N | Age-adjusted OR | N' | Age and fibrinogen-adjusted OR | |
All VTE | ||||
Serum iron, at VTE | 493 | 0.91 (0.86 to 0.97) | 449 | 0.90 (0.84 to 0.97) |
Serum TfSI, at VTE | 494 | 0.95 (0.92 to 0.99) | 450 | 0.95 (0.91 to 0.99) |
Ferritin | 243 | 1.00 (0.98 to 1.01) | 226 | 0.99 (0.98 to 1.01) |
Haemoglobin | 543 | 0.94 (0.81 to 1.05) | 487 | 0.94 (0.80 to 1.11) |
Platelets | 550 | 1.00 (1.00 to 1.01) | 495 | 1.00 (1.00 to 1.01) |
On iron treatment (oral) | 593 | 1.52 (0.73 to 3.20) | 496 | 1.93 (0.89 to 4.20) |
Ever transfused | 599 | 0.93 (0.31 to 2.84) | 494 | 1.00 (0.32 to 3.14) |
Using hormones | 591 | 0.92 (0.31 to 2.70) | 487 | 1.11 (0.37 to 3.34) |
Using tranexamic acid | 592 | 1.02 (1.00 to 1.05) | 489 | 1.30 (0.27 to 6.05) |
Community restricted | ||||
Serum iron, at VTE | 493 | 0.91 (0.84 to 0.99) | 449 | 0.90 (0.82 to 0.99) |
Serum TfSI, at VTE | 494 | 0.95 (0.91 to 0.996) | 450 | 0.94 (0.89 to 0.99) |
Ferritin | 243 | 1.00 (0.98 to 1.01) | 226 | 1.00 (0.98 to 1.01) |
Haemoglobin | 543 | 0.89 (0.72 to 1.09) | 487 | 0.89 (0.72 to 1.10) |
Platelets | 550 | 1.00 (1.00 to 1.01) | 495 | 1.00 (0.99 to 1.01) |
On iron treatment (oral) | 599 | 0.90 (0.32 to 2.490) | 496 | 1.07 (0.37 to 3.10) |
Ever transfused | 599 | 0.94 (0.20 to 4.35) | 494 | 1.00 (0.21 to 4.74) |
Using hormones | 591 | 1.80 (0.58 to 5.54) | 487 | 1.55 (0.43 to 5.64) |
Using tranexamic acid | 593 | 0.94 (0.12 to 7.40) | 489 | 1.25 (0.15 to 10.23) |
ORs for all VTE occurring in series 1 and 2 combined, with ORs significantly different to 1.00 denoted in bold. A series indicator variable was used to confirm the validity of series pooling. N, number of observations for age-adjusted figures; N', number including fibrinogen, selected as acute phase markers because available in 449 patients compared with 320 for C-reactive protein. Intravenous iron could not be part of any model due to the low frequency of use. TfSI, transferrin saturation index.