Abstract
Objectives: Irritant contact dermatitis (ICD) is a major cause of occupational disease with up to 2000 annual cases compensated in Denmark mainly due to wet work, but also use of occlusive gloves, de-tergents, fresh food, oils and dirt’s. We aimed at systematically reviewing the relation between expo-sure to occupational irritants and ICD and the prognosis of ICD.
Methods: In a systematic review based on PRISMA (Preferred Reporting Items for systematic Reviews and Meta-Analyses) criteria and involving searches in 4 databases (Pubmed., Embase, Web of Science and OSH-update) 1,373 titles were identified. After screening of titles, abstracts and full text reading with application of our eligibility criteria 50 papers from 45 studies. Thirty-four with focus on occupa-tional risk factors for ICD and 12 on prognosis published between 1983 and 2015 were included. Two papers were in German, the remaining in English language. Meta-analyses were not performed due to differences in reported outcome and exposures.
Results: Ten studies focusing on occupational risk factors for ICD were cohort studies, one a retro-spective cohort study, one a nested case-control study and 22 cross-sectional studies. All studies on prognostic factors were cohort studies. In 28 studies with focus on occupational risk factors for ICD or irritant changes, diagnosis was verified clinically, including patch tests in 11 studies, while 14 studies relied on self-reported outcome. Only six studies provided quantitative or semi-quantitative exposure assessments. Six studies were evaluated as medium/high quality, 15 of medium and 13 of low quali-ty.
For wet work the studies supported a moderate association between ICD and wet work, especially frequency of hand washing and mainly minor ICD, especially in combination with other irritants. A dose-response relation to frequency of handwashing was reported, but no threshold level could be described. The level of evidence is considered strong. For occupational exposure to disinfectants and soap the evidence for a causal association to ICD was moderate, while the evidence for a combined effect to other wet work exposures was strong. For occlusive glove exposure without concomitant exposure to other irritants the highest quality studies and supplementary evidence from experi-mental studies supported a limited evidence for an association with ICD. For metalworking exposures, the evidence was consistent with a moderate association between metalworking fluids and mainly minor ICD. For ICD, due to mechanical exposures the evidence was scarce and did not allow for a firm conclusion on risk, and the causal association is limited. For prognosis of ICD there is a high level of evidence for a poor prognosis of complete healing of ICD with a high proportion not having complete healing, a strong evidence for a better prognosis when exposure is ceased through change of occu-pation or work tasks, and a limited evidence for improvement of ICD in relation to work changes. While atopic in some studies had higher risk of ICD, the inclusion of atopic in analyses in general did not alter the effect of occupational irritant exposures for risk of contact dermatitis.
Limitations in the studies included risk misclassification of exposure and outcome. Most study had imprecise exposure assessment as very few included quantitative or semi-quantitative exposure as-sessments, and relied on self-reported exposures. Outcome of supposed ICD was self-reported in several studies, and outcome definition of ICD varied across studies. A large number of studies were cross-sectional adding to risk of selection and information bias.
Conclusion: The review provides strong evidence for an association between irritant exposures and ICD for wet work, detergents and disinfectants, moderate for metalworking fluids, limited for mechan-ical and glove exposure and a strong evidence for a poor prognosis of ICD.
Methods: In a systematic review based on PRISMA (Preferred Reporting Items for systematic Reviews and Meta-Analyses) criteria and involving searches in 4 databases (Pubmed., Embase, Web of Science and OSH-update) 1,373 titles were identified. After screening of titles, abstracts and full text reading with application of our eligibility criteria 50 papers from 45 studies. Thirty-four with focus on occupa-tional risk factors for ICD and 12 on prognosis published between 1983 and 2015 were included. Two papers were in German, the remaining in English language. Meta-analyses were not performed due to differences in reported outcome and exposures.
Results: Ten studies focusing on occupational risk factors for ICD were cohort studies, one a retro-spective cohort study, one a nested case-control study and 22 cross-sectional studies. All studies on prognostic factors were cohort studies. In 28 studies with focus on occupational risk factors for ICD or irritant changes, diagnosis was verified clinically, including patch tests in 11 studies, while 14 studies relied on self-reported outcome. Only six studies provided quantitative or semi-quantitative exposure assessments. Six studies were evaluated as medium/high quality, 15 of medium and 13 of low quali-ty.
For wet work the studies supported a moderate association between ICD and wet work, especially frequency of hand washing and mainly minor ICD, especially in combination with other irritants. A dose-response relation to frequency of handwashing was reported, but no threshold level could be described. The level of evidence is considered strong. For occupational exposure to disinfectants and soap the evidence for a causal association to ICD was moderate, while the evidence for a combined effect to other wet work exposures was strong. For occlusive glove exposure without concomitant exposure to other irritants the highest quality studies and supplementary evidence from experi-mental studies supported a limited evidence for an association with ICD. For metalworking exposures, the evidence was consistent with a moderate association between metalworking fluids and mainly minor ICD. For ICD, due to mechanical exposures the evidence was scarce and did not allow for a firm conclusion on risk, and the causal association is limited. For prognosis of ICD there is a high level of evidence for a poor prognosis of complete healing of ICD with a high proportion not having complete healing, a strong evidence for a better prognosis when exposure is ceased through change of occu-pation or work tasks, and a limited evidence for improvement of ICD in relation to work changes. While atopic in some studies had higher risk of ICD, the inclusion of atopic in analyses in general did not alter the effect of occupational irritant exposures for risk of contact dermatitis.
Limitations in the studies included risk misclassification of exposure and outcome. Most study had imprecise exposure assessment as very few included quantitative or semi-quantitative exposure as-sessments, and relied on self-reported exposures. Outcome of supposed ICD was self-reported in several studies, and outcome definition of ICD varied across studies. A large number of studies were cross-sectional adding to risk of selection and information bias.
Conclusion: The review provides strong evidence for an association between irritant exposures and ICD for wet work, detergents and disinfectants, moderate for metalworking fluids, limited for mechan-ical and glove exposure and a strong evidence for a poor prognosis of ICD.
| Translated title of the contribution | Udredning af årsager til irritativt (toksisk) kontakteksem efter erhvervsmæssig udsættelse for irritative påvirkninger af huden |
|---|---|
| Original language | Danish |
| Number of pages | 116 |
|---|---|
| Publication status | Published - 2017 |