Table 1.
PAF for 12 dementia risk factors
| Relative risk for dementia (95% CI) | Risk factor prevalence | Communality | Unweighted PAF | Weighted PAF* | |
|---|---|---|---|---|---|
| Early life (<45 years) | |||||
| Less education | 1·6 (1·3–2·0) | 40·0% | 61·2% | 19·4% | 7·1% |
| Midlife (age 45–65 years) | |||||
| Hearing loss | 1·9 (1·4–2·7) | 31·7% | 45·6% | 22·2% | 8·2% |
| Traumatic brain injury | 1·8 (1·5–2·2) | 12·1% | 55·2% | 9·2% | 3·4% |
| Hypertension | 1·6 (1·2–2·2) | 8·9% | 68·3% | 5·1% | 1·9% |
| Alcohol (>21 units/week) | 1·2 (1·1–1·3) | 11·8% | 73·3% | 2·1% | 0·8% |
| Obesity (body-mass index ≥30) | 1·6 (1·3–1·9) | 3·4% | 58·5% | 2·0% | 0·7% |
| Later life (age >65 years) | |||||
| Smoking | 1·6 (1·2–2·2) | 27·4% | 62·3% | 14·1% | 5·2% |
| Depression | 1·9 (1·6–2·3) | 13·2% | 69·8% | 10·6% | 3·9% |
| Social isolation | 1·6 (1·3–1·9) | 11·0% | 28·1% | 4·2% | 3·5% |
| Physical inactivity | 1·4 (1·2–1·7) | 17·7% | 55·2% | 9·6% | 1·6% |
| Diabetes | 1·5 (1·3–1·8) | 6·4% | 71·4% | 3·1% | 1·1% |
| Air pollution | 1·1 (1·1–1·1) | 75·0% | 13·3% | 6·3% | 2·3% |
Data are relative risk (95% CI) or %. Overall weighted PAF=39·7%. PAF=population attributable fraction.
*
Weighted PAF is the relative contribution of each risk factor to the overall PAF when adjusted for communality.