Table 1. Demographic and Clinical Characteristics of 187 Cases.
| Probands (N = 59) | Affected Relatives (N = 128) | p | |
|---|---|---|---|
| Age (years) | 64.1±15.0, 22–91 | 60.5±17.2, 20–93 | 0.181 |
| Female gender | 38 (64.4) | 64 (50.0) | 0.072 |
| White race | 55 (93.2) | 121 (94.5) | 0.743 |
| Right-handed | 57 (96.6) | 117 (91.4) | 0.233 |
| Relationship to proband | NA | ||
| Self | 59 (100) | 0 (0.0) | |
| Child | 0 (0.0) | 33 (25.8) | |
| Sibling | 0 (0.0) | 57 (44.5) | |
| Parent | 0 (0.0) | 15 (11.7) | |
| Grandchild | 0 (0.0) | 3 (2.3) | |
| Aunt/uncle | 0 (0.0) | 4 (3.1) | |
| Nephew/niece | 0 (0.0) | 9 (7.0) | |
| Other (third-degree) | 0 (0.0) | 7 (5.5) | |
| Total tremor score (neurological examination) | 23.5±5.1, 12.5–35.5 | 18.7±5.0, 8.0–32.0 | <0.0011 |
| Intention tremor score4 | 0.85±0.63 (1.0), 0.0–2.0 | 0.59±0.56 (0.5), 0.0–2.0 | 0.0065 |
| Intention tremor6 | 32 (54.2) | 44 (34.4) | 0.012 |
| Tandem gait score | 2.89±3.62 (1.0), 0–10 | 2.40±3.66 (0.0), 0–10 | 0.1025 |
| Greater tandem gait difficulty7 | 13 (28.3) | 32 (29.1) | 0.922 |
| Currently takes daily medication for ET | 38 (64.4) | 33 (25.8) | <0.0012 |
| Age of tremor onset (years) | 22.4±14.8 | 30.9±19.2 | 0.0011 |
| Duration of tremor (years) | 41.7±18.3 | 30.2±17.9 | <0.0011 |
| Diabetes mellitus by history | 6 (10.2) | 17 (13.3) | 0.552 |
| Arthritis by history | 24 (40.7) | 43 (33.6) | 0.352 |
ET, Essential Tremor; NA, Not Applicable.
All values are mean±standard deviation (median), range or number (%), unless otherwise specified.
1
Student t-test.
2
Chi-square test.
3
Fisher exact test.
4
The intention tremor score (both arms combined) ranged from 0 to 2.
5
Mann–Whitney test.
6
Definite intention tremor in at least one arm or probable intention tremor in both arms.
7
Three or more mis-steps is the upper quartile of tandem mis-steps. Data absent for 31 study subjects.