Table 1.
Characteristics by Coffee and Tea Consumption Status among UK Biobank Participants with Intraocular Pressure Measurements and Coffee and Tea Data at Baseline (n = 121374)
| Coffee Consumption |
Tea Consumption |
|||||
|---|---|---|---|---|---|---|
| Variable | Nondrinkers, 0 Cups/Day (n = 26967) | Low Consumption, ≤1 Cup/Day (n = 34726) | High Consumption, >1 Cup/Day (n = 59681) | Nondrinkers, 0 Cups/Day (n = 17244) | Low Consumption, ≤ 3 Cups/Day (n = 49980) | High Consumption, >3 Cups/Day (n = 54150) |
| Age (yrs), mean (SD) | 55.6 (8.2) | 57.2 (8.0) | 57.2 (7.9) | 55.9 (8.2) | 56.6 (8.2) | 57.4 (7.8) |
| Gender, no. (%) | ||||||
| Male | 11376 (42.2) | 15390 (44.3) | 29314 (49.1) | 7546 (43.8) | 23341 (46.7) | 25193 (46.5) |
| Female | 15591 (57.8) | 19336 (55.7) | 30367 (50.9) | 9698 (56.2) | 26 639 (53.3) | 28 957 (53.5) |
| Ethnicity, no. (%)* | ||||||
| White (genetically) | 18607 (69.3) | 26091 (75.5) | 47979 (80.7) | 13324 (77.6) | 35551 (71.5) | 43802 (81.2) |
| Black (self-report) | 367 (1.4) | 412 (1.2) | 383 (0.6) | 121 (0.7) | 686 (1.4) | 355 (0.7) |
| Other | 7861 (29.3) | 8076 (23.4) | 11070 (18.6) | 3726 (21.7) | 13490 (27.1) | 9791 (18.1) |
| Smoking status, no. (%) | ||||||
| Never | 16308 (60.7) | 20221 (58.4) | 30919 (52.0) | 9211 (53.5) | 28431 (57.1) | 29814 (55.2) |
| Past | 8270 (30.8) | 11828 (34.2) | 21782 (36.6) | 5918 (34.4) | 17111 (34.3) | 18884 (35.0) |
| Current | 2290 (8.5) | 2560 (7.4) | 6766 (11.4) | 2074 (12.1) | 4274 (8.6) | 5270 (9.8) |
| Alcohol drinking frequency, no. (%) | ||||||
| Never or special occasions only | 8928 (33.1) | 6761 (19.5) | 9447 (15.8) | 4295 (24.9) | 9689 (19.4) | 11152 (20.6) |
| At least once per month | 18017 (66.9) | 27948 (80.5) | 50188 (84.2) | 12940 (75.1) | 40253 (80.6) | 42960 (79.4) |
| Physical activity (MET hr/wk), mean (SD) | 44.9 (46.5) | 43.6 (42.8) | 43.7 (44.0) | 44.0 (46.0) | 41.8 (41.7) | 45.9 (45.8) |
| BMI (kg/m2), mean (SD) | 27.4 (4.7) | 27.0 (4.5) | 27.4 (4.5) | 27.9 (4.9) | 27.1 (4.5) | 27.2 (4.4) |
| SBP (mmHg), mean (SD) | 136.6 (18.6) | 137.4 (18.5) | 137.7 (18.1) | 136.8 (18.3) | 137.2 (18.3) | 137.7 (18.4) |
| Diabetes (yes), no. (%) | 1797 (6.7) | 2002 (5.8) | 3450 (5.8) | 1234 (7.2) | 3080 (6.2) | 2935 (5.4) |
| Deprivation index, mean (SD)† | −0.6 (3.1) | −1.1 (3.0) | −1.3 (2.9) | −0.9 (3.1) | −1.0 (3.0) | −1.2 (2.9) |
| Coffee intake (cups/day), mean (SD) | 0.0 | 0.9 (0.2) | 3.3 (1.4) | 3.1 (2.1) | 2.1 (1.6) | 1.3 (1.5) |
| Coffee type, no. (%) | ||||||
| Noncoffee drinker | 26967 (100.0) | 0 (0.0) | 0 (0.0) | 2856 (16.6) | 7860 (15.8) | 16251 (30.2) |
| Decaffeinated | 0 (0.0) | 6354 (18.5) | 11090 (18.7) | 2809 (16.4) | 7267 (14.6) | 7368 (13.7) |
| Instant | 0 (0.0) | 17086 (49.7) | 33566 (56.6) | 8372 (48.8) | 21894 (44.1) | 20386 (37.9) |
| Ground | 0 (0.0) | 9868 (28.7) | 13865 (23.4) | 2898 (16.9) | 11791 (23.8) | 9044 (16.8) |
| Others | 0 (0.0) | 1050 (3.1) | 785 (1.3) | 237 (1.4) | 806 (1.6) | 792 (1.5) |
| Tea intake (cups/day), mean (SD) | 3.8 (2.0) | 3.7 (1.8) | 2.5 (2.0) | 0.0 | 2.0 (0.9) | 5.1 (0.9) |
| Total caffeine intake (mg/day), mean (SD)‡ | 8.9 (27.8) | 49.1 (48.9) | 135.3 (89.0) | 2.9 (13.7) | 49.8 (38.2) | 114.1 (57.1) |
| Quintiles of total caffeine intake, no. (%)‡,|| | ||||||
| Quintile 1 | 5851 (36.7) | 4924 (21.8) | 4807 (12.2) | 3847 (34.6) | 7725 (23.7) | 4010 (11.7) |
| Quintile 2 | 2871 (18.0) | 4479 (19.8) | 4219 (10.7) | 1340 (12.1) | 6288 (19.3) | 3941 (11.5) |
| Quintile 3 | 4409 (27.7) | 6758 (29.9) | 8420 (21.4) | 1898 (17.1) | 7468 (22.9) | 10221 (29.9) |
| Quintile 4 | 2431 (15.3) | 4251 (18.8) | 8901 (22.6) | 1794 (16.2) | 5308 (16.3) | 8481 (24.8) |
| Quintile 5 | 374 (2.3) | 2157 (9.6) | 13054 (33.1) | 2226 (20.0) | 5802 (17.8) | 7557 (22.1) |
| Total energy intake (kcal/day), mean (SD)‡ | 2059.4 (809.5) | 2088.4 (749.3) | 2138.6 (751.2) | 2069.6 (836.0) | 2091.3 (739.2) | 2135.5 (761.3) |
| IOP (mmHg), mean (SD) | 15.8 (3.8) | 16.1 (3.8) | 16.0 (3.8) | 15.9 (3.8) | 16.1 (3.8) | 15.9 (3.8) |
| IOP polygenic risk score, mean (SD)¶ | 0.05 (1.0) | 0.02 (1.0) | −0.0002 (1.0) | 0.02 (1.0) | 0.03 (1.0) | 0.005 (1.0) |
BMI = body mass index; IOP = intraocular pressure; MET = metabolic equivalent of task; SBP = systolic blood pressure; SD = standard deviation.
For Whites, ethnicity is based on principal component analysis. For other ethnicities, it is based on self-report.26
Unit was 1 unit of the Townsend deprivation index (a composite measure of deprivation based on unemployment, noncar ownership, nonhome ownership, and household overcrowding; a lower value represents higher socioeconomic status).
Data on total caffeine intake and total energy intake was from 77 906 participants who completed the WebQ (web-based 24-hour diet questionnaire administered up to 4 times between February 2011 and June 2012).
Cutoffs of caffeine (milligrams per day) quintiles among WebQ (web-based 24-hour diet questionnaire administered up to 4 times between February 2011 and June 2012) responders (n = 77 906): twentieth percentile, 86.7; fortieth percentile, 139.1; sixtieth percentile, 182.9; and eightieth percentile, 231.9.
The IOP polygenic risk score was normalized so that the mean was 0 and the SD was 1. Data on the IOP polygenic risk score are from the 117 458 participants with genetic data.