Table 3.
Hazard ratios (95% CIs) of incident herpes zoster according to smoking status: the cohort analysis
| Person-years | No. of incident cases | Incidence rate per 1000 person-years | Hazard ratio (95% CI) | P value | ||
|---|---|---|---|---|---|---|
| Age- and sex-adjusted | Multivariable- adjusted* | |||||
| Total subjects without past history of herpes zoster | ||||||
| Never smoker | 17 971 | 236 | 13·1 | 1·00 | 1·00 | |
| Former smoker | 6854 | 68 | 9·92 | 0·88 (0·60–1·28) | 0·87 (0·59–1·27) | 0·456 |
| Current smoker | 5886 | 31 | 5·27 | 0·51 (0·32–0·79) | 0·52 (0·33–0·81) | 0·004 |
| 1–19 | 2930 | 15 | 5·12 | 0·47 (0·27–0·83) | 0·48 (0·27–0·85) | 0·012 |
| ⩾20 | 2956 | 16 | 5·41 | 0·55 (0·31–0·98) | 0·56 (0·31–1·00) | 0·051 |
| Men | ||||||
| Never smoker | 2696 | 31 | 11·5 | 1·00 | 1·00 | |
| Former smoker | 6376 | 61 | 9·57 | 0·82 (0·53–1·26) | 0·82 (0·53–1·26) | 0·360 |
| Current smoker | 5247 | 27 | 5·15 | 0·49 (0·29–0·83) | 0·49 (0·29–0·83) | 0·008 |
| 1–19 | 2451 | 12 | 4·90 | 0·45 (0·23–0·87) | 0·45 (0·23–0·87) | 0·018 |
| ⩾20 | 2795 | 15 | 5·37 | 0·53 (0·28–1·00) | 0·54 (0·29–1·01) | 0·053 |
| Women | ||||||
| Never smoker | 15 276 | 205 | 13·4 | 1·00 | 1·00 | |
| Former smoker | 479 | 7 | 14·6 | 1·10 (0·52–2·34) | 1·12 (0·53–2·38) | 0·766 |
| Current smoker | 640 | 4 | 6·25 | 0·51 (0·19–1·36) | 0·52 (0·19–1·39) | 0·192 |
| 1–19 | 479 | 3 | 6·26 | 0·50 (0·16–1·56) | 0·51 (0·16–1·60) | 0·250 |
| ⩾20 | 161 | 1 | 6·21 | 0·52 (0·07–3·75) | 0·53 (0·07–3·80) | 0·528 |
*
Adjusted for age, sex, family history of herpes zoster and underlying diseases.