Body composition and breast cancer in postmenopausal women: a Danish prospective cohort study.
OBJECTIVE
To assess the importance of body fat mass (BFM) and fat free mass (FFM) for the established positive association between BMI and breast cancer among post-menopausal women.


METHODS
A prospective cohort of 23,788 postmenopausal women included in the Danish study Diet, Cancer, and Health during 1993 to 1997 was linked to the Danish Cancer Registry to identify all cases of breast cancer occurring during 1993 to 2002. Breast cancer incidence rate ratios for anthropometric measurements with adjustment for known risk factors for breast cancer were calculated by Cox regression analyses.


RESULTS
Among the most commonly used anthropometric measurements, BMI was positively associated with breast cancer among never users of hormone replacement therapy (HRT). By splitting BMI into two indices, BFM index and FFM index, we found that the incidence rate ratio with each 1 kg/m(2) among never users of HRT was 0.98 (95% confidence interval, 0.93 to 1.03) for BFM index and 1.12 (95% confidence interval, 1.00 to 1.26) for FFM index after mutual adjustment.


CONCLUSIONS
The finding for BMI was in accordance with previous findings. Our results indicate that the FFM component of BMI may play a role for development of breast cancer among never users of HRT.
Mellemkjaer
Lene
L
Institute of Cancer Epidemiology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen Ø, Denmark. lene@cancer.dk
Bigaard
Janne
J
Tjønneland
Anne
A
Christensen
Jane
J
Thomsen
Birthe
B
Johansen
Christoffer
C
Overvad
Kim
K
Olsen
Jørgen H
JH
D000273:Adipose Tissue / Q000378:metabolism; D050154:Adiposity / Q000502:physiology; D000428:Alcohol Drinking; D001823:Body Composition / Q000502:physiology*; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000453:epidemiology / Q000378:metabolism / Q000503:physiopathology*; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D004522:Educational Status; D005260:Female; D020249:Hormone Replacement Therapy / Q000706:statistics & numerical data; D006801:Humans; D008875:Middle Aged; D010298:Parity; D017698:Postmenopause / Q000502:physiology*; D011247:Pregnancy; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012042:Registries / Q000706:statistics & numerical data