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Why Early Matters

By the time Alzheimer’s disease symptoms appear, the pathology of amyloid and tau may have been present for decades, making diagnosis a priority1,2

Once symptoms present, time is of the essence2,3

Timely assessment can make a difference for your patients with cognitive impairment and can lead to2,4:

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Prompt evaluation and treatment of reversible causes

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Access to clinical trials

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Opportunity to consider available therapies

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More active involvement in medical care and decision-making

Alzheimer’s disease can be difficult to diagnose, especially earlier in the disease when symptoms are subtle2

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Diagnosis is delayed on average by 2-3 years after symptom onset—and often made only in the latter stages of the disease. To intervene early, the cause of cognitive impairment should be identified as soon as symptoms occur.5-8

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Over 50% of patients with dementia have never been formally diagnosed—but 89% (N=639) of people surveyed from the US said that they would want to know if Alzheimer’s disease (AD) is the cause of their cognitive impairment.9-11

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Nearly 1 in 3 people clinically diagnosed with AD had no evidence of amyloid plaques*; however, there is evidence that the biomarkers of AD pathophysiology can help assess for AD.12-14

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*In a large study using amyloid PET scans.
PET=positron emission tomography.


  1. McDade E, Bednar M, Brashear HR, et al. The pathway to secondary prevention of Alzheimer's disease. Alzheimers Dement (N Y). 2020;6(1):1-9.
  2. Aisen PS, Cummings J, Jack CR, et al. On the path to 2025: understanding the Alzheimer's disease continuum. Alzheimers Res Ther. 2017;9(1):60.
  3. Ty D, McDermott M. Building workforce capacity to improve detection and diagnosis of dementia. Milken Institute; 2021. Accessed August 12, 2021.
  4. Hort J, O'Brien JT, Gainotti G, et al. EFNS guidelines for the diagnosis and management of Alzheimer's disease. Eur J Neurol. 2010;17(10):1236-1248.
  5. Sabbagh MN, Lue LL, Fayard D, Shi J. Increasing precision of clinical diagnosis of Alzheimer’s disease using a combined algorithm incorporating clinical and novel biomarker data. Neurol Ther. 2017;6(1):S83-S95.
  6. Boise L, Morgan DL, Kaye J, et al. Delays in the diagnosis of dementia: perspectives of family caregivers. Am J Alzheimers Dis Other Dement. 1999;14:20-26.
  7. Balasa M, Gelpi E, Antonell A, et al. Clinical features and APOE genotype of pathologically proven early-onset Alzheimer disease. Neurology. 2011;76(20):1720-1725.
  8. Porsteinsson AP, Isaacson RS, Knox S, Sabbagh MN, Rubino I. Diagnosis of early Alzheimer’s disease: clinical practice in 2021. J Prev Alzheimers Dis. 2021;3(8):371-386.
  9. Lang K, Clifford A, Wei L, et al. Prevalence and determinants of undetected dementia in the community: a systematic literature review and a meta-analysis. BMJ Open. 2017;7(2):e011146.
  10. Boustani M, Peterson B, Hanson L, et al; U.S. Preventive Services Task Force. Screening for dementia in primary care: a summary of the evidence for the U.S. Preventive Services Task Force. Ann Intern Med. 2003;138(11):927-937.
  11. Blendon RJ, Benson JM, Wikler EM, et al. The impact of experience with a family member with Alzheimer's disease on views about the disease across five countries. Int J Alzheimers Dis. 2012;2012:903645.
  12. Rabinovici GD, Gatsonis C, Apgar C, et al. Association of amyloid positron emission tomography with subsequent change in clinical management among Medicare beneficiaries with mild cognitive impairment or dementia. JAMA. 2019;321(13):1286-1294.
  13. Grundman M, Pontecorvo MJ, Salloway SP, et al. Potential impact of amyloid imaging on diagnosis and intended management in patients with progressive cognitive decline. Alzheimer Dis Assoc Disord. 2013;27(1):4-15.
  14. Jack CR, Bennett DA, Blennow K, et al. NIA-AA Research Framework: toward a biological definition in Alzheimer's disease. Alzheimers Dement. 2018;14(4):535-562.