Skin cancer diagnosis associated with asthma and hay fever: a nationwide cross-sectional study.

Asthma is a respiratory disorder caused by airway inflammation which may worsen after allergen exposure. Recent cohort studies demonstrate a positive association between skin cancer and asthma or hay fever (allergy to outdoor allergens such as pollen). Nationally-representative data for adults in the United States remains limited. We aimed to characterize skin cancer prevalence among individuals in the United States who have asthma or hay fever. To achieve this aim, we extracted nationwide cross-sectional data from 16,277 adult participants (total survey-weighted sample = 174,765,931) of the Third National Health and Nutrition Examination Survey from 1988 to 1994. This study uses survey-weighted regression to compare the nationwide prevalence of skin cancer among participants with or without a history of asthma or hay fever. Sensitivity analysis examined the influence of sex, 25-hydroxyvitamin D, chronic bronchitis or emphysema, geographical region, urban proximity, and oral glucocorticoid use. Of the included participants, the age-adjusted prevalence of skin cancer was 7.2%, similar to national estimates. Skin cancer prevalence was higher among participants who had asthma with hay fever (adjusted prevalence ratio, 1.79; 95% confidence interval, 1.16, 2.76), but not among participants with asthma only or hay fever only. Similarly, skin cancer prevalence was higher for those with asthma and positive pollen allergen skin prick testing (SPT), but not for those with hay fever and positive pollen SPT. No association was noted between skin cancer and wheezing triggered by pollen. Hay fever or immunoglobulin-E sensitization to pollen may increase skin cancer prevalence among individuals with a history of asthma.