Long-term outcome of early childhood wheezing: population data

Abstract

The adult prognosis of early childhood wheezing is reviewed using data from three studies (in Melbourne, Tasmania and Britain) which have followed population-based samples of 7 year old children with a history of asthma or wheezing illness into their early thirties. About one quarter of these wheezy children, recruited in the 1960s, reported recent wheeze as adults, but there was considerable variation in the severity of adult wheezing in the three studies. A pattern of remissions and relapses was common over approximately 25 yrs of follow-up. Thus, teenagers who appeared to have outgrown an earlier wheezing tendency remained at risk of future wheezing, particularly if they took up cigarette smoking. Adults who have outgrown their childhood wheezing tendency have ventilatory function similar to healthy controls, suggesting that the abnormalities of neonatal airway function which precede transient wheezing in early childhood do not predict adult obstructive lung disease. In contrast, asthmatic children who continue to wheeze as adults have poorer baseline spirometry than healthy controls, even after inhaled salbutamol. The degree of reduction correlates with the duration and persistence of wheezing. Bronchial hyperresponsiveness and reduced levels of ventilatory function in childhood predict both persistence of wheeze and level of bronchial responsiveness in adult life. These may simply be markers of disease severity, but there is evidence of progressive deterioration of ventilatory function through adolescence in children with persistent symptoms. These progressive changes may underlie the observed association between chest illness in childhood and later adult life.