Anna Kalandidi

Passive smoking and diet in the etiology of lung cancer among non-smokets

A case-control study was undertaken in Athens to explore the role of passive smoking and diet in the causation of lung cancer, by histologic type, in non-smoking women. Among 160 women with lung cancer admitted to one of seven major hospitats in Greater Athens between 1987 and 1989, 154 were interviewed in person; of those interviewed, 91 were life-long non-smokers. Among 160 identified controls with fractures or other orthopedic conditions, 145 were interviewed in person; of those interviewed, 120 were life-long non-smokers. Marriage of a non-smoking woman to a smoket was associated with a relative risk for lung cancer of 2.1 (95% confidence interval [CI] 1.1–4.1); number of cigarettes smoked daily by the husband and years of exposure to husbands smoking were positively, but not significantly, related to lung cancer risk. There was no evidence of any association with exposure to smoking of other household members, and the association with exposure to passive smoking at work was small and not statistically significant. Dietary data collected through a semi-quantitative food-frequency questionnaire indicated that high consumption of fruits was inversely related to the risk of lung cancer (the relative risk between extreme quartiles was 0.27 (CI 0.10–0.74)). Neither vegetables nor any other food group had an additional protective effect; futthermore, the apparent protective effect of vegetables was not due to carotenoid vitamin A content and was only partly explained in terms of vitamin C. The associations of lung cancer risk with passive smoking and reduced fruit intake were independent and did not confound each other. Passive smoking was associated with an increase of the risk of all histologic types of cancer, although the elevation was more modest for adenocarcinoma.

A Case-Control Study of Endometrial Cancer in Relation to Reproductive, Somatometric, and Life-Style Variables

A hospital-based case-control study of cancer of the endometrium was conducted in Athens, Greece, from 1992 to 1994. The cases were 145 women residents of Greater Athens with histologically confirmed incident cancer of the endometrium, operated in the two cancer hospitals of the Greater Athens area or the major University Department of Obstetrics and Gynecology. Controls were 298 women residents of Greater Athens hospitalized for bone fractures or other orthopedic conditions in the accident hospital of Greater Athens. The data were analyzed by modeling through multiple logistic regression. The risk of endometrial cancer decreased with the number of livebirths (p for trend < 0.01), with early age at menopause (p = 0.03), and with later age at menarche (p = 0.11), whereas miscarriages and induced abortions were clearly unrelated. There were nonsignificant relations of disease risk with smoking (inverse), alcohol (inverse), and menopausal estrogens (positive), whereas oral contraceptive use was too uncommon to allow meaningful study. The lower risk of the disease associated with current occupations requiring manual activity (p = 0.03) and the lower, although not significantly so (p = 0.36), energy intake of cases in comparison to controls suggest that physical inactivity could be an important risk factor for endometrial cancer. Women with endometrial cancer were significantly taller than control women (p = 0.02). The latter results indicate that excess energy intake in early life, leading to higher attained stature, and excessive energy intake in later life, on account of physical inactivity and leading to higher body weight, converge in increasing the risk for endometrial cancer.

Diet and Coronary Heart Disease: A Case-Control Study in Athens, Greece

We conducted a case-control study in Athens, Greece, between January 1990 and April 1991 to examine the association between diet and coronary heart disease. The case series comprised 329 patients with electrocardiographically confirmed first coronary infarct or a first positive coronary arteriogram, or both, who were admitted to a major teaching hospital during a 16-month period. Controls were 570 patients admitted to the same hospital for minor conditions believed to be unrelated to nutrition. Total energy intake was inversely associated with coronary heart disease risk, a quintile energy increase corresponding to a relative risk of 0.96. After controlling for total energy intake, dietary fat was positively related to coronary heart disease, and total carbohydrates were negatively related to coronary heart disease, the nutrient-specific relative risks for a quintile increase being 1.19 (95% confidence interval = 0.96-1.48) and 0.81 (95% confidence interval = 0.67-0.97), respectively. Major fat components (saturated, monounsaturated, and polyunsaturated fat) did not appear to have differential risk implications for coronary heart disease; however, cooking with margarine was associated with an increased relative risk (1.87; 95% confidence interval = 0.82-4.28). Dietary proteins, cholesterol, and vitamin C were not associated with coronary heart disease.

A case-control study of air pollution and tobacco smoking in lung cancer among women in Athens☆

BACKGROUND A case-control study exploring the role of smoking and outdoor air pollution in the causation of lung cancer, by histologic type, in nonsmoking women, was undertaken in Athens between 1987 and 1989. METHODS One hundred one women with lung cancer and 89 comparison women with fractures or other orthopedic conditions, all permanent residents of Greater Athens, were included in the study. Smoking habits were ascertained through interviews, whereas lifetime exposure to air pollution was assessed by linking blindly lifelong residential and employment addresses of all subjects with objectively estimated or presumed air pollution levels. RESULTS The age-adjusted relative risk and 95% confidence intervals for lung cancer among current smokers compared with nonsmokers was 3.40 (1.75-6.61); it was 7.43 (2.88-19.13) among those smoking for more than 30 years and 7.46 (2.40-23.17) among those smoking more than 20 cigarettes per day. The age-adjusted relative risk was 1.70 (0.75-3.89) for adenocarcinoma and 6.45 (2.73-15.25) for other histologic types of lung cancer; statistically significant dose-response trends were evident for both histologic groups. Air pollution levels were associated with increased risk for lung cancer but the relative risk was small and statistically not significant. However, when both air pollution and duration (or quantity) of tobacco smoking, as well as their interaction, were introduced in a multiple logistic regression model, the interaction term was significant at the suggestive level of 0.10. CONCLUSION Whereas there is no effect of air pollution among nonsmokers, the relative risk contrasting extreme quartiles of air pollution among smokers of 30 years duration was 2.23. The interaction was almost exclusively accounted for by the nonadenocarcinoma lung tumors.

Induced abortion and ectopic pregnancy

Abstract The hypothesis that induced abortions increase the risk of ectopic implantation in subsequent pregnancies was evaluated in terms of a case-control approach. Obstetric and gynecologic histories were obtained from 30 women with a present or past history of ectopic pregnancy, hospitalized in the First or Second Obstetrical and Gynecological Clinics of the University of Athens Medical School. Three control subjects were drawn for each of the 26 patients with at least one earlier pregnancy, with matching of husbands education and age at the pregnancy whose order corresponded to the ectopic pregnancy in the propositus. The frequencies of positive histories of induced abortions in earlier pregnancies among these patients and control subjects were 58 and 24 per cent, respectively. This highly significant difference (P = 0.0004) points to a tenfold relative risk, and it suggests that, in Athens, half of ectopic implantations may be attributable to previous induced abortions.

INDUCED ABORTION AND SECONDARY INFERTILITY

The role of induced (and spontaneous) abortions in the aetiology of secondary sterility was investigated. Obstetric and gynaecologic histories were obtained from 100 women with secondary infertility admitted to the First Department of Obstetrics and Gynaecology of the University of Athens Medical School and to the Division of Fertility and Sterility of that Department. For every patient, an attempt was made to find two healthy control subjects from the same hospital with matching for age, parity, and level of education. Two control subjects each were found for 83 of the index patients. The relative risk of secondary infertility among women with at least one induced abortion and no spontaneous abortions was 3·4 times that among women without any induced or spontaneous abortions (95 per cent confidence interval 1·38–8·37). The relationship was statistically significant and indicated that in Greece, about 45 per cent of the cases of secondary infertility may be attributable to previous induced abortions.

INDUCED ABORTIONS, CONTRACEPTIVE PRACTICES, AND TOBACCO SMOKING AS RISK FACTORS FOR ECTOPIC PREGNANCY IN ATHENS, GREECE

Summary. A case‐control study of the role of induced abortion and other factors on the subsequent occurrence of ectopic pregnancy was undertaken in 1986–1987 in Athens, Greece, where a similar study 20 years ago found a tenfold risk of ectopic pregnancy among women with one or more illegal induced abortions. Seventy women residents of Athens, consecutively admitted to the major state maternity hospital with a diagnosis of ectopic pregnancy, were individually matched with women with a newly diagnosed pregnancy of the same order as the ectopic index pregnancy. Two control women were found for each of 63 cases, but only one control for each of the remaining seven cases. All cases and controls were interviewed by the same qualified obstetrician. Statistical analysis was undertaken with stratification of individual matched triplets and pairs, as well as through conditional multiple regression procedures. The relative risk of recurrence of an ectopic pregnancy was 6.39 with 95% confidence interval (CI) 1.96–21.04. Miscarriages did not increase the risk of ectopic pregnancy. The relative risk for subsequent ectopic pregnancy among women with one or more induced abortion, compared to women without such abortions, was 1.87 (CI 0.84–4.16) controlling only for the matching factors, and 1.71 (CI 0.69–4.27) when marital status (a possible selection factor) was also accounted for in the conditional logistic regression. There was no evidence for increasing risk with increasing number of induced abortions. Past use of an intrauterine device (IUCD) was associated with a relative risk of 3.89 (0.72–21.02); the relative risk increased with the duration of use of the IUCD. Tobacco smoking significantly increased the risk of an ectopic pregnancy, the relative risk being 2.35 (CI 1.19–4.67). Legalized induced abortions, as currently practised in Greece, do not appear to increase the relative risk of ectopic pregnancy to a substantial degree.

Induced abortions, miscarriages, and tobacco smoking as risk factors for secondary infertility.

STUDY OBJECTIVE--The aim was to determine whether induced abortions could increase the risk of secondary infertility. DESIGN--This was a case-control study; cases were women with secondary infertility, individually matched to two controls who were currently pregnant. Each participant was interviewed by one of two medical doctors using a questionnaire that sought information on their demographic, socioeconomic, medical, and reproductive status. The data were analysed by conditional logistic regression. SETTING--The study took place in the Alexandra Maternity Hospital in Athens, Greece, in 1987-88. PARTICIPANTS--84 women consecutively admitted with secondary infertility and 168 pregnant controls took part. MAIN RESULTS--Eight cases and no controls reported a previous ectopic pregnancy, confirming that the occurrence of a pregnancy of this type dramatically increases the risk of secondary infertility. Furthermore, the occurrence of either induced abortions or spontaneous abortions independently and significantly increased the risk of subsequent development of secondary infertility. The logistic regression adjusted relative risks (and 95% confidence intervals) for secondary infertility were 2.1 (1.1-4.0) when there was one previous induced abortion and 2.3 (1.0-5.3) when there were two previous induced abortions. Tobacco smoking significantly increased the risk of secondary infertility, the adjusted relative risk being 3.0 (1.3-6.8). CONCLUSIONS--Legalised induced abortions, as currently practised in Greece, appear to increase slightly the relative risk of secondary infertility.

PSYCHOMETRIC INTELLIGENCE DEFICITS IN LEAD-EXPOSED CHILDREN

The psychometric intelligence and the blood lead (PbB) of 509 children living near a lead smelter in Lavrion, Greece, were evaluated. The mean PbB was 23.7 μg/dl and the range 7.4–63.9 μg/dl. After controlling for 17 variables, including parent IQ, with a multiple linear regression model, it was found that PbB was significantly associated with full-scale IQ of the WISC-R (b = -0.270, p = 0.000069). Verbal and performance IQs were almost equally affected. The adjusted full-scale IQ difference between ‘high’ (>45 μg/dl) and ‘low’ PbB children was 9.1 units. The dose-response curve showed evidence of a threshold at the level of about 25 μg/dl PbB.

Time trends of tobacco smoking, air pollution, and lung cancer in Athens

Athens is a city with a serious air pollution problem which has existed for more than 20 years. To evaluate whether air pollution has affected lung cancer incidence (and hence, mortality) in the population of Athens we have compared standardized lung mortality between Athens and the rest of Greece taking into account the tobacco consumption trends in the respective populations and varying the postulated latency between 0 and 20 years. There is no evidence for an independent or interactive (with tobacco smoking) effect of air pollution on lung cancer mortality; the tobacco-adjusted mortality appears, if anything, lower in Athens than in the rest of Greece and the slopes of lung cancer mortality on tobacco consumption are almost identical in Athens and in the rest of Greece. By contrast, the same data are compatible with a strong effect of tobacco smoking on lung cancer mortality, an effect which appears to involve not only the early carcinogenic stages but also some of the later ones. The results of the present analysis do not support the hypothesis that air pollution, at least in Athens until 1980, has increased the incidence of lung cancer to an extent large enough to be detectable in ecological correlation analyses. Nevertheless the inherent limitations of these methods indicate that their results should be interpreted with caution and only as a step toward the gradual understanding of a complex issue.