Number and proportion of RA cases attributable to selected risk factors in USA (2016), aged more than 15 years
| PAF (95% CI) | Cases | |
| Smoking | 14.00% (8.13% to 23.33%) | 16 072 |
| Excess BMI | 14.73% (5.45% to 23.50%) | 16 910 |
| Alcohol drinking | 8.21% (0.31% to 16.39%) | 9425 |
| Total | 32.69% (13.41% to 50.96%) | 37 528 |
BMI, body mass index; PAF, population attributable fraction; RA, rheumatoid arthritis.