Prenatal exposure to tobacco was associated with increased risk for pediatric psoriasis, according to cohort study data published in the Journal of the American Academy of Dermatology.
Data were extracted from the Danish National Birth Cohort (DNBC), a nationwide cohort of pregnant women recruited and followed between 1996 and 2002. DNBC enrollees participated in 4 prenatal and postnatal telephone interviews that captured lifestyle and environmental factors. Parents were then invited to complete follow-up questionnaires at child ages 7, 11, and 18 years. Tobacco exposure was extracted from the questionnaires administered at gestational week 12, child age 6 months, and child age 11 years. Diagnosis of pediatric psoriasis was ascertained from the follow-up questionnaire administered at child age 11 years. Multivariable logistic regression was performed to estimated odds ratios (ORs) of offspring psoriasis by tobacco exposure. Analyses were adjusted for parental socio-occupational status and maternal psoriasis.
Data from 25,812 mother-child dyads were included in analyses. During 11 years of follow-up, 281 children (1.1%) were diagnosed as having psoriasis. Offspring with prenatal tobacco exposure were at significantly increased odds of psoriasis (adjusted OR [aOR], 1.39; 95% CI, 1.06-1.82) compared with unexposed offspring. A dose-response relationship was also observed between tobacco and psoriasis risk; children in the highest bracket of tobacco exposure (≥ cigarettes/day) had a 3-fold increased risk for psoriasis (aOR, 2.92; 95% CI, 1.20-7.10). Children with tobacco exposure in infancy and childhood were also at increased risk for psoriasis in univariable models, although the associations were attenuated after adjustment for maternal psoriasis and prenatal tobacco exposure. Maternal use of nicotine replacement therapy (NRT) had no apparent effect on odds of psoriasis overall, but prenatal NRT exposure was associated with increased odds of pediatric psoriasis in the offspring of mothers with psoriasis only (aOR, 4.46; 95% CI, 1.26-15.82).
As study limitations, investigators noted that psoriasis status was ascertained by self-report; diagnoses could not be clinically determined. In addition, self-report of tobacco use may have resulted in underestimation of exposure.
The data suggest an association between prenatal tobacco exposure and risk for pediatric psoriasis and coalesce with literature evidence suggesting that active smoking may exacerbate psoriasis symptoms in adults. The investigators believe that the results strongly suggest that smoking during pregnancy may increase psoriasis risk in offspring. The apparent association between NRT and psoriasis risk in offspring of mothers with psoriasis warrants further investigation, the study suggests.
Disclosure: One study author declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Groot J, Nybo Andersen AM, Blegvad C, et al. Prenatal, infantile, and childhood tobacco exposure and risk of pediatric psoriasis in the Danish National Birth Cohort offspring [published online January 20, 2020]. J Am Acad Dermatol. doi: 10.1016/j.jaad.2019.09.038