Table 1.

Summary of clinical assessments performed in this study.

Measurement			Statistics/Description
Medical history	Hypertension		13 subjects (68.4%)
	Diabetes		6 subjects (31.6%)
	Hypercholesterolemia		14 subjects (73.7%)
	Vascular risk factor		Combination of presences of hypertension, diabetes or hypercholesterolemia (rated from 0 to 3). 3/3/9/4 subjects were rated as 0/1/2/3.
Alzheimer’s Disease Centers’ Uniform Data Set v3 (UDS3)	Clinical Dementia Rating scale	Sum of Boxes (CDR-SB)	Normal (0)	10 subjects (52.6%)
			Questionable cognitive impairment (≥ 0.5, greater scores indicate more severe impairment)	9 subjects (47.4%)
		Global score (CDR-GS)	Normal (0)	10 subjects (52.6%)
			Questionable cognitive impairment (0.5)	9 subjects (47.4%)
	Montreal Cognitive Assessment (MoCA)		A measure of visuospatial construction, executive function, verbal memory, attention, working memory, language and orientation; Score ≥ 26 considered as normal (score range 0–30).
NIH toolbox	Flanker		The Flanker is a measure of attention and inhibitory control; Higher Flanker scores indicate higher level of ability to attend to relevant stimuli and inhibit attention from irrelevant stimuli.
	Dimensional Change Card Sort Test (DCCS)		The DCCS is a measure of cognitive flexibility; Higher DCCS scores indicate higher level of cognitive flexibility.
	Picture Sequence Memory Test (PSMT, version a and b)		The PSMT is a measure of episodic memory, which involves the acquisition, storage and effortful recall of new information; Higher PSMT scores indicate better episodic memory.
	Pattern Comparison Processing Speed Test (PCPS)		The PCPS is a measure of speed of processing for pattern comparison; Higher PCPS scores indicate faster speed of processing.
	Pegboard Dexterity Test (dominant hand)		The test records the time (seconds) required for a participant to place and remove nine plastic pegs into a plastic pegboard; Faster completion time indicates better manual dexterity.
	Grip Strength Test (dominant hand)		The test records the force (pounds) of a participant squeezing a digital hand dynamometer; Greater force indicates greater strength.
	4-meter Walking Gait Speed Test		The test records the time (seconds) required for a participant to walk 4 meters at usual pace; Shorter time indicates better gait speed, as a measure of bipedal motion.
White matter hyper-intensity (WMH)	Volume		Volume of WMH regions manually measured by clinical fellows from 3D T2 FLAIR images.
	Total Fazekas scale		Quantification of WMH lesions. Total Fazekas scale is the sum of two scales rated from 0 (absent) to 3 (large confluent areas) in periventricular white matter and deep white matter. 1/1/15/1/1 subjects were rated as 0/1/2/3/4.