Rainfall-Associated Bronchospasm Epidemics: The Epidemiological Effects of Air Pollutants and Weather Variables

Table 4

Results of crude and adjusted negative binomial regression and of the effect of pollutants and climate factors on respiratory hospital admissions (ratio of increase in hospital admissions in day per unit of increase in pollutants and climate factors daily average) in the nonepidemic periods.

Variables	Crude and 95% CI		Adjusted and 95% CI
O3 (ppm)	1.018 (1.001–1.034)	0.036	1.012 (0.992–1.032)	0.241
PM10 (µg/m^3)	1.000 (1.000–1.000)	0.692	1.000 (1.000–1.000)	0.684
NO (ppm)	0.999 (0.996–1.002)	0.613	0.998 (0.994–1.003)	0.477
NO2 (ppm)	1.005 (0.999–1.010)	0.100	1.010 (1.001–1.019)	0.023
NOx (ppm)	1.000 (0.998–1.002)	0.727	1.002 (0.999–1.005)	0.157
CO (ppm)	1.000 (1.000–1.000)	0.646	1.000 (0.999–1.000)	0.067
SO2 (ppm)	0.990 (0.978–1.002)	0.101	0.988 (0.972–1.004)	0.153
Temperature (°C)	1.041 (0.953–1.137)	0.374	0.867 (0.186–4.038)	0.855
Relative humidity (%)	0.979 (0.944–1.015)	0.254	1.318 (0.786–2.210)	0.296
Total rainfall (mm)	0.974 (0.927–1.023)	0.289	0.685 (0.392–1.198)	0.185
Total evaporation (mm)	1.002 (0.998–1.006)	0.287	1.008 (0.939–1.083)	0.819
Wind speed (m/s)	1.100 (0.677–1.786)	0.701	2.775 (0.549–14.034)	0.217