Table 1.
Comparison of APOE ε4 allele as a marker for AD in various studies.
| Reference | Disease comparison (ethnic group)a | No. of cases (AD/non-AD) | APOE ε4 allele carrier type | Specificity (95% CI) | Sensitivity (95% CI) | PPV/NPV | OR (95% CI) |
|---|---|---|---|---|---|---|---|
| Farrer et al. (24) | AD versus HC (Caucasian) | (193/6,262) | Homozygous | N/A | N/A | N/A | 12.5 (8.8–17.7) |
| AD versus HC (African American) | (34/240) | Homozygous | N/A | N/A | N/A | 5.7 (2.3–14.1) | |
| AD versus HC (Hispanics) | (12/267) | Homozygous | N/A | N/A | N/A | 2.2 (0.7–6.7) | |
| AD versus HC (Japanese) | (45/1,977) | Homozygous | N/A | N/A | N/A | 33.1 (13.6–80.5) | |
| Saunders et al. (26) | AD versus HC | (46/10) | Heterozygous | 1 | 0.75 | 1.0/0.42 | N/A |
| AD versus HC | (11/10) | Homozygous | 1 | 0.19 | 1/0.18 | N/A | |
| Elias-Sonnenschein et al. (27) | AD versus MCI | (35/35) | Heterozygous | 0.67 (0.62–0.71) | 0.53 (0.46–0.61) | 0.43/0.75 | 2.29 (1.88–2.80) |
| AD versus MCI | (9/9) | Homozygous | 0.93 (0.90–0.97) | 0.21 (0.10–0.33) | 0.59/0.89 | 3.94 (2.09–7.33) | |
| Vos et al. (28, 29) | AD versus naMCI | (73/226) | N/A | 0.62 (0.53–0.71) | 0.56 (0.37–0.74) | 0.25/0.86 | 1.8 (0.7–4.7) |
| AD versus aMCI | (158/399) | N/A | 0.57 (0.49–0.64) | 0.56 (0.46–0.66) | 0.40/0.71 | 1.8 (1.1–3.0) |
AD, Alzheimer’s disease; aMCI, amnestic mild cognitive impairment; APOE, apolipoprotein E; HC, healthy control; MCI, mild cognitive impairment; naMCI, non-amnestic mild cognitive impairment; OR, odds ratio; PPV/NPV, positive predictive value/negative predictive value.
aEthnic group included if only a particular group was studied.