Geriatric prognosis

Life Expectancy in Alzheimer’s Disease

Disease progression and survival in Alzheimer’s vary widely. This tool provides an educational estimate using published averages for stage, adjusted by patient factors. It should not replace clinical judgement or individualized prognostication.

Include heart failure, COPD, CKD, diabetes with complications, etc.

Estimated life expectancy

4.2 years

Intermediate expectancy

Discuss progression, safety planning, and community resources with caregivers.

Values based on pooled observational studies; adjust for patient-specific trajectories.

How to Use This Calculator

1

Assess Alzheimer’s stage

Classify as mild, moderate, or severe using MMSE, FAST scale, or clinical evaluation.

2

List major comorbidities

Count conditions significantly impacting survival (cardiovascular, pulmonary, renal, malignancy type).

3

Discuss results with caregivers

Use the estimate for care planning, not as a precise prognosis. Emphasize ongoing reassessment.

Formula

Base expectancy derived from stage-specific mean survival:

  • Mild: ~7 years (male), ~8.5 years (female)
  • Moderate: ~4.5 years (male), ~5.5 years (female)
  • Severe: ~2.5 years (male), ~3.0 years (female)

Adjusted expectancy = Base × Age factor + Comorbidity adjustment + Functional status adjustment

Age factor ≈ 1.2 (<75), 1.0 (75–84), 0.8 (85–89), 0.6 (≥90). Comorbidity adjustment: −0.8 for 3–5, −1.5 for >5.

Full Description

Survival in Alzheimer’s disease depends on age, sex, disease severity, comorbidity burden, and functional status. Mild disease may progress over many years, while severe stages often correlate with reduced mobility, swallowing difficulties, and higher infection risk. Estimates assist caregivers in planning resources, legal affairs, and transitions in care.

This tool aggregates data from cohort studies. It does not account for specific genetic markers, response to therapy, or acute events (e.g., aspiration pneumonia). Reassess prognosis periodically and tailor discussions to patient goals and caregiver needs.

Frequently Asked Questions

Is this model validated for all demographics?

No. Data largely comes from North American and European cohorts. Cultural, socioeconomic, and healthcare differences may affect survival.

Can treatments extend life expectancy?

Symptomatic treatments may slow cognitive decline but do not significantly alter overall survival. Manage comorbidities aggressively for best outcomes.

How often should we revisit prognosis?

At least annually or with major status changes (new comorbidity, functional decline, hospitalization).

Does hospice eligibility align with severe stage?

Hospice criteria include FAST stage ≥7C and complications (pneumonia, aspiration, weight loss). Use this estimate alongside formal criteria.