Table 1.

Characteristics of cases and controls

Controls (n = 420)Cases (n = 142)P
Matched variables*
    Age (y)58 (29-87)58 (29-86)0.66
    Postmenopausal, no. (%)277 (65.5%)94 (65.7%)0.84
Unmatched variables
    Body weight (kg)69.2 ± 13.169.1 ± 14.20.97
    Body mass index (kg/m2)24.9 ± 4.524.9 ± 5.20.85
    Daily calcium intake (mg)1,161 ± 4701,117 ± 3960.33
    Current smoking, N (%)79 (20.3%)32 (23.2%)0.47
    Units of alcohol per week, no. of subjects (%)0.25
        <195 (22.3%)37 (26.1%)
        1-7200 (46.9%)55 (38.7%)
        8-1486 (20.2%)37 (26.1%)
        >1445 (10.6%)13 (9.2%)
Pieces of fresh fruit per week, no. of subjects (%)0.62
        ≤7177 (41.5%)65 (45.5%)
        8-14149 (34.9%)44 (30.8%)
        ≥15101 (23.7%)34 (23.8%)
    Age at menarche, range (y)13.5 (10-18)13.5 (10-19)0.94
    Nulliparas, no. (%)44 (10.6%)13 (9.3%)0.66
    No. of childbirths (range)2.3 (1-10)2.3 (1-6)0.99
    Age at first childbirth, range (y)24.9 (15-40)24.8 (16-38)0.74
    Age at last menstrual bleeding, range (y)§49.4 (28-65)50.5 (40-60)0.07
    Ever use of postmenopausal HRT, no. (%)§156 (58.4%)49 (54.4%)0.78
    A family history of breast cancer, no. (%)126 (30.1%)18 (12.8%)<0.01
  • *In addition, cases and controls were matched on time of year of blood sampling.

  • Mean with range.

  • Excluding nulliparas.

  • §Only postmenopausal women.