| Cases/person years | HR1 (95% CI) | HR2 (95% CI) | HRinvasive (95% CI) |
---|---|---|---|---|
Volpara density grades | ||||
 VDG1 | 58/46,089 | ref | NA | ref |
 VDG2 | 215/99,086 | 1.78 (1.33 ; 2.38) | NA | 1.89 (1.38 ; 2.58) |
 VDG3 | 189/73,207 | 2.38 (1.76 ; 3.20) | NA | 2.53 (1.83 ; 3.49) |
 VDG4 | 61/20,314 | 3.14 (2.17 ; 4.55) | NA | 3.54 (2.39 ; 5.24) |
P trend | Â | <0.001 | Â | <0.001 |
Percent dense volume (in quartiles) | ||||
 Q1 (<4.8%) | 79/58,411 | ref | NA | ref |
 Q2 (4.8–6.4%) | 127/61,153 | 1.57 (1.19 ; 2.08) | NA | 1.61 (1.19 ; 2.18) |
 Q3 (6.4–9.8%) | 161/60,499 | 2.17 (1.65 ; 2.84) | NA | 2.33 (1.74 ; 3.11) |
 Q4 (>9.8%) | 156/58,633 | 2.42 (1.83 ; 3.20) | NA | 2.52 (1.87 ; 3.40) |
P trend | Â | <0.001 | Â | <0.001 |
Percent dense volume (per SD increase)# | 523/238,696 | 1.36 (1.25 ; 1.48) | NA | 1.38 (1.26 ; 1.51) |
Dense volume (VDG-like categories) | ||||
 C1 (<39.8 cm3) | 69/45,851 | ref | ref | ref |
 C2 (39.9– 65.2 cm3) | 197/96,827 | 1.37 (1.04 ; 1.80) | 1.53 (1.15 ; 2.05) | 1.69 (1.24 ; 2.30) |
 C3 (65.3– 110.1 cm3) | 176/74,190 | 1.66 (1.26 ; 2.20) | 2.06 (1.52 ; 2.80) | 2.27 (1.63 ; 3.14) |
 C4 (>110.1 cm3) | 81/21,828 | 2.79 (2.02 ; 3.86) | 3.55 (2.49 ; 5.05) | 3.66 (2.50 ; 5.36) |
P trend | Â | <0.001 | <0.001 | <0.001 |
Dense volume (in quartiles) | ||||
 Q1 (<42.9 cm3) | 91/57,909 | ref | ref | ref |
 Q2 (42.9–7.8 cm3) | 113/59,364 | 1.22 (0.93 ; 1.61) | 1.35 (1.01 ; 1.80) | 1.47 (1.08 ; 1.99) |
 Q3 (57.9–78.9 cm3) | 136/60,359 | 1.48 (1.13 ; 1.93) | 1.77 (1.33 ; 2.35) | 1.92 (1.42 ; 2.60) |
 Q4 (>78.9 cm3) | 183/61,065 | 2.08 (1.61 ; 2.68) | 2.60 (1.96 ; 3.45) | 2.71 (2.01 ; 3.67) |
P trend | Â | <0.001 | <0.001 | <0.001 |
Dense volume (per SD increase)# | 523/238,696 | 1.34 (1.23 ; 1.46) | 1.45 (1.32 ; 1.60) | 1.45 (1.32 ; 1.60) |