TABLE 2—
Age-Specific Incidence Rates per 1000 Person-Years for Dementia, Alzheimer’s Disease, and Non–Alzheimer’s Disease Dementia: Adult Changes in Thought Study, Northwestern United States, 1994–2010
| All Dementia Cases |
Alzheimer’s Disease Cases |
Non–Alzheimer’s Disease Dementia Cases |
|||||
| Age Group, Years | No. of Person-Years | No. of Cases | Rate (95% CI) | No. of Cases | Rate (95% CI) | No. of Cases | Rate (95% CI) |
| All participants | |||||||
| 65–69 | 1471 | 8 | 5.4 (2.7, 10.9) | 4 | 2.7 (1.0, 7.2) | 4 | 2.7 (1.0, 7.2) |
| 70–74 | 5525 | 52 | 9.4 (7.2, 12.4) | 30 | 5.4 (3.8, 7.8) | 22 | 4.0 (2.6, 6.0) |
| 75–79 | 6996 | 135 | 19.3 (16.3, 22.8) | 101 | 14.4 (11.9, 17.5) | 34 | 4.9 (3.5, 6.8) |
| 80–84 | 5858 | 272 | 46.4 (41.2, 52.3) | 211 | 36.0 (31.5, 41.2) | 61 | 10.4 (8.1, 13.4) |
| 85–89 | 3021 | 224 | 74.2 (65.1, 84.5) | 188 | 62.2 (54.0, 71.8) | 36 | 11.9 (8.6, 16.5) |
| ≥ 90 | 1181 | 124 | 105.0 (88.0, 125.2) | 105 | 88.9 (73.4, 107.6) | 19 | 16.1 (10.3, 25.2) |
| Male participants | |||||||
| 65–69 | 677 | 5 | 7.4 (3.1, 17.7) | 3 | 4.4 (1.4, 13.7) | 2 | 3.0 (0.7, 11.8) |
| 70–74 | 2367 | 27 | 11.4 (7.8, 16.6) | 13 | 5.5 (3.2, 9.5) | 14 | 5.9 (3.5, 10.0) |
| 75–79 | 2849 | 60 | 21.1 (16.4, 27.1) | 42 | 14.7 (10.9, 20.0) | 18 | 6.3 (4.0, 10.0) |
| 80–84 | 2275 | 112 | 49.2 (40.9, 59.2) | 79 | 34.7 (27.8, 43.3) | 33 | 14.5 (10.3, 20.4) |
| 85–89 | 1091 | 69 | 63.2 (49.9, 80.1) | 58 | 53.2 (41.1, 68.8) | 11 | 10.1 (5.6, 18.2) |
| ≥ 90 | 346 | 34 | 98.3 (70.2, 137.5) | 29 | 83.8 (58.2, 120.6) | 5 | 14.4 (6.0, 34.7) |
| Female participants | |||||||
| 65–69 | 795 | 3 | 3.8 (1.2, 11.7) | 1 | 1.3 (0.2, 8.9) | 2 | 2.5 (0.6, 10.1) |
| 70–74 | 3158 | 25 | 7.9 (5.3, 11.7) | 17 | 5.4 (3.3, 8.7) | 8 | 2.5 (1.3, 5.1) |
| 75–79 | 4147 | 75 | 18.1 (14.4, 22.7) | 59 | 14.2 (11.0, 18.4) | 16 | 3.9 (2.4, 6.3) |
| 80–84 | 3583 | 160 | 44.7 (38.2, 52.1) | 132 | 36.8 (31.1, 43.7) | 28 | 7.8 (5.4, 11.3) |
| 85–89 | 1929 | 155 | 80.3 (68.6, 94.0) | 130 | 67.4 (56.7, 80.0) | 25 | 13.0 (8.8, 19.2) |
| ≥ 90 | 835 | 90 | 107.8 (87.7, 132.5) | 76 | 91.0 (72.7, 113.9) | 14 | 16.8 (9.9, 28.3) |
Note. CI = confidence interval. The sample size was n = 3605.