Table 2 Characteristics of the included studies across different regions
International | North America | Europe/Oceania | East Asia | Middle Asia | South America | |
|---|---|---|---|---|---|---|
Number of trials | 56 | 56 | 15 | 5 | 5 | 3 |
Total sample size | 10,842 | 6855 | 799 | 457 | 98 | 159 |
Sample size per arm* | 135 (19, 639) | 102 (11, 746) | 40 (14, 153) | 37 (19, 268) | 20 (15, 25) | 18 (12, 129) |
Age, years* | 73.2 (68.3, 78.3) | 75.0 (58.0, 81.7) | 72.1 (64.6, 79.8) | 74.5 (69.0, 75.4) | 73.1 (67.7, 73.7) | 72.6 (71.7, 74.5) |
Gender, male (%)* | 40.3 (30, 59) | 45.0 (0, 98) | 38.0 (24.0, 53.3) | 31.8 (23.8, 37.0) | 52.1 (45, 60) | 38.9 (27.1, 41.7) |
APOE ε4 carrier, %* | 58.0 (0, 72) | 60.0 (41.3, 100) | 51.1 (44.0, 58.8) | 54.1** | N.A. | N.A. |
ADAS-cog 11, points* | 24.7 (18.9, 35.8) | 23.4 (13.1, 32.2) | 24.5 (15.4, 34.3) | 26.9 (23.9, 33.5) | 25.6 (17.1, 39.3) | 36.7 (29.3, 39.0) |
NPI score, points* | 10.3 (6.2, 21.8) | 8.65 (5.0, 16.1) | 9.2 (7.1, 11.2) | 9.1 (8.8, 9.3) | N.A. | N.A. |
MMSE score, points* | 19.4 (15.5, 22.9) | 20.3 (17.0, 25.4) | 19.3 (16.8, 23.6) | 16.1 (14.6, 16.6) | 13.2** | 17.4 (17.2, 17.6) |