Table 3. Association between main hormonal factors and lung cancer risk.
| Hormonal factor | Cases | Controls | OR | 95% CI | pa |
|---|---|---|---|---|---|
|
OC | |||||
| Never | 818 | 1020 | 1 | ||
| Ever | 958 | 1322 | 0.81 | (0.68––0.97) | 0.02 |
| Missing |
185 |
267 |
|
|
|
|
OC duration | |||||
| Never users | 818 | 1020 | 1 | ||
| ⩽1 year | 262 | 316 | 0.85 | (0.67–1.09) | |
| 1–5 years | 287 | 421 | 0.81 | (0.65–1.03) | |
| 5–10 years | 230 | 330 | 0.78 | (0.61–1.00) | |
| >10 years | 156 | 238 | 0.70 | (0.53–0.93) | 0.007 |
| Missing |
208 |
284 |
|
|
0.2b |
|
HRTc | |||||
| Never | 1078 | 1094 | 1 | ||
| Ever | 699 | 995 | 0.77 | (0.66–0.90) | 0.001 |
| Missing |
15 |
4 |
|
|
|
|
HRT durationc | |||||
| Never users | 1078 | 1094 | 1 | ||
| ⩽2 years | 157 | 257 | 0.61 | (0.47–0.78) | |
| 2–7 years | 166 | 227 | 0.84 | (0.65–1.09) | |
| 7–14 years | 156 | 220 | 0.79 | (0.60–1.03) | |
| >14 years | 142 | 209 | 0.70 | (0.53–0.92) | 0.004 |
| Missing |
93 |
86 |
|
|
0.7b |
|
HRT typed | |||||
| Never users | 676 | 685 | 1 | ||
| Oetrogen Only | 271 | 397 | 0.76 | (0.61–0.94) | 0.01 |
| E+P only | 138 | 237 | 0.66 | (0.49–0.88) | 0.005 |
| Missing |
120 |
119 |
|
|
|
|
HRT type-specific durationd | |||||
|
Oestrogen only | |||||
| Never users | 676 | 685 | 1 | ||
| ⩽2 years | 67 | 101 | 0.67 | (0.47–0.98) | |
| 2–8 years | 66 | 92 | 0.81 | (0.56–1.19) | |
| 8–16 years | 61 | 91 | 0.80 | (0.54–1.18) | |
| >16 years | 70 | 105 | 0.71 | (0.49–1.02) | 0.03 |
| |
|
|
|
|
0.9b |
|
E+P only | |||||
| Never users | 676 | 685 | 1 | ||
| ⩽2 years | 30 | 60 | 0.55 | (0.33–0.93) | |
| 2–5 years | 35 | 60 | 0.69 | (0.41–1.16) | |
| 5–10 years | 32 | 67 | 0.52 | (0.31–0.87) | |
| >10 years | 39 | 47 | 0.94 | (0.56–1.57) | 0.04 |
| |
|
|
|
|
0.5b |
|
OC/HRT combinedc | |||||
| OC never/HRT never | 539 | 552 | 1 | ||
| OC ever/HRT never | 426 | 390 | 0.80 | (0.62–1.03) | 0.09 |
| OC never/HRT ever | 224 | 327 | 0.74 | (0.57–0.96) | 0.02 |
| OC ever/HRT ever | 417 | 566 | 0.61 | (0.47–0.78) | <0.001 |
| Missing | 186 | 258 | |||
Abbreviations: CI=confidence interval; E+P=oestrogen+progesterone; HRT=hormone replacement therapy; OC=oral contraceptive; OR=odds ratio.
Effect estimates are expressed as odds ratios (ORs) and 95% confidence intervals (95% CIs)
Logistic regression model adjusted for age at interview (categorical), ethnicity (Caucasian/non-Caucasian), smoking status (ever/never), comprehensive smoking index (CSI; continuous), body mass index (BMI; continuous), education (categorical) and study.
a
For ordinal variables, test for trend was performed.
b
P-trend after excluding reference category.
c
In postmenopausal women only.
d
Only available in MLCS, TORONTO and WELD.