Table 3 Mortality hazard (HR) ratios and their 95% confidence intervals (CIs) comparing men who substituted spit tobacco use for cigarette smoking (“switchers”) with men who quit using tobacco use entirely (“quit entirely”) Cancer Prevention Study‐II, 1982–2002.
| Death cause (ICD‐9 codes)* | Tobacco use after smoking cessation | No of deaths | Death rate† | Age‐adjusted HR (95% CI)‡ | Multivariate‐adjusted HR (95% CI)§ | Multivariate‐adjusted HR (95% CI)¶ |
|---|---|---|---|---|---|---|
| All causes | Quit entirely | 23 358 | 1685 | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| Switcher | 895 | 1994 | 1.19 (1.12 to 1.28) | 1.13 (1.06 to 1.21) | 1.08 (1.01 to 1.15) | |
| Chew only | 620 | 1944 | 1.17 (1.08 to 1.26) | 1.12 (1.03 to 1.21) | 1.05 (0.97 to 1.14) | |
| Snuff only | 154 | 2112 | 1.25 (1.06 to 1.46) | 1.15 (0.98 to 1.35) | 1.11 (0.94 to 1.30) | |
| Chew and snuff | 121 | 2114 | 1.27 (1.06 to 1.52) | 1.17 (0.98 to 1.40) | 1.16 (0.97 t o 1.39) | |
| Lung cancer (162) | Quit entirely | 2384 | 128 | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| Switcher | 155 | 233 | 1.92 (1.63 to 2.26) | 1.76 (1.49 to 2.07) | 1.46 (1.24 to 1.73) | |
| Chew only | 103 | 218 | 1.79 (1.47 to 2.18) | 1.66 (1.36 to 2.02) | 1.34 (1.10 to 1.64) | |
| Snuff only | 31 | 283 | 2.28 (1.60 to 3.25) | 2.03 (1.42 to 2.91) | 1.75 (1.22 to 2.50) | |
| Chew and snuff | 21 | 248 | 2.19 (1.42 to 3.36) | 1.97 (1.28 to 3.03) | 1.87 (1.21 to 2.87) | |
| Coronary heart disease (410–414) | Quit entirely | 6075 | 386 | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| Switcher | 252 | 482 | 1.28 (1.13 to 1.45) | 1.19 (1.04 to 1.35) | 1.13 (1.00 to 1.29) | |
| Chew only | 185 | 498 | 1.33 (1.15 to 1.54) | 1.25 (1.08 to 1.45) | 1.18 (1.02 to 1.37) | |
| Snuff only | 41 | 492 | 1.29 (0.95 to 1.75) | 1.16 (0.85 to 1.58) | 1.12 (0.82 to 1.53) | |
| Chew and snuff | 26 | 369 | 1.02 (0.70 to 1.51) | 0.90 (0.61 to 1.33) | 0.89 (0.60 to 1.31) | |
| Stroke (430–438) | Quit entirely | 2336 | 123 | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| Switcher | 93 | 151 | 1.29 (1.05 to 1.59) | 1.28 (1.04 to 1.58) | 1.24 (1.01 to 1.53) | |
| Chew only | 66 | 151 | 1.28 (1.00 to 1.63) | 1.27 (0.99 to 1.63) | 1.23 (0.96 to 1.57) | |
| Snuff only | 11 | 112 | 0.94 (0.52 to 1.69) | 0.92 (0.51 to 1.66) | 0.89 (0.49 to 1.62) | |
| Chew and snuff | 16 | 196 | 1.87 (1.14 to 3.05) | 1.81 (1.11 to 2.97) | 1.80 (1.10 to 2.95) | |
| COPD (490–492, 496) | Quit entirely | 878 | 49 | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| Switcher | 44 | 84 | 1.74 (1.29 to 2.36) | 1.53 (1.13 to 2.08) | 1.31 (0.96 to 1.78) | |
| Chew only | 32 | 86 | 1.75 (1.23 to 2.50) | 1.53 (1.07 to 2.18) | 1.26 (0.88 to 1.80) | |
| Snuff only | 9 | 92 | 2.19 (1.14 to 4.23) | 1.94 (1.00 to 3.75) | 1.68 (0.87 to 3.26) | |
| Chew and snuff | 3 | 63 | 1.03 (0.33 to 3.19) | 0.89 (0.29 to 2.78) | 0.91 (0.29 to 2.84) |
COPD, chronic obstructive pulmonary disease; ICD‐9, International Classification of Diseases—ninth edition.
*Analysis for all causes excluded men who reported a history of cancer, heart disease, diabetes, stroke, chronic bronchitis or emphysema in 1982 (28%); analysis for lung cancer excluded men who reported a history of any cancer except non‐melanoma skin cancer in 1982 (6%); analysis for coronary heart disease excluded men who reported a history of heart disease or diabetes in 1982 (19%); analysis for stroke excluded men who reported a history of stroke in 1982 (2%); analysis for COPD excluded men who reported a history of chronic bronchitis or emphysema in 1982 (6%). “Chew and snuff” includes men who currently use both chewing tobacco and snuff, and men who currently use only one product and reported past use of the other product.
†Death rates are per 100 000 person‐years and are age‐standardised to the Cancer Prevention Study‐II male person‐year distribution.
‡From Cox proportional hazards models, adjusted for age only.
§From Cox proportional hazards models adjusted for age, race, educational level, body mass index, exercise level, alcohol consumption, employment type, employment status, fat consumption, fruit and vegetable intake and aspirin use.
¶From Cox proportional hazards models adjusted for age, number of cigarettes formerly smoked per day, number of years smoked cigarettes, age at which they quit smoking cigarettes, race, educational level, body mass index, exercise level, alcohol consumption, employment type, employment status, fat consumption, fruit and vegetable intake and aspirin use.