Study Design and Study Population
The recruitment for the PATCH study was conducted at Keelung Chang Gung Memorial Hospital from October 2007 to September 2010. The comprehensive enrollment process, including the requirements for inclusion and exclusion, has been previously described.13 Briefly, pregnant mothers were invited to enroll in the study at a gestational age of 32 weeks. After giving consent, the mother’s precise prenatal information was collected. Upon delivery, healthy newborns more than 34 weeks of gestation were enrolled. Perinatal information and cord blood samples were collected at birth. At the ages of 6 months, 1 year, 1.5 years, 2 years, and annually thereafter, enrolled children came to the hospital for a follow-up visit. The study was approved by the Human Research Ethics Committee of Chang Gung Memorial Hospital (No. 100-0201B).
At the age of 7 years, atopic diseases were diagnosed by pediatric allergists and pulmonologists. The diagnosis of asthma was based on the 2017 Global Initiative for Asthma guidelines.14Repeated pulmonary function tests were performed for ambiguous cases. Bronchodilator or methacholine challenge tests were also performed when appropriate. The diagnosis of allergic rhinitis was based on typical symptoms, physical examinations, and allergy tests.15As described by Hanifin, atopic dermatitis was diagnosed by the typical manifestations of recurrent pruritic eczema with exudates, dryness, or lichenification.16