Table 2.
Incidence Rate of All Dementia in NIA-LOAD/NCRAD Families
| Age Group, y | No. of Cases | No. of Person-years at Risk | Incidence Rate (95% CI) | Characteristic, Mean (SD) | |
|---|---|---|---|---|---|
| Educational Level, ya | Person-years at Riskb | ||||
| 65–74 | 36 | 1262 | 0.03 (0.02–0.04) | 13.8 (11.7) | 4.0 (2.0) |
| 75–84 | 58 | 894 | 0.07 (0.05–0.08) | 14.4 (14.1) | 3.7 (2.0) |
| ≥85 | 24 | 302 | 0.08 (0.05–0.12) | 13.0 (10.2) | 3.2 (1.9) |
Abbreviation: NIA-LOAD/NCRAD, National Institute on Aging Genetics Initiative for Late-Onset Alzheimer Disease/National Cell Repository for Alzheimer Disease.
a
We observed no significant difference between the education levels between the age-groups (F test, P = .60)
b
We observed no significant difference between the person-year distribution within the age groups (F test, P = .13).