I've read that researchers have changed the definition of Alzheimer's disease dementia. What does that mean for me and my loved one affected by the disease?

Answer From Jonathan Graff-Radford, M.D.

The National Institute on Aging and the Alzheimer's Association have made changes to the research definition of Alzheimer's disease dementia. The changes include criteria to define what Alzheimer's disease dementia is and who has it. But the changes apply only to clinical trials and research. The changes don't affect how a person is diagnosed in a health care provider's office.

Previously, Alzheimer's disease dementia was diagnosed based on symptoms such as memory loss and changes in thinking and cognition. And that's still the case when a provider makes a diagnosis.

The research definition calls for a biological definition of Alzheimer's disease dementia that can be made during life. It's determined by detecting the presence of biomarkers — a buildup of plaques and tangles in the brain. Biomarkers can be seen on imaging scans of the brain. They also can be identified in samples of cerebrospinal fluid and in the fluid part of blood.

This definition change allows researchers to better design clinical trials and include the right people to be part of the trials. As a result, researchers learn more about the disease in its earlier stages.

Here's why it's important: The classic symptoms that are used to diagnose Alzheimer's disease dementia are a complication of the changes in the brain that define the disease. These brain changes can occur long before symptoms show up. Changing the research definition may lead to earlier diagnosis, which will hopefully lead to delayed disease progression and better treatments.


Jonathan Graff-Radford, M.D.

Nov. 04, 2022 See more Expert Answers

See also

  1. Alzheimer's sleep problems
  2. Alzheimer's: New treatments
  3. Alzheimer's 101
  4. Alzheimer's and daily tasks
  5. Understanding the difference between dementia types
  6. Alzheimer's disease
  7. Alzheimer's drugs
  8. Alzheimer's genes
  9. Alzheimer's nose spray: New Alzheimer's treatment?
  10. Alzheimer's prevention: Does it exist?
  11. Alzheimer's stages
  12. Antidepressant withdrawal: Is there such a thing?
  13. Antidepressants and alcohol: What's the concern?
  14. Antidepressants and weight gain: What causes it?
  15. Antidepressants: Can they stop working?
  16. Antidepressants: Side effects
  17. Antidepressants: Selecting one that's right for you
  18. Antidepressants: Which cause the fewest sexual side effects?
  19. Anxiety disorders
  20. Atypical antidepressants
  21. Caregiver stress
  22. Clinical depression: What does that mean?
  23. Corticobasal degeneration (corticobasal syndrome)
  24. CT scan
  25. Depression and anxiety: Can I have both?
  26. Depression, anxiety and exercise
  27. What is depression? A Mayo Clinic expert explains.
  28. Depression: Diagnosis is key
  29. Depression in women: Understanding the gender gap
  30. Depression (major depressive disorder)
  31. Depression: Provide support, encouragement
  32. Depression: Supporting a family member or friend
  33. Diagnosing Alzheimer's
  34. Intermittent fasting
  35. Lecanemab for Alzheimer's disease
  36. Male depression: Understanding the issues
  37. MAOIs and diet: Is it necessary to restrict tyramine?
  38. Marijuana and depression
  39. Mayo Clinic Minute: 3 tips to reduce your risk of Alzheimer's disease
  40. Mayo Clinic Minute: Alzheimer's disease risk and lifestyle
  41. Mayo Clinic Minute New definition of Alzheimer's changes
  42. Mayo Clinic Minute: Women and Alzheimer's Disease
  43. Memory loss: When to seek help
  44. Monoamine oxidase inhibitors (MAOIs)
  45. MRI
  46. Natural remedies for depression: Are they effective?
  47. Nervous breakdown: What does it mean?
  48. New Alzheimers Research
  49. Pain and depression: Is there a link?
  50. Phantosmia: What causes olfactory hallucinations?
  51. Positron emission tomography scan
  52. Posterior cortical atrophy
  53. Seeing inside the heart with MRI
  54. Selective serotonin reuptake inhibitors (SSRIs)
  55. Serotonin and norepinephrine reuptake inhibitors (SNRIs)
  56. Brain anatomy
  57. Sundowning: Late-day confusion
  58. Treatment-resistant depression
  59. Tricyclic antidepressants and tetracyclic antidepressants
  60. Video: Alzheimer's drug shows early promise
  61. MRI
  62. Vitamin B-12 and depression
  63. Young-onset Alzheimer's