Table 3.
Atopic and autoimmune conditions and risk of hairy cell leukemia (“basic model”)*
| Controls, N (%) | Cases, N (%) | OR (95% CI)† | P | |
|---|---|---|---|---|
| Any atopic disorder‡,§ | ||||
| No | 5515 (62.4) | 98 (63.6) | 1.00 (referent) | .925 |
| Yes | 3286 (37.2) | 56 (36.4) | 1.02 (0.72 to 1.44) | |
| Allergy§,|| | ||||
| No | 6614 (74.9) | 115 (74.7) | 1.00 (referent) | .579 |
| Yes | 2144 (24.3) | 39 (25.3) | 1.12 (0.76 to 1.65) | |
| Food allergy§ | ||||
| No | 8119 (91.9) | 145 (94.2) | 1.00 (referent) | .628 |
| Yes | 544 (6.2) | 9 (5.8) | 1.19 (0.59 to 2.40) | |
| Asthma§ | ||||
| No | 7411 (83.9) | 134 (87.0) | 1.00 (referent) | .569 |
| Yes | 689 (7.8) | 14 (9.1) | 1.18 (0.67 to 2.09) | |
| Hay fever§ | ||||
| No | 6043 (68.4) | 111 (72.1) | 1.00 (referent) | .278 |
| Yes | 1549 (17.5) | 34 (22.1) | 1.26 (0.84 to 1.89) | |
| History of autoimmune disease¶ | ||||
| No autoimmune disease | 8356 (94.6) | 142 (92.2) | 1.00 (referent) | .835 |
| B-cell activation | 87 (1.0) | 2 (1.3) | 1.33 (0.32 to 5.58) | |
| T-cell activation | 387 (4.4) | 10 (6.5) | 1.29 (0.67 to 2.49) | |
| Both | 4 (0.0) | 0 (0.0) | ||
* CI = confidence interval; OR = odds ratio.
† OR (95% CI) adjusted for age, sex, race/ethnicity, and study.
‡ Atopic disorders include asthma, eczema, hay fever, or other allergies, excluding drug allergies.
§ The counts do not add up to the total number of cases/controls due to data missing by design or report.
|| History of allergy excludes drug allergies, asthma, eczema, and hay fever.
¶ Includes self-reported history of specific autoimmune diseases occurring ≥2 y before diagnosis/interview (except the New South Wales study, which did not ascertain date of onset). Autoimmune diseases were classified according to whether they are primarily mediated by B-cell or T-cell responses. B-cell–activating diseases included Hashimoto thyroiditis, hemolytic anemia, myasthenia gravis, pernicious anemia, rheumatoid arthritis, Sjögren’s syndrome, and systemic lupus erythematosus. T-cell–activating diseases included celiac disease, immune thrombocytopenic purpura, inflammatory bowel disorder (Crohn’s disease, ulcerative colitis), multiple sclerosis, polymyositis or dermatomyositis, psoriasis, sarcoidosis, systemic sclerosis scleroderma, and type 1 diabetes.