I read about experimental Alzheimer's tests that can detect early stages of the disease. Are these really helpful?

Answers from Ronald Petersen, M.D.

An important first step in developing a treatment plan for any disease is having a clear diagnosis. New Alzheimer's tests may help with early detection of some of the pathological components of the disease. However, before these become widely available, more research is needed to determine who might benefit from them and what they reveal about the progression of Alzheimer's and other diseases.

  • Biomarker test. Researchers have proposed Alzheimer's tests that measure two proteins, beta–amyloid and tau, in cerebrospinal fluid. The fluid is examined for evidence of abnormal development of beta-amyloid proteins, which form plaques, and tau proteins, which form tangles. Both plaques and tangles are thought to contribute to the development of Alzheimer's disease. These proteins can help identify people with the underlying disease process who are likely to progress to more–serious forms of the disease.
  • Brain imaging (neuroimaging). Brain imaging — using equipment to record images of changes in the brain — is another area of research. Researchers are studying imaging techniques, such as magnetic resonance imaging (MRI) and positron emission tomography (PET) scans, used in conjunction with radiotracers. These radiotracers are charged particles that "light up" Alzheimer's-affected areas in images of the brain — for example, by attaching to proteins, amyloid and tau, associated with Alzheimer's disease.
  • Cognitive assessment. Technology is also being used to develop software for computer–based assessments that detect cognitive changes and may be useful in the early diagnosis of Alzheimer's disease.

Early detection and diagnosis of Alzheimer's disease is an important goal. Early intervention with medications may slow the progression of the disease and provide a better opportunity to plan for the future.


Ronald Petersen, M.D.

Aug. 05, 2014