Table 4.

Insulin, C-peptide, C-peptide-to-fructosamine ratio, SHBG, and breast cancer mortality

All women
Premenopausal women
Postmenopausal women
Cases/ControlsOR*95% CIPCases/ControlsOR*95% CIPCases/ControlsOR*95% CIP
Insulin, pmol/L
Tertile 1 (lowest)31/601.00.6920/281.00.7511/321.00.10
Tertile 232/581.40.7-2.812/230.70.2-2.020/353.01.0-9.5
Tertile 3 (highest)28/521.30.6-2.910/240.90.3-2.918/281.90.7-6.6
C-peptide, pmol/L
Tertile 1 (lowest)26/681.00.4314/301.00.7712/381.00.35
Tertile 236/541.50.7-3.218/231.30.4-3.818/311.70.6-5.4
Tertile 3 (highest)29/481.60.7-3.610/230.80.2-2.819/252.30.7-7.5
C-peptide/Fructosamine ratio
Tertile 1 (lowest)27/661.00.4515/301.00.2812/361.00.17
Tertile 232/511.40.7-3.117/191.80.6-5.715/321.30.4-3.9
Tertile 3 (highest)31/521.60.7-3.510/260.60.2-2.221/262.70.9-8.5
SHBG, nmol/L
Tertile 1 (lowest)27/531.00.9912/191.00.4915/341.00.87
Tertile 231/571.00.5-2.113/260.70.2-2.318/311.20.4-3.4
Tertile 3 (highest)29/551.00.4-2.215/280.40.1-1.715/281.30.5-4.1
  • * OR adjusted for age and stage at diagnosis, treatment, estrogen receptor status, WHR, and family history of breast cancer.

  • Tertile cutpoints: Insulin: Q1 (<54), Q2 (54-91), Q3 (92+). C-peptide: Q1 (<330), Q2 (330-666), Q3 (667+). SHBG: Q1 (<45), Q2 (45-66), Q3 (67+). Diabetics excluded from insulin and C-peptide analyses.