A retrospective cohort study of stroke onset: implications for characterizing short term effects from ambient air pollution

Table 1 Characteristics of 337 stroke patients who participated in the survey

Characteristic	Category	N	%
Sex*	Male	173	51.5
	Female	163	48.5
Age *	< 65 years	105	31.3
	65-74 years	67	19.9
	75-84 years	88	26.2
	≥ 85 years	76	22.6
Stroke sub-type *	TIA	67	19.9
	Ischemic	226	67.3
	Hemorrhagic	41	12.2
	Unknown	2	0.6
Previous stroke *	Yes	114	34.0
	No	221	66.0
Hypertension *	Yes	241	71.9
	No	94	28.1
Diabetes *	Yes	72	21.5
	No	263	78.5
Smoking status †	Current regular	32	9.5
	Current occasional	53	15.8
	Former	126	37.5
	Never	122	36.3
	Unknown	3	0.9
Location at stroke †	≤ 15 minute drive from home	283	84.5
	> 15 minute drive from home, but in Edmonton	47	14.0
	Outside of Edmonton	5	1.5
Timing of stroke onset †	Morning (06:00-11:59)	100	29.8
	Afternoon (12:00 - 17:59)	70	20.8
	Evening (18:00 - 23:59)	44	13.1
	Overnight (00:00 - 05:59)	19	5.7
	Unknown	103	30.7
Awake at stroke †	Yes	248	73.8
	No	51	15.2
	Unknown	37	11.0
Activity at stroke †	Sleeping	79	23.5
	Exercising	15	4.5
	Sitting/resting	167	49.7
	Exerting at work	11	3.3
	Other	64	19.0
Inside/outside at stroke †	Inside	302	89.9
	Outside	15	4.5
	In vehicle	16	4.8
	Other	3	0.9

ISSN: 1476-069X