Skip to main content

Table 2 Adjusted ORs for breast cancer associated with hormone-related risk factors by ER/PR status

From: Hormone-related risk factors for breast cancer in women under age 50 years by estrogen and progesterone receptor status: results from a case–control and a case–case comparison

Variables

No. controls

All cases versus controls

ER+PR+ cases versus controls

ER- PR- cases versus controls

ER+PR+ cases versus ER- PR- cases

  

Number of cases

OR (95% CI)

Number of cases

OR (95% CI)

Number of cases

OR (95% CI)

OR (95% CI)

Age at menarche, years

   ≤ 11

90

400

1.00

188

1.00

92

1.00

1.00

   12

109

532

1.13 (0.83–1.55)

278

1.24 (0.88–1.75)

119

1.18 (0.79–1.77)

1.04 (0.74–1.47)

   13

121

475

0.88 (0.65–1.21)

231

0.87 (0.62–1.24)

110

0.94 (0.62–1.41)

0.93 (0.65–1.33)

   ≥ 14

120

318

0.61 (0.44–0.85)

157

0.60 (0.42–0.86)

64

0.59 (0.38–0.92)

1.02 (0.67–1.53)

   Trend p value

  

0.0007

 

0.0006

 

0.008

0.85

Number of full-term pregnanciesa

   None

125

564

1.00

301

1.00

113

1.00

1.00

   1

85

347

0.91 (0.66–1.25)

157

0.77 (0.55–1.10)

82

1.06 (0.70–1.62)

0.70 (0.49–1.02)

   2

139

492

0.81 (0.61–1.07)

251

0.77 (0.57–1.06)

106

0.95 (0.64–1.39)

0.84 (0.60–1.18)

   3

56

224

0.81 (0.56–1.18)

100

0.69 (0.45–1.04)

54

1.06 (0.65–1.73)

0.68 (0.44–1.05)

   ≥ 4

35

98

0.49 (0.31–0.78)

45

0.47 (0.28–0.80)

30

0.72 (0.39–1.33)

0.65 (0.37–1.15)

   Trend p value

  

0.008

 

0.005

 

0.50

0.09

Age at first full-term pregnancy for parous women, yearsa,b

   <22

68

316

1.00

126

1.00

96

1.00

1.00

   22–27

89

333

1.07 (0.72–1.58)

149

1.14 (0.73–1.78)

81

0.92 (0.56–1.50)

1.25 (0.81–1.94)

   28–31

78

265

1.03 (0.66–1.60)

134

1.17 (0.71–1.93)

57

0.82 (0.46–1.45)

1.42 (0.85–2.37)

   ≥ 32

80

247

0.92 (0.57–1.48)

144

1.23 (0.72–2.10)

38

0.56 (0.30–1.07)

2.22 (1.24–3.98)

   Trend p value

  

0.65

 

0.49

 

0.08

0.009

Duration of breastfeeding for parous women, monthsa,b

   0

38

247

1.00

102

1.00

63

1.00

1.00

   <1

23

144

0.99 (0.56–1.77)

65

1.01 (0.53–1.90)

38

1.19 (0.59–2.39)

0.82 (0.47–1.44)

   1–6

80

273

0.58 (0.37–0.91)

131

0.57 (0.34–0.94)

68

0.72 (0.41–1.27)

0.77 (0.47–1.26)

   7–23

110

322

0.52 (0.33–0.82)

165

0.52 (0.31–0.87)

63

0.55 (0.31–0.98)

0.97 (0.59–1.61)

   ≥ 24

64

175

0.51 (0.30–0.86)

90

0.49 (0.27–0.87)

40

0.62 (0.32–1.21)

0.77 (0.42–1.39)

   Trend p value

  

0.001

 

0.002

 

0.03

0.63

BMI 1 year before reference date, kg/m2

   <25

257

939

1.00

495

1.00

183

1.00

1.00

   25–29

95

425

1.18 (0.89–1.55)

209

1.11 (0.82–1.50)

101

1.41 (0.99–2.02)

0.81 (0.59–1.10)

   30–34

51

221

1.01 (0.70–1.44)

94

0.88 (0.59–1.30)

61

1.43 (0.91–2.23)

0.60 (0.40–0.89)

   ≥ 35

37

140

0.88 (0.58–1.34)

56

0.69 (0.43–1.11)

40

1.18 (0.70–2.01)

0.61 (0.38–0.99)

   Trend p value

  

0.82

 

0.20

 

0.16

0.005

Duration of COC use, years

   Never

47

244

1.00

128

1.00

47

1.00

1.00

   <1

73

295

0.78 (0.51–1.18)

133

0.70 (0.44–1.12)

59

0.76 (0.43–1.33)

0.93 (0.57–1.52)

   1–4

108

429

0.80 (0.54–1.19)

227

0.81 (0.53–1.25)

90

0.87 (0.52–1.46)

0.92 (0.59–1.43)

   5–9

115

362

0.62 (0.42–0.93)

173

0.57 (0.37–0.88)

90

0.82 (0.49–1.37)

0.71 (0.45–1.12)

   ≥ 10

97

395

0.84 (0.56–1.26)

193

0.76 (0.49–1.18)

99

1.27 (0.75–2.14)

0.61 (0.39–0.96)

   Trend p value

  

0.30

 

0.16

 

0.18

0.008

Alcohol drinking status during reference agec

   Never

141

558

1.00

251

1.00

138

1.00

1.00

   Former

90

328

0.96 (0.71–1.31)

162

1.02 (0.72–1.44)

74

0.88 (0.59–1.33)

1.14 (0.79–1.64)

   Current

209

839

1.05 (0.81–1.36)

441

1.17 (0.88–1.55)

173

0.93 (0.67–1.30)

1.25 (0.93–1.68)

Average number of alcoholic drinks per week in recent 5 years

   Never

141

558

1.00

251

1.00

138

1.00

1.00

   <3

130

481

1.01 (0.76–1.35)

248

1.11 (0.81–1.53)

101

0.89 (0.61–1.30)

1.22 (0.87–1.71)

   3–5

49

171

0.93 (0.63–1.37)

90

1.01 (0.66–1.54)

34

0.76 (0.45–1.28)

1.31 (0.81–2.11)

   6–11

32

157

1.16 (0.75–1.81)

82

1.26 (0.78–2.03)

34

1.06 (0.60–1.86)

1.20 (0.74–1.94)

   > 12

17

127

1.77 (1.01–3.08)

68

2.10 (1.17–3.79)

27

1.71 (0.87–3.38)

1.24 (0.73–2.09)

   Trend p value

  

0.12

 

0.03

 

0.42

0.23

Drinking alcohol but not in the recent five years

71

231

0.88 (0.63–1.22)

115

0.92 (0.63–1.34)

51

0.80 (0.51–1.26)

1.14 (0.76–1.73)

  1. ORs are from multivariable unconditional logistic regression models with the adjustment for race, age, education, first-degree breast cancer family history, age at menarche, gravidity, number of full-term pregnancies, BMI 1 year before reference date, COC use, the average number of alcoholic drinks per week in the recent 5 years, a variable combining menopausal status and hormone therapy use except where otherwise noted. BMI, body mass index; COC, combined oral contraceptive; CI, confidence interval; ER, estrogen receptor; OR, odds ratio; PR, progesterone receptor. aModels did not include gravidity. bAge at first full-term pregnancy and duration of breastfeeding mutually adjusted for each other. cAlcohol drinking status during reference age replaced the number of alcoholic drinks per week in the recent 5 years in the models.
Back to article page

Breast Cancer Research

ISSN: 1465-542X

Contact us