Table 1 Characteristics of study populations
Japanese living in Nagano, Japan | Japanese Brazilians living in São Paulo, Brazil | Non-Japanese Brazilians living in São Paulo, Brazil | Pfor difference | |
|---|---|---|---|---|
Number of participants | 185 | 44 | 134 | |
Mean age (±SE), yr | 62.8 (0.40) | 63.8 (0.82) | 63.6 (0.47) | 0.37 |
P a | 0.31 | Reference | 0.84 | |
Family history of breast cancer, n (%) | 17 (9.2) | 5 (11.4) | 14 (10.5) | 0.92 |
P a | 0.68 | Reference | 0.98 | |
History of benign breast disease, n (%) | 11 (6.0) | 4 (9.1) | 8 (6.0) | 0.46 |
P a | 0.65 | Reference | 0.62 | |
Mean age at first menarche (±SE), yr | 13.9 (0.12) | 13.2 (0.26) | 13.3 (0.15) | <0.01 |
P a | <0.01 | Reference | 0.75 | |
Mean age at menopause (±SE), yr | 50.0 (0.34) | 50.8 (0.69) | 48.2 (0.40) | <0.01 |
P a | 0.29 | Reference | <0.01 | |
Nulliparous, n (%) | 17 (9.2) | 5 (11.4) | 15 (11.2) | 0.55 |
P a | 0.58 | Reference | 0.81 | |
Number of births (more than four births), n (%)b | 6 (3.6) | 12 (30.8) | 57 (47.9) | <0.01 |
P a | <0.01 | Reference | <0.01 | |
Mean age at first birth (±SE), yrb | 26.2 (0.34) | 26.5 (0.72) | 23.6 (0.41) | <0.01 |
P a | 0.65 | Reference | <0.01 | |
Breast feeding (yes), n (%)b | 154 (93.3) | 35 (89.7) | 107 (89.9) | 0.72 |
P a | 0.27 | Reference | 0.61 | |
Mean height (±SE), cm | 152.9 (0.43) | 151.8 (0.89) | 157.1 (0.52) | <0.01 |
P a | 0.29 | Reference | <0.01 | |
Mean body mass index (±SE), kg/m2 | 23.4 (0.28) | 24.7 (0.57) | 27.0 (0.34) | <0.01 |
P a | 0.04 | Reference | <0.01 | |
Smoking (ever smoker), n (%) | 6 (3.3) | 7 (15.9) | 38 (28.4) | <0.01 |
P a | <0.01 | Reference | <0.01 | |
Alcohol drinking (drinker), n (%) | 67 (36.2) | 5 (11.4) | 25 (18.7) | <0.01 |
P a | <0.01 | Reference | 0.63 | |
Physical activity in past 5 years (yes), n (%) | 85 (46.5) | 19 (43.2) | 26 (19.4) | <0.01 |
P a | <0.01 | Reference | <0.01 |