TABLE 1.
Associations (HRs and 95% CIs) between quartiles of the Dietary Approaches to Stop Hypertension (DASH) diet and risk of breast cancer outcomes in the Sister Study1
| Q1 | Q2 | Q3 | Q4 | P-trend2 | |
|---|---|---|---|---|---|
| Total invasive breast cancer | |||||
| Cases, n | 388 | 486 | 409 | 417 | |
| Age-adjusted | 1.00 (reference) | 0.92 (0.80, 1.05) | 0.95 (0.83, 1.10) | 0.83 (0.72, 0.96) | 0.02 |
| MV-adjusted3 | 1.00 (reference) | 0.88 (0.77, 1.01) | 0.89 (0.77, 1.03) | 0.78 (0.67, 0.90) | 0.001 |
| ER+ breast cancer | |||||
| Cases, n | 274 | 360 | 314 | 321 | |
| Age-adjusted | 1.00 (reference) | 0.96 (0.82, 1.12) | 1.02 (0.87, 1.20) | 0.89 (0.76, 1.05) | 0.30 |
| MV-adjusted3 | 1.00 (reference) | 0.90 (0.76, 1.05) | 0.92 (0.78, 1.09) | 0.81 (0.68, 0.96) | 0.03 |
| ER– breast cancer | |||||
| Cases, n | 56 | 68 | 47 | 46 | |
| Age-adjusted | 1.00 (reference) | 0.91 (0.64, 1.30) | 0.78 (0.53, 1.16) | 0.67 (0.45, 1.00) | 0.02 |
| MV-adjusted3 | 1.00 (reference) | 0.89 (0.62, 1.28) | 0.75 (0.50, 1.12) | 0.61 (0.40, 0.94) | 0.006 |
| ER+/PR+ breast cancer | |||||
| Cases, n | 231 | 314 | 257 | 259 | |
| Age-adjusted | 1.00 (reference) | 1.00 (0.84, 1.19) | 1.01 (0.84, 1.21) | 0.88 (0.73, 1.05) | 0.20 |
| MV-adjusted3 | 1.00 (reference) | 0.94 (0.79, 1.11) | 0.91 (0.76, 1.10) | 0.80 (0.66, 0.96) | 0.03 |
| ER–/PR– breast cancer | |||||
| Cases, n | 52 | 61 | 43 | 43 | |
| Age-adjusted | 1.00 (reference) | 0.88 (0.61, 1.27) | 0.77 (0.51, 1.16) | 0.68 (0.45, 1.03) | 0.02 |
| MV-adjusted3 | 1.00 (reference) | 0.86 (0.59, 1.25) | 0.73 (0.48, 1.11) | 0.61 (0.39, 0.94) | 0.006 |
| ER–/PR–/HER2– breast cancer | |||||
| Cases, n | 37 | 45 | 31 | 27 | |
| Age-adjusted | 1.00 (reference) | 0.92 (0.59, 1.43) | 0.79 (0.49, 1.29) | 0.61 (0.37, 1.02) | 0.02 |
| MV-adjusted3 | 1.00 (reference) | 0.90 (0.57, 1.39) | 0.75 (0.46, 1.24) | 0.56 (0.33, 0.95) | 0.01 |
Values are HRs (95% CIs) unless otherwise indicated. ER, estrogen receptor; HER2, human epidermal growth factor receptor-2; MET, metabolic equivalent of task; MV, multivariable; PR, progesterone receptor.
P value for the continuous DASH score (Wald test).
Adjusted for total energy intake (kcal/d, continuous), race/ethnicity (white [reference], black, other), income (<$50,000 [reference], $50,000 to <$100,000, ≥$100,000/y), smoking (0, >0 to <10, 10 to <20, 20 to <30, ≥30 pack-years), BMI (<18.5, 18.5 to <25 [reference], 25 to <30, 30 to <35, ≥35), physical activity (MET-h/wk, continuous), height (inches, continuous), education (high school or less [reference], some college, college graduate or more), alcohol intake (none [reference], <0.5, ≥0.5 to 1, ≥1 to 2, ≥2 drinks/d), mother diagnosed with breast cancer (yes vs. no [reference]), age at first live birth (nulliparous [reference], <21, 21 to <25, 25 to <29, 29–32, >32 y), parity (0 or 1 [reference], 2 or 3, 4 or more), hormone replacement therapy (none [reference], estrogen only, estrogen and progesterone, both estrogen and progesterone), age at menopause (premenopausal [reference], <40, 40 to <50, 50 to <55, ≥55 y), oral contraception use (yes [reference] vs. no), age at menarche (<12 [reference], 12 to <12.5, 12.5 to <13.5, 13.5 to <14.5, ≥14.5 y), lifetime duration of breastfeeding (0 [reference], >0 to <50, 50 to <100, ≥100 wk), and time of last mammogram (<1 [reference], 1 to <2, ≥2 y ago).