Table 2

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 factorTotal sample na (%)Sputum cytologybOdds 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 subjects1005 (100)261 (26.0)602 (59.9)142 (14.1)
Gender
 Female284 (28.3)77 (27.1)171 (60.2)36 (12.7)1.01.0
 Male721 (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 years213 (21.2)41 (19.2)138 (64.8)34 (16.0)1.01.0
 60–69 years378 (37.4)102 (27.1)231 (56.7)61 (16.2)0.72 (0.41–1.26)0.79 (0.44–1.44)
 70+ years416 (41.4)118 (28.4)251 (60.3)47 (11.3)0.48 (0.27–0.85)0.65 (0.35–1.22)
ptrend = 0.008ptrend = 0.27
Smoking status
 Former smoker701 (70.1)212 (30.3)406 (57.9)83 (11.8)1.01.0
 Current smoker299 (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
 No372 (37.0)88 (23.6)222 (59.7)62 (16.7)1.01.0
 Yes633 (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
 No285 (28.4)86 (30.2)157 (55.1)42 (14.7)1.01.0
 Yes720 (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
 No468 (46.6)129 (27.6)263 (56.2)76 (16.2)1.01.0
 Yes537 (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)1.01.0
 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 = 0.01ptrend = 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).