New Diagnostic Criteria for Alzheimer's Disease
New Diagnostic Criteria for Alzheimer's Disease
The new criteria propose four possible classifications of dementia caused by AD: (1) probable AD dementia, (2) probable AD dementia with increased level of certainty, (3) possible AD dementia and (4) probable or possible AD dementia with evidence of AD pathophysiological process.
The new criteria suggest a four-step approach to diagnosing dementia due to AD (Table 2). Step 1 determines that dementia is present, step 2 determines that the dementia is due to AD, step 3 provides an increased level of certainty to the diagnosis and step 4 evaluates the biomarker probability of AD aetiology. The authors do not advocate obtaining biomarkers for routine clinical purposes at present, although they note that they may be used when available and deemed appropriate by the clinician.
Biomarkers enable the diagnosis of 'probable AD dementia with evidence of the AD pathophysiological process' (Table 1). If one of the two biomarker categories is positive, the 'biomarker probability of AD aetiology' rises to 'intermediate,' and if both categories are positive the probability becomes 'high'.
'Possible AD' is used instead of 'probable AD' if the cognitive deficits look like AD but there is an atypical course (either sudden onset or no definite decline) or evidence of a mixed aetiology. Thus, the patient might meet the criteria for probable AD dementia but there is also evidence of significant vascular disease, features of dementia with Lewy bodies or other disease, or condition that could be contributing to the patient's dementia (Table 3).
The next category is pathophysiologically proven AD, consisting simply of the unchanged criteria of patients meeting both the clinical and neuropathological criteria for AD. Finally, the authors discuss the criteria for dementia unlikely to be due to AD (Table 4).
Criteria for All Cause Dementia and AD
The new criteria propose four possible classifications of dementia caused by AD: (1) probable AD dementia, (2) probable AD dementia with increased level of certainty, (3) possible AD dementia and (4) probable or possible AD dementia with evidence of AD pathophysiological process.
The new criteria suggest a four-step approach to diagnosing dementia due to AD (Table 2). Step 1 determines that dementia is present, step 2 determines that the dementia is due to AD, step 3 provides an increased level of certainty to the diagnosis and step 4 evaluates the biomarker probability of AD aetiology. The authors do not advocate obtaining biomarkers for routine clinical purposes at present, although they note that they may be used when available and deemed appropriate by the clinician.
Biomarkers enable the diagnosis of 'probable AD dementia with evidence of the AD pathophysiological process' (Table 1). If one of the two biomarker categories is positive, the 'biomarker probability of AD aetiology' rises to 'intermediate,' and if both categories are positive the probability becomes 'high'.
'Possible AD' is used instead of 'probable AD' if the cognitive deficits look like AD but there is an atypical course (either sudden onset or no definite decline) or evidence of a mixed aetiology. Thus, the patient might meet the criteria for probable AD dementia but there is also evidence of significant vascular disease, features of dementia with Lewy bodies or other disease, or condition that could be contributing to the patient's dementia (Table 3).
The next category is pathophysiologically proven AD, consisting simply of the unchanged criteria of patients meeting both the clinical and neuropathological criteria for AD. Finally, the authors discuss the criteria for dementia unlikely to be due to AD (Table 4).
Source...