Alzheimer's and dementia distinction explained by neurobiology

Neurobiologist Seyedeh Zahra Motavalian has provided insights into the distinction between dementia and Alzheimer's disease, noting that the biological processes leading to cognitive decline often begin between the ages of 30 and 40. While symptoms like memory loss typically manifest in the 60s or 70s, lifestyle and environmental factors play a critical role in brain susceptibility over several decades.

Dementia is described as a syndrome involving the progressive decline of cognitive functions, including memory, language, and decision-making. Alzheimer's accounts for 60% to 70% of dementia cases, followed by vascular dementia, which results from small strokes and constitutes 10% to 20% of cases.

Regarding genetics, Motavalian clarified that less than 5% of Alzheimer's cases are caused by dominant hereditary mutations. In over 95% of individuals, the disease is sporadic, meaning that while genes may increase predisposition, lifestyle choices determine whether the disease develops. Key preventative measures include managing hypertension, diabetes, chronic stress, and unhealthy diets, alongside regular physical activity.