Risk of breast cancer among female teachers of physical education and languages.
A retrospective follow-up study on 924 physical education (PE) and 3,239 language (L) teachers was performed to study whether life-long high physical activity affects the risk of breast cancer. The Finnish Cancer Registry found 128 malignant breast cancers among these women in a follow-up during 1967-1987. The standardized incidence ratio (SIR) for all PE teachers was 1.28 (n.s.) and for L teachers 1.59 (p less than 0.001). Before the menopause (below age 50) SIR for PE teachers was 0.93 (n.s.) and for L teachers 1.51 (p less than 0.05). These results suggest that before menopause the risk of breast cancer in physically active PE is smaller than in the less active L. A Poisson regression analysis, taking into account the reproductive factors together with age and observation period, did not show any significant difference between PE and L teachers, probably due to the relatively small number of cases (n = 22) in the PE teacher group.
Vihko
V J
VJ
LIKES-Research Center, Jyväskylä, Finland.
Apter
D L
DL
Pukkala
E I
EI
Oinonen
M T
MT
Hakulinen
T R
TR
Vihko
R K
RK
D000328:Adult; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000209:etiology; D015331:Cohort Studies; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D008037:Linguistics; D008875:Middle Aged; D010806:Physical Education and Training; D012189:Retrospective Studies; D012307:Risk Factors; D013663:Teaching