[Alzheimer's disease and other neurocognitive disorders - epidemiology and new diagnostic criteria].

Neurocognitive disorders are progressive conditions leading to brain atrophy and functional decline, representing the third leading cause of death in Sweden after cardiovascular disease and cancer. Approximately 150 000 individuals live with a dementia diagnosis, with Alzheimer's disease (AD) comprising two-thirds of cases, followed by vascular cognitive impairment. Diagnosis is usually initiated in primary care through patient history, cognitive testing, laboratory analyses, and brain imaging, while more advanced assessments in specialist clinics may include cerebrospinal fluid or blood biomarkers. Traditionally, diagnoses in Sweden have relied on ICD-10, emphasizing cognitive decline affecting daily life. Recently, biomarker-based frameworks such as NIA-AA and IWG have redefined AD either as a purely biological entity (NIA-AA) or as a clinico-biological construct (IWG). While these are primarily used in research, they highlight the importance of integrating biological markers with clinical evaluation. Preventive strategies remain crucial, as pathological processes can precede symptoms by decades.