Table 1.
Comparison of Baseline Characteristics Between Participants and Eligible Non-Participants in the Study of Incidence of Age-Related Macular Degeneration (IAMD) of the Study of Osteoporotic Fractures (SOF).
| Characteristics | Participants (N=1958) | Non-participants† (N=294) | P-value‡ |
|---|---|---|---|
| Study Site | |||
| Baltimore, MD | 322 (16%) | 53 (18%) | 0.18 |
| Minneapolis, MN | 661 (34%) | 94 (32%) | |
| Pittsburgh, PA | 508 (26%) | 90 (31%) | |
| Portland, OR | 467 (24%) | 57 (19%) | |
| Age (years) | |||
| Mean±SD | 78.2±3.7 | 79.3±4.0 | |
| Median | 78.0 | 78.0 | 0.0002 |
| Race | |||
| White | 1713 (87%) | 262 (89%) | 0.43 |
| Black | 245 (13%) | 32 (11%) | |
| Education (years) | |||
| Mean±SD | 12.9±2.7 | 12.8±2.6 | |
| Median | 12.0 | 12.0 | 0.72 |
| <12 years | 338 (17%) | 52 (18%) | 0.86 |
| >=12 years (High School graduate or above) | 1619 (83%) | 242 (82%) | |
| Walks for exercise | |||
| Yes | 895 (46%) | 109 (37%) | 0.005 |
| No | 1056 (54%) | 184 (63%) | |
| Current smoker | |||
| Yes | 75 (4%) | 10 (3%) | 0.72 |
| No | 1881 (96%) | 284 (97%) | |
| Any alcohol in last 30 days | |||
| Yes | 942 (48%) | 118 (40%) | 0.010 |
| No | 1015 (52%) | 176 (60%) | |
| Self-rated health status | |||
| Good/Excellent | 1668 (85%) | 244 (83%) | 0.33 |
| Fair/Poor | 290 (15%) | 50 (17%) | |
| History of diabetes | |||
| Yes | 105 (5%) | 8 (3%) | 0.054 |
| No | 1853 (95%) | 285 (97%) | |
| History of hypertension | |||
| Yes | 706 (36%) | 106 (36%) | 1.00 |
| No | 1252 (64%) | 188 (64%) |
SD=Standard deviation
*
Subjects had gradable fundus photographs in at least one of the same eyes at both year 10 and year 15 clinic visits.
†
Eligible subjects did not have fundus photographs or had ungradable fundus photographs in both eyes at year 10 and/or at year 15 clinic visits.
‡
P-values are from Wilcoxon rank-sum tests for continuous variables and chi-square tests for categorical variables.