{"title":"Real-World Maintenance of Remission in Atopic Dermatitis Patients With Upadacitinib: A Multicenter Retrospective Study in Japan (ROADMAP Study)","authors":"Yuichiro Tsunemi, Atsuyuki Igarashi, Takeshi Ishido, Hidehisa Saeki","doi":"10.1111/1346-8138.70299","DOIUrl":"10.1111/1346-8138.70299","url":null,"abstract":"<p>Upadacitinib (UPA) is a selective Janus kinase 1 inhibitor that improves moderate-to-severe atopic dermatitis, but real-world strategies to maintain remission after response remain unclear. We conducted a multicenter retrospective study in Japan of 219 patients aged ≥ 12 years who achieved protocol-defined remission, defined as Investigator's Global Assessment (IGA) 0/1 at two visits ≥ 4 weeks apart during UPA treatment. Patients were classified as on-label (continuous daily 15 or 30 mg), spacing/reduction (extension of the dosing interval and/or dose-reduction after remission), or discontinuation (stopping UPA after remission). The primary endpoint was maintenance of remission over 48 weeks; secondary endpoints were time to relapse, outcomes after treatment modification, remission at 72 weeks after ≥ 24 weeks of sustained remission, and safety. Because the analysis was restricted to responders who achieved remission, generalizability to all UPA-treated patients is limited. Seventy-five percent of patients achieved IGA 0/1 within about 4 months of starting UPA. Over the subsequent 48 weeks, 127/200 (63.5%, 95% CI 56.6–69.9) maintained IGA 0/1. When stratified by post-remission dosing strategy (<i>n</i> = 193; excluding 7 who switched to other systemic therapy), remission at 48 weeks was maintained in 93/145 (64.1%, 95% CI 55.8–71.9) in the on-label group, 24/32 (75.0%, 95% CI 56.6–88.5) in the spacing/reduction group, and 6/16 (37.5%, 95% CI 15.2–64.6) in the discontinuation group. Among patients with ≥ 24 weeks of sustained remission, week-72 IGA 0/1 maintenance rates were 70.7% (95% CI 60.7–79.1; <i>n</i> = 107), 100% (95% CI 63.1–100.0; <i>n</i> = 8), and 60.0% (95% CI 20.0–90.0; <i>n</i> = 5) in the on-label, spacing/reduction, and discontinuation groups, respectively; estimates for spacing/reduction and discontinuation were imprecise due to small sample sizes. Longer on-label treatment before tapering or discontinuation tended to be associated with a lower relapse risk. UPA showed a safety profile consistent with previous studies. Acne, herpes simplex, herpes zoster, and folliculitis were the most frequent adverse events, and most were mild and manageable, although one herpes zoster case required temporary interruption. In this responder-enriched real-world Japanese cohort, UPA induced remission in most patients within 4 months and allowed approximately two-thirds to maintain remission over 48 weeks. Observed outcomes suggest that maintaining on-label dosing and cautious spacing/reduction after sustained remission may help preserve disease control, whereas discontinuation may be associated with a higher risk of relapse; however, comparisons between dosing strategies are descriptive and hypothesis-generating. Prospective studies are needed to confirm these findings.</p>","PeriodicalId":54848,"journal":{"name":"Journal of Dermatology","volume":"53 7","pages":"980-989"},"PeriodicalIF":2.3,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1346-8138.70299","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148166429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Journal of DermatologyPub Date : 2026-07-07Epub Date: 2026-05-04DOI: 10.1111/1346-8138.70303
Ken Horisaki, Keisuke Goto, Arata Tsutsumida, Tsubasa Hiraki, Shusuke Yoshikawa
{"title":"Melanoma Dissemination Through Bullous Solar Elastosis: Previously Undescribed Pattern of Cancer Dissemination","authors":"Ken Horisaki, Keisuke Goto, Arata Tsutsumida, Tsubasa Hiraki, Shusuke Yoshikawa","doi":"10.1111/1346-8138.70303","DOIUrl":"10.1111/1346-8138.70303","url":null,"abstract":"<div>\u0000 \u0000 <p>Metastasis can be classified into three forms based on the route of spread: lymphatic, hematogenous, and seeding within body cavities. We report a case of melanoma exhibiting seeding/dissemination around the primary site through bullous solar elastosis, a previously unreported pattern. A 75-year-old man presented with a black nodule on the right forearm. One year after excision, a bluish-gray macular lesion developed distal to the surgical scar. Histopathology of the primary lesion revealed features of high-CSD melanoma with bullous solar elastosis forming cleft-like spaces in the superficial and mid-dermis, containing scattered melanoma cells. The recurrent lesion demonstrated a widespread band-like distribution of melanoma cells along bullous solar elastosis. This case suggests that cleft-like spaces in bullous solar elastosis may act as conduits for horizontal tumor spread, resulting in clinicopathological features that are distinct from conventional metastasis. Recognition of this pathway may improve diagnostic accuracy and understanding of cancer behavior in chronically sun-exposed skin.</p>\u0000 </div>","PeriodicalId":54848,"journal":{"name":"Journal of Dermatology","volume":"53 7","pages":"1062-1066"},"PeriodicalIF":2.3,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147848302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Journal of DermatologyPub Date : 2026-07-07Epub Date: 2026-05-11DOI: 10.1111/1346-8138.70306
Ayano Maruyama, Ayaka Sotozono, Takeshi Fukumoto
{"title":"Acquired Idiopathic Generalized Anhidrosis as a Late-Onset Immune-Related Adverse Event of Pembrolizumab in a Patient With Lung Adenocarcinoma: A Case Report and Review of the Literature","authors":"Ayano Maruyama, Ayaka Sotozono, Takeshi Fukumoto","doi":"10.1111/1346-8138.70306","DOIUrl":"10.1111/1346-8138.70306","url":null,"abstract":"<div>\u0000 \u0000 <p>Acquired idiopathic generalized anhidrosis (AIGA) is a rare disorder of sweating that can be life-threatening owing to the risk of heat stroke. AIGA as an immune-related adverse event (irAE) of immune checkpoint inhibitors (ICIs) has been reported in only three cases. We report a 69-year-old man with unresectable lung adenocarcinoma (cT1N2M1b, Stage 4A) with hepatic metastasis who developed generalized anhidrosis after approximately 2 years (30 cycles) of pembrolizumab monotherapy. EGFR, ALK, and ROS1 were negative, and programmed death-ligand 1 (PD-L1) tumor proportion score (TPS; 22C3 antibody) was 90%–100%. Sweat testing revealed anhidrosis exceeding 75% of the body surface. Acetylcholine injection testing indicated idiopathic pure sudomotor failure (IPSF)-type dysfunction. Skin biopsy revealed site-dependent findings: peri-eccrine lymphocytic infiltration involving the sweat glands and ducts in the sweating area (axilla) and prominent peri-eccrine fibrosis in the anhidrotic area (left forearm). Serum carcinoembryonic antigen (CEA) was elevated to 16.7 ng/mL without tumor progression, prompting diagnostic workup including colonoscopy, which revealed no abnormalities. The patient was treated with three courses of methylprednisolone pulse therapy (1000 mg/day × 3 days) over 7 months and fexofenadine, resulting in partial sweating recovery and CEA decline to 3.0 ng/mL. Pembrolizumab was continued throughout without interruption, and the patient maintained durable stable disease (SD) over approximately 45 months (alive at last follow-up). This case demonstrates the histopathological spectrum of ICI-induced AIGA from inflammation to fibrosis within a single patient, and highlights CEA elevation as both a diagnostic clue and a potential pitfall in oncological practice.</p>\u0000 </div>","PeriodicalId":54848,"journal":{"name":"Journal of Dermatology","volume":"53 7","pages":"1072-1076"},"PeriodicalIF":2.3,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147871108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Pustular Mycosis Fungoides Triggered by Systemic Interferon-γ","authors":"Mai Nishida, Takatoshi Shimauchi, Yuto Ishikawa, Yasuaki Ogura, Kazuo Kurihara, Reiko Kageyama, Kazumitsu Sugiura, Tetsuya Honda","doi":"10.1111/1346-8138.70278","DOIUrl":"10.1111/1346-8138.70278","url":null,"abstract":"<div>\u0000 \u0000 <p>Pustular mycosis fungoides (pMF) is a rare variant of MF characterized by the clinical and histopathological formation of pustules. We report a 71-year-old Japanese woman with established MF who developed a generalized pustular eruption temporally triggered by systemic interferon (IFN)-γ administration. Clinically, the patient presented with generalized erythema with coalescing pustules mimicking generalized pustular psoriasis or acute generalized exanthematous pustulosis. Histological examination revealed the simultaneous presence of spongiform pustules of Kogoj and large transformed CD30<sup>+</sup> atypical lymphoid cells. The pustules resolved rapidly upon the discontinuation of IFN-γ and the administration of systemic antibiotics. Cytokine analysis at the onset of pustulosis revealed marked elevations in serum IL-8, IL-18, IL-23, and IL-6 compared with healthy controls; these levels normalized during remission. This case suggests that systemic IFN-γ can act as a trigger for pMF. Furthermore, the distinct cytokine profile highlights that the IL-23/IL-17/IL-8 axis may be a crucial mediator in the pathogenesis of pMF.</p>\u0000 </div>","PeriodicalId":54848,"journal":{"name":"Journal of Dermatology","volume":"53 7","pages":"1032-1035"},"PeriodicalIF":2.3,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147725159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Journal of DermatologyPub Date : 2026-07-07Epub Date: 2026-04-29DOI: 10.1111/1346-8138.70297
Miwa Ashida, Takeshi Nakahara, Hiroyuki Murota
{"title":"Persistent Blood Dioxins and Sensory Impairment Assessed by Quantitative Sensory Testing in 115 Yusho Patients 57 Years After Exposure","authors":"Miwa Ashida, Takeshi Nakahara, Hiroyuki Murota","doi":"10.1111/1346-8138.70297","DOIUrl":"10.1111/1346-8138.70297","url":null,"abstract":"<div>\u0000 \u0000 <p>Yusho patients continue to experience sensory symptoms such as pruritus and numbness even decades after dioxin exposure. However, objective assessment of long-term sensory impairment remains limited. Using a minimally invasive quantitative sensory assessment method, we conducted an exploratory investigation into the relationship between sensory thresholds and dioxin exposure in Yusho patients. Minimum perceived current (MPC) values were modestly higher in Yusho patients than in controls. Patients with pruritus or numbness tended to show lower MPC values than those without these symptoms, although correlations between MPC and pruritus and numbness visual analog scale (VAS) were not consistently observed. Although a weak positive correlation was observed between MPC and PCDF levels and a similar trend was noted in the categorical comparison, this association was attenuated after adjustment for age and sex. Importantly, the high-exposure group included a significantly greater proportion of women, who typically exhibit lower MPC values. These findings are consistent with persistent sensory impairment that cannot be fully explained by exposure intensity. This study provides valuable insight into the long-term health effects of chronic dioxin exposure.</p>\u0000 </div>","PeriodicalId":54848,"journal":{"name":"Journal of Dermatology","volume":"53 7","pages":"1053-1056"},"PeriodicalIF":2.3,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147793769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Journal of DermatologyPub Date : 2026-06-02Epub Date: 2026-05-03DOI: 10.1111/1346-8138.70247
Aya Yamamoto, Yuki Enomoto, Mai Sakurai, Oki Watanabe, Yoshifumi Kanayama, Yumi Koike, Takashi Sakaida, Akimichi Morita
{"title":"Efficacy of Minimal Blistering Dose-Based Versus Conventional Excimer Laser Therapy for Vitiligo","authors":"Aya Yamamoto, Yuki Enomoto, Mai Sakurai, Oki Watanabe, Yoshifumi Kanayama, Yumi Koike, Takashi Sakaida, Akimichi Morita","doi":"10.1111/1346-8138.70247","DOIUrl":"10.1111/1346-8138.70247","url":null,"abstract":"<p>Excimer laser therapy is an established treatment for vitiligo, but the optimal irradiation protocol remains unclear. Irradiation based on the minimal blistering dose (MBD) was recently proposed, but its efficacy relative to conventional protocols has not been systematically evaluated. In this study, we retrospectively analyzed 43 patients with vitiligo who underwent more than 20 sessions of excimer laser therapy at Nagoya City University Hospital, including 29 treated with the conventional protocol and 14 with the MBD protocol. In the conventional group, treatment was initiated at half the minimal erythema dose (MED) and gradually increased, whereas in the MBD group, treatment was initiated at twice the MED and maintained at the MBD, with further increases after photohardening. Treatment efficacy was assessed using the Vitiligo Area Scoring Index (VASI) at baseline, and after the 10th and 20th irradiation sessions. The MBD group showed significantly greater improvement in VASI (%) compared with the 1/2 MED group (<i>p</i> = 0.0041). The area under the curve (AUC<sub>₀–₂₀</sub>) for ΔVASI% over 20 sessions was also significantly higher in the MBD group (<i>p</i> < 0.0001). Furthermore, Kaplan–Meier analysis of time to VASI 50 achievement demonstrated that patients in the MBD group reached VASI 50 significantly earlier than those in the 1/2 MED group. Adverse events, including erythema, burning, and blistering, were mild and transient and resolved without treatment discontinuation. In conclusion, MBD-based excimer laser irradiation achieved earlier repigmentation with fewer sessions compared with the conventional protocol without a statistically significant increase in cumulative irradiation dose. This approach may reduce the treatment burden and accelerate clinical improvement in patients with vitiligo.</p>","PeriodicalId":54848,"journal":{"name":"Journal of Dermatology","volume":"53 6","pages":"925-929"},"PeriodicalIF":2.7,"publicationDate":"2026-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1346-8138.70247","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147825247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Immunohistochemistry Revealed Distinct IL-36γ Localization Among Different Skin Diseases","authors":"Megumi Kishimoto, Miho Kimura-Sashikawa, Mayumi Komine","doi":"10.1111/1346-8138.70291","DOIUrl":"10.1111/1346-8138.70291","url":null,"abstract":"<div>\u0000 \u0000 <p>IL-36γ is highly expressed in psoriatic skin lesions and promotes neutrophil infiltration through the induction of neutrophil chemotactic chemokines. While IL-36γ has been established to play an important role in the pathogenesis of psoriasis, its localization in the psoriatic epidermis has not been fully elucidated, and the difference in its expression patterns among other inflammatory skin diseases remains unclear. We investigated IL-36γ localization using immunohistochemistry in skin specimens from patients with psoriasis vulgaris (<i>n</i> = 36), generalized pustular psoriasis (<i>n</i> = 11), pyoderma gangrenosum (<i>n</i> = 6), palmoplantar pustulosis (<i>n</i> = 6), tumor necrosis factor inhibitor-induced paradoxical reaction (<i>n</i> = 3), pustular drug eruption (<i>n</i> = 5), atopic dermatitis (<i>n</i> = 11), tinea infection (<i>n</i> = 3), and mycosis fungoides (<i>n</i> = 9), as well as uninvolved skin adjacent to benign tumors (<i>n</i> = 4). Staining scores were assessed based on intensity and distribution, and nuclear positivity was compared among diseases. IL-36γ was strongly expressed in the upper epidermis of psoriasis vulgaris and generalized pustular psoriasis, with staining scores significantly higher than those in atopic dermatitis and adjacent normal skin. Expression in pyoderma gangrenosum, palmoplantar pustulosis, paradoxical reaction, and pustular drug eruption was comparable to psoriasis vulgaris. Nuclear staining of IL-36γ was frequent in psoriasis vulgaris (33/36, 92%) and generalized pustular psoriasis (11/11, 100%), but absent in pyoderma gangrenosum. The difference in nuclear positivity between psoriasis and pyoderma gangrenosum was statistically significant. These findings confirm that IL-36γ is highly expressed in psoriatic lesions but is not specific to psoriasis, as it is also upregulated in other inflammatory skin diseases. Nuclear staining was observed in psoriasis but not in pyoderma gangrenosum, suggesting a potential disease-specific localization pattern. The biological significance and mechanism of nuclear localization remain unclear, as the IL-36γ molecule lacks a nuclear localization signal. Our findings highlight that the localization of IL-36γ differs among inflammatory skin diseases, suggesting that it may reflect pathogenic differences and warrant further investigation.</p>\u0000 </div>","PeriodicalId":54848,"journal":{"name":"Journal of Dermatology","volume":"53 6","pages":"934-938"},"PeriodicalIF":2.7,"publicationDate":"2026-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147825354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Journal of DermatologyPub Date : 2026-06-02Epub Date: 2026-04-10DOI: 10.1111/1346-8138.70252
Yunran Peng, Yang Guan, Kunlun Lv, Chao Yang, Quan Chen, Huijun Wang, Zhimiao Lin
{"title":"Mutation Analysis in Ten Cases With PNPLA1-Nonsyndromic Epidermal Differentiation Disorder: Evidence of a Founder Effect","authors":"Yunran Peng, Yang Guan, Kunlun Lv, Chao Yang, Quan Chen, Huijun Wang, Zhimiao Lin","doi":"10.1111/1346-8138.70252","DOIUrl":"10.1111/1346-8138.70252","url":null,"abstract":"<div>\u0000 \u0000 <p>Autosomal recessive congenital ichthyosis (ARCI) belongs to a heterogeneous group of nonsyndromic epidermal differentiation disorders (nEDD). Variants in <i>PNPLA1</i>, which encodes a transacylase essential for the formation of epidermal lipid barrier, underlie ARCI10. This study aims to unveil the underlying genetic basis in ten Chinese cases diagnosed with ARCI, and to determine the origin of a prevalent variant. Ten cases, encompassing twelve patients with ARCI, were recruited for this study. Whole-exome sequencing combined with Sanger sequencing was used to detect the underlying variants. Haplotype analysis using flanking highly polymorphic SNPs was used to trace the origin of the c.1300delG variant in the <i>PNPLA1</i> gene. All patients developed generalized fine scales and erythema shortly after birth. Marked phenotypic heterogeneity was observed among the affected individuals, leading to diagnosis of either generalized or localized nEDD. In total, we detected three recurrent variants (c.1300delG, p.A434Hfs*22; c.434 T > C, p.Ile145Thr; c.488C > T, p.Pro163Leu) and five novel variants (c.205 + 1G > A, splicing; c.74C > T, p.Ser25Phe; c.473G > A, p.Cys158Tyr; c.731A > G, p.Tyr244Cys; c.1318C > T, p.Arg440*) in <i>PNPLA1</i>. The c.1300delG variant, prevalent in 7 unrelated ARCI cases, was associated with a common haplotype. Furthermore, we presented the beneficial effect of secukinumab treatment in one of our patients. Our findings suggest that the c.1300delG variant is a highly prevalent variant in Chinese <i>PNPLA1</i>-associated nEDD patients, and indicate that the recurrent variant may originate from a common ancestor in southern China, suggesting a regional founder effect. The observed response with secukinumab in one patient suggests that it might represent a potential therapeutic option for <i>PNPLA1</i>-nEDD patients.</p>\u0000 </div>","PeriodicalId":54848,"journal":{"name":"Journal of Dermatology","volume":"53 6","pages":"896-904"},"PeriodicalIF":2.7,"publicationDate":"2026-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147655611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Journal of DermatologyPub Date : 2026-06-02Epub Date: 2026-04-28DOI: 10.1111/1346-8138.70283
Bo Ri Kim, Jihee Nam, Jin Lee, Suna Kang, Sung-Won Kang, Minsu Kim, Juhee Cho, Danbee Kang, Sang Woong Youn
{"title":"Long-Term Particulate Matter Exposure and Risk of Psoriasis Incidence, and Short-Term Exposure and Risk of Exacerbation: A Nationwide Cohort Study","authors":"Bo Ri Kim, Jihee Nam, Jin Lee, Suna Kang, Sung-Won Kang, Minsu Kim, Juhee Cho, Danbee Kang, Sang Woong Youn","doi":"10.1111/1346-8138.70283","DOIUrl":"10.1111/1346-8138.70283","url":null,"abstract":"<div>\u0000 \u0000 <p>Psoriasis is a chronic inflammatory skin disease influenced by environmental factors, including air pollution. However, large-scale evidence from Asian populations, where particulate matter (PM) exposure is relatively high, remains limited. This study aimed to evaluate the association between long-term PM exposure and psoriasis incidence, and short-term exposure with exacerbation risk. We conducted a cohort study using the Korean National Health Insurance Service database, involving 8 396 764 individuals. Long-term exposure was assessed based on annual average concentrations of fine PM (PM<sub>2.5</sub>) and coarse PM (PM<sub>10</sub>), while short-term exposure was measured using daily PM levels matched with control days. Long-term exposure to PM<sub>2.5</sub> and PM<sub>10</sub> was associated with a 19% and 27% higher risk of incident psoriasis (adjusted HR 1.19 and 1.27; 95% CI 1.16–1.22 and 1.25–1.30). Short-term exposure was linked to an increased risk of psoriasis exacerbation (adjusted OR 1.03 for PM<sub>2.5</sub>, 95% CI 1.00–1.06; adjusted OR 1.01 for PM<sub>10</sub>, 95% CI 1.00–1.03). Stronger associations were observed in younger individuals, urban residents, those with lower socioeconomic status, ever-smokers, and patients with comorbid allergic diseases. These findings suggest that both long-term and short-term PM exposure contribute to psoriasis onset and exacerbation, underscoring air pollution as an important modifiable risk factor in psoriasis development and control.</p>\u0000 </div>","PeriodicalId":54848,"journal":{"name":"Journal of Dermatology","volume":"53 6","pages":"905-913"},"PeriodicalIF":2.7,"publicationDate":"2026-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147793792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}