. Author manuscript; available in PMC: 2025 Jan 1.

Published in final edited form as: Cerebrovasc Dis. 2023 Oct 23;53(4):382–390. doi: 10.1159/000533568

Table 3.

Change in DSST score per year of aging in unadjusted and adjusted models

	Unadjusted			Adjusted^*
	estimated DSST	95% CI	p value	estimated DSST	95% CI	p value
Estimated mean DSST score at age 77
No stroke	37.4	(36.9, 37.7)	ref	37.3	(36.9, 37.6)	ref
Stroke only	35.5	(33.8, 37.3)	0.042	36.2	(34.6, 37.6)	0.211
Stroke and HAI	36.0	(35.2, 36.9)	0.004	35.9	(35.2, 36.6)	0.001
Annual mean decline^a in DSST score
No stroke, per year	(0.65)	(0.61, 0.68)	<0.0001	0.63	(0.57, 0.66)	<0.0001
No stroke, per year-squared	(0.04)	(0.04, 0.05)	<0.0001	(0.04)	(0.04, 0.05)	<0.0001
Excess annual mean decline^a in DSST score
Stroke only versus no stroke	0.18	(0.02, 0.35)	0.025	0.17	(0.003, 0.33)	0.046
Stroke with HAI versus no stroke	0.28	(0.19, 0.36)	<0.0001	0.27	(0.19, 0.35)	<0.0001
Stroke with HAI versus stroke only	(0.09)	(−0.08, 0.26)	0.312	(0.10)	(−0.08, 0.27)	0.288

HAI, hospital-acquired infection; SD, standard deviation; DSST, Digit Symbol Substitution Test.

Adjusted analysis controls for: sex, race, education level, smoking status, hypertension, systolic blood pressure, diabetes, BMI, CHF, CHD, atrial fibrillation, dyslipidemia, and alcohol use.

Annual mean decline and excess annual mean decline are expressed as positive quantities. For example, in the adjusted model, participants without stroke experienced a mean decline in DSST score of 0.63 points/year and acceleration in mean decline of an additional 0.04 points/year-squared; and participants after stroke with HAI experienced a mean decline in DSST score of 0.27 points/year faster than those without stroke.