Table 2.
Differences in Active Smoke Exposure Between Veterans and Non-Veterans in the Women’s Health Initiative Observational Study
| Non-Veteran | Veteran | Diff a | 95% CI | p Value | ||||
|---|---|---|---|---|---|---|---|---|
| N | Mean ( SD ) | N | Mean ( SD ) | LB | UB | |||
| Pack years of smoking | ||||||||
| Among all women | 79,767 | 9.88 (18.54) | 2,126 | 13.10 (21.53) | 2.54 | 1.68 | 3.40 | <.001 |
| Among former or current smokers | 38,135 | 20.67 (22.26) | 1,143 | 24.36 (24.25) | 2.12 | 0.78 | 3.46 | .002 |
| N | % | N | % | Difference in probability (percentage points) | ||||
| Diff a | 95% CI | p Value | ||||||
| LB | UB | |||||||
| Smoking status | ||||||||
| Never | 41,632 | 51.0 | 983 | 45.1 | −6.15 | −8.17 | −4.14 | <.001 |
| Former | 34,986 | 42.9 | 1,029 | 47.2 | 4.26 | 2.24 | 6.27 | <.001 |
| Current | 4,994 | 6.1 | 167 | 7.7 | 1.90 | 0.99 | 2.81 | <.001 |
| Pack years | ||||||||
| Never | 41,632 | 52.2 | 983 | 46.2 | −6.12 | −8.17 | −4.07 | <.001 |
| <5 | 11,876 | 14.9 | 293 | 13.8 | 0.227 | −1.35 | 1.81 | .78 |
| 5 to <20 | 11,445 | 14.3 | 319 | 15.0 | 1.23 | −0.24 | 2.69 | .10 |
| 20+ | 14,814 | 18.6 | 531 | 25.0 | 4.67 | 3.22 | 6.11 | <.001 |
| Initiating age (years) | ||||||||
| <15 | 2,615 | 6.6 | 75 | 6.3 | 0.95 | −0.50 | 2.40 | .20 |
| 15–19 | 20,049 | 50.3 | 493 | 41.3 | −5.38 | −8.30 | −2.45 | <.001 |
| 20–24 | 12,325 | 30.9 | 486 | 40.7 | 6.94 | 4.42 | 9.47 | <.001 |
| 25+ | 4,856 | 12.2 | 140 | 11.7 | −2.51 | −4.42 | −0.61 | .01 |
| Cessation age (years) | ||||||||
| <25 | 3,436 | 10.5 | 76 | 8.0 | −0.14 | −2.28 | 1.99 | .90 |
| 25–34 | 7,987 | 24.5 | 199 | 20.9 | −0.02 | −2.87 | 2.83 | .99 |
| 35–44 | 8,051 | 24.7 | 219 | 23.0 | −0.21 | −3.05 | 2.62 | .88 |
| 45–54 | 7,742 | 23.8 | 249 | 26.1 | 2.30 | −0.33 | 4.94 | .09 |
| 55+ | 5,354 | 16.4h8 | 211 | 22.1 | −1.92 | −3.90 | 0.05 | .06 |
Notes: CI = confidence interval; diff = difference; LB = lower bound; SD = standard deviation; UB = upper bound.
a Adjusted for age (continuous), region (nominal), years living with a smoker as a child (nominal), years living with a smoker as an adult (nominal), years working with a smoker (nominal); Veterans compared with non-Veterans.