Table 2. Risk Factor Relative Risk and Communality.
| Risk factor | RR (95% CI)a | Communality, %b |
|---|---|---|
| Less education | 1.59 (1.26-2.01) | 72.0 |
| Hearing loss | 1.94 (1.38-2.73) | 83.5 |
| TBI | 1.84 (1.54-2.20) | 85.4 |
| Hypertension | 1.61 (1.16-2.24) | 53.4 |
| Excessive alcohol | 1.18 (1.06-1.31) | 59.8 |
| Obesity | 1.60 (1.34-1.92) | 65.9 |
| Smoking | 1.59 (1.15-2.20) | 63.5 |
| Depression | 1.90 (1.55-2.33) | 56.6 |
| Social isolation | 1.57 (1.32-1.85) | 43.3 |
| Physical inactivity | 1.39 (1.16-1.67) | 30.0 |
| Diabetes | 1.54 (1.33-1.79) | 54.5 |
| Air pollution | 1.09 (1.07-1.11) | 63.8 |
Abbreviations: ARIC, Atherosclerosis Risk in Communities; PCA, principal components analysis; RR, relative risks; TBI, traumatic brain injury.
a
Relative risks plus confidence intervals for each risk factor come from recent meta-analyses, as reported in the Lancet Commission.3
b
Communality is calculated using principal components analysis for ARIC data. The PCA identified 5 components with eigenvalues greater than one that together explained 61% of the variation among the 12 risk factors. Higher communality percentages indicate greater correlation with other risk factors. See Methods for more details.