Study Links Alcohol and Smoking to Both Breast Cancer and Atrial Fibrillation in Older Women Worldwide

A new global analysis published in the Journal of the American Heart Association has identified alcohol use and smoking as common modifiable risk factors for both breast cancer and atrial fibrillation in women aged 55 and older. The study, which examined data from 204 countries and territories, found that in about 40% of regions, the rates of both conditions were similar, with the highest-risk zones in Western nations.

Researchers from Peking University People's Hospital analyzed data from the Global Burden of Disease 2021 database, focusing on women 55 years and older. They evaluated exposure to 58 risk factors, including smoking, alcohol use, body mass index, and physical activity. The study utilized machine learning to map global patterns and identify region-specific risk drivers.

Results showed that 80 countries (39%) had similar rates of both breast cancer and atrial fibrillation. Smoking and alcohol use were significantly linked to higher rates of both conditions. An additional analysis suggested that reducing alcohol intake and smoking could potentially lower the risk of breast cancer by about 15% and atrial fibrillation by about 12% worldwide. Alcohol use alone contributed to 9.27% of breast cancer cases and 7.57% of atrial fibrillation cases.

High-income nations such as the U.S., Canada, Australia, New Zealand, and much of Europe exhibited elevated rates of both conditions, aligning with previous research linking Western diets and sedentary lifestyles to increased risks. "One of the most surprising aspects of our findings was how common both breast cancer and atrial fibrillation diagnoses were among women ages 55 and older in high-income regions, which highlights the influence of lifestyle," said study co-author Shu Wang, M.D., Ph.D., director of the Breast Disease Center at Peking University People's Hospital.

The study's spatial risk maps can help guide region-specific prevention strategies. According to the researchers, the next steps include incorporating long-term research, genetic and metabolic data, and expanding the study to include socioeconomic factors. "Nowadays, more and more people are paying attention to the link between cancer and cardiovascular health," said co-authors Zeye Liu, M.D., Ph.D., and Yi Shi, M.D., Ph.D., both from Peking University People's Hospital. "Breast cancer and atrial fibrillation rise together across many regions of the world and share the same modifiable risk factors."

Laxmi Mehta, M.D., FAHA, chair of the American Heart Association's Council on Clinical Cardiology, who was not involved in the study, commented: "Many of the same modifiable factors, including smoking, alcohol use, poor diet, physical inactivity and obesity, contribute to both breast cancer and cardiovascular disease including atrial fibrillation, as confirmed by this study's findings. This overlap underscores the importance of integrated lifestyle strategies to reduce risk." The American Heart Association's Life's Essential 8 highlights key behaviors and health factors essential for prevention.

The study was published in the Journal of the American Heart Association, an open access, peer-reviewed journal. The findings are limited by the use of country-level data, which cannot prove direct cause and effect, and potential differences in screening and diagnostic criteria across regions.