Multivariable relative risk and 95% confidence interval for the association between physical activity and death by cause according to stage of breast cancer at diagnosis among women in the California Teachers Study
| Physical activity (h/wk/y) | Breast cancer deaths (n = 221) | Death due to any cause (n = 460) | Death due to any cause other than breast cancer (n = 239) | |||
|---|---|---|---|---|---|---|
| Localized (n = 2,437) | Nonlocalized* (n = 1,074) | Localized (n = 2,437) | Nonlocalized* (n = 1,074) | Localized (n = 2,437) | NonLocalized* (n = 1,074) | |
| RR (95% CI) | RR (95% CI) | RR (95% CI) | RR (95% CI) | RR (95% CI) | RR (95% CI) | |
| Long-term physical activity | ||||||
| Combined† | ||||||
| Low | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Intermediate | 0.48 (0.25-0.92) | 0.74 (0.46-1.17) | 0.80 (0.57-1.13) | 0.85 (0.57-1.27) | 0.88 (0.58-1.31) | 1.39 (0.59-3.29) |
| High | 0.35 (0.17-0.73) | 0.57 (0.34-0.96) | 0.75 (0.51-1.09) | 0.66 (0.42-1.05) | 0.92 (0.60-1.44) | 0.89 (0.33-2.43) |
| P trend‡ | 0.008 | 0.04 | 0.15 | 0.07 | 0.78 | 0.74 |
| Recent physical activity | ||||||
| Combined† | ||||||
| Low | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Intermediate | 0.83 (0.44-1.55) | 1.31 (0.85-2.02) | 0.86 (0.63-1.17) | 1.03 (0.71-1.47) | 0.89 (0.62-1.28) | 0.54 (0.26-1.13) |
| High | 0.94 (0.48-1.83) | 1.09 (0.67-1.79) | 0.75 (0.53-1.08) | 0.84 (0.55-1.29) | 0.69 (0.45-1.06) | 0.38 (0.15-0.98) |
| P trend‡ | 0.85 | 0.71 | 0.12 | 0.45 | 0.09 | 0.04 |
NOTE: All models are stratified by age in years and adjusted for race, BMI, total caloric intake, number of comorbid conditions and estrogen receptor status.
↵*Nonlocalized stage of disease includes 1,008 regional and 66 metastatic; 28 women with unknown disease state were excluded from these stage specific analyses.
↵†Long-term strenuous and moderate activity summary variable classifies women with no activity >0.5 h/wk/y activity into the low group, those with at least one of moderate or strenuous activity >3 h/wk/y into the high group, and all others, that is, those with some activity that is >0.5 h/wk/y and ≤3 h/wk/y but not >3 hr/wk/y into the intermediate group.
↵‡P trend is the log-relative risk across categories (1, 2 and 3) of the strenuous-moderate summary variable.