Table 3.
Summary odds ratios (ORs) and 95% confidence intervals (CIs) for the associations of aspirin and NSAID use with risk of ovarian cancer in the Ovarian Cancer Association Consortium (1992–2009)*
| Exposure categorization | Aspirin | Nonaspirin NSAID | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Control | Case | OR† | (95% CI) | I 2§ | Control | Case | OR† | (95% CI) | I 2§ | |
| Frequency and dose‡ | ||||||||||
| No regular use | 2138 | 1359 | 1.00 | (referent) | 2053 | 1274 | 1.00 | (referent) | ||
| <30 days per month, low dose | 19 | 11 | 1.12 | (0.52 to 2.43) | 0.0 | 175 | 115 | 1.08 | (0.74 to 1.59) | 52.1 |
| Daily, low Dose | 298 | 118 | 0.64 | (0.50 to 0.81) | 0.0 | 263 | 143 | 0.88 | (0.70 to 1.11) | 0.0 |
| <30 days per month, high dose | 93 | 66 | 1.25 | (0.88 to 1.76) | 0.0 | 136 | 82 | 0.77 | (0.57 to 1.04) | 0.0 |
| Daily, high Dose | 322 | 144 | 0.78 | (0.62 to 0.97) | 0.0 | 353 | 148 | 0.75 | (0.60 to 0.94) | 3.8 |
* NSAID = nonsteroidal anti-inflammatory drug.
† Summary odds ratios were estimated using random-effects meta-analytic model. Results were adjusted for age (<50, 50–54, 55–59, 60v64, 65–69, ≥70 years), race (white, black, other), oral contraceptive use (ever/never), parity (0, 1, ≥2), menopausal status (premenopausal/postmenopausal), body mass index category (<25, 25–29.9, ≥30kg/m2) if available, and first-degree family history of breast cancer, male breast cancer, or ovarian cancer. All statistical tests were two-sided.
‡ Analyses included three studies for frequency and dose analyses (37,38,40). Dose categories for aspirin: low: <100mg, high: ≥100mg; for nonaspirin NSAIDs and acetaminophen: low: <500mg, high: ≥500mg.
§ I 2 is the percentage of variation across studies due to heterogeneity rather than chance.