Table 3.
Estimated annual incidence rates of dementia with 95% confidence intervals (CI) for African Americans and Yoruba
| 1992 Cohort | 2001 Cohort | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Study Population |
Age Group | Predicted Cases |
Person-year | Rate (%) | 95% CI | Predicted Cases |
Person-year | Rate (%) | 95% CI | ||
| African Americans | 70–74 | 49 | 1705 | 2.9 | 2.1 | 3.8 | 12 | 2220 | 0.6* | 0.3 | 1.0 |
| 75–79 | 70 | 2194 | 3.2 | 2.5 | 4.0 | 33 | 2907 | 1.1* | 0.8 | 1.6 | |
| 80–84 | 69 | 1699 | 4.1 | 3.2 | 5.1 | 31 | 1634 | 1.9* | 1.3 | 2.7 | |
| 85+ | 78 | 1340 | 5.8 | 4.6 | 7.3 | 35 | 926 | 3.7 | 2.6 | 5.2 | |
| Overall^ | -- | -- | 3.6 | 3.2 | 4.1 | -- | -- | 1.4* | 1.2 | 1.7 | |
| Yoruba | 70–74 | 17 | 1748 | 1.0 | 0.6 | 1.5 | 27 | 3574 | 0.8 | 0.5 | 1.1 |
| 75–79 | 25 | 1699 | 1.5 | 1.0 | 2.2 | 35 | 3315 | 1.1 | 0.7 | 1.5 | |
| 80–84 | 30 | 1404 | 2.1 | 1.4 | 3.0 | 23 | 1162 | 2.0 | 1.2 | 2.9 | |
| 85+ | 44 | 1307 | 3.3 | 2.4 | 4.5 | 18 | 661 | 2.8 | 1.7 | 4.4 | |
| Overall^ | -- | -- | 1.7 | 1.4 | 2.0 | -- | -- | 1.4 | 1.1 | 1.6 | |
*
denotes significant difference in rates between the 1992 and 2001 African American cohorts.
^
Overall rates were standardized using the age distribution of 1990 United States census data for African Americans in Marion County.