PASSIVE SMOKING AT WORK AS A RISK FACTOR FOR CORONARY HEART-DISEASE IN CHINESE WOMEN WHO HAVE NEVER SMOKED

Objective-To study whether passive smoking at work is a risk factor fo r coronary heart disease. Design-Case-control study. Setting-Xi'an, Ch ina. Subject-59 patients with coronary heart disease and 126 controls, all Chinese women with full time jobs, who had never smoked cigarette s. Results-The crude odds ratio for passive smoking from husband was 2 .12 (95% confidence interval 1.06 to 4.25) and at work was 2.45 (1.23 to 4.88). The final logistic regression model, with passive smoking fr om husband and at work as the base, included age, history of hypertens ion, type A personality, and total cholesterol and high density lipopr otein cholesterol concentrations; the adjusted odds ratios for passive smoking from husband and at work were 1.24 (0.56 to 2.72) and 1.85 (0 .86 to 4.00) respectively. For passive smoking at work, statistically significant linear trends of increasing risks (for both crude and adju sted odds ratios) with increasing exposures (amount exposed daily, num ber of smokers, number of hours exposed daily, and cumulative exposure ) were observed. When these exposure variables were analysed as contin uous variables, the crude and adjusted odds ratios were also significa nt. Conclusion-Passive smoking at work is a risk factor for coronary h eart disease. Urgent public health measures are needed to reduce smoki ng and to protect non-smokers from passive smoking in China.