The association between selected risk factors and sputum cytology in the baseline sample from the 1010 subjects who completed a full risk factor questionnaire, University of Colorado Lung Cancer Specialized Program of Research Excellence cohort, 1993–2001.
| Risk factor | Total sample na (%) | Sputum cytologyb | Odds ratios for moderate atypia or worse, compared to normal cytology | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Normal n (%) | Squamous metaplasia and mild atypia n (%) | Moderate atypia or worse n (%) | Crude odds ratio (95% confidence interval) | Multivariate-adjusted odds ratioc (95% confidence interval) | |||||
| All study subjects | 1005 (100) | 261 (26.0) | 602 (59.9) | 142 (14.1) | |||||
| Gender | |||||||||
| Female | 284 (28.3) | 77 (27.1) | 171 (60.2) | 36 (12.7) | 1.0 | 1.0 | |||
| Male | 721 (71.7) | 184 (25.5) | 431 (59.8) | 106 (14.7) | 1.23 (0.78–1.96) | 1.15 (0.69–1.91) | |||
| Age | |||||||||
| 30–59 years | 213 (21.2) | 41 (19.2) | 138 (64.8) | 34 (16.0) | 1.0 | 1.0 | |||
| 60–69 years | 378 (37.4) | 102 (27.1) | 231 (56.7) | 61 (16.2) | 0.72 (0.41–1.26) | 0.79 (0.44–1.44) | |||
| 70+ years | 416 (41.4) | 118 (28.4) | 251 (60.3) | 47 (11.3) | 0.48 (0.27–0.85) | 0.65 (0.35–1.22) | |||
| ptrend = 0.008 | ptrend = 0.27 | ||||||||
| Smoking status | |||||||||
| Former smoker | 701 (70.1) | 212 (30.3) | 406 (57.9) | 83 (11.8) | 1.0 | 1.0 | |||
| Current smoker | 299 (29.9) | 49 (16.4) | 191 (63.9) | 59 (19.7) | 3.08 (1.95–4.85) | 2.50 (1.52–4.13) | |||
| Use of vitamin supplements | |||||||||
| No | 372 (37.0) | 88 (23.6) | 222 (59.7) | 62 (16.7) | 1.0 | 1.0 | |||
| Yes | 633 (63.0) | 173 (27.3) | 380 (60.0) | 80 (12.7) | 0.65 (0.43–0.998) | 1.01 (0.63–1.61) | |||
| Use of NSAIDs | |||||||||
| No | 285 (28.4) | 86 (30.2) | 157 (55.1) | 42 (14.7) | 1.0 | 1.0 | |||
| Yes | 720 (71.6) | 175 (24.3) | 445 (61.8) | 100 (13.9) | 1.17 (0.75–1.82) | 1.15 (0.70–1.89) | |||
| Use of steroid inhalers | |||||||||
| No | 468 (46.6) | 129 (27.6) | 263 (56.2) | 76 (16.2) | 1.0 | 1.0 | |||
| Yes | 537 (53.4) | 132 (24.6) | 339 (63.1) | 66 (12.3) | 0.85 (0.56–1.28) | 1.16 (0.73–1.84) | |||
| Fruit and vegetable servings per month | |||||||||
| Quartile 1 (<47 servings) | 254 (25.6) | 57 (22.5) | 153 (60.2) | 44 (17.3) | 1.0 | 1.0 | |||
| Quartile 2 (47–74 servings) | 248 (25.1) | 62 (25.0) | 151 (60.9) | 35 (14.1) | 0.73 (0.41–1.30) | 1.02 (0.55–1.89) | |||
| Quartile 3 (75–110 servings) | 245 (24.8) | 68 (27.7) | 144 (58.8) | 33 (13.5) | 0.63 (0.36–1.11) | 0.84 (0.45–1.57) | |||
| Quartile 4 (≥111 servings) | 242 (24.5) | 70 (28.9) | 147 (60.8) | 25 (10.3) | 0.46 (0.25–0.85) | 0.60 (0.31–1.16) | |||
| ptrend = 0.01 | ptrend = 0.04 | ||||||||
a In some cases, total number is <1005 because of missing data.
b All P > 0.01 by χ2 across all categories except for age (P = 0.03) and smoking status (P < 0.0001).
c Adjusted for age (continuous), race, sex, current smoking status, enrollment date (continuous), FEVI (continuous), and fruit and vegetable servings (continuous).