Table 1.
Baseline characteristics of the Shanghai Women's (1997–2000) and Men's (2002–2006) Health Studies: Liver cancer cases compared with other cohort members
| Women | Men | |||||
|---|---|---|---|---|---|---|
| Non‐cases (n = 72 368) | Cases (n = 118) | P‐value | Non‐cases (n = 60 202) | Cases (n = 149) | P‐value | |
| Age at enrolment (years, mean ± SD) | 52.4 ± 9.0 | 59.0 ± 8.8 | <0.01 | 55.2 ± 9.7 | 59.4 ± 10.1 | <0.01 |
| BMI (kg/m2, mean ± SE) | 24.0 ± 0.0 | 24.7 ± 0.3 | 0.03 | 23.7 ± 0.0 | 23.3 ± 0.3 | 0.10 |
| Total energy intake (kcal/day, mean ± SE) | 1644.1 ± 1.3 | 1688.5 ± 32.1 | 0.17 | 1908.3 ± 1.9 | 1910.0 ± 38.7 | 0.97 |
| Family income level, per person per year (%) | ||||||
| Low | 27.5 | 29.2 | 0.62 | 54.9 | 68.0 | <0.01 |
| Middle | 38.9 | 44.9 | 35.4 | 24.8 | ||
| High | 33.6 | 25.8 | 9.8 | 7.2 | ||
| Education level (%) | ||||||
| Elementary school or less | 21.1 | 29.4 | <0.01 | 7.8 | 9.5 | 0.01 |
| Middle school | 37.3 | 29.2 | 33.0 | 31.9 | ||
| High school | 28.0 | 32.9 | 35.7 | 43.9 | ||
| College or above | 13.5 | 8.5 | 23.4 | 14.7 | ||
| Ever had chronic viral hepatitis (%) | 2.6 | 27.1 | <0.01 | 6.8 | 40.3 | <0.01 |
| Ever had chronic liver disease or cirrhosis (%) | 0.8 | 3.2 | <0.01 | 3.3 | 16.6 | <0.01 |
| Ever had diabetes (%) | 4.2 | 6.2 | 0.16 | 6.1 | 8.7 | 0.01 |
| Ever had cholelithiasis or cholecystectomy (%) | 11.3 | 17.0 | 0.01 | 7.7 | 13.7 | <0.01 |
| Family history of liver cancer in first‐degree relatives (%) | 3.3 | 12.7 | <0.01 | 3.5 | 11.7 | <0.01 |
| Ever smoker (%) | 2.8 | 3.5 | 0.34 | 69.6 | 70.0 | 0.69 |
| Ever drank alcohol (%) | 2.3 | 1.9 | 0.98 | 33.6 | 25.9 | 0.72 |
| Regular physical activity during past 5 years (%) | 35.0 | 35.4 | 0.34 | 35.4 | 35.7 | 0.92 |
| Vitamin C supplement use (%) | 7.0 | 6.4 | 0.65 | 5.5 | 16.6 | <0.01 |
| Vitamin E supplement use (%) | 10.9 | 7.0 | 0.06 | 4.5 | 6.1 | 0.66 |
| Multivitamin supplement use (%) | 7.1 | 7.0 | 0.56 | 7.5 | 13.6 | 0.01 |
All variables were standardized to age distribution at baseline survey. The general linear model for continuous variables and Cochran–Mantel–Haenszel statistics for categorical variables were used. BMI, body mass index; SD, standard deviation; SE, standard error.