. 2021 Jun 30;13:120. doi: 10.1186/s13195-021-00855-y

Table 1.

Study sample characteristics, overall, and by race in final analytic sample with imputed covariates (N = 1770), HANDLS 2004–2013

	Overall	Whites	African American
	(X ± SE), %	(X ± SE), %	(X ± SE), %
	(N = 1770)	(N = 794)	(N = 976)
APOE genotype, %
ε3/ε3	51.1 ± 1.2	61.1 ± 1.7	43.0 ± 1.6
ε2/ε2	0.7 ± 0.2	0.5 ± 0.3	0.9 ± 0.3
ε2/ε3	14.9 ± 0.8	12.6 ± 1.2^***d	16.7 ± 1.2
ε2/ε4	4.0 ± 0.5	2.4 ± 0.5^***d	5.2 ± 0.7
ε3/ε4	25.4 ± 1.0	21.2 ± 1.4^***d	28.9 ± 1.5
ε4/ε4	3.9 ± 0.5	2.3 ± 0.5^***d	5.2 ± 0.7
APOE2 allelic dosage
0	80.5 ± 0.9	84.5 ± 1.3	77.2 ± 1.3
1	18.8 ± 0.9	15.0 ± 1.3^***d	21.9 ± 1.3
2	0.7 ± 0.2	0.5 ± 0.3	0.9 ± 0.3
X ± SE
APOE4 allelic dosage
0	66.7 ± 1.1	74.2 ± 1.6	60.7 ± 1.6
1	29.4 ± 1.1	23.6 ± 1.5^***d	34.1 ± 1.5
2	3.9 ± 0.5	2.3 ± 0.5^***d	5.2 ± 0.7
X ± SE
Baseline socio-demographic, SES, and health-related variables
Sex, % male	42.8 ± 1.2	43.7 ± 1.8	42.1 ± 1.6
Age at v₁, years	48.496 ± 0.218	48.606 ± 0.325	48.406 ± 0.294
African American, %	55.1 ± 1.2	0.000	100.0
Poverty status, % < 125% of the 2004 federal poverty guidelines	38.9 ± 1.2	31.0 ± 1.6^***	45.3 ± 1.6
Education, completed, %
< HS	5.9 ± 0.6	8.5 ± 1.0^***d	3.9 ± 0.6
HS	59.1 ± 1.2	55.9 ± 1.8	61.9 ± 1.6
> HS	34.8 ± 1.1	35.7 ± 1.7	34.2 ± 1.5
Literacy, WRAT-3 score	42.6 ± 0.2	44.8 ± 0.3^***d	40.8 ± 0.2
Baseline drug and tobacco use
Any drug, current user, %	17.5 ± 0.9	13.1 ± 1.2^***d	21.0 ± 1.4
Tobacco, current user, %	44.8 ± 1.2	43.1 ± 1.8	46.2 ± 1.6
Body mass index, kg/m²	30.1 ± 0.2	30.3 ± 0.3	30.0 ± 0.3
Self-rated health, %
Poor/average	24.1 ± 1.0	26.7 ± 1.6^**d	21.9 ± 1.3
Good	41.7 ± 1.2	37.5 ± 1.7	45.2 ± 1.6
Very good/excellent	34.2 ± 1.1	35.8 ± 1.7^*d	32.9 ± 1.5
HEI-2010 total score at v₁	42.5 ± 0.3	42.2 ± 0.5	42.8 ± 0.4
Total energy intake, kcal/day	2018 ± 24	2035 ± 38	2003 ± 35
CES-D total score	14.9 ± 0.3	15.5 ± 0.4^*d	14.4 ± 0.4
Hypertension^a, %	46.1 ± 1.2	40.3 ± 1.8^***d	50.8 ± 1.6
Diabetes^a, %
No	64.3 ± 1.1	63.3 ± 1.7	65.1 ± 1.5
Pre-diabetic	18.6 ± 0.9	20.8 ± 1.5	16.9 ± 1.2
Diabetic	17.1 ± 0.9	16.0 ± 1.3	18.1 ± 1.2
Dyslipidemia^a, %	28.8 ± 1.1	33.6 ± 1.8^***d	24.9 ± 1.5
Cardiovascular disease^a, %	17.6 ± 0.9	15.2 ± 1.3*	19.7 ± 1.3
Co-morbidity index^a	3.46 ± 0.034	3.43 ± 0.05	3.48 ± 0.05
Cognitive performance at v₁, unadjusted^b
MMSE, non-normalized	27.772 ± 0.051	28.163 ± 0.075^***d	27.454 ± 0.069
MMSE, normalized	76.7 ± 0.37	80.3 ± 0.56^***d	73.8 ± 0.48
CVLT-List A	24.635 ± 0.167	26.044 ± 0.263^***d	23.541 ± 0.207
CVLT-DFR	7.321 ± 0.079	8.131 ± 0.121^***d	6.690 ± 0.099
BVRT	6.339 ± 0.118	6.062 ± 0.167^*	6.566 ± 0.166
BTA	6.692 ± 0.055	7.199 ± 0.079^***d	6.287 ± 0.072
AF	18.866 ± 0.127	19.776 ± 0.198^***d	18.125 ± 0.160
DS-F	7.317 ± 0.052	7.633 ± 0.081^***d	7.058 ± 0.067
DS-B	5.692 ± 0.052	6.234 ± 0.083^***d	5.246 ± 0.063
CDT	8.799 ± 0.029	8.972 ± 0.041^***d	8.656 ± 0.039
TRAILS A	36.392 ± 0.915	31.690 ± 0.831^***d	40.246 ± 1.508
TRAILS B	143.723 ± 3.702	111.639 ± 4.573^***d	170.019 ± 5.455
Annualized rate of cognitive change, unadjusted^c
MMSE, non-normalized	− 0.0116 ± 0.0103	− 0.0055 ± 0.0149	− 0.0101 ± 0.0141
MMSE, normalized	− 0.1941 ± 0.0847^┼	− 0.1596 ± 0.1315	− 0.1570 ± 0.1111
CVLT-List A	− 1.353 ± 0.0430^┼	− 1.4380 ± 0.0719^┼	− 1.2940 ± 0.05259^┼
CVLT-DFR	− 0.4505 ± 0.0179^┼	− 0.4804 ± 0.0296^┼	− 0.4258 ± 0.02214^┼
BVRT	+ 0.4659 ± 0.0266^┼	+ 0.3166 ± 0.0358^┼,***,d	+ 0.5669 ± 0.0375^┼
BTA	− 0.0618 ± 0.01243^┼	− 0.0803 ± 0.0192^┼	− 0.0447 ± 0.0163^┼
AF	+ 0.0132 ± 0.0242	+ 0.0400 ± 0.0402	+ 0.0025 ± 0.0298
DS-F	− 0.0139 ± 0.0102	− 0.0008 ± 0.0169	− 0.0196 ± 0.0128
DS-B	− 0.0067 ± 0.0103	+ 0.0071 ± 0.0164	− 0.0113 ± 0.0132
CDT	− 0.0155 ± 0.0075^┼	− 0.0200 ± 0.0115	− 0.00958 ± 0.00990
TRAILS A	+ 0.4719 ± 0.2897	+ 0.3703 ± 0.2800	+ 0.3995 ± 0.4610
TRAILS B	+ 4.0767 ± 0.8128^┼	+ 2.298 ± 1.015^┼	+ 5.0957 ± 1.1905^┼

Abbreviations: AF animal fluency, APOE Apolipoprotein E genotype, BMI body mass index, BTA Brief Test of Attention, BVRT Benton Visual Retention Test, CDT Clock Drawing Test, CES-D Center for Epidemiologic Studies-Depression, CVLT-DFR California Verbal Learning Test-Delayed Free Recall, CVLT-List A California Verbal Learning Test-List A, DS-B Digits Span-Backward, DS-F Digits Span-Forward, HANDLS Healthy Aging in Neighborhood of Diversity across the Lifespan, HEI-2010 Healthy Eating Index, 2010 version, HS High school, MMSE Mini-Mental State Examination, SD standard deviation, TRAILS A Trailmaking Test, Part A, TRAILS B Trailmaking Test, part B, WRAT-3 Wide Range Achievement Test, 3rd revision, X mean

Values are means (X) ± SE for continuous variables and % for categorical variables. The sample selected has complete data on MMSE and 10 other cognitive test scores at visits 1 and/or 2 and complete data on APOE genotypes. Other covariates were multiple imputed (5 imputations with 10 iterations), using chained equations. All cognitive test scores are in the direction of higher score ➔ better performance with the exception of BVRT (# of errors) and TRAILS A and B (# of sec. to complete)

^aThe co-morbidity index was calculated as the sum of hypertension, diabetes, and dyslipidemia (or statin use), and self-reported history of cardiovascular disease included atrial fibrillation, angina, coronary artery disease, congestive heart failure, or myocardial infarction, ranging from 0 to 5

^bCrude baseline cognitive test score

^cCrude estimated annual rate of change in cognitive performance based on mixed-effects linear regression model with TIME as the only covariate. Difference by race was determined by interacting TIME with race

^dp < 0.05 upon further adjustment for age, sex, and poverty status in multiple linear, logistic, multinomial logit, or mixed-effects linear regression models with race entered as the main predictor

*p < 0.05; ** p < 0.01; *** p < 0.001, t-test for null hypothesis of no between-race differences

^┼p < 0.05, t-test for null hypothesis of γ₁ = 0 (fixed effects coefficient for TIME) in mixed-effects linear regression models with TIME as the only variable