BAYESIAN CAUSAL DEMENTIA RISK — Pearl SCM v4

Age & Sex-Adjusted · Idiosyncratic Floor Always Present · 23 Risk Factors · 16 Interventions · Pareto Analysis · build v3.20
Baseline
Irreducible
Your Risk
After Interv.
Mod. PAF
Min E-Val
Overview
Pareto Analysis
Do-Calculus
Counterfactual
Sensitivity
Causal DAG
Viral Hypothesis
Supplements
Mechanisms
👤 Demographics
Age 70
Sex
10-yr baseline risk
Irreducible floor
Modifiable burden
After interventions
Irreducible
Modifiable
Protected
Controls
Risk (23)
Interventions (16)
A=Strong (RCT/large) · B=Moderate/observational · C=weaker · D=consensus. Lower grades excluded from the combined PAF.
Risk Decomposition (10-year cumulative probability) — Idiosyncratic floor is always > 0
Age/Sex Baseline
(population avg)
Irreducible Floor
(non-modifiable)
Your Risk
(active factors)
After Interventions
(theoretical min)
Irreducible floor = Baseline × (1 − PAF_max = 0.527). Even with zero modifiable risk factors, this floor is never zero.
Baseline (Age/Sex)
Irreducible Floor
Baseline × 0.473; always > 0
Your Risk
After Interventions
Applying active protective interventions
Modifiable PAF
Fraction attributable to active risk factors
Protection RR
Combined HR of active interventions
Cases Prevented / 1,000
At your age/sex baseline
Active Risk / Interv.
of 23 risk / 16 interventions
Risk Decomposition — Stacked Components
Age-Sex Baseline Dementia Risk Curves
PAF by Active Risk Factor (sorted)
Hazard Ratio — All 23 Factors
Target Risk Reduction: 70% = reduce personal risk from to
Sort order: Set all adherence:
✓ Minimum Viable Protocol
Cumulative Risk Reduction (Pareto Order)
Individual Contribution by Intervention (Adherence-Adjusted)
Baseline is ALWAYS age-sex-adjusted (never zero): Irreducible = Baseline(age,sex) × (1 − PAF_max) [PAF_max = 0.527 for all 23 factors] Personal = Irreducible + Baseline × PAF_selected do(X_i=0) = Personal − Baseline × PAF_i [Pearl interventional distribution]
Risk Factors
Risk FactorStageHRPrevPAF Abs. BurdenPrevented/1kdo(X=0) RiskE-Value
Protective Interventions
InterventionCategoryHRAbs. RR (your baseline)Saved/1kEvidence
PN = P(Y_{x=0}=0 | X=1, Y=1) — lower bound under monotonicity: PN ≥ (HR − 1) / HR PS uses YOUR age-sex baseline (not a generic 10%): PS ≈ Baseline(age,sex) × (HR − 1)
FactorHRPN (If-Not-For)PS (Sufficient)PNSMR RRRC RiskHR−MR Gap
PN (Probability of Necessity) by Factor
Observational HR vs Mendelian RR
E-Value (VanderWeele & Ding 2017) — minimum unmeasured confounding to nullify HR: E-value = HR + √(HR × (HR − 1)) Both the confounder–exposure AND confounder–outcome association must be ≥ E-value simultaneously.
FactorStageHR95% CIE-Val (HR)E-Val (CI lower)RobustnessRC Risk
Causal DAG — Age & Sex as Root Nodes Green=Early · Yellow=Mid · Orange=Late · Pink=Viral · Purple=Genetic/Root
DAG: Age and Sex are root nodes (purple) that directly modify baseline risk AND modulate multiple pathways (e.g., age → hearing loss, age → depression; sex → depression, sex → longevity). Pink = viral/infectious. Solid arrows = direct causal. Dashed = mediated. APOE ε4 amplifies herpes ×4.64 and impairs Aβ clearance.
🦠 Viral Hypothesis (Berkowitz/Moir/Itzhaki): Aβ is an innate immune antimicrobial peptide that envelops neurotropic herpesviruses. Aging immune senescence → clearance failure → microglial activation → tau → neuronal death. Acyclovir 90d (Taiwan N=34M): HR 0.092; E-value 10.24 — strongest single protective signal in dementia prevention.
Antiviral HR by Drug & Duration (Taiwan NHIRD)
Acyclovir Dose-Response: Days vs Risk Reduction
Neurotropic Pathogens
PathogenPrevalenceHRE-ValueCNS EntryInterventionEvidence
💊 Berkowitz Protocol — Zero Downside Risk Threshold. "Yokul-ten, dvun-weht, dif-tor heh smusma" — Eat less, move more, live long and prosper. All items pass zero-downside-risk screening.
Berkowitz Protocol — Causal Analysis
Supplement / InterventionDoseHR / EffectMechanismEvidenceNotes
Mechanisms of Action — All 23 Risk Factors
FactorStagePrimary MechanismNeuropathologyInterventionEvidence