Multifactorial Causation
Unlike infectious diseases, which often follow the “Epidemiological Triad” (single-agent focus), chronic diseases typically arise from a complex interplay of numerous risk factors. This is known as Multifactorial Causation (or the Web of Causation).
Key Models
| Model | Focus |
|---|---|
| Web of Causation | Visualizes disease as the result of a complex network of interrelated factors (genetic, environmental, behavioral). |
| Rothman’s Causal Pies | Suggests diseases are caused by a “sufficient cause” made up of several “component causes” (the slices of the pie). |
High-Yield Clinical Notes:
- Sufficient vs. Necessary:
- Sufficient Cause: A complete constellation of factors that *inevitably* produces disease.
- Component Cause: An individual factor that contributes to the disease process.
- Necessary Cause: A component cause that *must* be present for disease to occur (e.g., Mycobacterium tuberculosis for TB).
- Application: This model is essential for understanding NCDs (Non-Communicable Diseases) like hypertension, diabetes, and cancer, where there is no “single” cause, but rather an accumulation of risk.