Alzheimer’s disease (AD) is a progressive and incurable neurodegenerative disease with a long preclinical period that is characterized by cognitive and behavioral impairment that greatly interferes with social and occupational functioning.
Prevalence of AD increases with age, with most cases occurring in individuals ≥ 60 years. There appears to be a higher prevalence in females than in males. In the United States, AD and other dementias are twice as common in Black individuals when compared with the prevalence in White individuals.
AD is a clinical diagnosis, primarily using patient history, presenting symptoms and results from a Mental Status Examination. The diagnosis is usually made during the mild stage of the disease. Imaging studies and laboratory testing are ancillary tools that may be used to help rule out organic causes of symptoms. In 2022, the Food and Drug Administration approved a blood test that measures the Alzheimer’s biomarker, plasma phosphorylated tau (p-tau). A device that is used for this blood test was introduced to consumers in 2023 and allows individuals to have their p-tau measured at a lab. However, at this time, an autopsy or brain biopsy is the only way to make a definitive diagnosis of AD.
Symptomatic therapies (cholinesterase inhibitors and N-methyl-D-aspartate) are currently the mainstay of treatment for AD but do not address the causes of disease, nor halt their progression. As of 2023, two anti-amyloid beta (Aβ) monoclonal antibodies, aducanumab, and lecanemab, were made available for the treatment of AD and work by reducing amyloid plaques in the brain. They might be the first disease-modifying agents in AD. Additional medications are used to treat secondary symptoms of AD (eg, depression and sleep disorders). Investigations continue to elucidate the continuum between the development of AD and normal aging.
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