Table 2.
Hazard ratios and 95% confidence intervals for associations of recreational physical activity and outcomes after first invasive breast cancer diagnosis in the Prospective Family Study Cohort
| Categorization of RPA | All-cause mortality (n = 4610) |
Second breast cancer event (n = 4356) |
||||||
|---|---|---|---|---|---|---|---|---|
| No. of women | No. of events | Person-years | HR (95% CI)a | No. of women | No. of events | Person-years | HR (95% CI)a | |
| RPA categorized as any vs none | ||||||||
| None | 750 | 226 | 7541 | 1.00 (Referent) | 720 | 67 | 6981 | 1.00 (Referent) |
| Any | 3860 | 986 | 43 331 | 0.84 (0.72 to 0.98) | 3636 | 406 | 38 609 | 1.05 (0.81 to 1.38) |
| RPA categorized by intensity level | ||||||||
| None | 750 | 226 | 7541 | 1.00 (Referent) | 720 | 67 | 6981 | 1.00 (Referent) |
| Moderate RPA only | 1737 | 446 | 20 025 | 0.82 (0.70 to 0.97) | 1646 | 193 | 18 007 | 1.17 (0.88 to 1.56) |
| Strenuous RPA | 2123b | 540 | 23 306 | 0.86 (0.73 to 1.02) | 1990c | 213 | 20 602 | 0.93 (0.69 to 1.24) |
| RPA categorized by national and international guidelinesd | ||||||||
| None | 750 | 226 | 7541 | 1.00 (Referent) | 720 | 67 | 6981 | 1.00 (Referent) |
| Some, but less than guidelinese | 1045 | 263 | 11 949 | 0.83 (0.69 to 0.99) | 992 | 108 | 10 764 | 1.12 (0.82 to 1.53) |
| Met guidelinesf | 1581 | 431 | 17 282 | 0.87 (0.73 to 1.03) | 1505 | 184 | 15 522 | 1.10 (0.82 to 1.47) |
| Exceeded guidelinesg | 1234 | 292 | 14 100 | 0.81 (0.67 to 0.98) | 1 to139 | 114 | 12 to323 | 0.92 (0.67 to 1.27) |
| RPA categorized by quintiles of total metabolic equivalents | ||||||||
| < 4 MET-hrs/wk | 857 | 250 | 8839 | 1.00 (Referent) | 821 | 79 | 8140 | 1.00 (Referent) |
| 4-11 MET-hrs/wk | 910 | 231 | 10 267 | 0.88 (0.73 to 1.06) | 865 | 92 | 9255 | 1.09 (0.81 to 1.49) |
| 12-20 MET-hrs/wk | 1193 | 325 | 12 959 | 0.92 (0.78 to 1.10) | 1133 | 135 | 11 653 | 1.05 (0.79 to 1.40) |
| 21-34 MET-hrs/wk | 781 | 210 | 8771 | 0.88 (0.73 to 1.07) | 738 | 84 | 7846 | 0.98 (0.71 to 1.34) |
| > 34 MET-hrs/wk | 869 | 196 | 10 036 | 0.83 (0.68 to 1.01) | 799 | 83 | 8696 | 0.94 (0.68 to 1.31) |
| Ptrendh across quintiles of MET-hrs/wk | .13 | .45 | ||||||
Hazard ratio and 95% confidence interval adjusted for age group at diagnosis (younger than 40, 40-49, 50-59, 60 years or older), study center (Australia, Canada, kConFab, New York, Northern California, Philadelphia, Utah), decade of birth year (<1950, 1950-1959, 1960-1969, ≥1970), race and ethnicity (Asian, Hispanic, non-Hispanic Black, non-Hispanic White, other), education (high school graduate or less, some college, Bachelor degree or higher), cigarette smoking (never, former, current), alcohol consumption (never, former, current), postmenopausal hormone therapy use (never vs otherwise), body mass index (<25, 25 to <30, ≥30 kg/m2), stage at diagnosis (1, 2, 3 or 4, unknown), chemotherapy for first invasive breast cancer (yes vs otherwise) radiation treatment for first invasive breast cancer (yes vs otherwise), and surgery for first invasive breast cancer (mastectomy, lumpectomy, otherwise). CI = confidence interval; HR = hazard ratio; MET = metabolic equivalents; RPA = recreational physical activity.
Includes 106 women who engaged in only strenuous RPA and 2017 women who engaged in strenuous and moderate RPA.
Includes 100 women who engaged in only strenuous RPA and 1890 who engaged in strenuous and moderate RPA.
Based on the Physical Activity Guidelines for Americans (2018) and the World Health Organization’s 2020 Physical Activity Guidelines, which recommend adults engage in 150-300 minutes per week of moderate physical activity or 75-150 minutes per week of strenuous physical activity, or some combination.
Less than 150 minutes per week of moderate RPA and less than 75 minutes per week of strenuous RPA.
150-300 minutes per week of moderate RPA or 75-150 minutes per week of strenuous RPA.
>300 minutes per week of moderate or >150 minutes per week of strenuous RPA.
P value reported from 2-sided Wald test.