J Clin Aesthet Dermatol. 2025;18(9):65–67.
by Sara Osborne, MD; Olivia Kam, MD; Carolynne Vo, BS; Raquel Wescott, MD; Shivani Thacker, DO; and Jashin Wu, MD
Ms. Osborne is with the University of Minnesota Medical School in Minneapolis, Minnesota. Ms. Kam is with the Stony Brook School of Medicine in New York, New York. Ms. Vo is with the University of California, Riverside School of Medicine in Riverside, California. Ms. Wescott is with the University of Nevada, Reno School of Medicine in Reno, Nevada. Dr. Thacker is with KPC Hemet Medical Center in Santa Ana, California. Dr. Wu is with the University of Miami Miller School of Medicine in Miami, Florida.
FUNDING: No funding was provided for this article.
DISCLOSURES: Dr. Wu is or has been an investigator, consultant, or speaker for AbbVie, Almirall, Amgen, Arcutis, Aristea Therapeutics, Bausch Health, Boehringer Ingelheim, Bristol-Myers Squibb, Dermavant, DermTech, Dr. Reddy’s Laboratories, Eli Lilly, EPI Health, Galderma, Janssen, LEO Pharma, Mindera, Novartis, Pfizer, Regeneron, Samsung Bioepis, Sanofi Genzyme, Solius, Sun Pharmaceutical, UCB, and Zerigo Health. The remaining authors have no conflicts of interest to disclose.
Abstract: Objective: The goal of this study was to examine the relationship between psoriasis and occupational organic dust exposure among United States (US) adults 20 to 79 years of age. Methods: We merged two, two-year cycles (2009 to 2010 and 2011 to 2012) of data from the National Health and Nutrition Examination Survey (NHANES). Of 10,990 participants, 483 were excluded due to incomplete data, resulting in a cohort of 10,507 individuals. We utilized STATA/SE 18.0 for multivariable logistic regression analyses. Results: Among individuals with psoriasis, the prevalence of organic dust exposure was 32 percent compared to 22 percent with organic dust exposure among those without psoriasis. There was a significant association between psoriasis and organic dust exposure among patients ages 20 to 79 years after adjusting for potential confounding variables (adjusted odds ratio [AOR]: 1.68; 95% confidence interval [CI]: 1.19–2.36; p=0.004). There was significant organic dust exposure among female participants with psoriasis (p=0.040), and increased rates of exposure among adults with psoriasis ages 40 to 59 years (p=0.038) and adults with psoriasis ages 60 to 79 years (p=0.034). There was a higher percentage of psoriasis participants with over fifteen years of organic dust exposure (43%) compared to those without psoriasis (23%) (p=0.038). Limitations: Limitations include the possibility of recall bias due to self-reporting and inability to control for psoriasis severity. Conclusion: Organic dust exposure was significantly associated with psoriasis in this study. These results remained significant when examining female subgroups, ages 40 to 59 years, and ages 60 to 79 years. There was also a statistically significant presence of psoriasis among individuals with occupational organic dust exposure of fifteen years or more. Keywords: Psoriasis, organic dust exposure, occupational health, National Health and Nutrition Examination Survey, adults
Introduction
Psoriasis is a dermatologic condition that is both chronic and inflammatory in nature. The development of psoriasis involves a genetic predisposition accompanied by an inciting environmental trigger. Stress, smoking, obesity, and alcohol are examples of well-established environmental triggers. Psoriasis has also been linked to inorganic environmental triggers, including heavy metals.1 However, the exploration of organic triggers, notably exposure to organic dust in occupational settings, remains insufficient despite the substantial role environmental factors play in the development of psoriasis. Our study analyzed the association between psoriasis and occupational organic dust exposure among United States (US) adults 20 to 79 years of age, utilizing the latest accessible data from the National Health and Nutrition Examination Survey (NHANES) for occupational organic dust exposure, from 2009 to 2012.2
The NHANES response rate among adults 20 to 79 years of age between 2009 to 2012 was 71.8 percent. Of the 10,990 participants, data on psoriasis and occupational organic dust exposure were available in 10,507 participants (95.6% response rate). Psoriasis status was assessed by the question, “Have you ever been told by a doctor or other health professional that you had psoriasis?” Organic dust exposure was assessed by the question, “In any job, have you ever been exposed to dust from baking flours, grains, wood, cotton, plants, or animals?” If the participant responded “yes,” duration of organic dust exposure was assessed by the question, “Please give me the total number of years for all jobs where this has happened.” In cases where individuals held multiple positions associated with organic dust exposure, the total duration of exposure was calculated by summing the years spent at each job to derive a cumulative figure for the total years of exposure. Less than one year of occupational exposure was recorded as zero. Multivariable logistic regression analyses were performed using STATA/SE 18.0 to assess the relationship between psoriasis and organic dust exposure. Age, income, education, sex, race, tobacco use, diabetes, and body mass index were controlled for in our models. Additionally, we controlled for asthma given its association with both occupational organic dust exposure and psoriasis.3,4
In our analysis, the prevalence of occupational organic dust exposure in patients with psoriasis was 32.0 percent weighted, and 22.0 percent in those without psoriasis (Table 1). There was a significant association between psoriasis and organic dust exposure among patients 20 to 79 years of age after adjusting for potential confounding variables (adjusted odds ratio [AOR], 1.68; 95% confidence interval [CI]: 1.19–2.36; p=0.004) (Table 2). Analysis of gender subgroups showed significantly increased odds of organic dust exposure among female patients with psoriasis (AOR: 1.87; 95% CI: 1.03–3.39; p=0.040). Analysis of age subgroups yielded statistically significant results among adults 40 to 59 years of age (AOR: 1.697; 95% CI: 1.03–2.75; p=0.038) and 60 to 79 years of age (AOR: 1.95; 95% CI: 1.05–3.63; p=0.034). Among individuals exposed to organic dust, those with a history of fifteen or more years of exposure constituted 43 percent of patients with psoriasis, in contrast to 23 percent in the non-psoriasis cohort with equivalent exposure durations (AOR: 2.03; 95% CI: 1.04–3.94; p=0.038) (Figure 1).
These results indicate a significant association between psoriasis and occupational organic dust exposure in the US adult population, even after controlling for asthma, a potential confounding variable linked to both psoriasis and organic dust exposure.3,4 Workers in grain milling, woodworking, carpentry, agriculture, or textiles, who are regularly exposed to organic particles from sources like baking flours, grains, wood, cotton, plants, and animals, appear to be at an increased risk for developing psoriasis. Furthermore, prolonged exposure to organic dusts exceeding 15 years was significantly linked to a heightened risk of developing psoriasis. This association remained significant in subgroup analyses of women and adults 40 to 79 years of age. The higher risk in older age groups may reflect the cumulative impact of long-term exposure, as we found that psoriasis was more prevalent among individuals with over fifteen years of exposure. The association between psoriasis and organic dust exposure may be the result of immune dysregulation. Organic dust has been linked to increased inflammatory responses, involving TNFa, Th1/Th17, and macrophages, all of which play a role in the pathogenesis of psoriasis.3,5 Additionally, TLR9 has been linked to the pro-inflammatory pattern recognition receptor pathway in organic dust responses; TLR9 has also been associated with the activation of dendritic cells in psoriasis.6
The study’s limitations include the possibility of recall bias due to the reliance on participants’ self-reported medical conditions and that we were unable to control for psoriasis severity. Further investigations are warranted in large, representative US adult populations to determine whether a causal relationship exists between psoriasis and occupational organic dust exposure.
References
- Chen Y, Pan Z, Shen J, et al. Associations of exposure to blood and urinary heavy metal mixtures with psoriasis risk among U.S. adults: A cross-sectional study. Sci Total Environ. 2023;887:164133.
- Centers for Disease Control and Prevention (CDC). National Center for Health Statistics (NCHS). National Health and Nutrition Examination Survey Data. Web site.https://wwwn.cdc.gov/nchs/nhanes/Default.aspx. Accessed October 29, 2023.
- Wunschel J, Poole JA. Occupational agriculture organic dust exposure and its relationship to asthma and airway inflammation in adults. J Asthma. 2016;53(5):471–477.
- Wang J, Ke R, Shi W, et al. Association between psoriasis and asthma risk: A meta-analysis. Allergy Asthma Proc. 2018;39(2):103–109.
- Arican O, Aral M, Sasmaz S, Ciragil P. Serum levels of TNF-α, IFN-γ, IL-6, IL-8, IL-12, IL-17, and IL-18 in patients with active psoriasis and correlation with disease severity. Mediators Inflamm. 2005;2005(5):273–279.
- Tokuyama M, Mabuchi T. New treatment addressing the pathogenesis of psoriasis. Int J Mol Sci. 2020;21(20):7488.