All factors

Vision loss

Uncorrected vision impairment was linked to a 78% higher dementia rate in a UK cohort of 117,000 older adults.

Population risk2.0%
Evidence gradeCohort study

A large group of people followed for years or decades. Shows a real-world link, though not proof of cause by itself.

Why it matters

Poor vision limits reading, social engagement and physical activity, each of which protects the brain independently.

What to ask at the checkup

Ask whether a full eye exam is due and whether the current prescription is still correct

Screening: Visual acuity test (Snellen chart)

Sources

Visual Impairment and Risk of Dementia: The UK Biobank Study

Zhu Z, Shi D, Liao H et al.. American Journal of Ophthalmology, 2022.

People with poor vision that glasses did not fully correct had close to twice the dementia risk over six years.

DOIAbstract only

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

Routines for this factor

Book the eye exam

Call or go online and book a full eye exam.

5 min, difficulty 1/3

This is research information, not medical advice. Nothing here replaces your parent's doctor.