Table 1 Baseline characteristics of patients with RA (cases, n = 2237) and controls (n = 4661) included in the EIRA study between 2005 and 2018, by categories of tea consumption
RA cases | Controls | |||||||
|---|---|---|---|---|---|---|---|---|
Tea, cups/day (median) | Non-consumers (0 cups/day) | Irregular consumers (< 1 cup/day) | Regular consumers (1–2 cups/day) | High consumers (≥2 cups/day) | Non-consumers (0 cups/day) | Irregular consumers (< 1 cup/day) | Regular consumers (1–2 cups/day) | High consumers (≥2 cups/day) |
Tea, median cups/day | 0 | 0.29 | 1 | 2 | 0 | 0.29 | 1 | 2.29 |
N | 955 | 453 | 388 | 441 | 1941 | 847 | 845 | 1028 |
Female, n (%) | 582 (60.94%) | 358 (79.03%) | 288 (74.23%) | 359 (81.41%) | 1255 (64.66%) | 643 (75.91%) | 622 (73.61%) | 817 (79.47%) |
Age, mean (std) | 56 (13) | 51 (15) | 56 (15) | 55 (14) | 55 (14) | 51 (14) | 56 (13) | 54 (14) |
Coffee, n (%) | ||||||||
0 cups/day | 70 (7.33) | 44 (9.71) | 43 (11.08) | 100 (22.68) | 172 (8.86) | 79 (9.33) | 83 (9.82) | 269 (26.17) |
≤2 cups/day | 243 (25.45) | 181 (39.96) | 163 (42.01) | 215 (48.75) | 529 (27.25) | 333 (39.32) | 373 (44.14) | 459 (44.65) |
2–3 cups/day | 222 (23.25) | 101 (22.30) | 85 (21.91) | 74 (16.78) | 479 (24.68) | 211 (24.91) | 204 (24.14) | 148 (14.40) |
> 3 cups/day | 420 (43.98) | 127 (28.04) | 97 (25.00) | 52 (11.79) | 761 (39.21) | 224 (26.45) | 185 (21.89) | 152 (14.79) |
Smoking, n (%) | ||||||||
Never | 290 (30.37) | 164 (36.20) | 142 (36.60) | 213 (48.30) | 859 (44.26) | 436 (51.48) | 433 (51.24) | 563 (54.77) |
Former | 310 (32.46) | 160 (35.32) | 145 (37.37) | 138 (31.29) | 564 (29.06) | 245 (28.93) | 257 (30.41) | 262 (25.49) |
Current < 20 pack-years | 130 (13.61) | 48 (10.60) | 29 (7.47) | 37 (8.39) | 173 (8.91) | 56 (6.61) | 41 (4.85) | 55 (5.35) |
Current ≥ 20 pack-years | 166 (17.38) | 41 (9.05) | 30 (7.73) | 22 (4.99) | 198 (10.20) | 40 (4.72) | 37 (4.38) | 44 (4.28) |
Education, n (%) | ||||||||
< 10 years | 253 (26.49%) | 83 (18.32%) | 66 (17.01%) | 61 (13.83%) | 401 (20.66%) | 87 (10.27%) | 123 (14.56%) | 93 (9.05%) |
10–12 years | 263 (27.54%) | 105 (23.18%) | 95 (24,48%) | 82 (18.59%) | 552 (28.44%) | 226 (26.68%) | 205 (24.26%) | 188 (18.29%) |
> 12 years | 439 (45.97%) | 265 (58.59%) | 227 (58.51%) | 298 (67.57%) | 988 (50.90%) | 534 (63.05%) | 517 (61.18%) | 747(72.67%) |
BMI, mean (std) | 26.19 (4.55) | 25.56 (4.91) | 25.46 (4.63) | 25.25 (4.39) | 25.83 (4.35) | 25.18 (4.42) | 25.29 (6.76) | 25.02 (4.26) |
Alcohol intake, mean grams/week (std) | 71.62 (101.94) | 57.70 (68.60) | 57.43 (70.53) | 55.68 (92.35) | 73.64 (95.06) | 75.13 (120.05) | 67.20 (75.58) | 59.08 (74.42) |