3. Results
3.1. Demographic characteristics Although 886 was calculated as the sample size for this study,there were 752 (85%) participants which consisted of 497 individuals exposed to cold and 255 controls who worked in offices. Among the exposed group, 52.7% were male, 62.0% were 21-30 years old, 54.1% attained elementary education, 48.9% were married, 21.3% were smokers with a mean smoking duration of 8.45 (SD 6.63) years, 31.4% was drinkers (Table 1).