Table 1 Characteristics^a of participants by quartile of leukocyte telomere length^b, 1999–2002

Age, years

55.4 (0.7)

48.5 (1.1)

42.4 (1.0)

37.9 (1.0)

<0.01

Non-Hispanic white, %

77.9 (3.1)

75.9 (2.5)

72.7 (2.9)

66.7 (2.9)

<0.01

Non-Hispanic black, %

7.7 (1.2)

8.6 (1.6)

8.7 (1.3)

13.2 (2.3)

0.01

Mexican-American, %

6.0 (1.3)

7.1 (1.2)

7.9 (1.2)

6.5 (1.2)

0.76

Women, %

45.3 (1.6)

53.0 (2.1)

51.2 (2.3)

51.7 (2.1)

0.04

<High school education, %

26.7 (1.4)

21.4 (1.5)

19.9 (1.8)

18.0 (1.6)

<0.01

High school education, %

25.3 (1.9)

28.9 (2.5)

25.6 (2.3)

27.6 (2.4)

0.67

>High school education, %

47.9 (2.0)

49.7 (2.6)

54.4 (2.7)

54.4 (2.7)

0.03

Household income < $20,000, %

26.5 (1.7)

21.2 (1.6)

21.9 (2.3)

26.8 (3.0)

0.81

Current smokers, %

22.1 (1.6)

26.1 (2.3)

24.6 (2.3)

26.6 (2.4)

0.22

Former smokers, %

32.9 (1.7)

28.6 (2.4)

23.4 (1.8)

21.1 (1.9)

<0.01

Never smokers, %

45.1 (2.0)

45.4 (1.8)

52.0 (2.4)

52.3 (3.1)

<0.01

Pack years smoked, mean years

29.5 (1.6)

25.2 (1.1)

19.5 (1.1)

14.5 (1.2)

<0.01

Consume alcohol, %

68.9 (1.6)

73.7 (2.9)

74.1 (3.1)

76.0 (3.4)

0.10

Body mass index, kg/m²

28.6 (0.3)

28.4 (0.3)

27.6 (0.3)

27.4 (0.3)

<0.01

C-reactive protein ≥1 mg/dL, %

12.9 (1.3)

10.1 (1.0)

7.8 (1.0)

8.7 (1.3)

0.04

Diabetes, %

12.9 (0.8)

11.0 (0.9)

7.1 (0.8)

6.6 (0.8)

<0.01

A1c, mean %

5.6 (0.03)

5.5 (0.03)

5.4 (0.03)

5.3 (0.03)

<0.01

A1c, mean mmol/mol

34 (0.3)

37 (0.3)

36 (0.3)

34 (0.3)

<0.01