Does air pollution cause asthma exacerbations in children?

Respiratory and other health effects reported in children exposed to the World Trade Center disaster of 11 September 2001

BACKGROUND

Effects of the World Trade Center (WTC) disaster on children's respiratory health have not been definitively established.

OBJECTIVE

This report describes respiratory health findings among children who were < 18 years of age on 11 September 2001 (9/11) and examine associations between disaster-related exposures and respiratory health.

METHODS

Children recruited for the WTC Health Registry (WTCHR) included child residents and students (kindergarten through 12th grade) in Manhattan south of Canal Street, children who were south of Chambers Street on 9/11, and adolescent disaster-related workers or volunteers. We collected data via computer-assisted telephone interviews in 2003-2004, with interview by adult proxy for children still < 18 years of age at that time. We compared age-specific asthma prevalence with National Health Interview Survey estimates.

RESULTS

Among 3,184 children enrolled, 28% were < 5 years of age on 9/11; 34%, 5-11 years; and 39%, 12-17 years. Forty-five percent had a report of dust cloud exposure on 9/11. Half (53%) reported at least one new or worsened respiratory symptom, and 5.7% reported new asthma diagnoses. Before 9/11, age-specific asthma prevalence in enrolled children was similar to national estimates, but prevalence at interview was elevated among enrollees < 5 years of age. Dust cloud exposure was associated with new asthma diagnosis (adjusted odds ratio = 2.3; 95% confidence interval, 1.5-3.5).

CONCLUSIONS

Asthma prevalence after 9/11 among WTCHR enrollees < 5 years of age was higher than national estimates, and new asthma diagnosis was associated with dust cloud exposure in all age groups. We will determine severity of asthma and persistence of other respiratory symptoms on follow-up surveys.