Cognitive Decline

A daughter reports that her 78-year-old father repeats the same questions, has missed two bill payments, and became lost driving to a familiar store. The first clinical question is not which dementia medication to prescribe. It is whether there is a true decline, whether function has been affected, whether delirium or another reversible contributor is present, and which disease process best explains the pattern. The primary care evaluation therefore has three linked targets: functional status, the cognitive-behavioral syndrome, and the likely underlying cause or causes [5]. Cognitive impairment becomes dementia when the decline interferes with usual activities and is not better explained by delirium or a major psychiatric disorder [26]. Mild cognitive impairment describes objective decline with relative preservation of independence; a person may need more time, reminders, or compensatory strategies without losing the ability to manage usual activities. Alzheimer disease is no longer defined only by a clinical memory syndrome. The 2024 revised criteria define it biologically by Alzheimer disease neuropathologic change—beta-amyloid plaques together with tau neurofibrillary tangles. Core 1 biomarkers change early and include amyloid PET, approved cerebrospinal...