Table 1.
Descriptive statistics of study subjects from the National Alzheimer’s Coordinating Center Uniform Data Set (Sept 2005-Jan 2011)
| Normal (n = 5,845)* | MCI (n = 3,010)* | Total (n = 8,855) | |
|---|---|---|---|
| Mean number visits (SD) | 3.3 (1) | 3.1 (1) | 3.3 (1) |
| Mean follow-up time in years (SD) | 2.7 (1) | 2.5 (1) | 2.6 (1) |
| Always depressed (all visits) | 709 (12) | 828 (28) | 1537 (17) |
| Never clinically depressed (all visits) | 4119 (70) | 1496 (50) | 5615 (63) |
| Initially depressed (subsequently improved) | 275 (5) | 166 (6) | 441 (5) |
| Intermittently depressed (during follow-up) | 742 (13) | 520 (17) | 1262 (14) |
| At baseline visit: | |||
| Age – mean (SD) | 72 (10) | 74 (9) | 73 (10) |
| Gender = Male – n (%) | 1998 (34) | 1458 (48) | 3456 (39) |
| Race = White – n (%) | 4853 (83) | 2449 (82) | 7302 (83) |
| Post-High School Education – n (%) | 4580 (79) | 2135 (70) | 6715 (76) |
| APOE4** | 1172 (30) | 848 (43) | 2020 (33) |
| Mean GDS (SD) | 1.7 (6) | 2.9 (7) | 2.1 (7) |
| GDS ≥5 n (%) | 366 (6) | 479 (16) | 845 (10) |
| Recent depression n (%)*** | 1064 (18) | 1063 (35) | 2127 (24) |
| In prior 2 years – n (%) | 964 (17) | 974 (33) | 1938 (21) |
| Clinician diagnosis of current depression - n (%) | 485 (8) | 583 (19) | 1068 (12) |
| Depression reported over 2 years ago – n (%) | 806 (14) | 449 (17) | 1305 (15) |
| Depression defined via NPI-Q | 685 (13) | 831 (29) | 1516 (18) |
| Stroke/TIA – n (%) | 405 (7) | 359 (12) | 764 (9) |
| Diabetes – n (%) | 602 (10) | 414 (14) | 1016 (12) |
| Cognitive and functional assessments – mean (SD) | |||
| Logical Memory | 13.6 (4) | 9.4 (4) | 12.2 (5) |
| MMSE | 28.9 (1) | 27.2 (2) | 28.3 (2) |
| CDR Sum | 0.1 (0) | 1.3 (1) | 0.5 (.9) |
| WAIS (digit-symbol) | 46.8 (13) | 36.9 (12) | 43.4 (14) |
| Category Fluency | 34.5 (9) | 27.0 (8) | 32.0 (9) |
| FAQ | 0.5 (2) | 3.7 (5) | 0.2 (.4) |
| Antidepressant Drug Use – n (%) | |||
| SSRI | 568 (10) | 625 (21) | 1193 (13) |
| Recent depression and taking SSRI – n (%) | 372 (6) | 463 (16) | 835 (9) |
| Non-selective/Other | 438 (7) | 348 (12) | 786 (9) |
| Recent depressed and taking other AD – n (%) | 248 (4) | 238 (8) | 486 (5) |
*
All subjects had at least 2 visits; 510 MCI-at-baseline subjects who reverted to normal during follow up, and 238 normal subjects who progressed to MCI but then reverted to normal, were excluded from analyses, resulting in analytic cohorts of 5,607 and 2,500 respectively.
**
APOE4 was available for 69% of the normal subjects and 66% if the MCI subjects.
***
Recent depression defined as clinician-diagnosed current depression (see methods).