A population study of childhood maltreatment and asthma diagnosis: differential associations between child protection database versus retrospective self-reported data.

OBJECTIVE: Despite growing evidence from longitudinal studies of a link between early-life stress and the development of asthma, very few of these examine one of the most severe types of early-life stress: childhood maltreatment. Cross-sectional studies on this topic have relied on retrospective self-reports of maltreatment. This study investigates associations between childhood maltreatment indicated by child protection agency records versus self-reports and lifetime asthma diagnosis in young adults, adjusting for socioeconomic status and mental disorders.
METHODS: A nationally representative general population survey of DSM-IV mental disorders in New Zealand (n = 12,992) obtained information on lifetime diagnoses of chronic physical conditions. Information from a subsample of survey respondents aged 16 to 27 years (n = 1413) was linked with a national child protection database to identify respondents with a history of agency involvement, which was used as a proxy for childhood maltreatment. Retrospective reports of maltreatment were also obtained.
RESULTS: Child protection agency history was associated with elevated odds (odds ratio = 2.88 [95% confidence interval = 1.7-4.74]) of a lifetime diagnosis of asthma. After adjusting for a variety of indicators of socioeconomic status, lifetime mental disorders, lifetime smoking, and body mass index, this association remained significantly elevated (odds ratio = 2.26 [95% confidence interval = 1.33-3.83]). Retrospectively self-reported maltreatment in childhood was not associated with asthma.
CONCLUSIONS: Childhood maltreatment was associated with elevated odds of asthma diagnosis. These findings are consistent with the possibility that early-life stress may be one of the environmental factors that increase the risk of asthma in genetically vulnerable individuals.