Risk Factors for Premenopausal Breast Cancer in Bangladesh
Table 1
Characteristics of breast cancer cases and matched controls.
Risk factors
Characteristics
Case ()
Control ()
Reproductive factors
Age at menarche, years, mean
11.5
12.0
0.0002
Age at first childbirth, years, mean
20.8
22.3
0.006
Parity, mean
2.2
2.1
0.69
Breastfeeding, months, mean
55.3
52.7
0.54
Anthropometric factors
Weight at the age of 18, kg, mean
42.8
44.8
0.009
Current weight, kg, mean
55.7
53.7
0.01
Weight gain since the age of 18, kg, mean
13.0
8.9
0.0001
Current height, cm, mean
154.1
155.4
0.09
BMI at the age of 18, kg/m2, mean
18.1
18.6
0.9
Current BMI (kg/m2)
0.0001
≤18.5
5 (4%)
4 (3%)
18.5–24.99
89 (69%)
116 (90%)
≥25
35 (27%)
9 (7%)
Socioeconomic factors
Water source
0.5
Tap
51 (39%)
58 (45%)
Tube well (untreated)
19 (15%)
14 (11%)
Tube well (treated)
59 (46%)
57 (44%)
Highest education
0.0001
None or ≤grade 10
115 (89%)
87 (67%)
≥grade 11
12 (9%)
40 (31%)
Income (Bangladeshi taka per month), mean
3,454
4,370
0.2
BMI, body mass index. Current weight (kg): for cases, current weight was weight at the time of breast cancer diagnosis; for controls, current weight was weight at the time of interview. For cases: mean weight gain (kg) from the age of 18 years to weight at breast cancer diagnosis; for controls: mean weight gain (kg) from the age of 18 years to weight at the date of interview. Current BMI (kg/m2): for cases, current BMI was BMI at the time of breast cancer diagnosis; for controls, current BMI was BMI at the time of interview.
