Table 1.
Clinical and pathological features of controls and essential tremor cases in the discovery and replicate cohorts.
| Discovery cohort | p-value | Replicate cohort | p-value | |||
|---|---|---|---|---|---|---|
|
|
|
|||||
| Controls | Essential tremor cases | Controls | Essential tremor cases | |||
| n | 16 | 16 | 25 | 61 | ||
| Age at death (years) | 82.5 ± 6.8 | 83.7 ± 7.4 | 0.638a | 67.2 ± 22.7 Median = 73.0 | 88.8 ± 5.9 Median = 90.0 | <0.001b |
| Gender | 0.716c | <0.001c | ||||
| Men | 7 (43.8%) | 5 (31.2%) | 20 (80.0%) | 22 (36.1%) | ||
| Women | 9 (56.2%) | 11 (68.8%) | 5 (20.0%) | 39 (63.9%) | ||
| Age of tremor onset (years) | NA | 32.5 ± 23.5 | NA | NA | 47.9 ± 20.6 Median = 55.0 | NA |
| Disease duration (years) | NA | 50.9 ± 23.4 | NA | NA | 40.8 ± 21.1 Median = 35.0 | NA |
| Total tremor score | NA | 24.0 ± 5.8 | NA | NA | 24.3 ± 6.6 | NA |
| Brain weight (grams) | 1190 ± 153 | 1214 ± 180 | 0.690 a | 1310 ± 178 | 1187 ± 124 | <0.001a |
| Postmortem interval (frozen, hours) | 18.4 ± 10.4 | 28.3 ± 8.1 | 0.005a | 20.3 ± 11.7 | 27.7 ± 12.5 | 0.019a |
| Braak AD score | 1.6 ± 1.0 Median = 2.0 | 2.1 ± 1.3 Median = 1.5 | 0.539b | 1.2 ± 1.4 Median = 1.0 | 2.4 ± 1.2 Median = 2.0 | <0.001b |
| CERAD plaque score d | 0.880c | 0.002c | ||||
| 0 | 6 (60.0%) | 10 (62.5%) | 16 (84.2%) | 20 (33.9%) | ||
| A | 4 (40.0%) | 4 (25.0%) | 1 (5.3%) | 18 (30.5%) | ||
| B | 0 (0.0%) | 1 (6.2%) | 2 (10.5%) | 15 (25.4%) | ||
| C | 0 (0.0%) | 1 (6.2%) | 0 (0.0%) | 6 (10.2%) | ||
| Purkinje cell counts | 11.2 ± 1.6 Median = 11.6 | 8.6 ± 1.8 Median = 8.6 | <0.001b | 11.4 ± 2.9 | 8.8 ± 1.5 | <0.001 a |
| Torpedo counts | 6.8 ± 9.2 Median = 3.0 | 12.9 ± 13.4 Median = 6.0 | 0.102b | 5.0 ± 3.9 Median = 4.0 | 16.5 ± 13.8 Median = 13.0 | <0.001 b |
| Dentate EAAT1 levels | 1.0 ± 0.4 | 1.2 ± 0.5 | 0.279a | |||
| Dentate EAAT2 levels | 1.0 ± 0.2 | 1.5 ± 0.6 | 0.007a | 1.0 ± 0.6 Median = 0.8 | 1.3 ± 0.8 Median = 1.1 | 0.022b |
| Cerebellar cortical EAAT2 levels | 1.0 ± 0.2 | 0.8 ± 0.2 | 0.045a | 1.0 ± 0.2 | 0.6 ± 0.2 | <0.001a |
| Dentate GFAP score | 2.4 ± 0.9 | 2.6 ± 1.0 | 0.668a | |||
Values represent mean ± standard deviation or number (percentage), and for variables that are not normally distributed, and the median is reported as well.
All the continuous measures were tested for normal distributions (Kolmogorov–Smirnov tests). For the normally distributed continuous measures, we used Student t-tests.
For non-normally distributed continuous measures, we used Mann-Whitney U tests.
Mean number of Purkinje cells (PCs) per 100× microscopic field, among 15 sampled fields.
NA = not applicable.
Values in bold are statistically significant.
Independent samples t-test.
Independent samples Mann-Whitney U test.
Chi-square test.
CERAD plaque scores of 6 controls in the discovery cohort and 12 controls and 11 ET cases in the replicate cohort were not available.