From: Investigation of the association between coffee and risk of RA—results from the Swedish EIRA study
RA cases | Controls | |||||||
---|---|---|---|---|---|---|---|---|
Coffee, cups/day | < 2 cups/day | 2–< 4 cup/day | 4–< 6 cups/day | ≥ 6 cups/day | < 2 cups/day | 2–< 4 cup/day | 4–< 6 cups/day | ≥ 6 cups/day |
Coffee, median cups/day | 0.4 | 2.5 | 4.0 | 7.0 | 0.3 | 2.4 | 4.0 | 6.4 |
N | 571 | 947 | 483 | 183 | 1164 | 1874 | 907 | 256 |
Female, n (%) | 445 (78) | 684 (72) | 327 (68) | 105 (57) | 894 (77) | 1401 (75) | 573 (63) | 136 (53) |
Age, mean (SD) | 49.8 (16.7) | 56.4 (13.0) | 56.4 (11.1) | 55.5 (9.7) | 51.1 (16.0) | 56.6 (13.0) | 56.2 (11.3) | 55.2 (11.4) |
Tea, n (%) | ||||||||
0 cups/day | 149 (26) | 377 (40) | 289 (60) | 120 (66) | 309 (27) | 765 (41) | 505 (56) | 182 (71) |
≤ 2 cups/day | 116 (20) | 211 (22) | 84 (17) | 35 (19) | 198 (17) | 368 (20) | 155 (17) | 34 (13) |
2–3 cups/day | 110 (19) | 175 (19) | 73 (15) | 16 (9) | 219 (19) | 376 (20) | 137 (15) | 23 (9) |
> 3 cups/day | 196 (34) | 184 (19) | 37 (8) | 12 (7) | 438 (38) | 365 (20) | 110 (12) | 17 (7) |
Smoking, n (%) | ||||||||
Current | 68 (12) | 168 (18) | 159 (33) | 87 (48) | 76 (7) | 207 (11) | 196 (22) | 94 (37) |
Never | 297 (52) | 338 (36) | 106 (22) | 34 (19) | 689 (59) | 946 (51) | 360 (40) | 75 (29) |
Former | 145 (25) | 347 (37) | 174 (36) | 52 (28) | 264 (23) | 536 (29) | 272 (30) | 61 (24) |
Non-regular | 43 (8) | 62 (7) | 27 (6) | 3 (2) | 83 (7) | 117 (6) | 39 (4) | 13 (5) |
Other | 20 (2) | 25 (3) | 11 (2) | 6 (3) | 29 (3) | 47 (3) | 29 (3) | 10 (4) |
Education, n (%) | ||||||||
< 10 years | 95 (17) | 187 (20) | 121 (25) | 47 (26) | 133 (11) | 284 (15) | 174 (19) | 55 (22) |
10–12 years | 166 (29) | 201 (21) | 111 (23) | 58 (32) | 298 (26) | 443 (24) | 243 (27) | 79 (31) |
> 12 years | 310 (54) | 559 (59) | 251 (52) | 78 (43) | 722 (63) | 1147 (61) | 490 (54) | 122 (48) |
BMI, mean (SD) | 25.7 (5.1) | 25.8 (4.6) | 25.8 (4.4) | 26.0 (4.4) | 25.3 (4.7) | 25.3 (5.5) | 25.6 (4.0) | 25.9 (3.9) |
Alcohol intake, median grams/week (IQR) | 29.0 (61) | 38.0 (69.8) | 41.0 (72.0) | 41.5 (63.3) | 29.0 (70.0) | 47.0 (76.0) | 48.0 (79.0) | 43.5 (93.0) |