Environment and Breast Cancer: Science Review
About
Breast cancer risk and lifetime leisure-time and occupational physical activity (Sweden)
Moradi, T.,, Nyren, O.,, Zack, M.,, Magnusson, C.,, Persson, I.,, Adami, H. O. Cancer Causes and Control. 2000. 11, 523-531.
Topic area
Physical Activity - Body size
Physical Activity - Body size
Study design
Population based case-control
Population based case-control
Funding agency
NCI
NCI
Study Participants
Number of Cases
2838 (invasive only)
2838 (invasive only)
Menopausal Status
The menopausal status of women included in this study is listed here.
Post menopausal
Number of Controls
Controls: 3108
Controls: 3108
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
In: Residents of Sweden age 50-74; diagnosed with invasive breast cancer between 10/93 and 3/95; postmenopausal (cases); women in the Swedish population registry (cases)
Ex: women with a previous diagnosis of invasive breast cancer; women with an unknown menopausal status; premenopausal women
Comment about participation selection
Strengths: population based case-control study; high participation rate; assessed physical activity during different periods of life; large number of cases; analyzed breast cancer risk by occupational physical activity and stratified results by BMI and parity Limitations: self administered questionnaire; self-reported physical activity and anthropometric data; occupational physical activity were coded according to classification
Strengths: population based case-control study; high participation rate; assessed physical activity during different periods of life; large number of cases; analyzed breast cancer risk by occupational physical activity and stratified results by BMI and parity Limitations: self administered questionnaire; self-reported physical activity and anthropometric data; occupational physical activity were coded according to classification
Exposure Investigated
Exposures investigated
Lack of leisure-time and occupational physical activity, BMI
Lack of leisure-time and occupational physical activity, BMI
How exposure was measured
Questionnaire, self-administered Questionnaire, by telephone (only 14% of controls)
Questionnaire, self-administered Questionnaire, by telephone (only 14% of controls)
Exposure assessment comment
Self-reported physical activity and anthropometric data, occupational physical activity were coded according to classification
Self-reported physical activity and anthropometric data, occupational physical activity were coded according to classification
Early life exposures considered
Physical activity during childhood
Physical activity during childhood
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: age at menarche, parity, age at first birth, age at menopause, HRT use, height, BMI, OC use, smoking status, alcohol, family history of breast cancer, history of benign breast disease
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: BMI and parity
Effect modifiers: BMI and parity
Strength of associations reported
Association between postmenopausal breast cancer risk and 1-2 hours of recreational physical activity vs > 2 hours of activity during childhood, age 18-30 and during baseline years, OR=1.3(1.1-1.5), OR=1.4(1.3-1.6), OR=1.3(1.2-1.5) respectively.
Association between postmenopausal breast cancer risk and a sedentary occupational physical activity level vs a high/very high occupational physical activity level in women age 25-44 years, OR=1.6(1.1-2.3)
Association between postmenopausal breast cancer risk and a sedentary occupational physical activity level vs a high/very high occupational physical activity level in women with a BMI of <23.5, OR=2.2(1.1-4.3)
Association between postmenopausal breast cancer risk and a sedentary occupational physical activity level vs a high/very high occupational physical activity level in nulliparous women, OR=2.8(1.2-6.5)
Women sedentary both at work and at leisure during their reproductive years (25-44 yrs) had a three-fold excess risk of post breast cancer compared to that in the most active women, OR=3.1(1.3-7.7)
Association between postmenopausal breast cancer risk and 1-2 hours of recreational physical activity vs > 2 hours of activity during childhood, age 18-30 and during baseline years, OR=1.3(1.1-1.5), OR=1.4(1.3-1.6), OR=1.3(1.2-1.5) respectively.
Association between postmenopausal breast cancer risk and a sedentary occupational physical activity level vs a high/very high occupational physical activity level in women age 25-44 years, OR=1.6(1.1-2.3)
Association between postmenopausal breast cancer risk and a sedentary occupational physical activity level vs a high/very high occupational physical activity level in women with a BMI of <23.5, OR=2.2(1.1-4.3)
Association between postmenopausal breast cancer risk and a sedentary occupational physical activity level vs a high/very high occupational physical activity level in nulliparous women, OR=2.8(1.2-6.5)
Women sedentary both at work and at leisure during their reproductive years (25-44 yrs) had a three-fold excess risk of post breast cancer compared to that in the most active women, OR=3.1(1.3-7.7)
Controls participation rate
Greater than 70%
Greater than 70%