TABLE 4.
Diagnostic incidence of AD and ADRD by APOE genotype and race/ethnicity in the Multiethnic Cohort Study (1999‐2014; N = 16,034)
| Events | Person‐years | ASDIR | Hazard ratio (95% CI) | ||
|---|---|---|---|---|---|
| Model 1 | Model 2 | ||||
| (a) AD | |||||
| Number of ε4 allele = 0 | |||||
| African American | 167 | 24445 | 575.5 | 1.40 (1.08–1.81) | 1.33 (1.02–1.74) |
| Japanese American | 192 | 41205 | 422.1 | 0.99 (0.77–1.27) | 0.93 (0.71–1.20) |
| Latino | 109 | 23611 | 531.0 | 1.28 (0.96–1.69) | 1.12 (0.83–1.52) |
| Native Hawaiian | 43 | 14394 | 445.1 | 1.02 (0.70–1.46) | 0.92 (0.63–1.34) |
| White | 90 | 19202 | 420.7 | 1.00 (ref) | 1.00 (ref) |
| P for race/ethnicity | 0.0068 | 0.014 | |||
| Number of ε4 alleles = 1 or 2 | |||||
| African American | 172 | 13858 | 1152.8 | 1.12 (0.85–1.49) | 1.16 (0.87–1.54) |
| Japanese American | 81 | 9190 | 889.4 | 0.89 (0.64–1.23) | 0.91 (0.66–1.27) |
| Latino | 42 | 5900 | 913.1 | 0.93 (0.63–1.37) | 0.94 (0.62–1.42) |
| Native Hawaiian | 56 | 7850 | 1064.0 | 0.99 (0.69–1.41) | 1.05 (0.73–1.52) |
| White | 69 | 6730 | 1002.7 | 1.00 (ref) | 1.00 (ref) |
| P for race/ethnicity | 0.49 | 0.48 | |||
| P for race/ethnicity by APOE | 0.62 | 0.56 | |||
| (b) ADRD | |||||
| Number of ε4 allele = 0 | |||||
| African American | 460 | 23568 | 1729.3 | 1.46 (1.25–1.70) | 1.34 (1.14–1.58) |
| Japanese American | 482 | 40201 | 1134.7 | 0.92 (0.79–1.08) | 0.85 (0.73–1.00) |
| Latino | 270 | 23024 | 1390.2 | 1.14 (0.96–1.36) | 1.00 (0.83–1.20) |
| Native Hawaiian | 128 | 14077 | 1306.8 | 1.08 (0.87–1.34) | 0.96 (0.77–1.21) |
| White | 244 | 18734 | 1205.7 | 1.00 (ref) | 1.00 (ref) |
| P for race/ethnicity | < 0.0001 | < 0.0001 | |||
| Number of ε4 alleles = 1 or 2 | |||||
| African American | 361 | 13154 | 2698.5 | 1.30 (1.06–1.59) | 1.24 (1.00–1.52) |
| Japanese American | 171 | 8877 | 2070.5 | 1.03 (0.82–1.30) | 1.02 (0.81–1.29) |
| Latino | 98 | 5717 | 2291.0 | 1.14 (0.87–1.48) | 1.04 (0.78–1.38) |
| Native Hawaiian | 110 | 7669 | 2195.7 | 1.00 (0.77–1.29) | 0.99 (0.76–1.30) |
| White | 127 | 6455 | 1964.0 | 1.00 (ref) | 1.00 (ref) |
| P for race/ethnicity | 0.022 | 0.10 | |||
| P for race/ethnicity by APOE | 0.79 | 0.67 | |||
Note: P for race/ethnicity for the overall racial/ethnic difference was obtained from the Wald chi‐square test for the main effect of race/ethnicity in the sex‐combined Cox regression model for AD or ADRD stratified by the APOE ε4 risk allele carrier status. P for race/ethnicity by APOE for the heterogeneity of the racial/ethnic differences between non‐carriers and carriers of the APOE ε4 risk allele was obtained based on the interaction term between the APOE genotype trend variable and race/ethnicity in the combined Cox regression model for AD or ADRD.
ASDIR (age‐standardized diagnostic incidence rate per 1000 person‐years).
Model 1: Cox proportional hazards regression model adjusted for age at cohort entry and age at Medicare follow‐up start.
Model 2: includes Model 1 adjustments + education, history of heart disease, stroke, diabetes or hypertension at cohort baseline, and mean annual Medicare usage (in‐patient, out‐patient) over follow‐up.
Abbreviations: AD, Alzheimer's disease; ADRD, Alzheimer's disease and related dementia; CI, confidence interval.