An observational study in Breast Cancer, sponsored by Brigham and Women's Hospital. Completed at 1 site in United States. Open to participants aged 65 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-07-28.
Sponsored by Brigham and Women's Hospital · Observational
This study aims to evaluate the comparative risk of dementia/Alzheimer's disease onset between patients treated with medications that target specific metabolic pathways and patients treated with alternative medications for the same indication.
This is a non-randomized, non-interventional study that is part of the DREAM Study of Brigham and Women's Hospital. DREAM is led by Dr. Madhav Thambisetty, MD, PhD, Chief of the Clinical and Translational Neuroscience Section, Laboratory of Behavioral Neuroscience, National Institute on Aging (NIA) intramural research program. This study aims to evaluate the comparative risk of dementia/Alzheimer's disease onset between patients treated with medications that target specific metabolic pathways and patients treated with alternative medications for the same indication using healthcare claims data.
12,544 studies on the registry are indexed under Breast Neoplasms; 2,892 are open to participants now.
This study's enrollment of 16,989 is above the median of 184 across 2,642 observational studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Brigham and Women's Hospital is the lead sponsor of 1,236 studies on the registry; 224 are open to participants now.
Of its 116 completed or terminated interventional studies of FDA-regulated products, 64 (55%) have results posted.
Counted across the registry records on this site, refreshed daily.
This study will employ a new user, active comparator, observational cohort study design comparing Anastrozole vs Exemestane/Letrozole. The patients will be required to have continuous enrollment during the baseline period of 365 days before initiation of study drugs (cohort entry/index date). Follow-up for the outcome (dementia) differs between analyses. Follow-up begins the day after drug initiation (analysis 1, 3, 4); 180 days after drug initiation (analysis 2).
Please see https://docs.google.com/spreadsheets/d/1GrnVsPCockqqdfxC9LWd6ndbzS2wpJVvTbCOAhn4DLM/edit?usp=sharing or Appendix A (https://drive.google.com/drive/folders/1I8FVmpPzC5wQN9DFIv1Rbwh1N0SLEv0B?usp=sharing) for full code and algorithm definitions.
Medicare timeframe: 2008 to 2018 (end of data availability)
Inclusion Criteria:
Exclusion Criteria:
Exposure group
Drug: Anastrozole
Reference group
Drug: Exemestane/Letrozole
Anastrozole claim is used as the exposure group.
Exemestane/Letrozole claim is used as the reference group.
Time to dementia onset
Time to dementia onset, i.e., Alzheimer's disease, vascular dementia, senile, presenile, or unspecified dementia, or dementia in other diseases classified elsewhere. Please refer to uploaded protocol for full definition due to size limitations.
Time frame: up to 6 years
Time to Alzheimer's disease onset
Time to Alzheimer's disease onset. Please refer to uploaded protocol for full definition due to size limitations.
Time frame: up to 6 years
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This study is completed, as verified in Jul 2025. You cannot join it, but the record below documents what was studied.
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Brigham and Women's Hospital