Researchers Find Common Risk Factors Linking Breast Cancer and Atrial Fibrillation

A cigarette and a drink may be doing more harm than you think-raising the risk of both breast cancer and an irregular heartbeat.

Smoking and alcohol use are strongly linked to higher rates of both breast cancer and atrial fibrillation (AFib) in women aged 55 years and older, according to two independent analyses published in the Journal of the American Heart Association. Researchers say reducing these modifiable risk factors could help lower the global burden of both diseases.

The study analysed data from women aged 55 years and above across 204 countries and territories, examining exposure to 58 lifestyle, health and environmental risk factors. Researchers found that 39% of countries had similarly high rates of both breast cancer and AFib, while 32% were breast cancer-dominant and 28% were AFib-dominant.

After adjusting for multiple factors, smoking and alcohol consumption emerged as the strongest shared risk factors for both conditions. The researchers estimated that cutting alcohol intake and smoking could potentially reduce breast cancer cases by about 15% and atrial fibrillation/flutter by nearly 12% worldwide. Alcohol alone accounted for approximately 9.27% of breast cancer cases and 7.57% of AFib cases.

Researchers noted that this is the first study to combine global disease data with machine learning to identify geographical patterns and shared risk factors for breast cancer and AFib. They believe the findings could help shape region-specific prevention strategies.

However, the authors cautioned that the analysis was based on country-level data and cannot establish a direct cause-and-effect relationship. Future studies incorporating genetic, metabolic and socioeconomic data may help develop more personalised prevention strategies.

REFERENCE: Zhang, Y., et al. (2026) Global Geospatial Trends in Breast Cancer and Atrial Fibrillation/Flutter Among Older Women: Uncovering Shared Epidemiological Patterns and Etiological Links; Journal of the American Heart Association. DOI: 10.1161/JAHA.125.047762.