Epidemiologic risk factors for breast cancer related to menopausal status in Indonesia

To clarify the risk factors of breast cancer in premenopausal and postmenopausal women, a hospital-based case-control study was conducted in Indonesia. Three hundred incident cases were interviewed and 600 controls were selected, matching for age and socio-economic class. Cases and controls were divided according to their menopausal status and analyzed separately. Following significant findings were revealed. For premenopausal breast cancer, an increased risk was detected in women with breast trauma (adjusted RR: 2.62; 95% Cl: 1.09-6.31), oral contraceptive use (4.96; 1.51-16.24), milk consumption (1.81; 1.01-3.35, daily intake vs no intake), fresh fruits intake (2.42; 1.16-5.05, 3-4 timex/week vs less than once/week intake). A decreased risk was detected in women with cooked-vegetable intake (0.34; 0.15-0.77, daily intake vs not daily intake). For postmenopausal breast cancer an increased risk was found,in women having menarche at the age of 15 years or over (2.25; 1.35-3.76), regular menstruation after thirty years old (4.61;2.45-8.67),milk consumption (5.84; 2.92-11.66, daily intake vs no intake), and a decreased risk in women who were divorced or widowed (0.33;0.18-0.58), and whose number of live birth or breast-fed children was high (0.32; 0.13-0.76, six or more breast-fed children vs no breast-fed child).