Table 1. Demographic and clinical characteristics of cognitively intact individuals with MDD and age-matched comparison subjects at baseline.
| Characteristic | Comparison group (N=19) | MDD group (N=28) |
Statistical analysis |
||
|---|---|---|---|---|---|
| t | df | P | |||
| Age (years) | 68.1±7.3 | 66.5±5.4 | 0.835 | 45 | 0.41 |
| Education (years)a | 16.7±2.7 | 16.5±2.7 | 0.274 | 44 | 0.79 |
| Body mass index | 28.1±4.7 | 28.8±6.7 | 0.378 | 45 | 0.71 |
| 21-item HAM-D | 1.2±1.9 | 14.9±8.8 | 8.02 | 45 | <0.001 |
| MMSE | 29.5±0.5 | 29.8±0.6 | 1.56 | 45 | 0.13 |
| Total recall rating | 64.4±12.3 | 64.9±13.9 | 0.11 | 45 | 0.91 |
| Delayed recall rating | 8.5±2.8 | 9.5±2.5 | 1.258 | 45 | 0.22 |
| Trail-Making Test score | |||||
| Part A | 37.2±12.4 | 36.0±14.1 | 0.303 | 45 | 0.76 |
| Part B | 80.3 ±31.5 | 86.1±23.2 | 0.737 | 45 | 0.47 |
| Category fluency test | 41.7±8.1 | 40.6±8.2 | 0.45 | 45 | 0.66 |
| N (%) | N (%) | χ2 | df | P | |
| Diabetes | 4 (21) | 5 (18) | 0.08 | 1 | 0.79 |
| Female | 12 (63) | 10 (36) | 2.41 | 1 | 0.12 |
| Apolipoprotein ɛ level | |||||
| ɛ4 | 5 (26) | 11 (39) | 0.369 | 1 | 0.54 |
| ɛ2 | 6 (32) | 7 (25) | 0.03 | 1 | 0.87 |
| Family history of Alzheimer's disease | 6 (32) | 3 (11) | 3.3 | 1 | 0.07 |
| pg ml−1 | pg ml−1 | t | df | P | |
| Amyloid-β42 | 335.4±182.7 | 224.7±125.1 | 2.471 | 45 | 0.02 |
| Amyloid-β40 | 6518.0±2687.0 | 5146.0±2369.0 | 1.845 | 45 | 0.07 |
| Total tau proteinb | 328.7±151.7 | 273.0±114.3 | 1.422 | 44 | 0.16 |
| Phosphorylated tau protein | 51.6±20.9 | 48.9±25.9 | 0.371 | 45 | 0.71 |
Abbreviations: df, degrees of freedom; 21-item HAM-D, 21-item Hamilton Depression Rating Scale; MDD, major depressive disorder; MMSE, Mini-Mental State Examination. Bold P-values indicate statistically significant.
The data are mean±s.d. The data at baseline are from Pomara et al.26
a
Data for one control subject were not available.
b
Data for one MDD patient were not available.