Table 2.
Associations of Coffee, Tea, or Caffeine Intake and Intraocular Pressure
| Difference in Intraocular Pressure (mmHg; 95% Confidence Interval) |
||||
|---|---|---|---|---|
| Variable | No. | Model 1* | Model 2† | Model 3‡ |
| Baseline | ||||
| Coffee intake (cups/day) | 121374 | −0.03 (−0.04 to −0.02) | −0.03 (−0.04 to −0.02) | −0.05 (−0.06 to −0.03) |
| Tea intake (cups/day) | 121374 | −0.04 (−0.05 to −0.03) | −0.03 (−0.04 to −0.02) | −0.04 (−0.06 to −0.03) |
| WebQ§ | ||||
| Coffee intake (cups/day) | 77906 | 0.01 (−0.03 to 0.04) | 0.00 (−0.03 to 0.03) | −0.02 (−0.06 to 0.01) |
| Tea intake (cups/day) | 77906 | −0.01 (−0.03 to 0.01) | 0.00 (−0.02 to 0.02) | −0.01 (−0.03 to 0.02) |
| Quintiles of total caffeine intake, mg/day | ||||
| 1 (0—<86.6) | 15581 | Reference | Reference | Reference |
| 2 (86.6—<139.1) | 15581 | 0.01 (−0.07 to 0.09) | −0.01 (−0.10 to 0.07) | −0.02 (−0.10 to 0.07) |
| 3 (139.1—<182.9) | 15 576 | 0.06 (−0.02 to 0.14) | 0.04 (−0.05 to 0.13) | 0.03 (−0.05 to 0.12) |
| 4 (182.9—<231.9) | 15 583 | −0.07 (−0.16 to 0.01) | −0.10 (−0.19 to −0.01) | −0.10 (−0.19 to −0.01) |
| 5 (≥231.9) | 15 585 | −0.12 (−0.21 to −0.04) | −0.09 (−0.18 to −0.004) | −0.10 (−0.19 to −0.01) |
| P value for trend|| | 0.001 | 0.01 | 0.01 | |
Adjusting for age (linear age in yrs), gender (male or female), and ethnicity (genetic White, self-reported Black, all others).
Model 1 with further adjustment for smoking status (never, past, or present), number of cigarettes (0 for never or past smokers, number of cigarettes smoked daily by current smokers), frequency of alcohol drinking (never or special occasion only, 1—3 times/mo, 1—2 times/wk, 3—4 times/wk, daily or almost daily), physical activity (metabolic equivalent of task [hr/wk]), deprivation index (linear score), BMI (kg/m2), systolic blood pressure (mmHg), and diabetes (yes/ no).
For coffee intake: model 2 with further adjustment for tea intake (cups/day). For tea intake: model 2 with further adjustment for coffee intake (cups/day).
For total caffeine intake: model 2 with further adjustment for total energy intake (kcal/day).
Web-based 24-hour diet questionnaire administered up to 4 times between February 2011 and June 2012.
Obtained from the P value of a continuous variable representing the median values of the quintile groups; the P value for trend provides a test of whether a linear association exists with increasing quintile of caffeine.