Summary
| Direction in Alzheimer's Disease and Other Dementias | ↑ Elevated — higher than in the comparison group |
|---|---|
| Category | Other |
| Compared against | healthy individuals |
| Associated symptoms | Alzheimer's disease and other dementias |
| Test type | Blood test (serum / plasma / whole blood) |
| LOINC code | 13965-9 |
| Source | Hoffman et al. 2011 — doi:10.1016/j.mehy.2011.09.009 |
| Condition atlas | Alzheimer's Disease and Other Dementias Biomarker Atlas |
Other conditions where Homocysteine is reported
- Homocysteine in Gulf War Illness — ↑ elevated vs HGV
- Homocysteine in Major Depressive Disorder — ↑ elevated vs normal reference range
- Homocysteine in Migraine — ↑ elevated vs controls
See the cross-condition hub: Homocysteine across conditions.
Related Other markers in Alzheimer's Disease and Other Dementias
Full list: Alzheimer's Disease and Other Dementias Biomarker Atlas.
Frequently asked questions
Is Homocysteine high or low in Alzheimer's Disease and Other Dementias?
Elevated. Studies summarised in the OSMF atlas report higher Homocysteine in Alzheimer's Disease and Other Dementias than in healthy individuals. Source: Hoffman et al. 2011.
What symptoms is Homocysteine associated with in Alzheimer's Disease and Other Dementias?
The cited literature associates this marker with Alzheimer's disease and other dementias. These are population-level associations and do not mean the marker causes the symptoms.
Which test measures Homocysteine?
It is measured as a blood test (serum / plasma / whole blood). The standard laboratory code is LOINC 13965-9. Many of the cited studies used research-grade assays, so clinical availability may vary.
Is one abnormal Homocysteine result diagnostic of Alzheimer's Disease and Other Dementias?
No. No single biomarker is diagnostic of Alzheimer's Disease and Other Dementias. Homocysteine findings come from group comparisons, overlap considerably between patients and controls, and vary with study design, timing and comparison group. A result should be interpreted by a clinician alongside symptoms, history and other tests.
Is Homocysteine specific to Alzheimer's Disease and Other Dementias?
No. The same marker is also reported in Gulf War Illness, Major Depressive Disorder, Migraine in this atlas, so it reflects shared biology (for example inflammation or vascular stress) rather than a condition-specific signature.
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Last reviewed: 2026-10-08 · Page generated from alzheimer-s-disease-and-other-dementias.json · Browse: Alzheimer's Disease and Other Dementias atlas · Biomarker Index · All marker pages
Disclaimer: This page is an educational synthesis of published, peer-reviewed research and is not medical advice. Biomarker findings vary across studies with case definitions, comparison groups, timing and assay methods. Direction of change reflects the predominant finding in the cited source and does not establish a diagnostic threshold. Discuss any test result with a qualified clinician.