Demographic characteristics and smoking history of patients with and without rheumatoid arthritis (RA)
| Non-cases* (N=48 919) | Cases (N=424) | ||||
|---|---|---|---|---|---|
| Characteristics | N (%) | N (%) | p Value† | ||
| Age (at interview), years | Median | Median | <0.0001 | ||
| 35–44 | 6459 (13) | 41 years | 27 (6) | 42 years | |
| 45–54 | 16 987 (35) | 50 | 117 (28) | 51 | |
| 55–64 | 17 108 (35) | 59 | 178 (42) | 59 | |
| ≥65 | 8361 (17) | 68 | 102 (24) | 68 | |
| Missing | 4 | 0 | |||
| Race/ethnicity | 0.04 | ||||
| Non-Hispanic white | 41 140 (84) | 342 (81) | |||
| Black | 4278 (9) | 41 (10) | |||
| Hispanic | 2214 (5) | 31 (7) | |||
| Other | 1272 (3) | 10 (2) | |||
| Missing | 15 | 0 | |||
| Current education | <0.0001 | ||||
| High school or less | 7339 (15) | 86 (20) | |||
| Some college/technical degree | 16 431 (34) | 168 (40) | |||
| College BA degree | 13 331 (27) | 86 (20) | |||
| Graduate or professional degree | 11 806 (24) | 84 (20) | |||
| Missing | 12 | 0 | |||
| Pack-years smoking | <0.0001 | ||||
| Never smoked | 26 451 (56) | 184 (45) | |||
| Smoked (quintiles pack-years) | |||||
| ≤2 | 4635 (10) | 39 (10) | |||
| 2–7 | 4338 (9) | 35 (9) | |||
| 7–14 | 3837 (8) | 41 (10) | |||
| 14–26 | 4160 (9) | 46 (11) | |||
| >26 | 4111 (9) | 50 (14) | |||
| Missing | 1387 | 19 | |||