OBJECTIVES: To investigate associations between physical activity and endogenous sex hormones after menopause with a special focus on confounding and effect modification by body mass index (BMI). METHODS: A cross-sectional study among 1,260 postmenopausal women was conducted. Generalized linear models were used to compare levels of total leisure-time physical activity, sports activities, bicycling, and walking with levels of sex hormones and sex-hormone-binding-globulin (SHBG). RESULTS: Higher sports activity levels were significantly associated with lower levels of estrone and total and free testosterone in multivariate adjusted models. After additional adjustment for BMI, associations with estrone and free testosterone were attenuated; the association with total testosterone remained unchanged. No physical activity variable was significantly related to total and free estradiol, androstenedione, or SHBG. We did not observe effect modification by BMI. CONCLUSIONS: Sports activities may lead to lower levels of estrone and testosterone in postmenopausal women. While effects on estrone and free testosterone seem to be largely mediated by BMI, effects on total testosterone appear to be mainly independent of BMI. The BMI-independent effects on these hormones (especially on total testosterone) could at least partly explain why physical activity has been frequently reported to be preventive for postmenopausal breast cancer, even after accounting for BMI.
OBJECTIVES: To investigate associations between physical activity and endogenous sex hormones after menopause with a special focus on confounding and effect modification by body mass index (BMI). METHODS: A cross-sectional study among 1,260 postmenopausal women was conducted. Generalized linear models were used to compare levels of total leisure-time physical activity, sports activities, bicycling, and walking with levels of sex hormones and sex-hormone-binding-globulin (SHBG). RESULTS: Higher sports activity levels were significantly associated with lower levels of estrone and total and free testosterone in multivariate adjusted models. After additional adjustment for BMI, associations with estrone and free testosterone were attenuated; the association with total testosterone remained unchanged. No physical activity variable was significantly related to total and free estradiol, androstenedione, or SHBG. We did not observe effect modification by BMI. CONCLUSIONS: Sports activities may lead to lower levels of estrone and testosterone in postmenopausal women. While effects on estrone and free testosterone seem to be largely mediated by BMI, effects on total testosterone appear to be mainly independent of BMI. The BMI-independent effects on these hormones (especially on total testosterone) could at least partly explain why physical activity has been frequently reported to be preventive for postmenopausal breast cancer, even after accounting for BMI.
Authors: Marquis Hawkins; Deirdre K Tobias; Hala B Alessa; Andrea K Chomistek; Junaidah B Barnett; Walter C Willett; Susan E Hankinson Journal: J Phys Act Health Date: 2019-04-11
Authors: Marc J Gunter; Neil Murphy; Nikos Papadimitriou; Niki Dimou; Konstantinos K Tsilidis; Barbara Banbury; Richard M Martin; Sarah J Lewis; Nabila Kazmi; Timothy M Robinson; Demetrius Albanes; Krasimira Aleksandrova; Sonja I Berndt; D Timothy Bishop; Hermann Brenner; Daniel D Buchanan; Bas Bueno-de-Mesquita; Peter T Campbell; Sergi Castellví-Bel; Andrew T Chan; Jenny Chang-Claude; Merete Ellingjord-Dale; Jane C Figueiredo; Steven J Gallinger; Graham G Giles; Edward Giovannucci; Stephen B Gruber; Andrea Gsur; Jochen Hampe; Heather Hampel; Sophia Harlid; Tabitha A Harrison; Michael Hoffmeister; John L Hopper; Li Hsu; José María Huerta; Jeroen R Huyghe; Mark A Jenkins; Temitope O Keku; Tilman Kühn; Carlo La Vecchia; Loic Le Marchand; Christopher I Li; Li Li; Annika Lindblom; Noralane M Lindor; Brigid Lynch; Sanford D Markowitz; Giovanna Masala; Anne M May; Roger Milne; Evelyn Monninkhof; Lorena Moreno; Victor Moreno; Polly A Newcomb; Kenneth Offit; Vittorio Perduca; Paul D P Pharoah; Elizabeth A Platz; John D Potter; Gad Rennert; Elio Riboli; Maria-Jose Sánchez; Stephanie L Schmit; Robert E Schoen; Gianluca Severi; Sabina Sieri; Martha L Slattery; Mingyang Song; Catherine M Tangen; Stephen N Thibodeau; Ruth C Travis; Antonia Trichopoulou; Cornelia M Ulrich; Franzel J B van Duijnhoven; Bethany Van Guelpen; Pavel Vodicka; Emily White; Alicja Wolk; Michael O Woods; Anna H Wu; Ulrike Peters Journal: Nat Commun Date: 2020-01-30 Impact factor: 14.919