Table 10.
Comparison of the effects of smoking on all-cause and cause-specific mortality risk by location of recruitment to the RCGP Oral Contraception Study (N = 38 894)
| Cause of death | Number of cigarettes smoked daily at recruitment (location) | Number (%) of deaths | Unadjusted | Adjusteda | ||
|---|---|---|---|---|---|---|
| HR | 95% CI | HR | 95% CI | |||
| All causes | Non-smokers (all UK) | 2058 (10.7) | 1.00 | – | 1.00 | – |
| <15 (elsewhere in UK) | 1296 (14.0) | 1.47 | 1.37 to 1.58 | 1.53 | 1.46 to 1.61 | |
| ≥15 (elsewhere in UK) | 1420 (22.2) | 2.45 | 2.29 to 2.62 | 2.36 | 2.25 to 2.48 | |
| <15 (Scotland) | 211 (18.5) | 1.95 | 1.69 to 2.25 | 2.05 | 1.85 to 2.26 | |
| ≥15 (Scotland) | 238 (26.0) | 2.86 | 2.50 to 3.27 | 2.88 | 2.62 to 3.16 | |
| History of serious illnessb | – | – | – | 2.43 | 2.33 to 2.54 | |
| Contraceptive pill use statusb | – | – | – | 0.68 | 0.66 to 0.71 | |
| Parityb | – | – | – | 0.88 | 0.85 to 0.90 | |
| Social class | – | – | – | 0.79 | 0.75 to 0.82 | |
| Age | – | – | – | 1.069 | 1.066 to 1.072 | |
|
| ||||||
| Any cancers | Non-smokers (all UK) | 989 (4.7) | 1.00 | 1.00 | ||
| <15 (elsewhere in UK) | 524 (5.6) | 1.24 | 1.11 to 1.38 | 1.32 | 1.22 to 1.42 | |
| ≥15 (elsewhere in UK) | 615 (9.6) | 2.20 | 1.99 to 2.42 | 2.14 | 1.99 to 2.30 | |
| <15 (Scotland) | 97 (8.5) | 1.86 | 1.51 to 2.29 | 1.89 | 1.64 to 2.18 | |
| ≥15 (Scotland) | 99 (10.8) | 2.45 | 2.00 to 3.02 | 2.41 | 2.10 to 2.77 | |
|
| ||||||
| Circulatory disease | Non-smokers (all UK) | 510 (2.4) | 1.00 | 1.00 | ||
| <15 (elsewhere in UK) | 365 (3.9) | 1.67 | 1.46 to 1.91 | 1.78 | 1.61 to 1.96 | |
| ≥15 (elsewhere in UK) | 412 (6.4) | 2.87 | 2.52 to 3.27 | 2.77 | 2.51 to 3.05 | |
| <15 (Scotland) | 65 (5.7) | 2.43 | 1.88 to 3.14 | 2.72 | 2.27 to 3.25 | |
| ≥15 (Scotland) | 70 (7.6) | 3.40 | 2.65 to 4.37 | 3.50 | 2.94 to 4.18 | |
|
| ||||||
| Respiratory disease | Non-smokers (all UK) | 158 (0.7) | 1.00 | 1.00 | ||
| <15 (elsewhere in UK) | 152 (1.6) | 2.26 | 1.81 to 2.82 | 2.36 | 2.01 to 2.78 | |
| ≥15 (elsewhere in UK) | 184 (2.9) | 4.19 | 3.39 to 5.18 | 4.01 | 3.43 to 4.69 | |
| <15 (Scotland) | 11 (1.0) | 1.34 | 0.73 to 2.47 | 1.10 | 0.68 to 1.77 | |
| ≥15 (Scotland) | 33 (3.6) | 5.30 | 3.64 to 7.70 | 5.26 | 4.04 to 6.85 | |
|
| ||||||
| Other causes not specified | Non-smokers (all UK) | 401 (1.9) | 1.00 | 1.00 | ||
| <15 (elsewhere in UK) | 255 (2.7) | 1.49 | 1.27 to 1.74 | 1.49 | 1.32 to 1.68 | |
| ≥15 (elsewhere in UK) | 209 (3.3) | 1.84 | 1.56 to 2.18 | 1.76 | 1.55 to 2.01 | |
| <15 (Scotland) | 38 (3.3) | 1.80 | 1.29 to 2.52 | 2.03 | 1.60 to 2.58 | |
| ≥15 (Scotland) | 36 (3.9) | 2.22 | 1.58 to 3.12 | 2.44 | 1.91 to 3.12 | |
a
Adjusted for age and social class at recruitment and history of serious illness, contraceptive pill use status, and parity.
b
Entered as a time-dependent covariate. HR = hazard ratio.