Table 3.
Baseline Demographic, Clinical, and Neuroimaging Characteristics of Study Participantsa
| Characteristic | All Participants (N=740) | Cognitively Normal Controls (n=215) | MCI Nonconverters (n=217) | MCI Converters (n=140) | Patients With Alzheimer Disease (n=168) |
|---|---|---|---|---|---|
| Prospective follow-up time, median (IQR), mo | 12 (6–24) | 12 (6–24) | 12 (6–24) | 18 (6–24) | 12 (6–24) |
| Age, mean (SD), y | 75.3 (6.9) | 75.9 (5.5) | 75.3 (7.4) | 74.6 (6.8) | 75.5 (7.7) |
| Male sex, No. (%) | 303 (40.9) | 97 (45.1) | 74 (34.1) | 55 (39.3) | 81 (48.2) |
| Education level, median (IQR), y | 16 (14–18) | 16 (14–18) | 16 (13–18) | 16 (14–18) | 16 (12–17) |
| History of hypertension, No. (%) | 348 (47.0) | 97 (45.1) | 102 (47.0) | 69 (49.3) | 86 (51.2) |
| Smoking, No. (%) | 289 (39.0) | 78 (36.3) | 91 (41.9) | 55 (39.3) | 67 (39.9) |
| Alcohol abuse, No. (%) | 30 (4.1) | 5 (2.3) | 8 (3.7) | 7 (5.0) | 10 (5.9) |
| APOE ε2, minor allele frequency | 0.042 | 0.070 | 0.039 | 0.021 | 0.027 |
| APOE ε4, minor allele frequency | 0.367 | 0.142 | 0.290 | 0.432 | 0.430 |
| GDS score, median (IQR) | 1 (0–2) | 0 (0–1) | 1 (0–2) | 1 (1–2) | 1 (1–2) |
| ADAS-COG score, median (IQR) | 10.7 (6.8–15.0) | 6.0 (4.0–8.0) | 10.7 (7.3–13.0) | 13.0 (10.7–15.5) | 18.0 (14.2–22.2) |
| Mini-Mental State Examination score, median (IQR) | 27 (25–29) | 29 (29–30) | 28 (26–29) | 27 (25–28) | 23 (22–25) |
| Clinical Dementia Rating Sum of Boxes, median (IQR) | 1.5 (0.0–3.0) | 0.0 (0.0–0.0) | 1.5 (1.0–2.0) | 2.0 (1.0–2.5) | 4.0 (3.5–5.0) |
| White matter lesion volume, median (IQR), cm3 | 4.7 (3.2–7.4) | 4.0 (2.9–5.9) | 4.4 (3.1–7.5) | 5.1 (3.7–7.0) | 5.9 (4.1–10.2) |
| Amygdala volume, mean (SD), cm3 | 1.25 (0.22) | 1.38 (0.19) | 1.28 (0.20) | 1.16 (0.19) | 1.11 (0.18) |
| Hippocampal volume, mean (SD), cm3 | 3.23 (0.59) | 3.66 (0.50) | 3.28 (0.52) | 2.95 (0.48) | 2.85 (0.49) |
| Parahippocampal gyrus cortical thickness, mean (SD), mm | 2.34 (0.32) | 2.49 (0.28) | 2.36 (0.33) | 2.27 (0.27) | 2.18 (0.32) |
| Temporal pole cortical thickness, mean (SD), cm3 | 3.48 (0.13) | 3.66 (0.26) | 3.52 (0.32) | 3.37 (0.36) | 3.29 (0.39) |
| Entorhinal cortical thickness, mean (SD), mm | 3.09 (0.47) | 3.40 (0.30) | 3.16 (0.45) | 2.93 (0.43) | 2.73 (0.43) |
Abbreviations: ADAS-COG, Alzheimer Disease Assessment Scale Cognitive Subscale; GDS, Geriatric Depression Scale; IQR, interquartile range; MCI, mild cognitive impairment.
a
All reported values (except follow-up time) refer to baseline ascertainment procedures. All volumetric measurements were adjusted to intracranial volume. Reported follow-up times were assessed on December 1, 2009.