ANALYSIS OF THE RELATIONSHIPS BETWEEN ENVIRONMENTAL-FACTORS (AEROALLERGENS, AIR-POLLUTION, AND WEATHER) AND ASTHMA EMERGENCY ADMISSIONS TO A HOSPITAL IN MEXICO-CITY

There have been several studies of the relationships between environme ntal factors, particularly air pollution, and attacks of asthma. Most of these studies have ignored the potential confounding effects of aer oallergens such as pollens and fungal spores. We report a statistical analysis of the relationships between emergency admissions for asthma to a hospital in Mexico City and daily average airborne concentrations of pollen, fungal spores, air pollutants (O-3, NO2, SO2, and particul ates) and weather factors. Asthma admissions had a seasonal pattern wi th more during the wet season (May-October) than the dry season (Novem ber-April). There were few statistical associations between asthma adm issions and air pollutants for the three age groups studied (children under 15 years, adults, and seniors [adults over 59 years]) in either season. Grass pollen was associated with child acid adult admissions f or both the wet and dry seasons, and fungal spores were associated wit h child admissions during both the wet and dry seasons. The analysis w as done with environmental data averaged over the day of admission and the 2 previous days. Our results suggest that aeroallergens may be st atistically associated more strongly with asthma hospital admissions t han air pollutants and may act as confounding factors in epidemiologic studies.