Table 4.

ORs for the association of indicator elements of PM_2.5 sources with the occurrence of ST segment depressions in multipollutant models.^a

		> 0.1 mV (n = 62)b		> 0.1mV + slope (n = 46)c
Source indicator	Lag	OR	95% CI	OR	95% CI
Si (crustal)	Lag 0	0.73	0.39–1.38	0.67	0.33–1.36
	Lag 1	0.48	0.25–0.93	0.34	0.15–0.81
	Lag 2	0.78	0.35–1.71	0.81	0.33–2.00
	Lag 3	1.95	0.69–5.48	1.90	0.64–5.65
S (long-range transport)	Lag 0	0.70	0.25–1.95	0.84	0.29–2.47
	Lag 1	0.58	0.23–1.47	0.89	0.34–2.32
	Lag 2	1.08	0.44–2.63	1.36	0.54–3.45
	Lag 3	1.60	0.73–3.48	1.12	0.53–2.40
Ni (oil combustion)	Lag 0	0.78	0.30–2.04	1.10	0.36–3.37
	Lag 1	1.20	0.58–2.46	1.16	0.45–2.96
	Lag 2	1.15	0.61–2.18	1.64	0.84–3.20
	Lag 3	1.02	0.41–2.54	1.63	0.64–4.14
Cl (salt)	Lag 0	1.03	0.79–1.34	1.13	0.80–1.62
	Lag 1	0.88	0.56–1.38	0.99	0.58–1.68
	Lag 2	1.02	0.62–1.69	1.55	0.87–2.76
	Lag 3	1.27	0.85–1.91	1.45	0.94–2.25
ABS (local traffic)	Lag 0	0.92	0.36–2.37	0.74	0.25–2.23
	Lag 1	1.83	0.73–4.59	1.76	0.62–5.00
	Lag 2	4.46	1.69–11.79	4.86	1.55–15.26
	Lag 3	0.92	0.40–2.12	0.97	0.39–2.41

ORs calculated for an increase of interquartile range of pollutant. Number of measurements = 312 for lag 0, 322 for lag 1, 314 for lag 2, and 311 for lag 3.

^aThe statistical model included all five indicator elements, a dummy for each subject, linear terms for time trend, temperature (lag 3) and relative humidity (lag 3), and a penalized spline (df = 3) for heart rate during exercise test.

^bST segment depression > 0.1 mV; n = number of events at minimum (lag 0).

^cST segment depressions > 0.1 mV with horizontal or downward slope; n = number of events at minimum (lag 0).