Asthma onset and relapse in adult life: the British 1958 birth cohort study.

BACKGROUND

Few studies have investigated adult-onset wheezing because of difficulties identifying childhood asthma or wheeze retrospectively.

OBJECTIVE

To investigate risk factors for the incidence and recurrence of wheezing illness in adulthood.

METHODS

British children born during 1 week in 1958 (N = 18,558) were followed up periodically. Information on wheezing illness was obtained via parental interviews at ages 7, 11, and 16 years and via cohort member interviews at ages 23, 33, and 42 years. At ages 44 to 45 years a subset (N = 12,069) was targeted for biomedical survey, and total IgE and specific IgE responses to grass, cat, and dust mite were measured.

RESULTS

Incidences of wheezing illness at ages 17 to 33 and 34 to 42 years were positively associated with atopy (any specific IgE -0.3 kU/L) and cigarette smoking. For ages 17 to 42 years, proportions of incident "asthma" and incident "wheeze without asthma" associated with atopy, adjusted for sex and smoking, were estimated to be 34% (95% confidence interval [CI], 26%-42%) and 5% (95% CI, 1%-9%), respectively, whereas proportions associated with cigarette smoking, adjusted for sex and atopy, were estimated to be 13% (95% CI, 0%-26%) and 34% (95% CI, 27%-40%), respectively. Among participants with no reported wheezing illness at ages 17 to 23 or 33 years, wheeze prevalence at the age of 42 years was positively associated with symptoms in childhood.

CONCLUSIONS

Onset and relapse of wheezing illness in adult life seem to be similarly affected by atopy and cigarette smoking, although the nature of these effects may differ between asthma and wheeze without asthma. Children who apparently "outgrow" early wheezing illness remain at increased risk for relapse or recurrence during midlife.