Cognitive Decline (Non-Dementia)

What it is

A spectrum from age-related cognitive decline (subtle slowing, word-finding hiccups starting in the 50s–60s) through subjective cognitive decline (SCD), mild cognitive impairment (MCI), and dementia. Decline in episodic memory and processing speed is most age-sensitive.

Why act early

• Decades of pre-clinical disease precede dementia diagnosis.
• Interventions are more impactful before significant neuronal loss.
• Many causes are reversible (sleep apnoea, depression, thyroid disease, B12 deficiency, certain medications).

The Lancet Commission’s 14 modifiable risk factors

The 2024 Lancet Commission update implicates 14 modifiable factors that together may explain ~45% of dementia risk. Major ones:

• Low education (early life).
• Hearing loss (untreated).
• Hypertension.
• Smoking.
• Obesity.
• Depression.
• Physical inactivity.
• Diabetes.
• Excessive alcohol.
• Air pollution.
• Social isolation.
• Traumatic brain injury.
• Vision loss (untreated).
• Cholesterol (LDL).

The FINGER framework

The FINGER trial (Finland, 2015) tested a multidomain intervention — nutrition, exercise, cognitive training, cardiovascular risk monitoring — and slowed cognitive decline in at-risk older adults. Follow-on world-wide FINGER initiatives test the same framework across populations.

High-leverage personal actions

• Get hearing tested and use aids if needed.
• Control blood pressure, lipids, glucose.
• Train (zone 2 + resistance + balance).
• Maintain strong social ties.
• Protect sleep; treat OSA.
• Cognitive engagement (learning, complex tasks).

Related entries

Alzheimer's disease, FINGER trial, Sleep optimization, Exercise.