Supplemental Table 1: Distribution of Selected Demographic and Lifestyle Factors by Levels

Supplemental Table 1: Distribution of selected demographic and lifestyle factors by levels of coffee consumption, the Singapore Chinese Health Study 1993-2006

Number of cups of coffee per day
Non-drinkers / <1 / 1-<2 / ≥2 / p—value*
Number of subjects
Age at interview, mean (SD)†
Sex, %
Male
Female
Dialect group, %
Cantonese
Hokkien
Level of Education, %
No formal schooling
Primary school
Secondary school or higher
Body mass index (kg/m2), mean (SD)
Alcohol consumption (drinks/wk), %
Non-drinkers
<7
≥7
Among drinkers, N
No. drinks/wk, mean (SD)
Green tea consumption, %
None
Monthly
Weekly
Daily
Black tea consumption, %
None
Monthly
Weekly
Daily
Smoking status, %
Never smokers
Former smokers
Current smokers
Among Ever Smokers, N
No. Cigarettes/day, mean (SD)
Number of years of smoking, mean (SD)
Age at starting to smoke, mean (SD)
History of diabetes, %
Negative
Positive / 11,342
56.7(8.4)
41.1
58.9
47.8
52.2
25.8
42.4
31.8
23.1 (3.3)
85.5
10.9
3.6
1,640
5.4 ± 9.0
58.3
9.3
15.8
16.5
61.5
5.1
13.3
20.0
77.7
10.8
11.4
1,298
15.3 (9.9)
36.9 (9.1)
20.3 (6.2)
88.9
11.1 / 6,807
56.1 (8.1)
46.0
54.0
47.0
53.0
22.7
41.2
36.0
23.3 (3.4)
81.5
15.2
3.4
1,262
4.3 ± 8.1
49.3
14.9
22.9
12.9
46.9
9.8
29.2
14.2
75.8
12.0
12.2
832
14.7 (9.7)
35.7 (9.3)
20.9 (6.2)
89.6
10.4 / 22,087
56.6 (8.0)
38.2
61.8
47.0
53.0
29.1
44.4
26.5
23.2 (3.2)
81.8
13.7
4.6
4,025
5.1 ± 8.6
58.2
11.9
17.6
12.4
66.3
8.1
16.4
9.2
73.5
10.2
16.4
3,615
14.6 (9.4)
36.4 (9.4)
20.6 (6.4)
90.9
9.1 / 21,085
56.1 (7.7)
52.4
47.6
44.2
55.8
27.3
46.5
26.2
23.0 (3.3)
77.5
16.6
6.0
4,744
5.4 ± 8.6
62.9
11.3
15.7
10.1
68.9
7.8
15.7
7.6
58.8
11.3
29.9
6,312
17.3 (10.2)
36.5 (8.9)
20.0 (6.1)
92.9
7.1 / <0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
0.039
<0.001
<0.001

*P values were derived from ANOVA or Chi-square tests.

† SD, standard deviation.