Association of ambient air pollution and meteorological factors with primary care visits at night due to asthma attack

Table 3 Associations^a between air pollutants and primary care visits at night due to asthma attack by seasonal subgroups (single-pollutant model)

Air pollutants	Unit increment	April–June			July–August			September–November			December–March
Air pollutants	Unit increment	OR	95 % CI		OR	95 % CI		OR	95 % CI		OR	95 % CI
NO₂	10 ppb	0.881	0.594	1.306	1.110	0.557	2.214	1.125	0.784	1.614	0.874	0.607	1.259
Ozone	10 ppb	1.003	0.847	1.187	1.118	0.934	1.337	0.984	0.794	1.221	0.903	0.694	1.174
SPM	10 μg/m³	0.942	0.828	1.072	1.021	0.829	1.256	1.006	0.882	1.148	0.726	0.552	0.956
PM_2.5	10 μg/m³	0.998	0.882	1.129	0.958	0.776	1.182	0.991	0.885	1.109	1.039	0.883	1.222
PM₁₀	10 μg/m³	0.988	0.936	1.043	0.968	0.818	1.146	0.971	0.900	1.047	1.022	0.902	1.158
OBC	0.1 μg/m³	1.019	0.961	1.079	1.058	0.965	1.160	1.023	0.973	1.075	0.984	0.937	1.033

Data are adjusted for daily mean atmospheric pressure, relative humidity, temperature, wind speed and hours of daylight
^aAssociations are shown as odds ratios (ORs) and their 95 % confidence intervals (CIs) per unit increment of each pollutant

ISSN: 1347-4715