Table 1. Baseline Characteristics of Participants.
| Characteristics | Participants, No. (%) |
|---|---|
| Total | 4751 |
| Age, mean (SD), y | 69.4 (5.1) |
| Sex | |
| Male | 2096 (44.1) |
| Female | 2655 (55.9) |
| Race/ethnicity | |
| White, non-Hispanic | 4543 (95.6) |
| Black, non-Hispanic | 177 (3.7) |
| Hispanic | 13 (0.3) |
| Asian or Pacific Islander | 8 (0.2) |
| Other | 10 (0.2) |
| Educational attainment | |
| ≤High school | 1708 (36.0) |
| Some college | 1409 (29.7) |
| College graduate | 1634 (34.4) |
| Smoking status | |
| Never | 2105 (44.3) |
| Former | 2271 (47.8) |
| Current | 375 (7.9) |
| BMI | |
| ≤25.0 | 1550 (32.6) |
| >25.0 and ≤30 | 1984 (41.8) |
| >30.0 | 1217 (25.6) |
| Diabetes mellitus | |
| Yes | 398 (8.4) |
| No | 4353 (91.6) |
| Age-Related Eye Disease Study treatment assignment | |
| Placebo | 1480 (31.2) |
| Antioxidants | 1481 (31.2) |
| Zinc | 902 (19.0) |
| Antioxidants plus zinc | 888 (18.7) |
| Antacid use | |
| Absent | 3962 (83.4) |
| Present | 789 (16.6) |
| Nonsteroidal anti-inflammatory drug use | |
| Absent | 3211 (67.6) |
| Present | 1540 (32.4) |
| Calcium use | |
| No | 4064 (85.5) |
| Yes | 687 (14.5) |
| Supplementary calcium-intake tertilesa | |
| No calcium use | 4064 (85.5) |
| 1 (Lowest) | 277 (5.8) |
| 2 | 133 (2.8) |
| 3 (Highest) | 277 (5.8) |
| Dietary calcium-intake quintilesa | |
| Missing | 6 (0.1) |
| 1 (Lowest) | 949 (20.0) |
| 2 | 950 (20.0) |
| 3 | 949 (20.0) |
| 4 | 949 (20.0) |
| 5 (Highest) | 948 (20.0) |
Abbreviation: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared).
a
Numbers in each quintile and tertile include all Age-Related Eye Disease Study participants (N = 4751), and they differ in size from the calorie restriction–defined groups included in disease outcome statistics.