Table 2.
- Adjusted Odds Ratios (95% Confidence Intervals) for Parity, Oral Contraceptive Use, Menopausal Status and Hormone Replacement Therapy Use Among Women Cases and Controls.
| Controlsc | Bladder Cancer Casesd | ||||
|---|---|---|---|---|---|
| n=379 | % | n=197 | % | ORa (95% CI) | |
| Number of Births | |||||
| None | 39 | 10% | 23 | 6% | 1.00 (reference) |
| Some | 340 | 90% | 174 | 46% | 0.71 (0.40–1.26) |
| 1–2 | 161 | 47% | 78 | 23% | 0.67 (0.36–1.24) |
| 3–4 | 132 | 39% | 71 | 21% | 0.75 (0.40–1.39) |
| ≥5 | 47 | 14% | 25 | 7% | 0.74 (0.35–1.57) |
| p for trend (categorical) | 0.632 | ||||
| Oral Contraceptive Use | |||||
| Never | 188 | 57% | 108 | 58% | 1.00 (reference) |
| Ever | 143 | 43% | 79 | 42% | 1.55 (0.83–2.89) |
| Total Duration of Use | |||||
| No Use | 188 | 57% | 108 | 59% | 1.00 (reference) |
| 3 months – 2 years | 43 | 13% | 29 | 16% | 1.70 (0.77–3.79) |
| 3–6 years | 46 | 14% | 13 | 7% | 0.87 (0.31–2.46) |
| 7 years or more | 52 | 16% | 33 | 18% | 1.73 (0.81–3.73) |
| p for trend | 0.259 | ||||
| Time Since Last Use | |||||
| No Use | 188 | 57% | 108 | 58% | 1.00 (reference) |
| 25 or more years | 41 | 12% | 40 | 21% | 2.13 (1.08–4.20) |
| 0–24 years | 102 | 31% | 39 | 21% | 0.82 (0.35–1.92) |
| p for trend | 0.91 | ||||
| Menopause Status | |||||
| Premenopausal | 68 | 21% | 26 | 14% | 1.00 (reference) |
| Postmenopausal | 262 | 79% | 160 | 86% | 1.30 (0.45–3.77) |
| Natural | 156 | 60% | 95 | 59% | 0.84 (0.21–3.39) |
| Surgical (Bilateral Oophorectomy) | 48 | 18% | 31 | 19% | 2.80 (0.65–12.05) |
| Age at Menopauseb | |||||
| ≥45 years | 158 | 65% | 99 | 63% | 1.00 (reference) |
| <45 years | 85 | 35% | 59 | 37% | 1.33 (0.72–2.47) |
| Age at Natural Menopauseb | |||||
| ≥45 years | 124 | 86% | 79 | 83% | 1.00 (reference) |
| <45 years | 20 | 14% | 16 | 17% | 0.73 (0.21–2.54) |
| Age at Bilateral Oophorectomyb | |||||
| ≥45 years | 23 | 50% | 10 | 33% | 1.00 (reference) |
| <45 years | 23 | 50% | 20 | 67% | 5.37 (1.20–23.93) |
| Hormone Replacement Therapy Useb | |||||
| Never | 151 | 58% | 101 | 64% | 1.00 (reference) |
| Ever | 110 | 42% | 58 | 36% | 1.08 (0.60–1.96) |
Adjusted for age and smoking status
Restricted to post-menopausal women only
48 controls missing data on oral contraceptive use, 2 missing data on duration of oral contraceptive use, 49 missing data on menopausal status, 19 missing data on age at menopause, 12 missing age of natural menopause, 2 missing age at bilateral oophorectomy, 1 post-menopausal women missing data on HRT use
10 cases missing data on oral contraceptive use, 4 missing data on duration of oral contraceptive use, 11 missing data on menopausal status, 2 missing data on age at menopause, 1 missing age of bilateral oophorectomy, 1 post-menopausal women missing data on HRT use