Analysis of relationships between symptoms and environmental factors over time

Weekly respiratory symptom information was obtained on a random population of 3800 whites in Tucson. We asked weekly about 14 symptoms representing acute respiratory illnesses (ARI), rhinitis (Rh), and other conditions. The denominator for each week was about 80 randomly chosen subjects from the study population. Interactions of the air pollutants total suspended particulate, oxidants, carbon monoxide, nitrogen oxides for the basin, meteorological information, and aero-allergens were examined. The temporal and spatial interactions between the weekly symptoms and the environmental factors were tested utilizing multivariate methods such as Fourier analyses, multiple regression, and the stimulus-response method, adjusting for lags and controlling for season. Multiple regressions with a smoothing function (using fourier or other methods) yield significant correlations between symptoms and the environmental factors, and separate the ARI's from the Rh's and the miscellaneous symptoms.