How does body mass index affect breast cancer risk in postmenopausal women with and without cardiovascular disease?

New research reveals that excess weight is linked to an especially high risk of developing breast cancer in postmenopausal women with cardiovascular disease. The findings are published by Wiley online in CANCER, a peer-reviewed journal of the American Cancer Society.

Although higher body mass index (BMI) is a known risk factor for breast cancer in postmenopausal women, it’s unclear whether this risk differs among women with and without cardiovascular disease or type 2 diabetes. To investigate, a team led by Heinz Freisling, PhD, of the International Agency for Research on Cancer (the specialized cancer agency of the World Health Organization) analyzed data from the European Prospective Investigation into Cancer and Nutrition (EPIC) and UK Biobank on 168,547 postmenopausal women who did not have, type 2 diabetes, and cardiovascular disease when they agreed to participate.

After a median follow-up of 10.7 years in EPIC and 10.9 years in UK Biobank, 6,793 postmenopausal women developed breast cancer. In a pooled analysis of both studies, each 5 kg/m2 increase in BMI was associated with a 31% higher risk of breast cancer in women who developed cardiovascular disease during follow-up and a 13% higher risk in women without cardiovascular disease. The development of type 2 diabetes did not seem to affect breast cancer risk: women with or without type 2 diabetes had a similarly elevated breast cancer risk related to higher BMI.

The combination of overweight (BMI≥25 kg/m2) and cardiovascular disease was estimated to lead to 153 more cases of breast cancer per 100,000 people per year than expected.

“The findings of this study could be used to inform risk-stratified breast cancer screening programs,” said Dr. Freisling. “This study should also inspire future research to include women with a history of cardiovascular diseases in weight loss trials for breast cancer prevention.” 

“These findings could help to identify women at a higher risk of postmenopausal breast cancer" said Dr. Julia Panina, Head of Research Funding at World Cancer Research Fund. "The results support our Cancer Prevention Recommendation to be a healthy weight, which could be of particular benefit to women with cardiovascular disease. This research supports World Cancer Research Fund’s ongoing efforts to understand how lifestyle factors interact to influence cancer risk and to tailor prevention strategies accordingly.”

Additional information

Full Citation:
“Body mass index and breast cancer risk among postmenopausal women with and without cardiometabolic diseases: findings from two prospective cohort studies in Europe.” Emma Fontvieille, Anna Jansana, Laia Peruchet-Noray, Reynalda Córdova, Quan Gan, Sabina Rinaldi, Laure Dossus, Yahya Mahamat-Saleh, Marc J. Gunter, Alicia Heath, Dagfinn Aune, Elif Inan-Eroglu, Matthias B. Schulze, Niels Bock, Christina C. Dahm, Carlota Castro-Espin, Maria-José Sánchez, Aurora Perez-Cornago, Sandar Tin Tin, Sabina Sieri, Vittorio Simeon, Fulvio Ricceri, Rosario Tumino, N. Charlotte Onland-Moret, Yvonne Koop, Pietro Ferrari, and Heinz Freisling. CANCER; Published Online: July 7, 2025 (DOI: 10.1002/cncr.35911).
URL: http://doi.wiley.com/10.1002/cncr.35911

Funding: Funding was obtained from World Cancer Research Fund (UK), as part of the World Cancer Research Fund International grant program.

About the Journal     
CANCER is a peer-reviewed publication of the American Cancer Society integrating scientific information from worldwide sources for all oncologic specialties. The objective of CANCER is to provide an interdisciplinary forum for the exchange of information among oncologic disciplines concerned with the etiology, course, and treatment of human cancer. CANCER is published on behalf of the American Cancer Society by Wiley and can be accessed online. Follow CANCER on X @JournalCancer and Instagram @ACSJournalCancer, and stay up to date with the American Cancer Society Journals on LinkedIn.

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