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Table 1 Study sample characteristics, overall, and by race in final analytic sample with imputed covariates (N = 1770), HANDLS 2004–2013

From: Race, APOE genotypes, and cognitive decline among middle-aged urban adults

 

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

Hypertensiona, %

46.1 ± 1.2

40.3 ± 1.8***d

50.8 ± 1.6

Diabetesa, %

   

 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

Dyslipidemiaa, %

28.8 ± 1.1

33.6 ± 1.8***d

24.9 ± 1.5

Cardiovascular diseasea, %

17.6 ± 0.9

15.2 ± 1.3*

19.7 ± 1.3

Co-morbidity indexa

3.46 ± 0.034

3.43 ± 0.05

3.48 ± 0.05

Cognitive performance at v1, unadjustedb

   

 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, unadjustedc

   

 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┼

  1. 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
  2. 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)
  3. 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
  4. bCrude baseline cognitive test score
  5. 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
  6. 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
  7. *p < 0.05; ** p < 0.01; *** p < 0.001, t-test for null hypothesis of no between-race differences
  8. ┼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
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Alzheimer's Research & Therapy

ISSN: 1758-9193