DIETARY AND LIFE-STYLE CORRELATES OF PASSIVE SMOKING IN HONG-KONG, JAPAN, SWEDEN, AND THE USA

From epidemiologic studies in several countries, passive smoking has b een associated with increased risk for lung cancer, respiratory diseas es, and coronary heart disease. Since the relative risks derived from those studies are weak, i.e. relative risk less than two, we investiga ted whether poorer diets and less healthy lifestyles might act as conf ounders and be correlated with having a smoking husband on a cross-cul tural basis. Characteristics of never-smoked wives with or without smo king husbands were compared between 530 women from Hong Kong, 13,047 f rom Japan, 87 from Sweden, and 144 from the U.S. In all four sites, wi ves with smoking husbands generally ate less healthy diets. They had a tendency to eat more fried food but less fruit than wives with nonsmo king husbands. Other healthy traits, e.g. avoiding obesity, dietary ch olesterol and alcohol; or Caking vitamins and participating in prevent ive screening were also less prevalent among wives with smoking husban ds. These patterns suggest that never-smoked wives with smoking husban ds tend to share the same less healthy dietary traits characteristic o f smokers, and to have dietary habits associated with increased risk f or lung cancer and heart disease in their societies. These results emp hasize the need to take into account the potential confounding effects of diet and lifestyle in studies evaluating the health effects of pas sive smoking, especially since it is known that the current prevalence rates of smoking among men is indirectly associated with social class and education in affluent urban societies. (C) 1997 Elsevier Science Ltd.