The 1997 Malaysian Forest Fires: Respiratory Hospitalizations in Persons with a History of Chronic Obstructive Pulmonary Disease

Joshua A. Mott, U.S. Centers for Disease Control and Prevention (CDC)
Clinton J. Alverson, U.S. Centers for Disease Control and Prevention (CDC)
David Mannino, U.S. Centers for Disease Control and Prevention (CDC)
Andrew Kiyu, Sarawak Health Department, Malaysia
Jamila Hashim, Sarawak Health Department, Malaysia
Ken Falter, U.S. Centers for Disease Control and Prevention (CDC)
Stephen Redd, U.S. Centers for Disease Control and Prevention (CDC)

To investigate the respiratory health effects of the 1997 Malaysian haze episode, admissions to hospitals in Kuching, Malaysia, were selected from a database of all hospital admissions that occurred in the state of Sarawak from 1/1/1995-12/31/1998. We identified cohorts of persons whose members were admitted for respiratory problems during January 1 through July 31 of each year, 1995-1997. These persons were then followed until first re-admission for the same condition during the August-December of each year. We compared the survival curve of time to first readmission for the 1997 cohort (exposed to the haze) to the survival curves for the 1995 and 1996 cohorts ("pre-haze" cohorts). Persons with previous admissions for respiratory diseases were more likely to be re-hospitalized for respiratory diseases during the follow-up period in 1997 than during the pre-haze years. These findings suggest an association between forest-fire smoke exposure and increased respiratory hospitalizations among susceptible adults.