Table 4.
Associations between changing slope in body mass index and clinical outcomes: multivariable Cox models*
| Overall survival | Breast cancer-specific survival | Disease-free survival | ||||
|---|---|---|---|---|---|---|
| HR (95% CI) | P | HR (95% CI) | P | HR (95% CI) | P | |
| Changing slope in BMI | ||||||
| Loss > 0.5 kg/m2/year | 2.60 (1.88–3.59) | < 0.001 | 3.05 (1.91–4.86) | < 0.001 | 2.12 (1.52–2.96) | < 0.001 |
| Stable (≤ 0.5 kg/m2/year) | 1.0 (ref.) | 1.0 (ref.) | 1.0 (ref.) | |||
| Gain > 0.5 kg/m2/year | 1.60 (1.10–2.33) | 0.014 | 1.73 (1.04–2.87) | 0.035 | 1.54 (1.06–2.24) | 0.024 |
| Race/ethnicity | ||||||
| Black vs. White | 1.98 (1.49–2.64) | < 0.001 | 2.06 (1.40–3.04) | < 0.001 | 2.02 (1.51–2.69) | < 0.001 |
| Asian vs. White | 1.38 (0.59–3.18) | 0.46 | 1.92 (0.75–4.90) | 0.18 | 1.21 (0.49–3.03) | 0.68 |
| Hispanic vs. White | 0.32 (0.08–1.30) | 0.11 | 0.59 (0.14–2.45) | 0.47 | 0.31 (0.08–1.28) | 0.11 |
| Age per 10 years | 1.33 (1.19–1.49) | < 0.001 | 1.16 (1.01–1.34) | 0.036 | 1.35 (1.20–1.51) | < 0.001 |
| Carlson comorbidity index | ||||||
| 1 vs. 0 | 1.28 (0.84–1.94) | 0.26 | 1.41 (0.84–2.38) | 0.20 | 1.35 (0.88–2.09) | 0.17 |
| 2 vs. 0 | 2.62 (1.82–3.76) | < 0.001 | 1.28 (0.70–2.35) | 0.43 | 2.87 (1.99–4.13) | < 0.001 |
| 3 vs. 0 | 3.36 (2.17–5.18) | < 0.001 | 1.05 (0.43–2.56) | 0.91 | 3.48 (2.24–5.41) | < 0.001 |
| Tumor stage | ||||||
| 0 vs. 1 | 0.67 (0.16–2.82) | 0.59 | 0.0** | 0.68 (0.16–2.87) | 0.60 | |
| 2 vs. 1 | 1.34 (0.96–1.86) | 0.087 | 2.42 (1.43–4.08) | 0.001 | 1.40 (1.00–1.97) | 0.048 |
| 3 vs. 1 | 2.71 (1.83–4.01) | < 0.001 | 5.92 (3.35–10.48) | < 0.001 | 2.46 (1.63–3.70) | < 0.001 |
| Histologic grade | ||||||
| 2 vs. 1 | 1.48 (0.86–2.54) | 0.16 | 4.41 (1.06–18.41) | 0.042 | 1.43 (0.85–2.39) | 0.18 |
| 3 vs. 1 | 1.76 (0.97–3.17) | 0.06 | 7.32 (1.70–31.54) | 0.008 | 1.60 (0.91–2.84) | 0.11 |
| Molecular subtype | ||||||
| ER/PR+, her2+ vs. ER/PR+/her2− | 0.85 (0.52–1.40) | 0.53 | 0.53 (0.26–1.10) | 0.088 | 0.80 (0.48–1.33) | 0.38 |
| ER/PR−, her2+ vs. ER/PR+/her2− | 0.86 (0.40–1.84) | 0.70 | 0.93 (0.36–2.38) | 0.88 | 0.69 (0.31–1.55) | 0.37 |
| Triple negative vs. ER/PR+/her2− | 1.19 (0.66–2.14) | 0.56 | 1.28 (0.60–2.71) | 0.53 | 0.95 (0.52–1.74) | 0.87 |
| Radiotherapy | 0.86 (0.65–1.14) | 0.30 | 0.70 (0.48–1.02) | 0.063 | 1.02 (0.76–1.36) | 0.91 |
| Hormonal therapy | 0.93 (0.56–1.54) | 0.78 | 0.96 (0.48–1.92) | 0.91 | 0.96 (0.57–1.61) | 0.88 |
| Chemotherapy | 1.10 (0.75–1.62) | 0.62 | 0.91 (0.52–1.57) | 0.73 | 1.25 (0.85–1.85) | 0.26 |
*All variables in the table are included in the three multivariable Cox models
**No DCIS patents died from breast cancer
Abbreviation: HR hazard ratio, CI confidence intervals, BMI body mass index, ER estrogen receptor, PR progesterone receptor