All factors

Head injury

Even a single traumatic brain injury increases dementia risk by 37%. Risk rises with each additional injury.

Population risk1.0%
Evidence gradecohort

Why it matters

Head injuries cause inflammation and protein buildup in the brain. Preventing falls and using helmets reduces future risk.

What to ask at the checkup

Ask whether a neurological evaluation is warranted given the head injury history

Screening: History of head injury with loss of consciousness or confusion

Sources

Dementia prevention, intervention, and care: 2024 report of the Lancet Commission

Livingston G, Huntley J, Liu KY et al.. The Lancet, 2024.

Fourteen things people can change account for nearly half of dementia cases at the population level.

Traumatic brain injury and risk of dementia in older veterans

Fann JR, Ribe AR, Pedersen HS et al.. The Lancet Psychiatry, 2018.

Even one head injury raised dementia risk by about a third, and the risk grew with each additional injury.

DOIAbstract only

Routines for this factor

Check the house for fall hazards

Walk through the main rooms and note any loose rugs, dark hallways, or cluttered walkways.

10 min, difficulty 1/3

Put a night light in the hallway

Plug in a night light between the bedroom and the bathroom.

2 min, difficulty 1/3