Table 1.

Demographic characteristics of study participants

	Controls	PreHD	P-value
n	71	80	N/A
Age	49.59 ± 9.69	43.88 ± 8.87	0.0002
Sex (M:F)	29:42	38:42	0.4113
Study site	Leiden: 22 London: 22 Paris: 11 Vancouver: 16	Leiden: 25 London: 21 Paris: 17 Vancouver: 17	N/A
CAG	–	42.78 ± 2.24	N/A
DBS	–	303.22 ± 52.89	N/A

Group comparisons were made using t-tests (age, DBS) and chi square tests (sex). Significant differences (P < 0.05) are in bold.CAG = cytosine-adenine-guanine; DBS = disease burden score; N/A = not applicable; preHD = premanifest Huntington’s disease.