Abstract 553P
Background
Breast cancer survivors are at increased risk of diabetes mellitus (DM), particularly in the early years post-treatment. This study examines short- and long-term DM risk by treatment methods and lifestyle factors.
Methods
Using Korean Health Insurance Service data, the study included 65,982 women newly diagnosed with invasive breast cancer (2010-2016). The primary outcome was DM, defined as individuals receiving diabetic medications. Sub-distribution hazard ratios (sHR) and 95% confidence intervals (CI) were estimated using competing risk analysis considering death.
Results
I In patients under 50, DM risk was significantly higher in the first year (sHR 3.742, 95% CI 3.078-4.548). The 1-year landmark analysis showed a smaller increase (sHR 1.106, 95% CI 1.032-1.186), but no significant increase after three years. Patients over 50 had increased DM risk during the first year (sHR 1.711, 95% CI 1.921-2.352), with no significant increase in later years. BMI ≥ 25 (sHR 1.449, 95% CI 1.318-1.594), current smoking (sHR 1.715, 95% CI 1.492-1.972), hypertension (sHR 1.476, 95% CI 1.367-1.593), and dyslipidemia (sHR 1.49, 95% CI 1.377-1.612) were all associated with increased DM risk across all age groups. Patients receiving taxane had higher DM risk regardless of age (sHR 1.148, 95% CI 1.062-1.242). Among those on endocrine therapy, only patients under 50 treated with tamoxifen had a significant DM risk increase (sHR 1.217, 95% CI 1.061-1.395).
Conclusions
DM risk increased in patients under 50 during the first three years, while patients over 50 showed increased risk only in the first year. Higher DM risk was also observed in those with high BMI, smoking, hypertension, dyslipidemia, or treated with taxane or tamoxifen.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.