Table 1.
Distributions of Baseline Characteristics among Study Participants by Diet Composite Dietary Antioxidant Index, the Singapore Chinese Health Study, 1993–2015
| Total # Subjects |
Composite Dietary Antioxidant Index in Quartile |
P-value | ||||
|---|---|---|---|---|---|---|
| Characteristics | Q1(−13.3, −4.9) | Q2(−4.9, −2.3) | Q3(−2.3, 1.0) | Q4(1.0, 58.6) | ||
|
| ||||||
| Number of subjects | 61,321 | 15,330 | 15,330 | 15,331 | 15,330 | |
| Mean age (±SD)a, year | 56.4 (8.0) | 58.6 (8.2) | 56.7 (7.9) | 55.6 (7.8) | 54.6 (7.5) | <0.001 |
| Sex (%) | ||||||
| Male | 27,293 (44.5) | 4,953 (32.3) | 6,091 (39.7) | 7,376 (48.1) | 8,873 (57.9) | <0.001 |
| Female | 34,028 (55.5) | 10,377 (67.7) | 9,239 (60.3) | 7,955 (51.9) | 6,457 (42.1) | |
| Dialect | ||||||
| Cantonese | 28,325 (46.2) | 5,571 (36.3) | 6,860 (44.8) | 7,626 (49.7) | 8,268 (53.9) | <0.001 |
| Hokkien | 32,996 (53.8) | 9,759 (63.7) | 8,470 (55.2) | 7,705 (50.3) | 7,062 (46.1) | |
| Highest level of education (%) | ||||||
| No formal education | 16,661 (27.2) | 6,592 (43.0) | 4,428 (28.9) | 3,284 (21.4) | 2,357 (15.4) | <0.001 |
| Primary school | 27,224 (44.4) | 6,269 (40.9) | 7,033 (45.9) | 7,164 (46.7) | 6,758 (44.1) | |
| Secondary school or higher | 17,436 (28.4) | 2,469 (16.1) | 3,869 (25.2) | 4,883 (31.9) | 6,215 (40.5) | |
| Mean BMI (±SD), Kg/m2 | 23.1(3.3) | 23.0 (3.2) | 23.1 (3.3) | 23.1 (3.3) | 23.2 (3.3) | 0.41 |
| Smoking status (%) | ||||||
| Never smoker | 42,583 (69.4) | 10,812 (70.5) | 10,913 (71.2) | 10,655 (69.5) | 10,203 (66.6) | <0.001 |
| Ever smoker | 18,738 (30.6) | 4,518 (29.5) | 4,417 (28.8) | 4,676 (30.5) | 5,127 (33.4) | |
| Alcohol consumption | ||||||
| Heavy drinker | 1,007 (1.6) | 195 (1.3) | 185 (1.2) | 257 (1.7) | 379 (2.4) | <0.001 |
| Non-heavy drinker | 60,314 (98.4) | 15,135 (98.7) | 15,145 (98.8) | 15,074 (98.3) | 14,960 (97.6) | |
| Weekly physical activityb | ||||||
| No | 41,083(67.0) | 11,920 (77.8) | 10,668 (69.6) | 9,726 (63.4) | 8,769 (57.2) | <0.001 |
| Yes | 20,238(33.0) | 3,410 (22.2) | 4,662 (30.4) | 5,605 (36.6) | 6,561 (42.8) | |
| Diabetes history (%) | ||||||
| No | 55,852 (91.1) | 13,764 (89.8) | 13,949 (91.0) | 14,055 (91.7) | 14,084 (91.9) | <0.001 |
| Yes | 5,469 (8.9) | 1,566 (10.2) | 1,381 (9.0) | 1,276 (8.3) | 1,246 (8.1) | |
| Family history of colorectal cancer (%) | ||||||
| No | 59,972 (97.8) | 15,082 (98.4) | 15,015 (98.0) | 14,960 (97.6) | 14,915 (97.3) | <0.001 |
| Yes | 1,349 (2.2) | 248 (1.6) | 315 (2.0) | 371 (2.4) | 415 (2.7) | |
| Any use of Supplement Antioxidant | ||||||
| No | 56,606(92.3) | 14,593(95.2) | 14,218(92.8) | 13,977(91.2) | 13,818(90.1) | <0.001 |
| Yes | 4,715(7.7) | 737(4.8) | 1,112(7.2) | 1,354(8.8) | 1,512(9.9) | |
| Mean energy intake (±SDa), Kcal/day | 1,556.6 (566.2) | 1008.1 (220.7) | 1,343.5 (223.3) | 1,646.6 (277.8) | 2,228.3 (548.8) | <0.001 |
a
BMI, body mass index; SD, standard deviation
b
see definition in the Methods