Table 1

Comparison of cases and controls by selected demographic and risk factors among postmenopausal Iowa women

Subjects who completed surveySubjects who provided a blood sample
Cases (n = 273)Controls (n = 657)OR (95% CI)Cases (n = 156)Controls (n = 332)OR (95% CI)
Age, ≥64 yr921891.26 (0.93–1.70)46831.26 (0.82–1.92)
High school education or higher1282771.21 (0.91–1.61)811531.26 (0.86–1.85)
First-degree relatives with breast cancer47681.80 (1.21–2.69)26381.55 (0.90–2.66)
Ever used estrogen1252511.37 (1.03–1.83)661430.97 (0.66–1.21)
Waist:hip ratio of ≥0.772114981.09 (0.78–1.52)1162620.78 (0.50–1.42)
Menarche at ≤12 yr1062780.87 (0.65–1.16)611490.79 (0.54–1.16)
Menopause at ≥52 yr872160.96 (0.71–1.29)471060.92 (0.61–1.39)
First live birth at ≥25 yr701760.94 (0.68–1.30)45881.12 (0.74–1.72)
Consumed ≥2.6 g of alcohol per day701661.02 (0.74–1.41)40841.02 (0.66–1.58)
Ever smoker901981.14 (0.84–1.54)51981.17 (0.78–1.76)
 Quit >10 yr ago40721.40 (0.92–2.13)24321.67 (0.94–2.98)
 1–14 cigarettes/day or smoked <25 yr14400.88 (0.47–1.66)9151.34 (0.57–3.15)
 15 cigarettes/day and smoked >25 yr36851.07 (0.70–1.63)18510.79 (0.44–1.41)
Red meat intake
 2nd highest vs. lowest tertile832171.01 (0.70–1.44)501110.97 (0.60–1.59)
 Highest vs. lowest tertile1082241.27 (0.90–1.79)621261.06 (0.67–1.70)
Consistently ate meats well done801431.53 (1.10–2.12)44751.36 (0.88–2.12)