Alzheimer's risk may be signaled years earlier by four types of health conditions.

Researchers analyzed de-identified electronic health records from MarketScan and Vanderbilt and identified about 70 medical conditions across four categories that appeared in the decade before an Alzheimer's diagnosis.

Researchers report that four broad types of medical conditions were associated with later development of Alzheimer's disease. The study used de-identified electronic health records from two independent U.S. databases to search for medical patterns appearing in the decade before diagnosis. The team identified roughly 70 individual disorders that appeared in both datasets. Lead author Xue Zhong described the inventory as a potential tool for earlier risk recognition and prevention-focused research. Key findings: - The discovery cohort was the MarketScan claims database, which contained 43,508 individuals with an Alzheimer's diagnosis and 419,455 age- and sex-matched controls; findings were validated in Vanderbilt Health's EHR dataset with 1,320 cases and 12,720 matched controls. - Records were analyzed over a 10-year window before diagnosis, and more than 70 medical conditions were found in both databases as preceding Alzheimer's disease. - The conditions grouped into four categories: mental health (for example, depression and severe neuropsychiatric symptoms such as paranoia/psychosis and suicidal ideation); neurologic and sleep-related (for example, insomnia, hypersomnia and sleep apnea); cardiovascular and circulatory (for example, essential hypertension, cerebral atherosclerosis and cerebral ischemia); and endocrine/metabolic (for example, type 2 diabetes). - The authors emphasized that associations in EHRs do not establish causation and reported an inverse association between cancer and Alzheimer's disease that replicated across both datasets. - The paper noted a projection that delaying the onset of Alzheimer's disease by five years could cut incidence in half, and the authors framed the results as a data-driven roadmap for earlier recognition and further prevention research. Summary: The study highlights a set of medical conditions that commonly appear in the decade before an Alzheimer's diagnosis and validates those patterns across two large U.S. datasets. The authors report ongoing work to investigate underlying mechanisms, including the inverse association with cancer, and to pursue prevention-focused research to clarify causal links and implications.