Table 1

Demographic characteristics of study subjects.

Non-exposed
(n=99)
Exposed
(n=296)
P values
Age (years)38.2 ± 8.445.8 ± 10.5<0.0001
 20 – 2915  (15.2)24  (8.1)
 30 – 3948  (48.5)61 (20.6)
 40 – 4923  (23.2)92 (31.1)
 ≥5013  (13.1)119 (40.2)
Sex0.0570
 Male89 (89.9)242 (81.8)
 Female10 (10.1)54 (18.2)
BMI (kg/m2)0.0266
 < 2334 (34.3)134 (45.3)
 23 – 2527 (27.3)89 (30.1)
 ≥ 2538 (38.4)73 (24.6)
Alcohol drinking0.3324
 Non-drinker or social drinker25 (25.3)61 (20.6)
 Moderate or heavy drinker 74 (74.7)235 (79.4)
Smoking0.1960
 Non-smoker or ex-smoker43 (43.4)107 (36.1)
 Current smoker56 (56.6)189 (74.9)
Working period (years)<0.0001
 0–958 (58.6)100 (33.8)
 10–1924 (24.2)74 (25.0)
 20–2916 (16.2)63 (21.3)
 ≥301 (1.0)59 (19.9)
Job<0.0001
 Office work99 (100.0)0 (0.0)
 Automobile repair0 (0.0)82 (27.7)
 Printing0 (0.0)142 (48.0)
 Shoemaking0 (0.0)45 (15.2)
 Plating0 (0.0)27 (9.1)
  • Data are shown as mean±SD or number (%).

  • *Drinking alcohol more than once a week.

  • BMI, body mass index.