Table 4.
Evaluation of acquisition parameters on the association between adjusted mammographic densitya estimated from enrollment (screen-film) mammograms and risk of breast cancer in the Mayo Mammography Health Study cohort (2003 to 2009)
| Models with addition of acquisition parameters | ||||||||
|---|---|---|---|---|---|---|---|---|
| Models with no acquisition parameters | kVp - 3 levels | mAs | Thickness | Compression | All 4 acquisitionparameters | |||
| Percent density | Number of cases | Person-years in Subcohort | HRb(95% CI) | HRb(95% CI) | HRb(95% CI) | HRb(95% CI) | HRb(95% CI) | HRb(95% CI) |
| 0% to 5.0% | 42 | 2,071.0 | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) |
| 5.1% to 15.0% | 76 | 2,678.7 | 1.89 (1.28, 2.80) | 1.89 (1.28, 2.79) | 1.88 (1.27, 2.78) | 1.88 (1.27, 2.78) | 1.90 (1.28, 2.80) | 1.88 (1.27, 2.79) |
| 15.1% to 25.0% | 53 | 2,327.7 | 1.88 (1.22, 2.91) | 1.86 (1.20, 2.88) | 1.86 (1.21, 2.88) | 1.88 (1.22, 2.90) | 1.89 (1.22, 2.92) | 1.88 (1.21, 2.92) |
| 25.1% + | 83 | 2,511.6 | 3.57 (2.30, 5.55) | 3.51 (2.23, 5.48) | 3.51 (2.25, 5.48) | 3.60 (2.32, 5.59) | 3.54 (2.28, 5.50) | 3.56 (2.22, 5.69) |
| kVp | - | 1.04 (0.87, 1.25) | - | - | - | 1.01 (0.82, 1.24) | ||
| mAs | - | - | 1.04 (0.89, 1.21) | - | - | 1.00 (0.79, 1.26) | ||
| Thickness, mm | - | - | - | 1.08 (0.92, 1.26) | - | 1.06 (0.83, 1.35) | ||
| Compression, pounds | - | - | - | - | 0.93 (0.82, 1.06) | 0.94 (0.82, 1.07) | ||
| C-statistic | 0.64 | 0.64 | 0.64 | 0.63 | 0.64 | 0.63 | ||
| BI-RADS | ||||||||
| 1 | 41 | 2,082.8 | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) |
| 2 | 106 | 3,778.4 | 1.63 (1.13, 2.35) | 1.62 (1.12, 2.33) | 1.62 (1.12, 2.33) | 1.63 (1.13, 2.35) | 1.64 (1.13, 2.36) | 1.61 (1.11, 2.33) |
| 3 | 87 | 3,078.4 | 2.04 (1.37, 3.03) | 1.98 (1.32, 2.97) | 2.00 (1.34, 2.98) | 2.04 (1.38, 3.04) | 2.04 (1.37, 3.03) | 1.96 (1.30, 2.98) |
| 4 | 20 | 649.3 | 2.72 (1.53, 4.81) | 2.62 (1.47, 4.68) | 2.65 (1.49, 4.71) | 2.78 (1.57, 4.94) | 2.69 (1.52, 4.77) | 2.56 (1.38, 4.75) |
| kVp | - | - | 1.07 (0.89, 1.28) | - | - | - | 1.06 (0.84, 1.33) | |
| mAs | - | - | 1.06 (0.91, 1.23) | - | - | 1.05 (0.85, 1.29) | ||
| Thickness, mm | - | - | - | 1.07 (0.92, 1.25) | - | 0.99 (0.78, 1.27) | ||
| Compression, pounds | - | - | - | - | 0.92 (0.81, 1.05) | 0.92 (0.80, 1.05) | ||
| C-statistic | 0.62 | 0.62 | 0.62 | 0.62 | 0.62 | |||
aAnalyses adjusted for age, menopausal status, post-menopausal hormone use, and body mass index. bHazard ratios (HRs) corresponding to milliampere-seconds (mAs), thickness, and compression refer to a 1 standard deviation (SD) change in the respective parameter (SD: mAs = 49.5, thickness = 12.7, compression = 5.6). HRs corresponding to voltage peak (kVp) are based on a tri-level ordinal variable (22-25, 26-27, 28-32). Owing to missing acquisition parameters, 18 cases and 47 controls that were included in the analyses depicted in Table 2 are not included here. BI-RADS, Breast Imaging Reporting and Data System; CI, confidence interval; Ref., reference value.