From: Cigarette smoking and smoking cessation in relation to risk of rheumatoid arthritis in women
 | Person-years1 | Cases, number1 | Age-adjusted relative risk | 95% CI | Multivariable relative risk2 | 95% CI |
---|---|---|---|---|---|---|
Never smokers | 137,162 | 79 | 1.00 (ref) | Â | 1.00 (ref) | Â |
Years since quitting | Â | Â | Â | Â | Â | Â |
1-14 | 23,297 | 20 | 1.45 | 0.88, 2.38 | 1.50 | 0.68, 3.30 |
≥ 15 (median 24) | 35,613 | 39 | 1.85 | 1.25, 2.73 | 1.99 | 1.23, 3.20 |
Age at quitting | Â | Â | Â | Â | Â | Â |
≤ 41 (median 32) | 31,164 | 31 | 1.68 | 1.09, 2.59 | 1.94 | 1.18, 3.18 |
> 41 (median 50) | 27,747 | 28 | 1.70 | 1.11, 2.62 | 2.02 | 1.01, 4.07 |