Table 1.
Characteristics of ACT Participants Included in the Study
| 50-59 years | 60-69 years | 70-79 years | 80-89 years | |||||
|---|---|---|---|---|---|---|---|---|
| N | % | N | % | N | % | N | % | |
| Total participants | 1088 | - | 2852 | - | 2344 | - | 537 | - |
| Total participantsa | 916 | - | 2510 | - | 2092 | - | 478 | - |
| Total possible/probable AD eventsa | 53 | - | 412 | - | 538 | - | 107 | - |
| Total all-cause dementia eventsa | 66 | - | 514 | - | 647 | - | 117 | - |
| Years of follow up, median (25th, 75th) | 6 (3, 8) | 7 (4, 12) | 5 (2, 8) | 2 (1, 4) | ||||
| ACT cohort | ||||||||
| Original | 50 | 4.6 | 1253 | 43.9 | 1452 | 61.9 | 360 | 67.0 |
| Expansion | 199 | 18.3 | 537 | 18.8 | 512 | 21.8 | 118 | 22.0 |
| Replacement | 839 | 77.1 | 1062 | 37.2 | 380 | 16.2 | 59 | 11.0 |
| Age at start of follow up, median (25th, 75th) | 70 (68, 72) | 71 (70, 75) | 80 (80, 81) | 90 (90, 90) | ||||
| Female | 602 | 55.3 | 1626 | 57.0 | 1431 | 61.0 | 360 | 67.0 |
| Non Hispanic whiteb | 932 | 85.8 | 2498 | 87.6 | 2107 | 90.0 | 498 | 92.7 |
| Education beyond high school | 954 | 87.8 | 2111 | 74.0 | 1521 | 64.9 | 328 | 61.2 |
| ≥1 APOE ε4 alleles | 261 | 28.0 | 697 | 27.5 | 511 | 24.2 | 97 | 19.9 |
| Body mass index, median (25th, 75th) c | ||||||||
| Underweight | 10 | 0.9 | 18 | 0.6 | 10 | 0.4 | 3 | 0.6 |
| Normal | 233 | 21.4 | 647 | 22.7 | 672 | 28.7 | 203 | 37.8 |
| Overweight | 383 | 35.2 | 1205 | 42.3 | 1068 | 45.6 | 240 | 44.7 |
| Obese | 462 | 42.5 | 982 | 34.4 | 594 | 25.3 | 91 | 16.9 |
| Ever treated for hypertension | 375 | 34.5 | 1524 | 53.4 | 1618 | 69.0 | 438 | 81.6 |
| Ever treated for diabetes | 48 | 4.4 | 244 | 8.6 | 234 | 10.0 | 53 | 9.9 |
| Ever smoker | 538 | 49.5 | 1500 | 52.7 | 1153 | 49.3 | 225 | 42.0 |
| Early life SES: Financial difficult rating (1-10), median (25th, 75th) | 5 (3, 7) | 5 (3, 7) | 5 (4, 8) | 5 (4, 8) | ||||
| Statin prescription fill during age band | 60 | 5.5 | 506 | 17.7 | 632 | 27.0 | 215 | 40.0 |
| Number of cholesterol measures, median (25th, 75th) | 2 (1, 4) | 3 (2, 6) | 4 (2, 7) | 3 (1, 8) | ||||
| Average non-HDL cholesterol, median (25th, 75th) | 164 (139, 188) | 165 (141, 192) | 159 (134, 186) | 143 (121, 171) | ||||
| Average HDL cholesterol, median (25th, 75th) | 54 (44, 66) | 54 (44, 66) | 55 (46, 67) | 57 (48, 69) | ||||
Complete case analysis
In the 50-59 years age band, there were 41 blacks (3.8%), 41 Asian Americans (3.8%), 20 Hispanics (1.8%), and 52 people of other race groups (4.8%). In the 60-69 years age band, there were 114 blacks (4.0%), 123 Asian Americans (4.3%), 38 Hispanics (1.3%), and 77 people of other race groups (2.7%). In the 70-79 years age band, there were 80 blacks (3.4%), 89 Asian Americans (3.8%), 19 Hispanics (0.8%), and 47 people of other race groups (2.0). In the 80-89 years age band, there were 15 blacks (2.8%), 15 Asian Americans (2.8%), 4 Hispanics (0.7%), and 5 people of other race groups (0.9%).
Body mass index was computed as a predicted value for the midpoint of each age band using a linear mixed effects model of the BMI trajectories over time for all ACT participants.
Abbreviations: TC, total cholesterol; SES, socioeconomic status