A 76-year-old woman is brought to a primary care physician by her daughter who is concerned about her mother's growing inability to take care of herself. Initially, she attributed her mother's forgetfulness and word-finding difficulties to normal aging, but over the past few years, her mother's memory has worsened, her mood has grown more irritable, and her mother has been found wandering the neighborhood unsure of how to get home. Her medical history includes type 2 diabetes mellitus which is well-controlled with metformin. On exam, her temperature is 98.2°F (36.8°C), blood pressure is 115/82 mmHg, pulse is 73/min, respirations are 12/min, and oxygen saturation is 99% on room air. Cardiopulmonary exam reveals normal S1 and S2, no murmurs, and clear lungs bilaterally. She scores 16/30 on the Montreal Cognitive Assessment (MoCA) test. Which of the following is the most likely diagnosis?
Normal pressure hydrocephalus
Frontotemporal dementia
Alzheimer dementia
Creutzfeldt-Jakob disease
Alzheimer dementia
This elderly patient who presents with slowly progressive memory loss, language difficulties, and progression to inability to care for herself most likely has Alzheimer dementia.

Alzheimer dementia is a neurodegenerative disorder that is characterized by a gradual and progressive cognitive decline (memory loss, visuospatial and language deficits, impaired judgment), difficulties with executive function or carrying out activities of daily living, and sometimes psychiatric disturbances and behavioral changes (apathy, irritability, social isolation). It is the most common cause of dementia and its risk factors include increasing age, female gender, family history, and trisomy 21 (due to the amyloid precursor protein found on chromosome 21). This is a clinical diagnosis based on cognitive testing (such as the Montreal Cognitive Assessment or the mini-mental status exam) and ruling out other causes of dementia (vitamin B12 deficiency, depression, or hypothyroidism).

Weller et al. review the current understanding of Alzheimer dementia pathophysiology. They discuss recent advances in clinical evaluation and treatment. They recommend having a high index of suspicion for the disease in elderly patients who appear to be regressing in their ability to take care of themselves.

Incorrect Answers:
Answer B: Creutzfeldt-Jakob disease is a rapidly progressive neurodegenerative disorder caused by a prion protein that is fatal, leading to death usually within 1 year of illness onset. Dementia progresses rapidly in this disease and is sometimes associated with startle myoclonus.

Answer C: Frontotemporal dementia (FTD) is characterized primarily by disinhibition, apathy, or aphasia as a result of atrophy of the frontal and temporal lobes. It tends to occur at a younger age than does Alzheimer dementia. Behavioral changes are often the first noticeable symptom in FTD while they tend to occur later in Alzheimer disease progression. Problems with visuospatial orientation are more common in Alzheimer dementia than in FTD.

Answer D: Normal pressure hydrocephalus (NPH) typically presents with a triad of dementia, gait instability (specifically magnetic gait, marked by an inability to lift feet off the floor), and urinary incontinence. In NPH, excess cerebrospinal fluid accumulates in the brain's ventricles, and treatment involves drainage of that fluid, usually via surgical placement of a shunt.

Answer E: Vascular dementia typically presents as stepwise cognitive decline in the setting of stroke or brain injury and usually occurs in patients with the same risk factors as stroke, such as hypertension, hyperlipidemia, peripheral arterial disease, and smoking. This patient has neither hypertension nor stepwise decline.

Bullet Summary:
Alzheimer dementia presents with slowly progressive dementia, typically manifesting with memory loss, visuospatial and language difficulties, impaired judgment, and inability to care for oneself.