Table 6.

Dual energy X-ray absorptiometry bone parameters in women.

Age (yr)

40–44 (n = 28)

45–49 (n = 32)

50–54 (n = 30)

55–59 (n = 31)

60–64 (n = 31)

65–69 (n = 33)

70–74 (n = 30)

75+ (n = 34)

β-Coefficient (95% CI)

R2

Unadjusted p-value

β-Coefficient (95% CI)

R2

Adjusted p-value

Whole body

aBMD (g/cm2)

1.1 ± 0.1(n=27)

1.1 ± 0.1

1.0 ± 0.1

1.0 ± 0.1(n=30)

1.0 ± 0.1

0.9 ± 0.1

0.9 ± 0.1(n=29)

0.9 ± 0.1(n=30)

−0.005 (−0.006, −0.005)

0.37

<0.0001

−0.004 (−0.005, −0.003)

0.54

<0.0001

BMC (g)

2,273 ± 361(n=27)

2,210 ± 366

2,081 ± 449

1,827 ± 300(n=30)

1,752 ± 252

1,749 ± 369

1,679 ± 368(n=29)

1,538 ± 303(n=30)

−18.9 (−22.5, −15.3)

0.31

<0.0001

−10.6 (−12.9, −8.2)

0.75

<0.0001

BA (cm2)

2,025 ± 193(n=27)

2,041 ± 229

1,974 ± 250

1,840 ± 201(n=30)

1,820 ± 165

1,839 ± 241

1,781 ± 231(n=29)

1,703 ± 227(n=30)

−8.7 (−11.0, −6.5)

0.20

<0.0001

−−2.8 (−4.0, −1.7)

0.83

<0.0001

Spine

aBMD (g/cm2)

1.1 ± 0.1(n=27)

1.0 ± 0.1

0.9 ± 0.2

0.8 ± 0.1(n=30)

0.8 ± 0.1

0.8 ± 0.2(n=32)

0.8 ± 0.1(n=29)

0.7 ± 0.1(n=31)

−0.008 (−0.01, −0.007)

0.34

<0.0001

−0.006 (−0.008, −0.005)

0.50

<0.0001

BMC (g)

53.3 ± 9.5(n=27)

48.7 ± 10.1

45.5 ± 10.1

37.6 ± 8.1(n=30)

38.2 ± 7.2

37.6 ± 10.2(n=32)

35.7 ± 9.2(n=29)

32.9 ± 8.5(n=31)

−0.5 (−0.6, −0.4)

0.29

<0.0001

−0.3 (−0.4, −0.2)

0.58

<0.0001

BA (cm2)

48.6 ± 3.6(n=27)

48.5 ± 4.9

48.5 ± 4.4

46.4 ± 5.4(n=30)

46.9 ± 4.3

47.7 ± 5.2(n=32)

45.6 ± 5.1(n=29)

44.9 ± 6.1(n=31)

−0.1 (−0.2, −0.1)

0.07

<0.0001

−0.007 (−0.05, 0.03)

0.47

0.734

Total hip

aBMD (g/cm2)

1.0 ± 0.2(n=27)

1.0 ± 0.1(n=30)

0.9 ± 0.1

0.8 ± 0.1(n=30)

0.8 ± 0.1(n=29)

0.7 ± 0.1(n=32)

0.7 ± 0.1(n=29)

0.7 ± 0.1(n=33)

−0.009 (−0.01, −0.008)

0.44

<0.0001

−0.008 (−0.009, −0.006)

0.51

<0.0001

BMC (g)

28.6 ± 5.0(n=27)

28.1 ± 4.8(n=30)

25.0 ± 4.5

23.0 ± 3.3(n=30)

22.0 ± 3.2(n=29)

21.9 ± 3.6(n=32)

20.9 ± 4.4(n=29)

19.2 ± 3.9(n=33)

−0.2 (−0.3, −0.2)

0.35

<0.0001

−0.2 (−0.2, −0.1)

0.51

<0.0001

BA (cm2)

28.3 ± 2.1(n=27)

28.5 ± 1.9(n=30)

28.8 ± 2.1

28.3 ± 2.0(n=30)

28.5 ± 1.9(n=29)

29.6 ± 2.3(n=32)

28.4 ± 2.3(n=29)

28.6 ± 2.3(n=33)

0.004 (−0.02, 0.03)

0.0005

0.719

0.04 (0.02, 0.06)

0.39

<0.0001

Femoral neck

aBMD (g/cm2)

1.0 ± 0.1(n=27)

1.0 ± 0.1(n=30)

0.9 ± 0.1

0.8 ± 0.1(n=30)

0.8 ± 0.1(n=29)

0.7 ± 0.1(n=32)

0.7 ± 0.1(n=29)

0.7 ± 0.1(n=32)

−0.008 (−0.01, −0.007)

0.45

<0.0001

−0.007 (−0.008, −0.006)

0.54

<0.0001

BMC (g)

4.1 ± 0.8(n=27)

4.0 ± 0.8(n=30)

3.6 ± 0.8

3.3 ± 0.7(n=30)

3.2 ± 0.6(n=29)

3.1 ± 0.7(n=32)

3.0 ± 0.7(n=29)

2.6 ± 0.7(n=32)

−0.04 (−0.04, −0.03)

0.29

<0.0001

−0.03 (−0.03, −0.02)

0.44

<0.0001

BA (cm2)

4.2 ± 0.7(n=27)

4.1 ± 0.6(n=30)

4.2 ± 0.6

4.1 ± 0.7(n=30)

4.1 ± 0.6(n=29)

4.2 ± 0.7(n=32)

4.2 ± 0.6(n=29)

3.9 ± 0.7(n=32)

−0.005 (−0.01, 0.002)

0.01

0.124

0.001 (−0.006, 0.008)

0.14

0.775

Radius

aBMD (g/cm2)

0.6 ± 0.1(n=27)

0.6 ± 0.1

0.6 ± 0.1

0.5 ± 0.1(n=29)

0.5 ± 0.1

0.4 ± 0.1

0.5 ± 0.1

0.4 ± 0.1(n=32)

−0.006 (−0.007, −0.005)

0.44

<0.0001

−0.005 (−0.005, −0.004)

0.58

<0.0001

BMC (g)

9.0 ± 1.5(n=27)

8.8 ± 1.2

8.3 ± 1.8

7.0 ± 1.2(n=29)

7.1 ± 1.3

6.8 ± 1.6

6.6 ± 1.4

6.1 ± 1.2(n=32)

−0.08 (−0.09, −0.06)

0.31

<0.0001

−0.05 (−0.06, −0.04)

0.60

<0.0001

BA (cm2)

14.5 ± 1.3(n=27)

15.0 ± 1.7

14.7 ± 1.8

14.8 ± 1.5(n=29)

15.0 ± 1.6

15.6 ± 1.2

14.7 ± 1.5

15.3 ± 1.9(n=32)

0.01 (−0.003, 0.03)

0.01

0.103

0.04 (0.03, 0.05)

0.41

<0.0001

Values are mean ± SD.

Bold indicates significance.

Adjustments were made for weight and height.

β-Coefficients are calculated with age as a continuous variable.

Superscript values indicate the group numbers.

aBMD, areal bone mineral density; BMC, bone mineral content; BA, bone area.