Table 1.
Baseline Characteristics of the 25 871 VITAL Participants, According to Randomized Treatment Assignment a .
| Baseline characteristics b | All participants | Vitamin D | n-3 fatty acids | ||
|---|---|---|---|---|---|
| Active | Placebo | Active | Placebo | ||
| Total number | 25 871 | 12 927 | 12 944 | 12 933 | 12 938 |
| Female sex, n (%) | 13 085/25 871 (50.6) | 6547 (50.6) | 6538 (50.5) | 6547 (50.6) | 6538 (50.5) |
| Age, years, mean ± SD | 67.1 ± 7.1 | 67.1 ± 7.0 | 67.1 ± 7.1 | 67.2 ± 7.1 | 67.1 ± 7.1 |
| Race/ethnicity, n (%) c | |||||
| Non-Hispanic White | 18 046/25 304 (71.3) | 9013 (71.3) | 9033 (71.4) | 9044 (71.5) | 9002 (71.2) |
| African American | 5106/25 304 (20.2) | 2553 (20.2) | 2553 (20.2) | 2549 (20.1) | 2557 (20.2) |
| Hispanic (not African American) | 1013/25 304 (4.0) | 516 (4.1) | 497 (3.9) | 491 (3.9) | 522 (4.1) |
| Asian/Pacific Islander | 388/25 304 (1.5) | 188 (1.5) | 200 (1.6) | 200 (1.6) | 188 (1.5) |
| Native American | 228/25 304 (0.9) | 118 (0.9) | 110 (0.9) | 120 (0.9) | 108 (0.9) |
| Other or unknown | 523/25 304 (2.1) | 259 (2.0) | 264 (2.1) | 249 (2.0) | 274 (2.2) |
| Body mass index, kg/m2, mean ± SD d | 28.1 ± 5.7 | 28.1 ± 5.7 | 28.1 ± 5.7 | 28.1 ± 5.7 | 28.1 ± 5.8 |
| Current smoking, n (%) | 1836/25 485 (7.2) | 921 (7.2) | 915 (7.2) | 920 (7.2) | 916 (7.2) |
| Hypertension treated with medication, n (%) | 12 791/25 698 (49.8) | 6352 (49.5) | 6439 (50.1) | 6338 (49.3) | 6453 (50.2) |
| Cholesterol-lowering medication, current use, n (%) | 9524/25 428 (37.5) | 4822 (38.0) | 4702 (36.9) | 4788 (37.7) | 4736 (37.2) |
| Diabetes, n (%) | 3549/25 828 (13.7) | 1812 (14.0) | 1737 (13.4) | 1799 (13.9) | 1750 (13.5) |
| Current regular aspirin use, n (%) e | 11 570/25 497 (45.4) | 5756 (45.2) | 5814 (45.6) | 5771 (45.3) | 5799 (45.5) |
Abbreviation: SD, standard deviation.
b
There were no significant differences in the baseline characteristics between the groups.
c
Race and ethnic group were reported by participants.
d
For body mass index, data were missing for 2.4% of participants.
e
At least monthly.