Adjusted RRs for quartile levels of creatinine-adjusted melatonin (ng/mg of creatinine) for all breast cancer combined and for ER+ breast cancer only
| Cases | Controls | RR (95% CI) | Ptrend | RRa (95% CI) | Ptrend | |
|---|---|---|---|---|---|---|
| All cases | ||||||
| Q1 (<6.69) | 58 | 127 | 1.0 (ref.) | 0.41 | 1.0 (ref.) | 0.27 |
| Q2 [6.69–12.81) | 60 | 130 | 1.02 (0.66–1.56) | 1.07 (0.67–1.71) | ||
| Q3 [12.81–22.18) | 74 | 129 | 1.26 (0.82–1.94) | 1.26 (0.79–2.01) | ||
| Q4 (≥22.18) | 66 | 129 | 1.13 (0.73–1.75) | 1.25 (0.78–2.02) | ||
| ER+ cases | ||||||
| Q1 (<6.69) | 48 | 89 | 1.0 (ref.) | 0.84 | 1.0 (ref.) | 0.80 |
| Q2 [6.69–12.81) | 40 | 90 | 0.83 (0.55–1.38) | 0.82 (0.48–1.42) | ||
| Q3 [12.81–22.18) | 47 | 87 | 0.99 (0.58–1.69) | 0.93 (0.53–1.65) | ||
| Q4 (≥22.18) | 41 | 85 | 0.89 (0.53–1.51) | 0.88 (0.50–1.56) | ||
Abbreviation: RR, relative risk.
↵aAdjusted for body mass index, education, and bilateral oophorectomy.