Erfan Bashar
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Alzheimer Disease

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Educational scope notice: This is a study note for medical students, not medical advice, diagnosis, or treatment guidance. Clinical management should follow local protocols and current guidelines.

Alzheimer disease is the most common cause of dementia. It begins insidiously, usually in later life, with a gradual failure to form new memories, and progresses over years to affect language, spatial reasoning, judgment, and eventually basic self-care. There are no early motor signs and no focal neurological deficits. The disease is cortical and degenerative from the start.

Choose a route through the topic

  • Alzheimer Disease Pathophysiology: how amyloid, tau, vessel injury, selective atrophy, and transmitter loss produce the memory-first course, and which factors raise risk.
  • Alzheimer Disease Clinical Presentation: the order in which cognitive domains fail, the behavioural changes that accompany decline, where mild cognitive impairment ends and dementia begins, and how the bedside pattern differs from other dementias.
  • Alzheimer Disease Diagnosis: what must be shown before calling it dementia, how bedside scores and biomarkers each contribute, and the order in which to use them.
  • Alzheimer Disease Treatment: what current drugs can and cannot do, how non-drug care carries the day-to-day weight, and which drugs cause harm.

The useful sequence is mechanisms first, then the clinical picture, then diagnosis, then treatment. The pathology explains both why memory fails first and why each drug does only what it does.

Epidemiology

Risk rises steeply with age, and women are affected more often than men, partly because they live longer on average. Most cases are sporadic and late-onset; a small minority are familial with early onset. Reported prevalence figures vary across populations because case ascertainment and methodology differ.

Evidence anchors

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