not be expected to be significant for the nonsmokers analyzed separately.
Hirayama’s (1984) study, based on a cohort of 91,450 nonsmoking Japanese women, suggested an increased mortality from brain tumors among women whose husbands smoked. The rate ratios were 3.0, 6.3, and 4.3 for exposure to husbands smoking 1–14, 15–19, or 20 or more cigarettes per day, as compared with nonsmoking wives of nonsmoking husbands as the reference group. A trend was noted for all cancer sites, but the risk elevation became insignificant when lung, nasal sinus, brain, and breast cancers were excluded. No significant associations were found for cancers of the stomach, colon, rectum, liver, peritoneum, ovary, skin, or bone, or for malignant lymphoma or leukemia.
Sandler et al. (1985a,b,c), reporting on a case-control study from North Carolina, suggested an association of exposure to ETS at different periods during a lifetime with various types of cancer. People with cancer at any site, except basal cell cancer of the skin, were included in this study. The cases were drawn from a hospital-based tumor registry, irrespective of personal histories of smoking. Mailed questionnaires were used for collecting data on exposure, preceded by a telephone call for the control subjects, but not for the cases.
Many of the odds ratios reported in these articles are for the combined group, as briefly reported in Table 13–1. However, some results were reported separately for nonsmoking cases (No.=231) and controls (No.=235). The results discussed below are based on the latter group and thus reflect only 31% of the total eligible patient group.
The overall crude cancer risk among individuals who were ever married to smokers was 2.1 times that of those never married to smokers. Significantly elevated risks (p<0.05) were seen also for cancer of the cervix (odds ratio 2.1) and endocrine glands (odds ratio 4.4) (Sandler et al., 1985a). A nonsignificant odds ratio of 2.0 was obtained for cancer of the breast.
A subset of this study involved subjects who had lived with both natural parents for most of the first 10 years of life and had information on the smoking habits of both parents and spouses.