Table 4 Baseline characteristics for subgroups (data on Q₁, additional data on biomarkers M/N, and on replicates Q₂ and Q₃); ARIC, 1987

n

%

n

%

n

%

White

6,387

81.5

2,251

100*

501

79.0

Female

4,269

54.6

1,141

50.7*

293

46.2*

Age(years)

   50–54

2,904

37.2

896

39.8*

179

28.2*

   55–59

2,619

33.5

743

33.0

247

38.9

   60+

2,291

29.3

612

27.2

208

32.8

Education

   Less than High school

1,580

20.2

150

6.7*

141

22.3

   High school graduate

2,658

34.1

814

36.2

189

29.9

   More than High school

3,567

45.7

1,286

57.2

303

47.9

Apo E ε4 allele

2,249

30.0

614

28.8

164

27.0

Body Mass Index (kg per m²)

   <25.00

2,596

33.2

760

33.8*

220

34.7

   25.0–29.9

3,220

41.2

962

42.8

274

43.2

   ≥ 30

1,995

25.5

528

23.5

140

22.1

Smoking status

   Current smoker

1,555

19.9

400

17.8*

136

21.4

   Former smoker

2,776

35.5

941

41.8

227

35.8

   Never smoked

3,478

44.5

909

40.4

271

42.7

Mean

(SD)

Mean

(SD)

Mean

(SD)

Alcohol (g/d)

5.9

(12.7)

8.1

(13.5)*

5.6

(11.2)

Caffeine (mg/day)

291.04

(290.82)

348.08

(325.93)*

313.36

(297.42)*

Physical activity scale

7.06

(1.39)

7.33

(1.33)*

7.10

(1.48)

Energy intake (kcal/day)

1578

(571)

1581

(559)

1620

(566)

Vitamin A (1000 IUs/day)

9.1

(7.0)

8.6

(6.8)*

9.2

(7.3)

Vitamin B₆ (mg/day)

1.75

(0.67)

1.74

(0.66)

1.75

(0.68)

Vitamin B₁₂ (mcg/day)

7.61

(4.23)

7.06

(3.50)*

7.97

(4.32)*

Vitamin C (mg/day)

122

(81)

113

(70)*

122

(86)

Vitamin E (mg/day)

5.0

(3.1)

4.7

(3.0)*

5.1

(3.4)

Folate (mcg/day)

232.59

(101.18)

218.48

(94.97)*

235.03

(102.66)