Environment and Breast Cancer: Science Review
About
Physical activity and the risk of breast cancer: a case-control study of Japanese women
Ueji, M.,, Ueno, E.,, Osei-Hyiaman, D.,, Takahashi, H.,, Kano, K. Journal of Epidemiology. 1999. 8, 116-122.
Topic area
Physical Activity
Physical Activity
Study design
Other: matched case-control
Other: matched case-control
Funding agency
Not reported
Not reported
Study Participants
Number of Cases
148 (80 pre) (59 post)
148 (80 pre) (59 post)
Menopausal Status
Post menopausal
The menopausal status of women included in this study is listed here.
Pre menopausalPost menopausal
Number of Controls
Control: 236 (109 pre) (127 post)
Control: 236 (109 pre) (127 post)
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
In: women diagnosed with breast cancer at Tsukuba University Hospital or Tsukuba Medical Center Hospital between January 1990 and March 1997 (cases); residents of Ibaraki Prefecture; less than 70 years at diagnosis (cases); age and residence matched to cases (controls)
Ex: cases without matched pairs; women with a history of breast cancer
Comment about participation selection
Strengths: all cases were histologically confirmed; obtained information on the type, frequency and duration of exercises performed by participants; analyzed physical activity using METs (metabolic equivalents); analyzed breast cancer risk by physical activity stratified by menopausal status Limitations: used a self-administered questionnaire; physical activity and anthropometric data were self-reported; low participation rate amongst controls; few cases, especially after results were stratified by menopausal status; did not assess adolescent physical activity; quantified occupational physical activity with a work index
Strengths: all cases were histologically confirmed; obtained information on the type, frequency and duration of exercises performed by participants; analyzed physical activity using METs (metabolic equivalents); analyzed breast cancer risk by physical activity stratified by menopausal status Limitations: used a self-administered questionnaire; physical activity and anthropometric data were self-reported; low participation rate amongst controls; few cases, especially after results were stratified by menopausal status; did not assess adolescent physical activity; quantified occupational physical activity with a work index
Exposure Investigated
Exposures investigated
Physical inactivity
Physical inactivity
How exposure was measured
Questionnaire, self-administered
Questionnaire, self-administered
Exposure assessment comment
Physical activity and anthropometric data were self-reported
Physical activity and anthropometric data were self-reported
Statistical Analysis
Breast cancer outcome investigated
Primary breast cancer
Primary breast cancer
Ethnic groups with separate analysis
If this study provided a separate analysis by ethnic or racial group, the groups are listed here.
No
Confounders considered
Other breast cancer risk factors, such as family history, age at first birth, and hormone replacement therapy use, that were taken into account in the study.
Adequately controlled, confounders: family history of breast cancer, education, age at menarche, age at first childbirth, parity, menopausal status, height, BMI
Genetic characterization included
If the study analyzed relationships between environmental factors and inherited genetic variations, this field will be marked “Yes.” “No”, if not.
No
Description of major analysis
Effect modifiers: menopausal status
Effect modifiers: menopausal status
Strength of associations reported
Inverse association between breast cancer and recreational physical activity, >15.3 (METs/wk) vs. none, OR=0.35(0.17-0.73) trend p=0.005
Inverse association between breast cancer and recreational physical activity, >15.3 (METs/wk) vs. none, OR=0.35(0.17-0.73) trend p=0.005
Results Comments
No association between breast cancer and occupational physical activity, highest vs. lowest quartile, OR=0.55(0.27-1.12) trend p=0.223 No association between premenopausal breast cancer and recreational physical activity, >15.3 (METs/wk) vs. none , OR= 0.32(0.10-1.03) trend p=0.075 No association between premenopausal breast cancer and occupational physical activity, highest vs. lowest quartile, OR=0.60(0.16-2.28) trend p=0.680 No association between postmenopausal breast cancer and recreational physical activity, >15.3 (METs/wk) vs. none , OR= 0.49(0.14-1.63) trend p=0.231 No association between postmenopausal breast cancer and occupational physical activity, highest vs. lowest quartile, OR=0.65(0.22-1.94) trend p=0.464
No association between breast cancer and occupational physical activity, highest vs. lowest quartile, OR=0.55(0.27-1.12) trend p=0.223 No association between premenopausal breast cancer and recreational physical activity, >15.3 (METs/wk) vs. none , OR= 0.32(0.10-1.03) trend p=0.075 No association between premenopausal breast cancer and occupational physical activity, highest vs. lowest quartile, OR=0.60(0.16-2.28) trend p=0.680 No association between postmenopausal breast cancer and recreational physical activity, >15.3 (METs/wk) vs. none , OR= 0.49(0.14-1.63) trend p=0.231 No association between postmenopausal breast cancer and occupational physical activity, highest vs. lowest quartile, OR=0.65(0.22-1.94) trend p=0.464
Controls participation rate
Less than 70% (66%)
Less than 70% (66%)