Abstract
Introduction: So far, no definitive conclusions have been reached regarding the preventive effect of moisturizers on atopic dermatitis (AD). The variability in results may be due to differences in skin care methods, including bathing and washing, among studies and study design. In hot and humid Japan, bathing and gauze washing have been routinely practiced from the neonatal period, but this may impair the skin barrier function. To address this gap, we determined whether a combination of minimally invasive cleaning methods and moisturizing may prevent AD in infants in Japan. Methods: Mothers of children born between January and September 2019 were instructed in traditional skin care methods (control group; 132 subjects), and mothers of children born between January and September 2020 were instructed in a new skin care method combining less invasive washing and moisturizing (intervention group; 140 subjects). Mothers and babies with and without a history of allergy were recruited, and the incidence of AD at 1 year of age was investigated by questionnaire. Results: Skin care-related behaviors such as face washing, hand washing, and use of moisturizers were more frequent in the intervention group than in the control group. At 6 and 12 months of age, there was no difference in the incidence of AD between the two groups. However, for children born between January and March, the prevalence of AD at 12 months was significantly lower in the intervention group than in the control group (2.9% vs. 21.2%, p = 0.0253). Conclusions: This study suggests that for children born during dry and cold seasons, strengthening the skin barrier function early in life through routine skin care with less invasive washing and moisturizing may prevent AD in Japan. Appropriate skin care practices for newborns and infants may vary in regions and environments.
Plain Language Summary
Impaired skin barrier function is one of the main causes of atopic dermatitis (AD). European guidelines recommend reducing the frequency of bathing so as not to impair the skin barrier function. In addition, to date, many studies have attempted to prevent AD by using moisturizers starting in infancy, with conflicting results. The variation in these results may be due to differences in skin care methods such as washing and moisturizing. In Japan, frequent bathing and gauze washing are commonly used from the neonatal period. The purpose of this study was to determine whether a combination of less invasive washing methods and moisturizing could prevent AD in infants. Mothers of infants born between January and September 2019 were instructed in conventional skin care methods (control group; 132 subjects), and mothers of infants born between January and September 2020 were instructed in a new, less invasive skin care regimen combining washing and moisturizing (intervention group; 140 mothers). Mother/infant dyads with and without a history of allergies were recruited and the incidence of AD at 1 year of age was investigated. The prevalence of AD at 12 months was significantly lower in the intervention group than in the control group for infants born between January and March (2.9% vs. 21.2%). This study suggests that for children born during the dry, cold season, strengthening the skin barrier function early in life with less invasive cleaning and moisturizing skin care may prevent AD.
