TABLE 2.
Association between ESRD incidence and the different types of caffeinated beverages in the Singapore Chinese Health Study1
| HR (95% CI)2 | ||||||
|---|---|---|---|---|---|---|
| Intake | Cases, n | Person-years | Model 1 | Model 2 | Model 3 | Model 4 |
| Coffee | ||||||
| None to <1 cup/d | 390 | 311,888 | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) |
| 1 cup/d | 419 | 383,245 | 0.85 (0.74, 0.98) | 0.85 (0.74, 0.97) | 0.91 (0.80, 1.05) | 0.91 (0.79, 1.05) |
| ≥2 cups/d | 334 | 366,016 | 0.70 (0.61, 0.81) | 0.70 (0.62, 0.82) | 0.83 (0.71, 0.96) | 0.82 (0.71, 0.96) |
| P-trend | <0.0001 | <0.0001 | 0.013 | 0.012 | ||
| Black tea | ||||||
| None to less than weekly | 828 | 759,127 | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) |
| Weekly to <1 cup/d | 190 | 182,607 | 1.04 (0.88, 1.22) | 1.04 (0.88, 1.22) | 1.04 (0.88, 1.22) | 1.02 (0.87, 1.20) |
| 1 cup/d | 93 | 87,682 | 1.06 (0.85, 1.31) | 1.07 (0.86, 1.33) | 1.06 (0.85, 1.31) | 1.02 (0.82, 1.27) |
| ≥2 cups/d | 32 | 31,734 | 0.94 (0.66, 1.35) | 0.95 (0.67, 1.36) | 0.92 (0.65, 1.31) | 0.88 (0.62, 1.26) |
| P-trend | 0.79 | 0.73 | 0.86 | 0.83 | ||
| Green tea | ||||||
| None to less than weekly | 783 | 748,722 | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) |
| Weekly to <1 cup/d | 199 | 182,640 | 1.12 (0.96, 1.31) | 1.09 (0.93, 1.27) | 0.96 (0.82, 1.12) | 0.95 (0.81, 1.11) |
| 1 cup/d | 156 | 124,025 | 1.26 (1.06, 1.50) | 1.18 (0.99, 1.40) | 1.02 (0.85, 1.21) | 1.01 (0.84, 1.20) |
| ≥2 cups/d | 5 | 5762 | 0.89 (0.37, 2.15) | 0.83 (0.34, 2.01) | 0.72 (0.30, 1.74) | 0.69 (0.28, 1.71) |
| P-trend | 0.01 | 0.09 | 0.85 | 0.71 | ||
| Soda | ||||||
| None to less than monthly | 923 | 799,752 | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) |
| Monthly to <1 glass/wk | 85 | 103,106 | 0.80 (0.64, 1.00) | 0.79 (0.63, 0.98) | 0.98 (0.78, 1.23) | 0.98 (0.78, 1.22) |
| Weekly to <1 glass/d | 104 | 124,297 | 0.85 (0.70, 1.05) | 0.84 (0.69, 1.03) | 1.04 (0.84, 1.28) | 1.04 (0.85, 1.28) |
| ≥1 glass/d | 31 | 33,994 | 0.91 (0.64, 1.31) | 0.92 (0.64, 1.32) | 1.08 (0.75, 1.55) | 1.08 (0.75, 1.55) |
| P-trend | 0.07 | 0.05 | 0.67 | 0.65 | ||
1 n = 63,147. The standard serving size of 1 cup or 1 glass was assigned as 237 mL. ESRD, end-stage renal disease; ref, reference.
2Model 1 adjusted for age at recruitment, sex, dialect group, year of recruitment, and education; model 2 adjusted for variables in model 1 plus BMI, smoking status, physical activity, alcohol consumption, red meat intake, and total protein intake; model 3 adjusted for all variables in model 2 plus self-reported history of diabetes, hypertension, stroke, and cardiovascular heart disease; model 4 adjusted for all variables in model 3 plus consumption of other caffeine-containing beverages (coffee, black tea, green tea, and soda).