Table 3.
Association between radiation to the carotid artery and carotid plaque scores, intima-media thickness, total cerebral blood flow, and brain perfusion in breast cancer survivors
| Outcome | Small part carotid artery in radiation field (n = 102) | Carotid artery not in radiation field (n = 17) |
Model I β (95% CI)a |
Model II β (95% CI)a |
Model III β (95% CI)a |
Carotid artery in radiation field (n = 52) | Model I β (95% CI)a |
Model II β (95% CI)a |
Model III β (95% CI)a |
|---|---|---|---|---|---|---|---|---|---|
| Carotid plaque score, median (IQR) | |||||||||
| Total | 1.0 (0.0–3.0) | 2.0 (1.0–4.0) | 0.35 (− 0.18;0.89) | 0.22 (− 0.29;0.74) | 1.5 (1.0–4.3) | 0.31 (− 0.05;0.67) | 0.27 (− 0.07;0.62) | ||
| Left | 1.0 (0.0–2.0) | 1.0 (0.0–2.0) | 0.15 (− 0.44;0.71) | 0.05 (− 0.53; 0.60) | 1.0 (0.0–2.0) | 0.31 (− 0.07;0.68) | 0.28 (− 0.09;0.64) | ||
| Right | 1.0 (0.0–2.0) | 1.0 (0.0–3.0) | 0.53 (− 0.04;1.09) | 0.39 (− 0.15;0.91) | 1.0 (0.0–2.0) | 0.31 (− 0.09;1.09) | 0.22 (− 0.17;0.61) | ||
| Intima-media thickness, mean (SD) | |||||||||
| Total | 0.82 (0.13) | 0.84 (0.17) | 0.01 (− 0.06;0.08) | 0.00 (− 0.06;0.07) | 0.89 (0.14) | 0.06 (0.01;0.10) | 0.05 (0.01;0.09) | ||
| Left | 0.83 (0.15) | 0.84 (0.16) | 0.03 (− 0.03;0.08) | 0.03 (− 0.02;0.08) | 0.87 (0.14) | 0.05 (− 0.02;0.11) | 0.05 (− 0.02;0.11) | ||
| Right | 0.81 (0.14) | 0.85 (0.18) | 0.03 (− 0.02;0.08) | 0.02 (− 0.02;0.07) | 0.90 (0.17) | 0.10 (0.03;0.17) | 0.09 (0.01;0.16) | ||
| Cerebral blood flow, ml/min, mean (SD) | |||||||||
| Total | 524 (91) | 505 (62) | − 21.6 (− 66.7;23.5) | − 21.7 (− 67.5;24.2) | − 16.4 (− 61.7;28.8) | 511 (92) | − 17.3 (− 47.2;12.5) | − 13.7 (− 44.9;17.5) | − 16.4 (− 61.7;28.8) |
| Brain perfusion, ml/min per 100 ml, mean (SD) | |||||||||
| Total | 57.5 (9.1) | 56.9 (6.6) | − 1.2 (− 5.8;3.5) | − 1.2 (− 5.9;3.5) | − 0.6 (− 5.2;4.0) | 57.6 (9.3) | − 0.5 (− 3.6;2.5) | − 0.5 (− 3.7;2.7) | − 0.1 (− 3.3;3.1) |
Model I = adjusted for age and body mass index; Model II = as Model I, plus: systolic blood pressure, diastolic blood pressure, age at menopause, prevalence of diabetes, smoking status, use of antihypertensive medication, anticoagulant medication, and lipid-lowering medication, and education; Model III = as Model II, plus: total mean intima-media thickness and total plaque score
CI confidence interval, IMT intima-media thickness, IQR interquartile range; SD standard deviation
aDifference in median total plaque score, mean intima-media thickness, mean total cerebral blood flow, or mean brain perfusion between breast cancer survivors treated with carotid artery partly in radiation field (i.e., internal mammary chain radiation, reference group), without carotid artery in radiation field, and with carotid artery in radiation field (i.e., McWhirter or supraclavicular lymph node radiation)