Table 1. Baseline Characteristics by Randomization Assignment.
| Variable | No. (%) | P value | |
|---|---|---|---|
| Standard treatment (n = 3918) | Intensive treatment (n = 3956) | ||
| Age, mean (SD), y | 67.6 (9.2) | 67.6 (9.2) | .88 |
| Female | 1385 (35.3) | 1430 (36.1) | .46 |
| Male | 2533 (64.7) | 2526 (63.9) | |
| Racea | |||
| Asian | 24 (0.6) | 21 (0.5) | .30 |
| Black | 1242 (31.7) | 1223 (30.9) | |
| Multiracial | 22 (0.6) | 21 (0.5) | |
| White | 2546 (65.0) | 2571 (65.0) | |
| Otherb | 84 (2.1) | 99 (2.5) | |
| Ethnicitya | |||
| Hispanic | 409 (10.4) | 424 (10.7) | .69 |
| Non-Hispanic | 3508 (89.6) | 3531 (89.3) | |
| Body mass index, mean (SD)c | 30.5 (5.7) | 30.7 (5.8) | .13 |
| Smoking | |||
| Never | 1742 (44.5) | 1755 (44.4) | .31 |
| Ever | 2140 (54.7) | 2154 (54.4) | |
| Physical vigorous activity | |||
| Rarely or never | 1008 (25.8) | 1035 (26.2) | .52 |
| 1-3 Times/mo | 661 (16.9) | 636 (16.1) | |
| 1 Time/wk | 409 (10.5) | 437 (11.1) | |
| 2-4 Times/wk | 1310 (33.5) | 1280 (32.5) | |
| >5 Times/wk | 518 (13.3) | 555 (14.1) | |
| Daily use of aspirin | 1957 (50.1) | 2034 (51.5) | .20 |
| Clinical or subclinical cardiovascular disease | 738 (18.8) | 768 (19.4) | .51 |
| Atrial fibrillation | 275 (7.0) | 299 (6.9) | >.99 |
| Congestive heart failure | 112 (2.9) | 124 (3.1) | .47 |
| Chronic kidney disease | 1036 (26.4) | 1099 (27.4) | .18 |
a
Self-reported race and ethnicity data were collected to assess representativeness of the general population and because of previously described differences in risks associated with conduction disease.
b
Other included Hawaiian or Pacific Islander, Native American, consolidated owing to small numbers.
c
Calculated as weight in kilograms divided by height in meters squared.