| Cases/person years | HR1 (95% CI) | HR2 (95% CI) | HRinvasive (95% CI) |
---|---|---|---|---|
Volpara density grades | ||||
 VDG1 | 12/46,089 | ref | NA | ref |
 VDG2 | 72/99,086 | 2.85 (1.55 ; 5.25) | NA | 3.03 (1.61 ; 5.73) |
 VDG3 | 100/73,207 | 5.61 (3.07 ; 10.27) | NA | 6.01 (3.20 ; 11.27) |
 VDG4 | 40/20,314 | 8.37 (4.34 ; 16.17) | NA | 9.30 (4.71 ; 18.37 |
P trend | Â | <0.001 | Â | <0.001 |
Percent dense volume (in quartiles) | ||||
 Q1 (<4.8%) | 16/58,411 | ref | NA | ref |
 Q2 (4.8–6.4%) | 45/61,153 | 2.72 (1.54 ; 4.82) | NA | 2.78 (1.55 ; 5.01) |
 Q3 (6.4–9.8%) | 75/60,499 | 4.71 (2.74 ; 8.10) | NA | 4.99 (2.86 ; 8.72) |
 Q4 (>9.8%) | 88/58,633 | 5.89 (3.42 ; 10.14) | NA | 6.22 (3.56 ; 10.89) |
P trend | Â | <0.001 | Â | <0.001 |
Percent dense volume (per SD increase)# | 224/238,696 | 1.65 (1.45 ; 1.87) | NA | 1.68 (1.48 ; 1.91 |
Dense volume (VDG-like categories) | ||||
 C1 (<39.8 cm3) | 31/45,851 | ref | ref | ref |
 C2 (39.9–65.2 cm3) | 74/96,827 | 1.13 (0.75 ; 1.73) | 1.43 (0.92 ; 2.21) | 1.48 (0.95 ; 2.30) |
 C3 (65.3–110.1 cm3) | 75/74,190 | 1.51 (0.99 ; 2.29) | 2.32 (1.48 ; 3.64) | 2.32 (1.47 ; 3.67) |
 C4 (>110.1 cm3) | 44/21,828 | 3.01 (1.89 ; 4.79) | 4.92 (2.98 ; 8.12) | 5.24 (3.16 ; 8.70) |
P trend | Â | <0.001 | <0.001 | <0.001 |
Dense volume (in quartiles)* | ||||
 Q1 (<42.9 cm3) | 43/57,909 | ref | ref | ref |
 Q2 (42.9–57.8 cm3) | 42/59,364 | 0.95 (0.62 ; 1.46) | 1.14 (0.74 ; 1.77) | 1.22 (0.78 ; 1.90) |
 Q3 (57.9–78.9 cm3) | 56/60,359 | 1.25 (0.84 ; 1.87) | 1.74 (1.14 ; 2.66) | 1.83 (1.19 ; 2.81) |
 Q4 (>78.9 cm3) | 83/61,065 | 1.83 (1.26 ; 2.66) | 2.79 (1.86 ; 4.19) | 2.89 (1.91 ; 4.38) |
P trend | Â | <0.001 | <0.001 | <0.001 |
Dense volume (per SD increase)# | 224/238,696 | 1.39 (1.22 ; 1.59) | 1.63 (1.42 ; 1.87) | 1.65 (1.44 ; 1.90) |