Table 2.

Characteristics of the study population

	Included		Excluded		Declining participation		pa	pb	pc
	n	%	n	%	n	%
Subjects	430	53.1	289	35.7	91	11.2
Male	234	54.4	146	50.5	48	52.7	0.304	0.771	0.711
Age, mean ± SD, years	71.8 ± 10.6		81.5 ± 9.1		77.2 ± 13.1		<0.001	<0.001	0.004
Stroke	273	63.5	263	91.0	64	70.3	<0.001	0.215	<0.001
Ischemic	254		234		56
Hemorrhagic	19		28		8
Unspecified	0		1		0
mRS score >3	36	8.4	172	59.5	15	16.5	<0.001	0.018	<0.001
GFR
Mean ± SD, ml/min	81.7 ± 32.1		60.4 ± 29.2		68.5 ± 34.5		<0.001	<0.001	0.033
n	429		281		84
BMI
Mean ± SD	26.8 ± 4.3		24.9 ± 4.9		25.8 ± 4.3		<0.001	0.070	0.123
n			275		84
Postbasic education	181/429	42.2	37/266	13.9	14/85	16.5	<0.001	<0.001	0.560
Ischemic heart disease	55	12.8	55	19.0	19	20.9	0.023	0.045	0.698
Previous stroke	73	17.0	89	30.8	24	26.4	<0.001	0.036	0.421
Peripheral artery disease	21	4.9	15	5.2	3	3.3	0.853	0.782	0.580
Congestive heart failure	21	4.9	52	18.0	8	8.8	<0.001	0.140	0.036
Smoking	206	47.9	94/283	33.2	44/90	48.9	<0.001	0.865	0.007
Atrial fibrillation	85/429	19.8	106	36.7	20/90	22.2	<0.001	0.605	0.011
Hyperlipidemia	310/323	96.0	210/222	94.6	65/69	94.2	0.449	0.515	1.000
Hypertension	262	60.9	214	74.0	69	75.8	<0.001	0.007	0.735
Diabetes	74	17.2	61	21.1	20	22.0	0.189	0.282	0.860

p^a, p^b and p^c indicate significance for the following comparisons: included vs. excluded (p^a), included vs. declining participation (p^b), and excluded vs. declining participation (p^c). For variables with missing values, the valid number of cases is given for each group.