Urine Testing for Alzheimer's Disease

Two new tests for Alzheimer’s disease have received attention lately, both of which use urine samples to detect biochemical markers associated with this condition. The tests have slightly different purposes. The first, which is currently being marketed, is a diagnostic aid, while the other test, still in development, could be useful as a predictor of Alzheimer’s disease.

A major advantage of these tests is that they are non-invasive, requiring just a urine sample from the patient, unlike other testing methods used to help diagnose this disease, such as a spinal tap to collect cerebrospinal fluid for analysis of beta amyloid precursor and Tau proteins (see Tau/Aß42 Test).

Alzheimer’s disease is a fatal neurological disease that is fairly common in the U.S., primarily among the elderly, and causes cognitive impairment, including memory loss. It is a difficult disease to diagnose; currently, definite diagnoses can only be made through an analysis of brain tissue during an autopsy or brain biopsy. However, there is a new test that can aid in diagnosing and monitoring patients who are living with this disease.

It uses a first-morning urine sample and detects the level of a brain protein called neural thread protein (NTP). Studies have shown that elevation of this biochemical marker is associated with disease severity and progression. In helping to identify Alzheimer’s disease early on, this test will allow patients to receive available therapies when they can be most effective and before irreversible damage occurs.

It will probably be most useful as a confirmatory test in the diagnosis of Alzheimer’s, used in combination with other relevant medical data and physicians’ clinical assessment of patients’ symptoms.

The other test detects the biomarker isoprostane 8,12-iso-iPf2ª-VI, which is indicative of brain oxidative damage and is elevated in the spinal fluid, blood, and urine of patients with mild cognitive impairment (MCI), believed to be a precursor to Alzheimer’s disease. Researchers are hopeful that using a simple urine test for this biomarker among patients with MCI will help to identify those who are at increased risk for Alzheimer’s disease.

This would allow time to intervene with therapies that may slow the brain damage and cognitive decline that accompanies Alzheimer’s disease. Studies are ongoing and development of the urine test continues, with a product likely to be available for clinical use within two years.