Table 3. Hazard ratios for heart diseases in breast cancer patients by different adjuvant therapies.
| Total No. | HR (95% CI) for arrhythmia | HR (95% CI) for heart failure | HR (95% CI) for ischemic heart disease | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Treatment variables | N | Model 1 | Model 2 | N | Model 1 | Model 2 | N | Model 1 | Model 2 | |
| Radiotherapy | ||||||||||
| Right-sided | 2948 | 216 | REF (1.00) | REF (1.00) | 80 | REF (1.00) | REF (1.00) | 99 | REF (1.00) | REF (1.00) |
| Left-sided | 3075 | 213 | 0.93 (0.77–1.13) | 0.93 (0.77–1.13) | 87 | 1.03 (0.76–1.40) | 1.07 (0.79–1.45) | 119 | 1.14 (0.87–1.49) | 1.16 (0.89–1.51) |
| Both-sided | 67 | 4 | 0.65 (0.24–1.76) | 0.63 (0.23–1.70) | 4 | 1.81 (0.66–4.95) | 1.75 (0.63–4.85) | 3 | 1.08 (0.34–3.40) | 0.98 (0.31–3.11) |
| Chemotherapy | ||||||||||
| No. | 4604 | 376 | REF (1.00) | REF (1.00) | 133 | REF (1.00) | REF (1.00) | 207 | REF (1.00) | REF (1.00) |
| Anthracyclines-based | 1426 | 83 | 1.18 (0.97–1.45) | 1.08 (0.84–1.39) | 51 | 2.30 (1.70–3.10) | 1.74 (1.20–2.52) | 44 | 1.31 (0.99–1.72) | 1.29 (0.92–1.81) |
| Anthracyclines + taxanes | 286 | 10 | 1.15 (0.63–2.10) | 1.01 (0.53–1.92) | 13 | 4.71 (2.57–8.63) | 3.09 (1.55–6.14) | 6 | 1.36 (0.63–2.93) | 1.29 (0.57–2.95) |
| CMF | 96 | 6 | 1.08 (0.55–2.14) | 1.04 (0.51–2.12) | 3 | 1.21 (0.36–4.00) | 0.90 (0.27–3.04) | 2 | 1.11 (0.49–2.51) | 1.04 (0.46–2.36) |
| Hormone therapy | ||||||||||
| No. | 1424 | 89 | REF (1.00) | REF (1.00) | 49 | REF (1.00) | REF (1.00) | 43 | REF (1.00) | REF (1.00) |
| Tamoxifen | 4247 | 298 | 0.91 (0.72–1.15) | 0.95 (0.74–1.23) | 99 | 0.57 (0.41–0.79) | 0.84 (0.58–1.20) | 142 | 0.91 (0.65–1.27) | 1.03 (0.71–1.48) |
| Aromatase inhibitors | 1550 | 119 | 1.02 (0.77–1.35) | 0.99 (0.74–1.32) | 61 | 1.05 (0.71–1.56) | 1.08 (0.72–1.61) | 85 | 1.53 (1.05–2.24) | 1.52 (1.03–2.26) |
| Trastuzumab* | ||||||||||
| No. | 2137 | 126 | REF (1.00) | REF (1.00) | 38 | REF (1.00) | REF (1.00) | 60 | REF (1.00) | REF (1.00) |
| Yes | 304 | 17 | 1.15 (0.70–1.92) | 1.50 (0.79–2.83) | 13 | 3.05 (1.62–5.76) | 2.34 (1.05–5.22) | 12 | 1.75 (0.94–3.27) | 1.83 (0.85–3.96) |
Total No. refers to the total number of patients. N events refers to the number of observed cases. HR = hazard ratio; CI = confidence interval; CMF = cyclophosphamide, methotrexate, and fluorouracil; REF: reference women in the matched controls from the general population. Hazard ratios are estimated from Cox proportional hazards models with time since diagnosis as underlying time scale. Hazard ratios for model 1 are adjusted for age and calendar period. Hazard ratios for model 2 are multivariable adjusted including age at diagnosis, year of diagnosis, menopausal status, Charlson comorbidity index, clinical stage, tumor size, type of surgery, history of hypertension, chronic pulmonary disease and tobacco abuse, and all treatment variables listed in the table.
Treatment-specific analysis of trastuzumab was restricted to patients diagnosed between 2005 and 2008.