Table 1b. Clinical characteristics of samples with ‘apparently' sporadic essential tremor from three different countries.
| Clinical features | German samples | French samples | Danish samples | All |
|---|---|---|---|---|
| Number of index cases | 84 | 3 | 10 | 97 |
| Men/women | 49/35 | 2/1 | 6/4 | 57/40 |
| Age at examination, years, mean±SD (range) | 61±15.7 (17–91) | 77±1.4 (76–78) | 75.9±5.6 (70–86) | 62.4±15.7 (17–91) |
| Age at onset, years, mean±SD (range) | 30.2±20.9 (2–80) | 42±31.1 (20–64) | NA | 30.6±21.1 (2–80) |
| AA | 29.4±19.9 (10–75) | 42±31.1 (20–64) | NA | |
| AG | 32.7±21.7 (5–80) | — | NA | |
| GG | 22.4±25.2 (2–65) | — | NA | |
| Tremor severitya, mean±SD (range)b | 7.3±4.2 (2–26) | 17.5±0.7 (17–18) | 5.4±1.9 (3–8) | 7.4±4.3 (2–26) |
| AA | 7.4±4.8 (3–26) | 17.5±0.7 (17–18) | 5.7±2.1 (3–8) | |
| AG | 7.2±3.6 (2–16) | — | 7±0 (7) | |
| GG | 8±3.3 (4–13) | — | 4±0 (4) | |
| Tremor duration, years, mean±SD (range) | 29.4±18.4 (5–70) | 35±32.5 (12–58) | ▽ | 29.5±18.6 (5–70) |
| AA | 30.9±18.2 (5–70) | 35±32.5 (12–58) | ▽ | |
| AG | 27.2±19.4 (5–60) | — | ▽ | |
| GG | 31.4±16.9 (12–50) | — | ▽ | |
| Alcohol responsiveness of tremor (%) | 35 (41.7) | NA | 5 (55.5) | 40 (42.1) |
NA, not available.
a
By Part A of the Fahn–Burke–Marsden tremor scale 16, ▽ in all Danish twins tremor duration ≥5 years.
b
No significant difference among each nation.