Skip to main content

Table 3 The association between body mass index and breast cancer by age at diagnosis in premenopausal women at baseline

From: Body mass index and breast cancer risk in premenopausal and postmenopausal East Asian women: a pooled analysis of 13 cohort studies

 

Body mass index at baseline (kg/m2)

 < 18.5

18.5– < 21

21– < 23

23– < 25

25– < 27.5

27.5- < 30

30-

Trend (per 5 kg/m2)

 

HR (95% CI)

HR (95% CI)

HR

HR (95% CI)

HR (95% CI)

HR (95% CI)

HR (95% CI)

HR (95% CI)

p

Breast cancer that developed before 50 years of age

Number of participants

5,571

25,518

29,294

23,556

14,804

5,566

2,484

  

Person-years

48,597

194,531

197,523

146,036

86,777

31,975

14,699

  

Number of cases

24

160

161

122

91

26

15

  

Crude rate (per 100,000)

49.39

82.25

81.51

83.54

104.87

81.31

102.05

  

Age- and study-adjusted (HR1)

0.85 (0.55–1.31)

1.15 (0.92–1.43)

1 (ref.)

0.97 (0.77–1.23)

1.19 (0.92–1.54)

0.92 (0.61–1.39)

1.19 (0.70–2.02)

1.02 (0.89–1.17)

0.80

Multivariate-adjusted (HR2)a

0.84 (0.55–1.29)

1.14 (0.92–1.42)

1 (ref.)

0.97 (0.77–1.23)

1.19 (0.92–1.54)

0.91 (0.60–1.38)

1.18 (0.69–2.00)

1.02 (0.89–1.17)

0.78

Multivariate-adjusted (HR3)b

0.84 (0.55–1.30)

1.15 (0.92–1.43)

1 (ref.)

0.97 (0.77–1.23)

1.19 (0.92–1.54)

0.91 (0.60–1.37)

1.18 (0.69–2.00)

1.02 (0.89–1.16)

0.81

(Excluding cases within 3 years)

Multivariate-adjusted (HR2)a

0.80 (0.44–1.48)

1.02 (0.75–1.40)

1 (ref.)

0.93 (0.67–1.30)

1.09 (0.75–1.59)

1.13 (0.66–1.93)

0.65 (0.24–1.77)

1.02 (0.84–1.23)

0.86

Multivariate-adjusted (HR3)b

0.80 (0.44–1.48)

1.02 (0.75–1.40)

1 (ref.)

0.93 (0.67–1.30)

1.10 (0.76–1.60)

1.13 (0.66–1.93)

0.66 (0.24–1.80)

1.02 (0.84–1.24)

0.84

Breast cancer that developed after 50 years of age

Number of participants

5147

24,698

29,973

25,109

16,544

6263

2806

  

Person-yearsc

66,481

315,425

392,348

337,587

228,903

87,644

38,987

  

Number of cases

68

310

417

374

279

109

46

  

Crude rate (per 100,000)

102.28

98.28

106.28

110.79

121.89

124.37

117.99

  

Age- and study-adjusted (HR1)

0.94 (0.72–1.22)

0.91 (0.79–1.06)

1 (ref.)

1.03 (0.90–1.19)

1.14 (0.98–1.32)

1.15 (0.93–1.42)

1.09 (0.80–1.48)

1.10 (1.02–1.19)

0.02

Multivariate-adjusted (HR2)a

0.94 (0.73–1.23)

0.92 (0.79–1.06)

1 (ref.)

1.03 (0.90–1.19)

1.14 (0.98–1.33)

1.15 (0.93–1.42)

1.10 (0.81–1.49)

1.10 (1.02–1.19)

0.02

Multivariate-adjusted (HR3)b

0.90 (0.69–1.16)

0.90 (0.78–1.04)

1 (ref.)

1.04 (0.91–1.20)

1.16 (0.99–1.35)

1.17 (0.94–1.44)

1.10 (0.81–1.49)

1.12 (1.04–1.21)

0.004

(Excluding cases within 3 years)

Multivariate-adjusted (HR2)a

0.94 (0.72–1.22)

0.93 (0.80–1.08)

1 (ref.)

1.04 (0.90–1.20)

1.17 (1.01–1.37)

1.18 (0.95–1.46)

1.11 (0.81–1.52)

1.11 (1.03–1.20)

0.009

Multivariate-adjusted (HR3)b

0.89 (0.68–1.16)

0.91 (0.79–1.06)

1 (ref.)

1.05 (0.91–1.21)

1.19 (1.02–1.39)

1.19 (0.96–1.48)

1.11 (0.81–1.52)

1.13 (1.05–1.22)

0.002

  1. HR hazard ratio, CI confident interval
  2. aEstimated hazard ratio after adjustments for age at enrollment (continuous), study (13 cohorts), smoking status (never, former, current smokers), and alcohol consumption (non-drinkers or current drinkers)
  3. bEstimated hazard ratio after adjustments for age at enrollment (continuous), study (13 cohorts), smoking status (never, former, current smokers), alcohol consumption (non-drinkers or current drinkers), age at menarche (≤ 10 y, 11–12 y, 13–14 y, 15–16 y, ≥ 17 y), nulliparity (yes, no), and age at first delivery (≤ 20 y, 21–25 y, 26–30 y, ≥ 31 y)
  4. cFollow-up period after 50 years of age
Back to article page

Breast Cancer Research

ISSN: 1465-542X

Contact us