Table 1– Lifestyle and other characteristics at baseline according to serum selenium level

	Serum selenium			p_trend^§	p_het^ƒ
	Low^#	Medium^¶	High⁺
Subjects n	965	1141	1227
Smoking characteristics
Exposure pack-yrs	32.4±28.4	28.5±24.0	24.5±23.4	<0.001	0.94
Current smokers	64.0	56.7	46.8	<0.001	<0.001
S-cotinine ng·mL⁻¹
<100	38.9	46.8	57.5
100–360	28.1	25.9	22.4	<0.001	<0.001
>360	33.0	27.3	20.1
Smokers in 1970–1971	74.9	68.6	63.4	<0.001	<0.001
Never-smokers	8.2	11.3	13.3	<0.001	0.001
Alcohol use
Alcoholic beverages per week
0	10.6	9.8	12.7
1–21	58.0	64.0	60.8	0.008	0.007
≥22	31.4	26.2	26.4
Beer drinkers	78.7	74.8	69.8	<0.001	<0.001
Beer beverages per week	12.9±11.3	10.5±8.3	10.5±8.7	<0.001	0.003
Wine drinkers	48.0	54.3	58.3	<0.001	<0.001
Wine beverages per week	7.4±6.9	7.7±7.8	7.4±6.2	0.92	0.51
Spirits drinkers	50.9	53.8	53.4	0.29	0.36
Spirits beverages per week	7.1±6.1	6.1±4.9	5.9±4.9	<0.001	0.14
Dietary factors
Salt^##	16.0	13.0	9.1	<0.001	<0.001
Fat^¶¶	57.3	51.2	47.6	<0.001	<0.001
Occupational exposure
Long-term dust exposure⁺⁺	6.9	7.1	8.5	0.16	0.30
Other characteristics
Chronic bronchitis	19.9	13.7	10.7	<0.001	<0.001
Peak flow L·min⁻¹	481±104	509±97	516±92	<0.001	0.006
Low social class^§§	60.2	50.9	46.5	<0.001	<0.001
Age yrs	63.5±5.3	62.6±5.1	62.7±5.1	0.001	0.007

Data are presented as mean±sd or %, unless otherwise stated. p_trend: p-value for trend; p_het: p-value for heterogeneity. ^#: 0.4–1.0 μmol·L⁻¹; ^¶: 1.1–1.2 μmol·L⁻¹; ⁺: 1.3–3.0 μmol·L⁻¹; ^§: Kendall’s tau B or test for linearity in ANOVA; ^ƒ: Chi-squared test (likelihood ratio) or test for deviation from linearity in ANOVA; ^##: uses more than others; ^¶¶: does not avoid fatty foods; ⁺⁺: ≥5 yrs; ^§§: class IV–V.