Why it should be "Alzheimer disease" rather than "Alzheimer's disease".

The terms "Alzheimer's disease" and "Alzheimer disease" are often used interchangeably in the biomedical literature. Yet this seemingly minor grammatical difference carries implications that extend beyond style: the possessive form, marked by the 's eponym, may imply ownership of a disease by an individual, a notion discouraged by several authoritative medical style guides and international health organizations [1]. In this article, we examine the historical emergence of the term "Alzheimer's disease", analyze the trajectories of the possessive and non-possessive eponyms in PubMed-indexed article titles from 1950 to 2025, and assess how the choice of terminology influences literature retrieval. Our analysis indicates that the possessive form has overwhelmingly dominated the literature for decades. However, searches using "Alzheimer's disease" or "Alzheimer disease" retrieve non-identical, only partially overlapping sets of records in PubMed. We argue that adopting the non-possessive form "Alzheimer disease" would improve conceptual clarity, terminological consistency, and the completeness of literature retrieval, particularly in systematic reviews and meta-analyses.