Table 4

Relative risk (RR) and 95% confidence intervals (CI) for the association of light physical activity during four periods of life with breast cancer incidence: 118,899 postmenopausal women in the NIH-AARP Diet and Health Study

Light activity

No.

cancers*

n = 4287

RR

95%

CI

RR††

95%

CI

RR§

95%

CI

RR£

95%

CI


Ages 15-18 years

Never/Rarely

358

1.00 (ref.)

1.00 (ref.)

1.00 (ref.)

1.00 (ref.)

<1 hour/week

344

1.09

0.94, 1.27

1.09

0.94

1.26

1.07

0.92

1.24

1.09

0.94

1.26

1-3 hours/week

974

1.06

0.94, 1.20

1.05

0.93

1.19

1.04

0.92

1.18

1.05

0.93

1.18

4-7 hours/week

982

1.08

0.96, 1.22

1.08

0.95

1.22

1.07

0.95

1.22

1.07

0.95

1.21

>7 hours/week

1553

1.03

0.92, 1.16

1.05

0.94

1.18

1.05

0.93

1.19

1.04

0.93

1.17

Ages 19-29 years

Never/Rarely

199

1.00 (ref.)

1.00 (ref.)

1.00 (ref.)

1.00 (ref.)

<1 hour/week

249

1.18

0.98, 1.42

1.16

0.97

1.40

1.15

0.95

1.38

1.16

0.96

1.40

1-3 hours/week

793

1.14

0.98, 1.34

1.11

0.95

1.30

1.10

0.94

1.29

1.11

0.95

1.30

4-7 hours/week

1036

1.13

0.97, 1.32

1.12

0.96

1.30

1.11

0.95

1.30

1.11

0.96

1.30

>7 hours/week

1940

1.05

0.91, 1.21

1.07

0.93

1.24

1.07

0.92

1.25

1.07

0.92

1.24

Ages 35-39 years

Never/Rarely

171

1.00 (ref.)

1.00 (ref.)

1.00 (ref.)

1.00 (ref.)

<1 hour/week

238

1.19

0.98, 1.44

1.17

0.96

1.42

1.14

0.94

1.40

1.16

0.95

1.41

1-3 hours/week

811

1.19

1.01, 1.41

1.15

0.98

1.36

1.15

0.97

1.36

1.15

0.98

1.36

4-7 hours/week

1036

1.08

0.92, 1.27

1.05

0.89

1.24

1.04

0.88

1.23

1.05

0.91

1.24

>7 hours/week

1952

1.05

0.90, 1.23

1.06

0.90

1.24

1.06

0.90

1.24

1.06

0.91

1.24

Past 10 years

Never/Rarely

183

1.00 (ref.)

1.00 (ref.)

1.00 (ref.)

1.00 (ref.)

<1 hour/week

266

1.23

1.02, 1.48

1.21

1.00

1.46

1.19

0.98

1.44

1.21

1.00

1.46

1-3 hours/week

890

1.13

0.96, 1.32

1.08

0.92

1.27

1.10

0.93

1.29

1.09

0.93

1.28

4-7 hours/week

1264

1.20

1.02, 1.40

1.14

0.98

1.34

1.19

1.01

1.39

1.16

0.99

1.36

>7 hours/week

1634

1.04

0.89, 1.21

1.01

0.87

1.18

1.09

0.92

1.28

1.04

0.89

1.21


* Number of cancer cases may not add up to total (n = 4287) due to missing physical activity values

† Relative risks adjusted for age (continuous)

†† Relative risks adjusted for: age (continuous); race/ethnicity (white, black, Hispanic, Asian/Pacific Islander/American Indian); education level (<12 years or high school equivalent, 12 years or high school equivalent, post-high school vocational or technical training, some college, college graduate, post-graduate); smoking status (non-smoker, former, current); alcohol intake (grams/day, quintiles adjusted for total energy intake); family history of breast cancer (no, yes); age at menarche (<13, 13-14, ≥ 15 years); age at first birth (nulliparous, <20, 20-24, 25-29, 30+ years); parity (number of children: 0, 1-2, 3 or more); age at menopause (<40, 40-44, 45-49, 50-54, ≥ 55 years); menopausal hormone use (never, ever)

§Relative risks additionally adjusted for frequency of other type of physical activity (either light or moderate-to-vigorous) during that same time period

£ Relative risks additionally adjusted for body mass index (BMI: <25.0, 25.0-29.9, 30.0-34.9, ≥ 35.0 kg/m2)

Peters et al. BMC Cancer 2009 9:349   doi:10.1186/1471-2407-9-349

Open Data