Abstract
Many children with wheezing symptoms in childhood become asymptomatic in adolescence, others have persistent wheezing, while others remit then relapse. We have followed an unselected birth cohort of New Zealand children from age 9 to age 21, with questionnaires, pulmonary function measurements including airway responsiveness, and skin tests, with reviews every 2 or 3 years. Of 815 subjects seen at age 9, 601 (74%) provided data on all subsequent surveys. persistent wheezing (3 or more episodes per year) was defined as wheezing reported at every survey from the age at which it was first documented, remission as permanent loss of previously reported wheezing, relapse as recurrence of wheezing symptoms after negative reports at one or more surveys, and normal as never reporting 3 or more wheezing episodes in a year. At age 21, 21.3% of the 601 subjects had persistent wheezing, 6.8% had had wheezing followed by full remission, 13.4% had had wheezing then remission followed by relapse, 21.8% had wheezing reported at only one survey, 4.8% intermittently reported wheezing with no classifiable pattern, and 31.9% had never reported symptoms. Hence by age 21, 68.1% of the birth cohort had reported recurrent wheezing at one or more surveys, 46.3% had reported wheezing at two or more surveys, and 30% had wheezing persisting into early adult life. The strongest risk factors for persistence to age 21 were atopy to house dust mite and cat, and increased airway responsiveness at age 9, odds ratio >2.0 for each of these factors.