Table 6.

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
        Low1.001.001.001.001.001.00
        Intermediate0.48 (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)
        High0.35 (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 trend0.0080.040.150.070.780.74
Recent physical activity
    Combined
        Low1.001.001.001.001.001.00
        Intermediate0.83 (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)
        High0.94 (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 trend0.850.710.120.450.090.04

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.