Clinical and demographic information across groups^{^a}

	CN	HD	PreHD	EarlyHD	MidadvHD	P Value
No.	25	39	15	16	8
Age (yr)	38.6 ± 9.4	47.8 ± 13.6	37.8 ± 10.9	55.0 ± 11.8	52.3 ± 10.4	.004,^{^b} .81,^{^c} <.001,^{^d} .57^{^e}
Female sex (%)	36%	69%	80%	56%	75%	.01, .01, .16, .37
Education (yr)	12.1 ± 1.9	13.4 ± 5.7	16.4 ± 3.2	11.1 ± 5.2	12.5 ± 6.5	.24, <.001, .002, .61
CAG length	NA	43.1 ± 2.9	43.1 ± 2.9	42.6 ± 2.9	43.8 ± 2.9	NA, NA, .59, .31
DBS^{^f}	NA	339.6 ± 105.3	273.3 ± 108.9	364.5 ± 78.2	414.4 ± 78.1	NA, NA, .01, .15
Estimated yr to onset^{^g}	NA	NA	15.8 ± 7.8	NA	NA
TFC	NA	11.3 ± 3.0	12.9 ± 0.2	12.1 ± 0.9	6.4 ± 3.5	NA, NA, .004, <.001,
UHDRS-TMS	NA	20.6 ± 20.7	1.4 ± 1.5	23.6 ± 14.2	50.5 ± 8.3	NA, NA, <.001, <.001,
UHDRS-Cogscore	NA	220.6 ± 112.8	323.9 ± 48.4	189.4 ± 66.1	65.8 ± 60.2	NA, NA, <.001, <.001,
Apathy score^{^h}	NA	4.9 ± 5.3	2.5 ± 3.7	4.6 ± 5.4	9.8 ± 4.7	NA, NA, = .2, .03
FAS	NA	28.5 ± 17.3	43.6 ± 12.4	22.7 ± 12.3	9.7 ± 6.4	NA, NA, <.001, .01
SDMT	NA	35.1 ± 20.1	54.7 ± 8.4	27.7 ± 12.9	9.8 ± 8.1	NA, NA, <.001, .001
Semantic fluency	NA	16.4 ± 7.0	23.0 ± 4.2	14.3 ± 3.5	7.1 ± 3.3	NA, NA, <.001, .001
Stroop Color	NA	51.6 ± 28.9	75.5 ± 20.6	44.3 ± 17.8	16.8 ± 19.5	NA, NA, <.001, .01
Stroop Word	NA	71.9 ± 34.5	99.2 ± 19.1	68.1 ± 21.7	22.0 ± 22.4	NA, NA, <.001, .001
TMT (parts B-A)	NA	−4.6 ± 8.0	0.3 ± 0.7	−3.6 ± 5.1	−17.6 ± 8.5	NA, NA, .008, .004
TMT cognitive flexibility	NA	1.5 ± 1.4	1.1 ± 1.1	2.0 ± 1.4	1.0 ± 1.4	NA, NA, .07, .15

Note:—NA indicates not available; TFC, Total Functional Capacity; TMS, Total Motor Score; Cogscore, Cognitive Score; FAS, F-A-S test of verbal fluency.
↵a Values are expressed as mean ± standard deviation.
↵b CN vs HD.
↵c CN vs preHD.
↵d PreHD vs earlyHD.
↵e EarlyHD vs midadvHD.
↵f DBS = 9.
↵g Derived from 10.
↵h Derived from 23.