Snapshot A 76-year-old man is brought to the clinic by his son, who has been concerned about his father's mental decline in the past few years. He says that his father moved in with him 3 years ago because he was having trouble paying his bills and maintaining his house alone. In the past year, his father has begun to have trouble dressing himself without assistance and has had multiple episodes of wandering around the neighborhood and being unable to find his way back to his son's home. Upon questioning, the patient is able to state his first and last name and is aware that he is in the hospital but struggles to remember the date. When asked to remember 3 simple items, he is unable to recall all but 1 of them after 5 minutes. He is pleasant and alert but remains mostly quiet and repeats himself when asked more detailed questions about his day. Introduction Overview major neurocognitive disorder (formerly called dementia under the DSM-IV) is characterized by impairments in memory, speech, comprehension and reasoning, and spatial-temporal awareness Epidemiology prevalence 12-20% of individuals ≥ 65 years of age in the US demographics most common in individuals ≥ 60 years of age more common in African-Americans than Caucasians Pathophysiology causative etiologies include: neurodegenerative brain diseases Alzheimer disease > 50% of cases of major neurocognitive disorder Parkinson disease frontotemporal dementia dementia with Lewy bodies Huntington disease cerebrovascular disease ~20% of cases of major neurocognitive disorder hypoxic brain damage Wilson disease syphilis progressive multifocal leukoencephalopathy HIV Creutzfeldt-Jakob disease Prognosis memory impairment progressively worsens patients may require assistance with activities of daily living (ADLs), such as dressing, bathing, and using the bathroom feeding difficulties may require placement of a permanent gastrointestinal tube time from diagnosis to death may vary from 3-10+ years Presentation Symptoms memory loss gradual, progressive cognitive impairment aphasia apraxia agnosia loss of abstract thought impaired judgment behavioral/personality changes no change in level of consciousness Physical exam Mini-Mental State Examination (MMSE) 20–24 points mild level of major neurocognitive disorder 13–20 points moderate level of major neurocognitive disorder < 13 points advanced level ofmajor neurocognitive disorder Montreal Cognitive Assessment (MoCA) 18–25 points mild cognitive impairment 10–17 points moderate cognitive impairment < 10 points severe cognitive impairment Imaging Noncontrast head CT or MRI detect reversible causes of dementia (e.g., tumor and hematoma) Studies Laboratory studies vitamin B12 thyroid hormone levels Differential Normal aging key distinguishing factor independence in daily activities is preserved Major depressive disorder key distinguishing factor cognitive deficits manifest after mood symptoms cognition improves after effective antidepressant therapy Treatment Lifestyle cognitive stimulation techniques image recognition practice arithmetic practice Medical cholinesterase inhibitors (e.g., donepezil, rivastigmine, and galantamine) first-line treatment for Alzheimer disease and vascular dementia memantine moderate to advanced cases of Alzheimer disease and vascular dementia