{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T11:10:38Z","timestamp":1788952238865,"version":"build-2803163510"},"reference-count":52,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T00:00:00Z","timestamp":1788912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Public Health"],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>\n                      Psoriasis, a chronic inflammatory skin disorder, is closely linked to environmental triggers. However, the combined effects of extreme cold and nitrogen dioxide (NO\n                      <jats:sub>2<\/jats:sub>\n                      ), two common environmental factors, on psoriasis patients remain unclear. This study aims to explore the associations of co-exposures to extreme cold and NO\n                      <jats:sub>2<\/jats:sub>\n                      with psoriasis outpatient visits and systemic inflammatory markers among patients with complete blood count (CBC).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Data from patients with psoriasis were collected in a subtropical megacity of China between January 2021 and December 2025. A distributed lag non-linear model (DLNM) was used to evaluate the outpatient visit risk associated with extreme cold, extreme NO\n                      <jats:sub>2<\/jats:sub>\n                      , and their co-exposure, identifying susceptible subgroups. Additive interaction was assessed using an interaction term and the relative excess risk due to interaction (RERI). Furthermore, to evaluate the effect of co-exposure on systemic inflammatory markers, a sub-cohort of patients with CBC records was extracted for exploratory analysis.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      A total of 63,411 psoriasis outpatient visits and 3,048 patients who underwent CBC tests were recorded during the cold seasons of 2021\u20132025. Co-exposure to extreme cold and NO\n                      <jats:sub>2<\/jats:sub>\n                      was associated with an increased risk of psoriasis outpatient visits at Lag14 (RR\u202f=\u202f1.017, 95% CI: 1.004\u20131.030), with a higher point estimate compared to single-factor exposure; however, the interaction test was not significant (RERI\u202f=\u202f0.026, 95% CI: \u22120.055 to 0.108). Stratified analysis revealed that the association between co-exposure and outpatient visits varied by age, with a stronger effect observed in younger age groups (Q-test for interaction,\n                      <jats:italic>p<\/jats:italic>\n                      =\u202f0.004). In exploratory analyses, SII showed a significant global association (\n                      <jats:italic>p<\/jats:italic>\n                      =\u202f0.016) at Lag7 (OR\u202f=\u202f1.109, 95% CI: 1.031\u20131.194), whereas NLR and PLR were not significant.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      Co\n                      <jats:bold>-<\/jats:bold>\n                      exposure to extreme cold and NO\n                      <jats:sub>2<\/jats:sub>\n                      is associated with an increased risk of psoriasis outpatient visits, particularly in susceptible age groups, although no synergistic effect was detected between the two exposures. Exploratory analyses also suggest a potential association with elevated systemic inflammation, warranting further investigation. These findings provide preliminary evidence for the role of combined environmental exposures in psoriasis and highlight the importance of considering age-specific vulnerability when developing targeted public health interventions for at-risk populations.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fpubh.2026.1916342","type":"journal-article","created":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T10:17:24Z","timestamp":1788949044000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Association of co-exposure to extreme cold and nitrogen dioxide with psoriasis outpatient visits and systemic inflammation"],"prefix":"10.3389","volume":"14","author":[{"given":"Yuting","family":"Huang","sequence":"first","affiliation":[{"name":"School of Nursing, Nanjing Medical University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suo","family":"Mo","sequence":"additional","affiliation":[{"name":"Department of Laboratory, Hospital for Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bokun","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Network Information Center, Hospital for Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haili","family":"Ren","sequence":"additional","affiliation":[{"name":"School of Nursing, Nanjing Medical University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yajuan","family":"Zuo","sequence":"additional","affiliation":[{"name":"Department of Laboratory, Hospital for Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuxiao","family":"Zhou","sequence":"additional","affiliation":[{"name":"Department of Laboratory, Hospital for Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Laboratory, Hospital for Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuemei","family":"Zhou","sequence":"additional","affiliation":[{"name":"The Fourth Clinical College, Nanjing Medical University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiemiao","family":"Shen","sequence":"additional","affiliation":[{"name":"School of Nursing, Nanjing Medical University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Minghui","family":"Ji","sequence":"additional","affiliation":[{"name":"School of Nursing, Nanjing Medical University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xianfeng","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Laboratory, Hospital for Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,9]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"1945","DOI":"10.1001\/jama.2020.4006","article-title":"Pathophysiology, clinical presentation, and treatment of psoriasis: a review","volume":"323","author":"Armstrong","year":"2020","journal-title":"JAMA"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"45","DOI":"10.1038\/s41572-025-00630-5","article-title":"The Psoriasis","volume":"11","author":"Armstrong","year":"2025","journal-title":"Nat Rev Dis Primers"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"314","DOI":"10.1097\/cm9.0000000000003636","article-title":"Regional and local burden of psoriasis in China, 1990-2021: findings from the global burden of disease study 2021","volume":"139","author":"Yang","year":"1990","journal-title":"Chin Med J"},{"key":"ref4","doi-asserted-by":"publisher","first-page":"425","DOI":"10.1016\/j.ad.2020.11.017","article-title":"Burden of psoriasis in Catalonia: epidemiology, associated comorbidities, health care utilization, and sick leave","volume":"112","author":"Puig","year":"2021","journal-title":"Actas Dermosifiliogr (Engl Ed)"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"1034","DOI":"10.1016\/j.jid.2025.08.038","article-title":"Global burden of psoriasis from 1990 to 2021 and potential factors: a systematic analysis","volume":"146","author":"Wei","year":"2026","journal-title":"J Invest Dermatol"},{"key":"ref6","doi-asserted-by":"publisher","first-page":"108","DOI":"10.1186\/s12964-023-01381-0","article-title":"Triggers for the onset and recurrence of psoriasis: a review and update","volume":"22","author":"Liu","year":"2024","journal-title":"Cell Commun Signal"},{"key":"ref7","doi-asserted-by":"publisher","first-page":"e2421665","DOI":"10.1001\/jamanetworkopen.2024.21665","article-title":"Exposure to air pollution, genetic susceptibility, and psoriasis risk in the UK","volume":"7","author":"Wu","year":"2024","journal-title":"JAMA Netw Open"},{"key":"ref8","doi-asserted-by":"publisher","first-page":"420","DOI":"10.1093\/bjd\/ljae391","article-title":"Joint exposure to multiple air pollutants, genetic risk and incident psoriasis: a large-scale prospective cohort study","volume":"192","author":"Xiong","year":"2025","journal-title":"Br J Dermatol"},{"key":"ref9","year":"2021"},{"key":"ref10","doi-asserted-by":"publisher","first-page":"523","DOI":"10.1164\/rccm.201904-0834ED","article-title":"Traffic-related air pollution, health, and allergy: the role of nitrogen dioxide","volume":"200","author":"Bosson","year":"2019","journal-title":"Am J Respir Crit Care Med"},{"key":"ref11","doi-asserted-by":"publisher","first-page":"2601","DOI":"10.1007\/s00484-025-02977-6","article-title":"Association between short-term air pollutants and psoriasis outpatient visits: a time series study in Nanchang, China","volume":"69","author":"Qu","year":"2025","journal-title":"Int J Biometeorol"},{"key":"ref12","doi-asserted-by":"publisher","first-page":"1071263","DOI":"10.3389\/fpubh.2022.1071263","article-title":"Short-term effects of air pollutants on outpatients with psoriasis in a Chinese city with a subtropical monsoon climate","volume":"10","author":"Wang","year":"2022","journal-title":"Front Public Health"},{"key":"ref13","doi-asserted-by":"publisher","first-page":"491","DOI":"10.1093\/bjd\/ljac124","article-title":"Effects of ambient air pollution on outpatient visits for psoriasis in Wuhan, China: a time-series analysis","volume":"188","author":"Lan","year":"2023","journal-title":"Br J Dermatol"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"713","DOI":"10.1016\/j.anai.2023.08.007","article-title":"The impact of temperature on the skin barrier and atopic dermatitis","volume":"131","author":"Hui-Beckman","year":"2023","journal-title":"Ann Allergy Asthma Immunol"},{"key":"ref15","doi-asserted-by":"publisher","first-page":"e70078","DOI":"10.1111\/exd.70078","article-title":"The impacts of seasonal factors on psoriasis","volume":"34","author":"Yang","year":"2025","journal-title":"Exp Dermatol"},{"key":"ref16","doi-asserted-by":"publisher","first-page":"723","DOI":"10.1186\/s12951-024-03009-y","article-title":"Mechanism of cold exposure delaying wound healing in mice","volume":"22","author":"Li","year":"2024","journal-title":"J Nanobiotechnol"},{"key":"ref17","doi-asserted-by":"publisher","first-page":"116536","DOI":"10.1016\/j.jenvman.2022.116536","article-title":"The diminishing effects of winter heating on air quality in northern China","volume":"325","author":"Wang","year":"2023","journal-title":"J Environ Manag"},{"key":"ref18","doi-asserted-by":"publisher","first-page":"nwab061","DOI":"10.1093\/nsr\/nwab061","article-title":"Untangling the contributions of meteorological conditions and human mobility to tropospheric NO(2) in Chinese mainland during the COVID-19 pandemic in early 2020","volume":"8","author":"Zhang","year":"2021","journal-title":"Natl Sci Rev"},{"key":"ref19","doi-asserted-by":"publisher","first-page":"1117","DOI":"10.1164\/rccm.202204-0657OC","article-title":"The effects of coexposure to extremes of heat and particulate air pollution on mortality in California: implications for climate change","volume":"206","author":"Rahman","year":"2022","journal-title":"Am J Respir Crit Care Med"},{"key":"ref20","doi-asserted-by":"publisher","first-page":"74","DOI":"10.1186\/s12940-025-01234-y","article-title":"Exposure to consecutive extreme ozone-heatwave events and neurological disorders: a retrospective cohort study in Nanjing, China","volume":"24","author":"Ren","year":"2025","journal-title":"Environ Health"},{"key":"ref21","doi-asserted-by":"publisher","first-page":"1043380","DOI":"10.3389\/fimmu.2023.1043380","article-title":"Exploring the association and causal effect between white blood cells and psoriasis using large-scale population data","volume":"14","author":"Zhou","year":"2023","journal-title":"Front Immunol"},{"key":"ref22","doi-asserted-by":"publisher","first-page":"228","DOI":"10.1007\/s00403-024-02994-2","article-title":"Associations of novel complete blood count-derived inflammatory markers with psoriasis: a systematic review and meta-analysis","volume":"316","author":"Liu","year":"2024","journal-title":"Arch Dermatol Res"},{"key":"ref23","doi-asserted-by":"publisher","first-page":"3868","DOI":"10.3390\/ijms26083868","article-title":"The relationship between neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and systemic immune-inflammation index markers and response to biological therapy in patients with psoriasis","volume":"26","author":"Kimak-Pielas","year":"2025","journal-title":"Int J Mol Sci"},{"key":"ref24","doi-asserted-by":"publisher","first-page":"3992","DOI":"10.3390\/jcm13143992","article-title":"Blood-count-derived inflammatory markers as predictors of response to biologics and small-molecule inhibitors in psoriasis: a multicenter study","volume":"13","author":"Morariu","year":"2024","journal-title":"J Clin Med"},{"key":"ref25","doi-asserted-by":"publisher","first-page":"334","DOI":"10.1001\/jamadermatol.2023.5895","article-title":"Prevalence of pretreatment testing recommended for patients with chronic inflammatory skin diseases","volume":"160","author":"Schneeweiss","year":"2024","journal-title":"JAMA Dermatol"},{"key":"ref26","doi-asserted-by":"publisher","first-page":"101","DOI":"10.1016\/j.jes.2021.10.022","article-title":"Short-term impacts of air pollution on the platelet-lymphocyte ratio and neutrophil-lymphocyte ratio among urban adults in China","volume":"125","author":"Qiu","year":"2023","journal-title":"J Environ Sci (China)"},{"key":"ref27","doi-asserted-by":"publisher","first-page":"1702","DOI":"10.1186\/s12889-024-19116-2","article-title":"Short-term exposure to air pollution on peripheral white blood cells and inflammation biomarkers: a cross-sectional study on rural residents","volume":"24","author":"Yang","year":"2024","journal-title":"BMC Public Health"},{"key":"ref28","doi-asserted-by":"publisher","first-page":"114214","DOI":"10.1016\/j.ijheh.2023.114214","article-title":"Ambient temperature exposure causes lung function impairment: the evidence from controlled temperature study in healthy subjects (CTSHS)","volume":"252","author":"Qiu","year":"2023","journal-title":"Int J Hyg Environ Health"},{"key":"ref29","doi-asserted-by":"publisher","first-page":"5443","DOI":"10.13227\/j.hjkx.202210203","article-title":"Effect of carbon dioxide emission reduction policy on air quality improvement in Jiangsu Province","volume":"44","author":"Wang","year":"2023","journal-title":"Huan Jing Ke Xue"},{"key":"ref30","doi-asserted-by":"publisher","first-page":"35","DOI":"10.1161\/circulationaha.122.061832","article-title":"Associations between extreme temperatures and cardiovascular cause-specific mortality: results from 27 countries","volume":"147","author":"Alahmad","year":"2023","journal-title":"Circulation"},{"key":"ref31","doi-asserted-by":"publisher","first-page":"8","DOI":"10.4103\/tjem.tjem_198_23","article-title":"Unraveling the clinical significance and prognostic value of the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, systemic immune-inflammation index, systemic inflammation response index, and delta neutrophil index: an extensive literature review","volume":"24","author":"Islam","year":"2024","journal-title":"Turk J Emerg Med"},{"key":"ref32","doi-asserted-by":"publisher","first-page":"220095","DOI":"10.1183\/16000617.0095-2022","article-title":"Clinical significance of the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio in acute exacerbations of COPD: present and future","volume":"31","author":"Zinellu","year":"2022","journal-title":"Eur Respir Rev"},{"key":"ref33","doi-asserted-by":"publisher","first-page":"1","DOI":"10.18637\/jss.v043.i08","article-title":"Distributed lag linear and non-linear models in R: the package dlnm","volume":"43","author":"Gasparrini","year":"2011","journal-title":"J Stat Softw"},{"key":"ref34","doi-asserted-by":"publisher","first-page":"109364","DOI":"10.1016\/j.envint.2025.109364","article-title":"Mortality risk and burden attributable to compound cold extreme in China: a national time series study","volume":"197","author":"Jiang","year":"2025","journal-title":"Environ Int"},{"key":"ref35","doi-asserted-by":"publisher","first-page":"101194","DOI":"10.1016\/j.resplu.2025.101194","article-title":"Influence of extreme temperatures on out-of-hospital cardiac arrest cases in Hungary: a national time-series analysis","volume":"27","author":"Nagy","year":"2026","journal-title":"Resusc Plus"},{"key":"ref36","doi-asserted-by":"publisher","first-page":"465","DOI":"10.3390\/land13040465","article-title":"Using GAMs to explore the influence factors and their interactions on land surface temperature: a case study in Nanjing","volume":"13","author":"Zhang","year":"2024","journal-title":"Land (Basel)"},{"key":"ref37","doi-asserted-by":"publisher","first-page":"e20974","DOI":"10.7717\/peerj.20974","article-title":"Role of dendritic cells and B cells in the skin of imiquimod (IMQ)-induced psoriasis-like mouse model","volume":"14","author":"Noor","year":"2026","journal-title":"PeerJ"},{"key":"ref38","doi-asserted-by":"publisher","first-page":"1641225","DOI":"10.3389\/fimmu.2025.1641225","article-title":"Impact of temperature trend-defined seasonality on psoriasis treatment outcomes: a multicenter longitudinal study","volume":"16","author":"Song","year":"2025","journal-title":"Front Immunol"},{"key":"ref39","doi-asserted-by":"publisher","first-page":"180","DOI":"10.1111\/srt.13102","article-title":"Psoriasis and seasonal variation: a systematic review on reports from northern and Central Europe-little overall variation but distinctive subsets with improvement in summer or wintertime","volume":"28","author":"Jensen","year":"2022","journal-title":"Skin Res Technol"},{"key":"ref40","doi-asserted-by":"publisher","first-page":"669","DOI":"10.3390\/ijms23020669","article-title":"The brain-skin Axis in psoriasis-psychological, psychiatric, hormonal, and dermatological aspects","volume":"23","author":"Marek-Jozefowicz","year":"2022","journal-title":"Int J Mol Sci"},{"key":"ref41","doi-asserted-by":"publisher","first-page":"1614863","DOI":"10.3389\/fmed.2025.1614863","article-title":"The role of psychological stress in the pathogenesis of psoriasis","volume":"12","author":"Lei","year":"2025","journal-title":"Front Med (Lausanne)"},{"key":"ref42","doi-asserted-by":"publisher","first-page":"416","DOI":"10.1016\/j.envres.2015.02.022","article-title":"Acute nitrogen dioxide inhalation induces mitochondrial dysfunction in rat brain","volume":"138","author":"Yan","year":"2015","journal-title":"Environ Res"},{"key":"ref43","doi-asserted-by":"publisher","first-page":"6206","DOI":"10.3390\/ijms21176206","article-title":"Oxidative stress as an important contributor to the pathogenesis of psoriasis","volume":"21","author":"Plenkowska","year":"2020","journal-title":"Int J Mol Sci"},{"key":"ref44","doi-asserted-by":"publisher","first-page":"86","DOI":"10.1186\/s12302-022-00668-2","article-title":"Spatiotemporal characterization of aerosols and trace gases over the Yangtze River Delta region, China: impact of trans-boundary pollution and meteorology","volume":"34","author":"Javed","year":"2022","journal-title":"Environ Sci Eur"},{"key":"ref45","doi-asserted-by":"publisher","first-page":"1121","DOI":"10.1080\/15568318.2021.1971345","article-title":"Have the gender differences in commuting been shrinking or persistent? Evidence from two-earner households in the U.S","volume":"16","author":"Kwon","year":"2022","journal-title":"Int J Sustain Transp"},{"key":"ref46","doi-asserted-by":"publisher","first-page":"374","DOI":"10.4103\/ijd.ijd_570_22","article-title":"Psoriasis in pediatric age group","volume":"67","author":"Dhar","year":"2022","journal-title":"Indian J Dermatol"},{"key":"ref47","doi-asserted-by":"publisher","first-page":"667","DOI":"10.1111\/bjd.15086","article-title":"Nonadherence to psoriasis medication as an outcome of limited coping resources and conflicting goals: findings from a qualitative interview study with people with psoriasis","volume":"176","author":"Thorneloe","year":"2017","journal-title":"Br J Dermatol"},{"key":"ref48","doi-asserted-by":"publisher","first-page":"100","DOI":"10.1186\/1476-069x-13-100","article-title":"Effect of ambient temperature on emergency department visits in Shanghai, China: a time series study","volume":"13","author":"Zhang","year":"2014","journal-title":"Environ Health"},{"key":"ref49","year":"2023"},{"key":"ref50","doi-asserted-by":"publisher","first-page":"591839","DOI":"10.3389\/fmicb.2020.591839","article-title":"Deleterious effects of an air pollutant (NO(2)) on a selection of commensal skin bacterial strains, potential contributor to Dysbiosis?","volume":"11","author":"Janvier","year":"2020","journal-title":"Front Microbiol"},{"key":"ref51","doi-asserted-by":"publisher","first-page":"154","DOI":"10.1186\/s40168-018-0533-1","article-title":"Alteration of the cutaneous microbiome in psoriasis and potential role in Th17 polarization","volume":"6","author":"Chang","year":"2018","journal-title":"Microbiome"},{"key":"ref52","doi-asserted-by":"publisher","first-page":"2583227","DOI":"10.1080\/09546634.2025.2583227","article-title":"Laboratory monitoring in patients with moderate to severe plaque psoriasis","volume":"36","author":"Fenkel","year":"2025","journal-title":"J Dermatolog Treat"}],"container-title":["Frontiers in Public Health"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fpubh.2026.1916342\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T10:17:27Z","timestamp":1788949047000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fpubh.2026.1916342\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,9]]},"references-count":52,"alternative-id":["10.3389\/fpubh.2026.1916342"],"URL":"https:\/\/doi.org\/10.3389\/fpubh.2026.1916342","relation":{},"ISSN":["2296-2565"],"issn-type":[{"value":"2296-2565","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,9]]},"article-number":"1916342"}}