Background: Breast cancer screening is crucial for early detection and improved survival in Alzheimer disease and related dementias (ADRD) patients, but real-world evidence of its effects on survival and prognosis remains insufficient.
Methods: We conducted a retrospective cohort study using Surveillance, Epidemiology, and End Results-Medicare data (1999-2019) to analyze the impact of breast cancer screening on prognosis (ie, cancer stage) and survival in ADRD women with breast cancer diagnosed at ages 67 years and older. Logistic and Cox regression models were employed to assess the relationship between screening and risk of advanced stage at diagnosis and length of survival, adjusted for relevant covariates (eg, marital status, comorbidities, age at screening).
Results: The cohort included 8739 ADRD patients with breast cancer, with 4483 completed at least 1 screening between their ADRD and first breast cancer diagnosis. The cohort completed screening had statistically significant lower rates of advanced-stage diagnosis (22.2% vs 42.6%) and longer survival (65.9 vs 45.7 months) compared with the cohort without any screening history. Unscreened patients had 2.7 times higher odds of advanced-stage diagnosis and 2 times higher hazard of death than patients with at least 1 screening completed before breast cancer diagnosis. Effects of comorbidities, age, and race were statistically significant on diagnosis stage and survival in breast cancer patients.
Conclusion: Our study demonstrated the benefit of screening in early diagnosis and longer survival in ADRD patients with breast cancer, which advocates for an expansion of current breast cancer screening recommendations to more effectively guide cancer care for ADRD patients.
© The Author(s) 2026. Published by Oxford University Press.