Pathophysiological changes due to AD may occur many years before symptoms appear. The MCI stage provides a potential window to detect and diagnose Alzheimer’s disease before significant neurodegeneration has begun.1-3
Yet, AD remains underdiagnosed and underreported. In fact, the average diagnosis is delayed by an average of 2 to 3 years after symptom onset.2,4
AD is the most common cause of MCI,* accounting for an estimated 34% to 75% of all patients.6,7 Patients with suspected MCI should undergo a comprehensive history and physical examination to distinguish MCI from normal aging or dementia, and separate it from other causes.8 Alzheimer’s disease biomarkers may provide evidence of the underlying cause.9
*In the Aging, Demographics, and Memory Study (ADAMS), individuals were classified as having cognitive impairment without dementia.6
Read these patient profiles to see how cognitive tests can strengthen assessments and biomarker testing can confirm the diagnosis of different patient types.
Family history of AD/dementia: No
Patient reports: Missed appointments
Informant reports: Noticeable memory loss, repeats himself
Psychiatric symptoms: None
Blood cell count, electrolytes, glucose, calcium, thyroid function, vitamin B12, folate: Within Normal Range
Hypertension (controlled)
Normal with some mild bilateral upper-extremity action tremor
MCI-sensitive test conducted, MoCA=25/30; Wechsler Memory Scale-Logical Memory (WMS-LM): 100% immediate recall, 69% delayed recall
Informant report: Fully independent (3/30 on FAQ)
Hippocampal atrophy, periventricular white matter hyperintensities
Amyloid positive
Family history of AD/dementia: No
Patient reports: Increased memory loss, visuospatial issues
Informant reports: Loss of balance, needs to be accompanied
Psychiatric symptoms: Mild anxiety
Blood cell count, electrolytes, glucose, calcium, thyroid function, vitamin B12, folate: Within Normal Range
Coronary artery disease and diabetes (controlled)
Difficulty with ideomotor praxis testing, like combing her hair, and some diminished balance
MMSE®=24/30
Informant report: Increased dependence (13/30 on FAQ). Dependent for financial matters; traveling out of neighborhood
Ventricular dilation, mild frontal and anterior temporal atrophy temporal atrophy
Amyloid- and tau-positive
MMSE is a registered trademark of Psychological Assessment Resources.
FAQ=Functional Activities Questionnaire; MMSE=Mini Mental State Examination.
Learn more with these practical examples of
early-stage Alzheimer’s disease diagnosis
containing additional information.