Secular trends of atopic dermatitis and its comorbidities in United States children between 1997 and 2018

Previous studies found increased prevalence of childhood atopic dermatitis (AD) in the United States over the past few decades. It is unknown whether the prevalence of AD has plateaued or whether AD comorbidities changed over time. The main objective of this study is to assess the prevalence and secular trends of AD and its comorbidities. We analyzed data on 259,818 children, ages 0 to 17 years, from the National Health Interview Survey, 1997–2018, using logistic regression models. The prevalence (95% confidence interval) of childhood AD steadily increased from 2000 [7.3% (6.8–7.9%)] to 2011 [12.8% (12.1–13.5%)] and remained consistent until 2018 [12.6% (11.6–13.5%)]. In logistic regression models, the odds of AD were significantly increased in all years from 2003 to 2018 compared to 1997. However, the increased odds of AD over time were attenuated when adjusting for socio-demographic factors. AD prevalence increased in most socio-demographic groups, but changed variably by age group, race/ethnicity, and region. There were significant trends of AD comorbidities over time, with increasing prevalence of attention deficit (hyperactivity) disorder, and decreasing prevalence of hay fever and depression/sadness. AD prevalence in US children increased between 1997 and 2011, remaining consistent until 2018 with an overall increase of 59%. Prevalence of comorbid hay fever and sadness/depression decreased, while ADD/ADHD increased. Given divergent trends of AD prevalence by socio-demographic characteristics, future studies are better equipped to identify contributing factors of prevalence change