Table 1.
Summary of participant characteristics
| Control | Premanifest HD* | Early HD | |
| No of participants† | 116 | 117 | 116 |
| Age (years)‡ | |||
| Mean (SD) | 46.2 (10.2) | 40.8 (8.9) | 49.2 (9.7) |
| Range | 23.0–65.7 | 18.6–64.1 | 22.8–64.1 |
| Gender | |||
| Women (n (%)) | 65 (56.0) | 64 (54.7) | 63 (54.3) |
| Men (n (%)) | 51 (44.0) | 53 (45.3) | 53 (45.7) |
| Education§ | |||
| Mean (SD) | 4.0 (1.3) | 4.0 (1.2) | 3.7 (1.3) |
| CAG length¶ | |||
| Mean (SD) | – | 43.1 (2.4) | 43.6 (3.0) |
| Range | – | 39–52 | 39–59 |
| Disease burden score‡** | |||
| Mean (SD) | – | 293.8 (47.6) | 375.5 (74.3) |
*
This group had an estimated median of 10.8 years to onset.
†
Number of participants in the TRACK-HD study with at least one follow-up measure on at least one of the 12 cognitive tasks featured in this paper.
‡
Age and disease burden score as measured at baseline.
§
Education level was reported according to the ISCED education classification system.8
¶
Two premanifest and three early HD participants had CAG repeats of 39, the remainder were all ≥39.
**
Disease burden score = age × (CAG length–35.5).
HD, Huntington's disease.