15.7 : アルツハイマー病：概要

Alzheimer's disease, or AD, is a neurodegenerative disorder primarily affecting older adults, causing impaired memory and cognitive decline through three stages: preclinical, mild cognitive impairment, and dementia.

Its pathophysiology involves Aβ amyloid plaques and tau protein neurofibrillary tangles, resulting in cholinergic neuron loss.

Neurochemically, AD exhibits reduced neurotransmitter levels of acetylcholine, serotonin, and norepinephrine.

Its clinical diagnosis includes medical evaluation, brain imaging, neuropsychological assessment, and cerebrospinal fluid analysis.

Specific biomarkers like Aβ and tau protein changes in cerebrospinal fluid, and hippocampal atrophy, and cortical hypometabolism in imaging,  confirms AD.

Certain gene mutations, such as APP, PSEN1, and PSEN2, can trigger early-onset AD with autosomal dominance.

Biochemical changes in AD include inflammation, oxidative stress, and mitochondrial dysfunction.

Current treatments prioritize symptom relief and disease progression deceleration. For instance, cholinesterase inhibitors are used to manage behavioral symptoms.