Table 1.
Characteristics of the Study Participants.
| Visit 1 | Visit 2 | Visit 3 | ||||
|---|---|---|---|---|---|---|
|
|
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| Characteristic | Total N | N (%) or Mean ± SD | Total N | N (%) or Mean ± SD | Total N | N (%) or Mean ± SD |
| Age, years | 63 | 61.6 ± 9.5 | ||||
| Sex | 63 | |||||
| Women | 48 (76.2) | |||||
| Men | 15 (23.8) | |||||
| Study eye | 63 | |||||
| Right | 35 (55.6) | |||||
| Left | 28 (44.4) | |||||
| CRAE, μm | 63 | 144.0 ± 13.7 | 63 | 144.6 ± 15.4 | 63 | 146.1 ± 15.6 |
| CRVE, μm | 63 | 213.7 ± 21.0 | 63 | 211.6 ± 21.8 | 63 | 213.8 ± 21.3 |
| Time of day examined | 63 | 63 | 63 | |||
| Before 10:00 AM | 19 (30.2) | 20 (31.8) | 21 (33.3) | |||
| Between 10:00 AM and noon | 15 (23.8) | 15 (23.8) | 14 (22.2) | |||
| Between noon and 2:00 PM | 17 (27.0) | 15 (23.8) | 16 (25.4) | |||
| After 2:00 PM | 12 (19.1) | 13 (20.6) | 12 (19.1) | |||
| Image focus quality | 63 | 63 | 63 | |||
| Excellent | 40 (63.5) | 37 (58.7) | 36 (58.1) | |||
| Good | 20 (31.8) | 22 (34.9) | 21 (33.9) | |||
| Fair or worse | 3 (4.8) | 4 (6.4) | 5 (8.1) | |||
| Systolic blood pressure, mmHg | 63 | 133.8 ± 18.7 | 63 | 134.1 ± 20.1 | 63 | 130.2 ± 18.2 |
| Diastolic blood pressure, mmHg | 63 | 78.9 ± 8.9 | 63 | 78.1 ± 9.8 | 63 | 77.1 ± 8.2 |
| Taking antihypertensive medication | 63 | 63 | 63 | |||
| No | 35 (55.6) | 35 (55.6) | 36 (57.1) | |||
| Yes | 28 (44.4) | 28 (44.4) | 27 (42.9) | |||
| Last used antihypertensive medication | 63 | 63 | 63 | |||
| Not taking | 35 (55.6) | 35 (55.6) | 36 (57.1) | |||
| <2 hours ago | 3 (4.8) | 5 (7.9) | 4 (6.4) | |||
| 2 to 12 hours ago | 22 (34.9) | 21 (33.3) | 20 (31.8) | |||
| >12 to 24 hours ago | 3 (4.8) | 1 (1.6) | 2 (3.2) | |||
| >24 hours ago | 0 (0.0) | 1 (1.6) | 1 (1.6) | |||
| Pulse rate, heartbeats per minute | 63 | 74.3 ± 12.4 | 63 | 75.2 ± 13.1 | 63 | 73.1 ± 11.8 |
| Blood oxygen level, % | 63 | 97.1 ± 1.7 | 63 | 97.6 ± 1.9 | 63 | 97.7 ± 1.8 |
| Time since last exercised | 63 | 63 | 63 | |||
| >12 hours | 40 (63.5) | 45 (71.4) | 44 (69.8) | |||
| 4 to 12 hours | 8 (12.7) | 5 (7.9) | 5 (7.9) | |||
| 2 to 3 hours | 3 (4.8) | 3 (4.8) | 3 (4.8) | |||
| < 2 hours | 3 (4.8) | 2 (3.2) | 3 (4.8) | |||
| Not sure | 9 (14.3) | 8 (12.7) | 8 (12.7) | |||
| Currently smoking | 63 | |||||
| No | 60 (95.2) | |||||
| Yes | 3 (4.8) | |||||
| Time since last smoked | 3 | 3 | 3 | |||
| >24 hours | 0 (0.0) | 1 (33.3) | 1 (33.3) | |||
| 12 to 24 hours | 0 (0.0) | 0 (0.0) | 0 (0.0) | |||
| 2 to 12 hours | 1 (33.3) | 1 (33.3) | 1 (33.3) | |||
| <2 hours | 2 (66.7) | 1 (33.3) | 1 (33.3) | |||
| Used caffeine in last 4 hours | 63 | 63 | 63 | |||
| No | 27 (42.9) | 29 (46.0) | 30 (47.6) | |||
| Yes | 36 (57.1) | 34 (54.0) | 33 (52.4) | |||
| Time since last using caffeine | 36 | 34 | 33 | |||
| < 1 hour | 10 (27.8) | 4 (11.8) | 6 (18.2) | |||
| 1 hour | 9 (25.0) | 10 (29.4) | 6 (18.2) | |||
| 2 hours | 10 (27.8) | 7 (20.6) | 9 (27.3) | |||
| 3 hours | 7 (19.4) | 9 (26.5) | 8 (24.2) | |||
| 4 hours | 0 (0.0) | 4 (11.8) | 4 (12.1) | |||
| Glaucoma present | 63 | |||||
| No | 59 (93.7) | |||||
| Yes | 4 (6.4) | |||||
| Using glaucoma drops | 63 | 63 | 63 | |||
| No | 60 (95.2) | 59 (93.7) | 59 (93.7) | |||
| Yes | 3 (4.8) | 4 (6.4) | 4 (6.4) | |||
| Time since last using glaucoma drops | 3 | 4 | 4 | |||
| <2 hours | 1 (33.3) | 2 (50.0) | 2 (50.0) | |||
| 2–12 hours | 2 (66.7) | 2 (50.0) | 2 (50.0) | |||
| >12 hours | 0 (0,0) | 0 (0,0) | 0 (0,0) | |||
| Time since last eating, hours | 63 | 5.2 ± 5.2 | 63 | 5.3 ± 5.4 | 63 | 4.7 ± 4.6 |
CRAE, central retinal arteriolar equivalent; CRVE, central retinal venular equivalent; SD, standard deviation.