Introduction
Materials and methods
General method
Study population
Recruitment
Subject selection
Definitions of ethnicity
White Caucasian
Recent Chinese migrant
Early Chinese migrant
Western born Chinese
Data collection
Epidemiological data
Anthropometric measures
Dietary acculturation
Statistical methods
Results
Characteristics of subjects
Mean (SD) | |||||||
---|---|---|---|---|---|---|---|
Chinese born in the West or migrated to the West before 21 | Recent Chinese migrants |
P
| |||||
Caucasians |
P
b
|
P
c
|
P
d
|
P
e
| |||
(N = 413) | (N = 216) | (N = 421) | |||||
Age (years) | 61.5 (6.9) | 58.5 (6.7) | 60.3 (6.4) | <0.001 | <0.001 | 0.03 | 0.004 |
Years lived in Western countries (years) | 61.3 (6.9) | 46.2 (12.7) | 6.7 (2.9) | <0.001 | <0.001 | <0.001 | <0.001 |
Education (% yes) | |||||||
Less than 8 years | 1.0 | 3.3 | 15.0 | ||||
8 to 11 years | 9.7 | 10.7 | 16.9 | ||||
High School | 20.9 | 24.2 | 22.8 | <0.001 | 0.04 | <0.001 | <0.001 |
Vocational/Technical School | 7.5 | 10.2 | 9.0 | ||||
College | 31.1 | 20.9 | 19.0 | ||||
Bachelor's Degree or higher | 29.7 | 30.7 | 17.3 |
Reproductive risk factors
Adjusted Mean (Lower and Upper 95% Confidence Limits) | |||||||
---|---|---|---|---|---|---|---|
P
| |||||||
Caucasians | Chinese born in the West or migrated to the West before 21 | Recent Chinese migrants |
P
b
|
P
c
|
P
d
|
P
e
| |
(N = 413) | (N = 216) | (N = 421) | |||||
Age at menarche (years)f, g | 12.8 (12.6, 13.0) | 13.0 (12.7, 13.2) | 13.7 (13.6, 13.9) | 0.01 | 0.64 | <0.001 | <0.001 |
Age at first live birth (years)f, h | 24.3 (23.8, 24.7) | 24.9 (24.3, 25.5) | 25.5 (25.1, 25.9) | 0.002 | 0.34 | <0.001 | 0.22 |
Number of live births (%) | |||||||
0 | 14.5 (11.3, 18.5) | 8.5 (5.2, 13.8) | 4.5 (2.8, 7.2) | 0.60 | 0.14 | <0.001 | 0.19 |
1 | 9.9 (7.3, 13.2) | 7.7 (4.6, 12.7) | 18.0 (14.3, 22.4) | 0.08 | 0.99 | 0.005 | 0.007 |
2 | 36.9 (32.3, 41.8) | 40.1 (33.2, 47.4) | 43.3 (38.5, 48.2) | 0.14 | 0.99 | 0.22 | 0.99 |
3 | 21.6 (17.7, 26.1) | 30.8 (24.7, 37.7) | 19.6 (15.9, 37.7) | 0.08 | 0.05 | 0.99 | 0.008 |
≥ 4 | 11.9 (8.9, 15.9) | 5.3 (2.9, 9.6) | 8.0 (5.7, 11.2) | 0.33 | 0.05 | 0.24 | 0.71 |
Breastfeeding (% yes) | 76.6 (71.6, 80.9) | 63.4 (55.9, 70.2) | 72.1 (66.9, 76.8) | <0.001 | 0.62 | <0.001 | 0.14 |
Age at natural menopause (years)f, i | 50.1 (49.7, 50.6) | 50.6 (50.0, 51.3) | 49.9 (49.5, 50.3) | 0.79 | 0.53 | 0.99 | 0.10 |
Age at surgical menopause with both ovaries removed (years)f, j | 44.0 (41.2, 46.9) | 45.0 (41.3, 48.9) | 45.0 (42.2, 48.0) | 0.68 | 0.99 | 0.99 | 0.99 |
Ever used oral contraceptives (% yes) | 85.8 (81.4, 89.3) | 73.9 (67.3, 79.6) | 40.7 (35.9, 45.7) | <0.001 | 0.002 | <0.001 | <0.001 |
Duration of oral contraceptive use (years)f, k | 3.6 (3.0, 4.3) | 2.5 (2.0, 3.2) | 2.1 (1.7, 2.6) | 0.14 | 0.03 | <0.001 | 0.81 |
Ever used hormone replacement therapy (% yes) | 47.4 (41.7, 53.1) | 33.1 (26.6, 40.3) | 28.1 (23.9, 32.6) | 0.03 | 0.003 | <0.001 | 0.65 |
Duration of hormone replacement therapy use (years)f, l | 2.1 (1.6, 2.8) | 1.7 (1.2, 2.6) | 1.1 (0.8, 1.4) | 0.01 | 0.99 | 0.001 | 0.17 |
Anthropometric risk factors
Adjusted Mean (Lower and Upper 95% Confidence Limits) | |||||||
---|---|---|---|---|---|---|---|
P
| |||||||
Caucasians | Chinese born in the West or migrated to the West before 21 | Recent Chinese migrants |
P
b
|
P
c
|
P
d
|
P
e
| |
(N = 382) | (N = 53) | (N = 357) | |||||
Standing height (cm) | 162.1 (161.4, 162.8) | 156.3 (154.6, 157.9) | 155.8 (155.3, 156.4) | 0.03 | <0.001 | <0.001 | 0.99 |
Weight (kg) | 69.5 (68.1, 70.9) | 57.7 (54.8, 60.8) | 55.2 (54.2, 56.3) | <0.001 | <0.001 | <0.001 | 0.35 |
BMI (kg/m2) | 26.4 (25.9, 26.9) | 23.6 (22.5, 24.8) | 22.7 (22.4, 23.1) | <0.001 | <0.001 | <0.001 | 0.40 |
Sitting height (cm) | 85.0 (84.6, 85.4) | 83.5 (82.6, 84.5) | 83.3 (83.0, 83.7) | 0.06 | 0.01 | <0.001 | 0.99 |
Leg length (cm) | 77.1 (76.6, 77.6) | 72.7 (71.5, 73.9) | 72.0 (72.0, 72.9) | 0.14 | <0.001 | <0.001 | 0.99 |
Waist circumference (cm) | 84.6 (83.3, 85.8) | 77.4 (74.6, 80.4) | 76.6 (75.6, 77.6) | <0.001 | <0.001 | <0.001 | 0.99 |
Hip circumference (cm) | 104.5 (103.4, 105.6) | 94.5 (92.1, 97.0) | 93.4 (92.6, 94.3) | <0.001 | <0.001 | <0.001 | 0.99 |
Subscapular skinfold (mm) | 30.0 (28.8, 31.3) | 30.9 (27.8, 34.5) | 27.3 (26.3, 28.4) | 0.65 | 0.99 | 0.002 | 0.10 |
Suprailiac skinfold (mm) | 30.9 (29.3, 32.5) | 30.8 (27.0, 35.2) | 27.7 (26.4, 29.0) | <0.001 | 0.99 | 0.003 | 0.38 |
Triceps skinfold (mm) | 33.4 (32.3, 34.5) | 32.9 (30.2, 35.8) | 29.4 (28.5, 30.3) | 0.04 | 0.99 | <0.001 | 0.05 |
Other risk factors
Adjusted Mean (Lower and Upper 95% Confidence Limits) (% Yes) | |||||||
---|---|---|---|---|---|---|---|
P
| |||||||
Caucasians | Chinese born in the West or migrated to the West before 21 | Recent Chinese migrants |
P
b
|
P
c
|
P
d
|
P
e
| |
(N = 413) | (N = 216) | (N = 421) | |||||
First degree relatives with breast cancer
f
| 16.0 (12.0, 21.1) | 14.7 (10.0, 21.0) | 7.8 (5.5, 11.0) | 0.87 | 0.99 | 0.003 | 0.04 |
Any benign breast biopsy | 14.8 (11.5, 18.9) | 8.7 (5.5, 8.2) | 5.4 (3.5, 8.2) | 0.04 | 0.10 | <0.001 | 0.39 |
Consumption of alcohol at least once per week for six months or longer | 60.6 (53.5, 67.2) | 9.4 (6.0, 14.4) | 2.3 (1.2, 4.2) | <0.001 | <0.001 | <0.001 | <0.001 |
Consumption of alcohol at least once per week currently | 50.9 (45.7, 56.0) | 8.7 (5.6, 13.4) | 1.4 (0.6, 3.3) | <0.001 | <0.001 | <0.001 | <0.001 |
Smoked at least one cigarette per day for three months or longer | 46.5 (39.1, 54.1) | 12.4 (8.2, 18.2) | 1.7 (0.8, 3.6) | <0.001 | <0.001 | <0.001 | <0.001 |
Smoking at least one cigarette per day | 11.0 (8.2, 14.6) | 3.3 (1.5, 6.7) | 0.5 (0.1, 1.9) | 0.01 | 0.006 | <0.001 | 0.05 |
Currently | |||||||
Any X-ray examinations that included the chest areag | 73.7 (67.4, 79.1) | 78.5 (71.1, 84.4) | 97.4 (95.3, 98.5) | 0.20 | 0.69 | <0.001 | <0.001 |
Any X-ray examination for tuberculosisg | 58.3 (51.6, 64.7) | 71.9 (64.3, 78.4) | 96.4 (94.2, 97.9) | 0.09 | 0.008 | <0.001 | <0.001 |
Dietary acculturation
Caucasians | Chinese born in the West or migrated to the West before 21 | Recent Chinese migrants |
P
a
| ||||
---|---|---|---|---|---|---|---|
P
b
|
P
c
|
P
d
|
P
e
| ||||
(N = 379) | (N = 152) | (N = 374) | |||||
Chinese dietary practices (% yes) | |||||||
Eat tofu | 20.8 | 89.5 | 95.7 | ||||
Eat traditionally preserved/pickled vegetables | 40.1 | 49.3 | 56.7 | ||||
Balance yin/yang foods | 7.1 | 23.7 | 33.2 | ||||
Avoid cold foods and drinks | 11.9 | 29.0 | 44.7 | ||||
Eat a Chinese style breakfast (for example,. congee) | 5.0 | 46.1 | 65.5 | ||||
Chinese Dietary Acculturation Scoref | 0.09 (0.08, 0.12) | 0.42 (0.37, 0.47) | 0.56 (0.53, 0.60) | <0.001 | <0.001 | <0.001 | <0.001 |
[Adjusted Mean (95% Confidence Limits)] | |||||||
Western dietary practices (% yes) | |||||||
Eat bread, rolls, or bagels | 96.6 | 94.1 | 94.9 | ||||
Drink carbonated beverages | 63.9 | 50.0 | 27.0 | ||||
Eat ground beef or hamburgers | 77.6 | 59.9 | 30.5 | ||||
Eat pizza or spaghetti with tomato sauce | 89.2 | 79.6 | 52.7 | ||||
Eat any kind of cheese | 97.1 | 80.3 | 49.7 | ||||
Drink milk or eat milk products | 94.5 | 87.5 | 89.6 | ||||
Eat cakes, pies, or cookies for dessert | 92.7 | 94.7 | 80.0 | ||||
Eat packaged or prepared foods (for example, TV dinners) | 42.5 | 50.0 | 40.1 | ||||
Eat at Western fast food restaurants | 40.9 | 50.0 | 33.2 | ||||
Eat between meals | 81.3 | 90.1 | 80.9 | ||||
Western Dietary Acculturation Scoreg | 0.80 (0.78, 0.81) | 0.77 (0.74, 0.79) | 0.64 (0.61, 0.66) | <0.001 | 0.10 | <0.001 | <0.001 |
[Adjusted Mean (95% Confidence Limits)] |
Recent Chinese migrants by place of origin
Adjusted Mean (Lower and Upper 95% Confidence Limits) | |||||||
---|---|---|---|---|---|---|---|
From | Had lived in both | From |
P
| ||||
Mainland | Mainland China | Hong Kong |
P
b
|
P
c
|
P
d
|
P
e
| |
China | and Hong Kong | ||||||
(N = 147) | (N = 141) | (N = 133) | |||||
Age at menarche (years)f, g | 14.3 (14.1, 14.6) | 13.7 (13.4, 13.9) | 13.0 (12.7, 13.3) | <0.001 | 0.004 | <0.001 | 0.003 |
Age at first live birth (years)f, h | 24.6 (24.0, 25.2) | 25.7 (25.0, 26.3) | 26.3 (25.6, 27.0) | 0.003 | 0.07 | 0.003 | 0.47 |
Parity (% yes) | 99.0 (95.5, 99.8) | 97.4 (93.1, 99.0) | 94.4 (87.9, 97.5) | 0.06 | 0.86 | 0.12 | 0.53 |
Breastfeeding (% yes) | 95.4 (89.9, 98.0) | 66.7 (56.9, 75.1) | 45.1 (34.1, 56.7) | <0.001 | <0.001 | <0.001 | 0.007 |
Ever used oral contraceptives (% yes) | 29.5 (21.7, 38.8) | 41.4 (32.8, 50.5) | 49.6 (39.9, 59.4) | 0.02 | 0.21 | 0.02 | 0.64 |
Ever used hormone therapy (% yes)i | 12.8 (8.0, 19.7) | 37.8 (30.0, 46.9) | 35.6 (26.8, 45.4) | <0.001 | <0.001 | <0.001 | 0.99 |
Standing height (cm)j | 156.5 (155.4, 157.5) | 156.6 (155.6, 157.5) | 154.5 (153.5, 155.6) | 0.009 | 0.99 | 0.05 | 0.01 |
Weight (kg)j | 55.9 (54.3, 57.6) | 55.5 (54.0, 56.9) | 53.8 (52.3, 55.4) | 0.15 | 0.99 | 0.22 | 0.34 |
BMI (kg/m2)j | 22.9 (22.3, 23.5) | 22.6 (22.1, 23.2) | 22.5 (22.0, 23.1) | 0.77 | 0.99 | 0.99 | 0.99 |
First degree history of breast cancer (% yes)k | 4.4 (1.9, 9.7) | 5.1 (2.3, 10.8) | 14.3 (8.3, 23.4) | 0.02 | 0.99 | 0.06 | 0.07 |
Any benign breast biopsy (% yes) | 2.9 (1.2, 7.0) | 4.4 (1.9, 9.6) | 7.8 (3.9, 14.9) | 0.21 | 0.99 | 0.26 | 0.81 |
Chinese Dietary Acculturation Scorel, m | 0.64 (0.59, 0.68) | 0.58 (0.54, 0.63) | 0.50 (0.46, 0.54) | <0.001 | 0.34 | <0.001 | 0.006 |
Western Dietary Acculturation Scorem, n | 0.62 (0.58, 0.66) | 0.65 (0.61, 0.68) | 0.65 (0.62, 0.68) | 0.50 | 0.99 | 0.78 | 0.99 |
Selected breast cancer risk factors in recent Chinese migrants and postmenopausal Chinese women living in urban China
Mean (SD) | Mean (SD) | |||||
---|---|---|---|---|---|---|
Recent Chinese Migrants | Postmenopausal | Recent Chinese Migrants | Postmenopausal | |||
From Mainland China | Chinese Women |
P
a
| From Hong Kong | Chinese Women |
P
a
| |
in This Study | Living in Shanghaib | in This Study | Living in Hong Kong | |||
High school or higher (% yes) | 74.2 | 64.0 | 0.12 | 74.4 | NAc | NA |
Age at menarche (years) | 14.6 (1.8) | 15.0 (2.0) | 0.03 | 12.8 (1.9) | 15.1 (2.3)d | <0.001 |
Age at first live birth (years) | 25.2 (3.6) | 24.0 (4.0) | 0.001 | 26.9 (3.9) | NAc | NA |
Number of live births | 2.2 (1.1) | 2.3 (1.0) | 0.30 | 2.1 (1.4) | 2.0 (2.0)e | 0.59 |
Age at natural menopause (years) | 50.0 (3.4) | 48.0 (5.0) | <0.001 | 50.0 (3.2) | 49.4 (3.4)c | 0.08 |
BMI (kg/m2) | 23.2 (3.0) | 24.2 (3.6) | 0.002 | 22.6 (3.2) | 22.2 (3.8)e to 23.6 (3.4)d | 0.58f |