Table 2.
Ever-, former-, current regular smoking and never-smoking at the time of pSS diagnosis date*
| Patients with pSS | Exposure | Risk estimate | N exposed (%)† | ||
|---|---|---|---|---|---|
| OR | 95% CI | Cases | Controls | ||
| All patients with pSS | Ever-smoker | 0.67 | (0.55 to 0.81) | 194 (37) | 1961 (44) |
| Former smoker | 0.81 | (0.65 to 1.00) | 154 (29) | 1244 (28) | |
| Current smoker | 0.37 | (0.26 to 0.53) | 38 (7) | 717 (16) | |
| Never-smoker | Ref. | 301 (57) | 2027 (46) | ||
| SSA- and/or SSB-positive pSS | Ever-smoker | 0.70 | (0.55 to 0.89) | 141 (38) | 1365 (44) |
| Former smoker | 0.82 | (0.63 to 1.06) | 109 (29) | 865 (28) | |
| Current smoker | 0.41 | (0.27 to 0.62) | 30 (8) | 500 (16) | |
| Never-smoker | Ref. | 208 (55) | 1429 (46) | ||
| SSA-/SSB-negative pSS | Ever-smoker | 0.58 | (0.40 to 0.85) | 52 (35) | 582 (45) |
| Former smoker | 0.77 | (0.51 to 1.17) | 44 (29) | 370 (29) | |
| Current smoker | 0.28 | (0.13 to 0.59) | 8 (5) | 212 (16) | |
| Never-smoker | Ref. | 90 (60) | 577 (45) | ||
*Intermittent smoking was not included in exposure variables; never-smokers were defined as individuals reporting having never smoked regularly or intermittently.
†
Sums of former and current smokers lower than number of ever-smokers relate to missing data/inconsistent reporting of respondents.
pSS, primary Sjögren’s syndrome; SSA, Ro/SSA autoantibodies; SSB, La/SSB autoantibodies; Ref., reference.