Alzheimer disease (AD) is a chronic, progressive neurodegenerative disorder characterized by a global, nonreversible impairment in cerebral functioning.
AD is characterized by memory loss, loss of social and occupational functioning, diminished executive function, speech and motor deficits, personality change, and behavioral and psychological disturbance.
It has a deteriorating course over up to 8-10 years.
Brain lesions are marked by neurofibrillary tangles, senile plaques, neuronal loss, and brain atrophy, with defects in acetylcholine synthesis at the cellular level.
Treatment requires a multidisciplinary approach with increasing emphasis on behavioral and psychological symptoms.
Psychosocial interventions and caregiver support are key to managing disease course. Caregiver support groups are beneficial to caregivers and should be considered, where available.
Alzheimer disease (AD) is a chronic neurodegenerative disease with an insidious onset and progressive but slow decline. AD is the most common type of dementia. It often coexists with other forms of dementia, particularly vascular dementia (mixed-type dementia). The histopathology of AD is characterized by senile plaques, neurofibrillary tangles, and neuronal loss. The hallmark symptoms are memory loss, impairment of daily activities, and neurobehavioral abnormalities. Definition of severity varies according to country, but a commonly accepted categorization is mild, moderate, and severe. The Mini-Mental State Examination can be used as a guide to cognitive impairment, but education, language, and any other relevant factors must be taken into consideration when interpreting scores.
History and exam
Key diagnostic factors
- memory loss
- nominal dysphasia
- misplacing items/getting lost
- decline in activities of daily living and instrumental activities of daily living (IADLs)
- personality change
- unremarkable initial physical exam
Other diagnostic factors
- mood changes
- poor abstract thinking
- constructional dyspraxia
- advanced age
- family history
- Down syndrome
- cerebrovascular disease
- lifestyle factors and medications
- less than high school education
- traumatic brain injury
- hearing loss
- female sex
- elevated plasma homocysteine level
- artificially sweetened soft drink consumption
1st investigations to order
- bedside cognitive testing
- metabolic panel
- serum thyroid-stimulating hormone (TSH)
- serum vitamin B12
- urine drug screen
Investigations to consider
- cerebrospinal fluid (CSF) analysis
- serum rapid plasma reagin/Venereal Disease Research Laboratory (VDRL)
- serum HIV
- formal neuropsychological testing
- genetic testing
- fluorodeoxyglucose-PET (FDG-PET)
- single-photon emission CT (SPECT)
- electroencephalogram (EEG)
Judith Neugroschl, MD
Associate Professor of Psychiatry
Icahn School of Medicine at Mount Sinai
JN declares that she has no competing interests.
Dr Judith Neugroschl would like to gratefully acknowledge Dr Brandy R. Matthews, Dr Asif S. Bhutto, and Dr Julie K. Gammack, the previous contributors to this topic.
BRM, ASB, and JKG declare that they have no competing interests.
Roy J. Goldberg, MD, FACP, AGSF, CMD
Kings Harbor Multicare Center
RJG declares that he has no competing interests.
Philip Scheltens, MD, PhD
Professor of Neurology
Department of Neurology/Alzheimer Center
VU University Medical Center
PS declares that he has no competing interests.
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