Table 4.

Associations Between Heart Rate Variability and Exam 5 Digit Span (Total) Scores From Linear Regression Models

	Model 1			Model 2
	β	95% CI	P Value	β	95% CI	P Value
SDNN
Exam 1	0.15	−0.02–0.32	0.093	0.09	−0.08–0.27	0.276
Exam 5	0.22	0.06–0.37	0.007	0.17	0.01–0.33	0.034
Change	0.07	−0.07–0.21	0.330	0.08	−0.06–0.22	0.272
RMSSD
Exam 1	0.13	−0.03–0.29	0.108	0.08	−0.08–0.24	0.336
Exam 5	0.14	−0.01–0.29	0.068	0.11	−0.04–0.26	0.160
Change	0.07	−0.07–0.22	0.325	0.09	−0.05–0.24	0.201

Model 1 adjusted for age, race, sex, and education level. Model 2 additionally adjusted for systolic blood pressure, Center for Epidemiological Studies Depression scale score, smoking status, body mass index, physical activity, antihypertensive and antiarrhythmic medication use, diabetes mellitus, APOE genotype, and incident myocardial infarction, heart failure, and stroke/ transient ischemic attack. β represents regression coefficients for log2‐transformed HRV values. APOE indicates apolipoprotein E; CESD, Center for Epidemiological Studies Depression scale; RMSSD, root mean square of successive differences; SDNN, SD of normal‐normal intervals; and TIA, transient ischemic attack.