermatological conditions, is often accompanied by psychological distress and reduced quality of life. However, research on the prevalence and associated factors of itch with skin conditions in general populations is limited. OBJECTIVES: This cross-sectional study aimed to determine the lifetime prevalence of itch with skin conditions and to identify its associated factors in individuals aged > 50 years. METHODS: Participants from the Rotterdam Study, a population-based cohort, were interviewed to assess whether they had ever had an itchy skin condition, defining lifetime itch with skin conditions. Over 20 demographic, lifestyle, dermatological and nondermatological factors were recorded. Multivariable logistic regression analysis explored associations between these factors and itch with skin conditions, reported as odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: In total, 5246 eligible participants were included (age range 51-100 years, median age 67; 56.0% women). The results revealed a -lifetime prevalence of 33.7% for itch with skin conditions. Factors significantly associated with itch were female sex (OR 1.26, 95% CI 1.11-1.43), body mass index (1.02, 1.01-1.03), self-reported atopic dermatitis (4.29, 3.74-4.92), presence of atopic dermatitis (1.97, 1.60-2.43), self--reported psoriasis (2.31, 1.77-3.01), presence of psoriasis (2.11, 1.55-2.87), self-reported dry skin (1.95, 1.73-2.20), self-reported asthma (1.40, 1.08-1.83), renal impairment (1.45, 1.17-1.79), and clinically relevant depressive (1.85, 1.52-2.25) and anxiety symptoms (1.36, 1.11-1.66). CONCLUSIONS: This study reveals a substantial one-third lifetime prevalence of itch with skin conditions in individuals aged > 50 years. Significant associations with diverse lifestyle, demographic, dermatological and, intriguingly, nondermatological factors, including renal impairment, imply additional contributors to induction or persistence of itch in individuals with skin conditions.

Upadacitinib treatment in a real-world difficult-to-treat atopic dermatitis patient cohort.

BACKGROUND: Upadacitinib was the first JAK-1 selective inhibitor registered for the treatment of moderate-to-severe atopic dermatitis (AD). Although efficacy and safety have been shown in clinical trials, real-world data on the use of upadacitinib in patients that have been treated with other immunosuppressants and targeted therapies is limited. OBJECTIVES: To provide real-world evidence on the use of upadacitinib treatment in moderate-to-severe atopic dermatitis. METHODS: In this prospective observational single-centre study, all AD patients treated with upadacitinib treatment in the context of standard care were included between August 2021 and September 2022. Clinical outcome measures and adverse events (AEs) were analysed. RESULTS: Forty-eight patients were included. The majority (n = 39; 81%) had failed (ineffectiveness) on other targeted therapies, including other JAK inhibitors and biologics. Thirty-four (71%) patients were still using upadacitinib treatment at last follow up (median duration 46.5 weeks). Fourteen (29%) patients discontinued treatment due to ineffectiveness or AE. Upadacitinib treatment led to a significant decrease of disease severity during a median follow up of 37.5 weeks. Median IGA at baseline decreased from 3 (IQR 2-3) to 1.5 (IQR 1-2) at last review (p < 0.001). Median NRS itch decreased from 7 (IQR 5-8) at baseline to 2.25 (IQR 0.25-6.5) at last review (p < 0.001). Three patients discontinued treatment due to AE. Forty-eight AEs were reported, including acne-like eruptions (25%), nausea (13%) and respiratory tract infections (10%). CONCLUSIONS: In this real-world cohort, we confirmed that upadacitinib is an effective treatment in a subset of AD patients that have failed several previous systemic immunosuppressive and biologic treatments. Overall, AE were mostly well tolerated and not a reason to discontinue treatment for most patients.