Table 3 Risk factor trends by birth cohort and ethnic group

Number

157

375

347

18222*

21,111

12,424

Age range (y)

60-73

49-64

46-55

60-73*

49-64

46-55

Age at menarche (y)^a

13.2 (1.6)

13.3 (1.7)

13.2 (1.6)

0.6

12.9 (1.6)

13.0 (1.5)

13.0 (1.7)

0.002

Body mass index^a

25.8 (4.6)

27.6 (5.0)

27.3 (5.7)

0.29

27.3 (5.1)

27.2 (5.4)

27.4 (5.7)

< 0.001

Weight (kg)^a

63.0 (11.5)

69.4 (14.1)

66.7 (13.9)

0.8

70.6 (13.6)

71.0 (14.7)

72.7 (15.5)

< 0.001

Height (m)^a

1.56 (0.06)

1.59 (0.06)

1.56 (0.07)

0.047

1.61 (0.06)

1.61 (0.06)

1.63 (0.07)

< 0.001

Nulliparous^b

6.3%

10.3%

13.1%

0.15

10.2%

15.4%

17.0%

< 0.001

≥4 children^b

31.5%

25.9%

22.1%

0.004

12.3%

7.5%

8.1%

< 0.001

Age at first child (y)^a

24.8 (5.2)

23.8 (4.9)

25.7 (5.1)

0.005

23.6 (4.3)

24.3 (5.2)

25.4 (5.6)

< 0.001

1st child <17y^b

1.1%

2.3%

2.0%

0.18

0.8%

2.5%

2.3%

< 0.001

Number children (n)^a

2.9 (1.6)

2.9 (2.0)

2.3 (1.7)

< 0.001

2.2 (1.3)

2.0 (1.2)

1.9 (1.3)

< 0.001

≥1 affected 1st-degree relative (%)^b

15.1%

6.9%

6.4%

0.35

12.4%

9.7%

13.3%

0.11

Adult weight gain (%)^a

27.8 (20.2)

31.1 (22.6)

33.3 (25.6)

0.9

24.7 (21.4)

24.2 (20.9)

22.8 (20.5)

< 0.001

Physical activity (y/n)^b

52.0%

51.5%

39.9%

0.35

75.2%

73.8%

62.3%

< 0.001

Physical activity(> 17 h/month)^b

60.2%

61.5%

43.7%

0.074

70.7%

58.5%

52.1%

< 0.001

Drink alcohol (y/n)^b

20.4%

16.3%

14.2%

0.6

68.1%

77.9%

75.1%

< 0.001