Table 4.

Adjusted RR for quartile levels of creatinine-adjusted melatonin (ng/mg of creatinine) for all breast cancer combined and for ER+ breast cancer alone by time interval between urinary collection and diagnosis

CasesControlsRR (95% CI)PtrendRRa (95% CI)Ptrend
All cases, ≤4 y
 Q1 (<6.69)17461.0 (ref.)0.181.0 (ref.)0.11
 Q2 [6.69–12.81)21431.37 (0.63–3.01)1.25 (0.51–3.06)
 Q3 [12.81–22.18)21351.71 (0.77–3.83)1.85 (0.75–4.57)
 Q4 (≥22.18)21361.69 (0.74–3.84)1.94 (0.75–5.03)
All cases, >4 y
 Q1 (<6.69)38741.0 (ref.)0.931.0 (ref.)0.89
 Q2 [6.69–12.81)36790.89 (0.52–1.53)0.97 (0.54–1.75)
 Q3 [12.81–22.18)48841.12 (0.65–1.91)1.09 (0.60–1.97)
 Q4 (≥22.18)37800.90 (0.52–1.56)1.00 (0.55–1.83)
ER+ cases, ≤ 4 y
 Q1 (<6.69)14301.0 (ref)0.651.0 (ref)0.72
 Q2 [6.69–12.81)13310.94 (0.36–2.46)0.64 (0.20–2.04)
 Q3 [12.81–22.18)15221.49 (0.55–4.03)1.49 (0.50–4.43)
 Q4 (≥22.18)12251.10 (0.39–3.13)0.90 (0.27–2.95)
ER+ cases, >4 y
 Q1 (<6.69)28511.0 (ref.)0.711.0 (ref.)0.72
 Q2 [6.69–12.81)32650.90 (0.49–1.64)0.94 (0.50–1.79)
 Q3 [12.81–22.18)34690.89 (0.47–1.66)0.82 (0.41–1.63)
 Q4 (≥22.18)28580.88 (0.46–1.68)0.92 (0.46–1.83)

Abbreviation: RR, relative risk.

  • aAdjusted for body mass index, education, and bilateral oophorectomy.