Table 2 Selected descriptive characteristics of the study population
Cases (n = 238) | Controls (n = 832) | |
|---|---|---|
Mean (SD) | ||
Age (years)*** | 10.9 (3.1) | 13.4 (3.1) |
Age at diagnosis | 5.7 (3.7) | n/a |
N (%) | ||
Type of oligoarticular JIA: persistent | 196 (82.4) | n/a |
Sex: female*** | 170 (71.4) | 430 (51.7) |
Birth weight ≤ 2500 g | 34 (14.3) | 188 (22.6) |
Allergic rhinitis** | 22 (9.2) | 141 (16.9) |
Family history: | ||
At least 2 older siblings+ | 36 (15.5) | 137 (16.5) |
At least 2 younger siblings+ | 26 (11.0) | 112 (13.5) |
Parents with oligoarticular JIA+ | 5 (2.2) | n/a |
Day care attendance + | ||
Age 0-1 years | 15 (6.5) | 64 (7.7) |
Age 2-5 years | 187 (81.3) | 647 (78.0) |
Never | 28 (12.2) | 118 (14.2) |
Nutrition | ||
Breast feeding ≥6 months*** | 116 (48.7) | 250 (30.0) |
Nutritional supplements other than breast feeding <5 months *** #,+ | 138 (59.5) | 624 (76.1) |
Raw milk consumption during 1st year of life+ | 3 (1.3) | 23 (2.8) |
Maternal smoking during pregnancy* | 10 (4.2) | 67 (8.1) |
≥12 years of schooling+ | 99 (41.6) | 285 (34.3) |
Place of living | ||
City | 23 (9.7) | 88 (10.6) |
Rural town | 75 (31.5) | 255 (30.6) |
Village | 140 (58.8) | 489 (58.8) |
Regular & contact with pets | ||
ever | ||
Dogs | 93 (39.1) | 392 (47.1) |
Cats | 126 (52.9) | 422 (50.7) |
Cats or dogs | 157 (66.0) | 565 (67.9) |
Rabbits | 96 (40.3) | 327 (39.3) |
during 1 st year of life | ||
Dogs | 38 (16.0) | 166 (20.0) |
Cats | 45 (18.9) | 198 (23.8) |
Rabbits$ | 10 (4.2) | 65 (7.8) |
Cats, dogs or rabbits | 72 (30.3) | 295 (35.5) |
Living on a farm | ||
Now | 13 (5.5) | 37 (4.4) |
During 1st year of life | 14 (5.9) | 51 (6.1) |
Regular & contact with farm animals | ||
ever | ||
Cattle | 27 (11.3) | 96 (11.5) |
Pigs$ | 11 (4.6) | 65 (7.8) |
Sheep or goats | 10 (4.2) | 54 (6.5) |
during 1 st year of life | ||
Cattle | 15 (6.3) | 58 (7.0) |
Pigs* | 4 (1.7) | 37 (4.4) |
Sheep or goats | 3 (1.3) | 20 (2.4) |
Cattle, pigs, sheep or goats | 17 (7.1) | 75 (9.0) |