广州地区肺癌的病例-对照研究

目的探讨广州地区人群发生肺癌的危险因素.方法将1998-2001年新诊断的原发性肺癌病例445例按性别、年龄1∶1配对选取445例健康者进行对照研究、问卷调查、建立数据库、单因素分析和多因素条件Logistic回归分析,筛选肺癌的主要危险因素.结果单因素分析发现32个暴露因素与肺癌发生有关;多因素分析发现肺癌有9个主要危险因素和1个保护因素,他们是1)吸烟OR及95%CI为3.19(2.18～4.67);2)被动吸烟来源于父亲OR为2.43(1.51～3.90);3)被动吸烟来源于配偶OR为2.33(1.26～4.30);4)肺结核病史OR为2.36(1.13～4.94);5)家庭用煤为燃料OR为3.44(1.38～8.57);6)常食用腌、酸菜OR为3.83(2.34～6.27);7)常食用咸鱼OR为4.49(2.86～7.06);8)经常下厨用猛火炒菜OR为4.45(3.03～6.56);9)职业接触金属类毒物OR为8.76(2.28～33.64).10)经常体育锻炼OR为0.59(0.33～1.06),可能是一个候选的保护因素.结论肺癌的发生与多种暴露因素有关,从其病因学来看,肺癌是可以预防与控制的.     

The LLP risk model: an individual risk prediction model for lung cancer

Using a model-based approach, we estimated the probability that an individual, with a specified combination of risk factors, would develop lung cancer within a 5-year period.Data from 579 lung cancer cases and 1157 age- and sex-matched population-based controls were available for this analysis. Significant risk factors were fitted into multivariate conditional logistic regression models. The final multivariate model was combined with age-standardised lung cancer incidence data to calculate absolute risk estimates.Combinations of lifestyle risk factors were modelled to create risk profiles. For example, a 77-year-old male non-smoker, with a family history of lung cancer (early onset) and occupational exposure to asbestos has an absolute risk of 3.17% (95% CI, 1.67-5.95). Choosing a 2.5% cutoff to trigger increased surveillance, gave a sensitivity of 0.62 and specificity of 0.70, while a 6.0% cutoff gave a sensitivity of 0.34 and specificity of 0.90. A 10-fold cross validation produced an AUC statistic of 0.70, indicating good discrimination.If independent validation studies confirm these results, the LLP risk models' application as the first stage in an early detection strategy is a logical evolution in patient care.     

A retrospective study on malignant neoplasms of bladder, lung and liver in blackfoot disease endemic area in Taiwan

A total of 69 bladder cancer, 76 lung cancer and 59 liver cancer deceased cases and 368 alive community controls group-matched on age and sex were studied to evaluate the association between high-arsenic artesian well water and cancers in the endemic area of blackfoot disease (BFD), a unique peripheral vascular disease related to continuous arsenic exposure. According to a standardized structured questionnaire, information on risk factors was obtained through proxy interview of the cases and personal interview of the controls. A positive dose-response relationship was observed between the exposure to artesian well water and cancers of bladder, lung and liver. The age-sex-adjusted odds ratios of developing bladder, lung and liver cancers for those who had used artesian well water for 40 or more years were 3.90, 3.39, and 2.67, respectively, as compared with those who never used artesian well water. Multiple binary logistic regression analyses showed that the dose-response relationships and odds ratios remained much the same while other risk factors were further adjusted.     

Air pollution and lung cancer mortality in the vicinity of a nonferrous metal smelter in Sweden

To evaluate the importance of exposure to ambient air pollution for lung cancer risk, we conducted a case-control study in the vicinity of a nonferrous metal smelter. The smelter started operations in 1930 and had very high emissions during the early decades, particularly of arsenic and SO(2). Among subjects deceased 1961-1990 in the municipality where the smelter is located and who had not worked at the smelter, 209 male and 107 female lung cancer cases were identified and matched by sex and year of birth to 518 and 209 controls, respectively. Information on smoking habits, occupations and residences was collected by questionnaire to next-of-kin and from registry data. Living close to the smelter was associated with a relative risk (RR) for lung cancer of 1.38 [95% confidence interval (CI) 0.89-2.14] among men, adjusted for smoking and occupational exposures. No clear difference in risk was detected for men deceased 1961-1979 compared to men deceased 1980-1990 (RR point estimates 1.42 and 1.29, respectively). There appeared to be an increased risk especially for men exposed in the beginning of the operations (RR = 1.51, 95% CI 0.90-2.54), in particular combined with exposure duration shorter than 20 years (RR = 2.52, 95% CI 0.89-7.11). For women, however, no overall increased risk for lung cancer was observed. Although not significant, our findings thus indicated an increased risk of lung cancer among men living close to the nonferrous smelter. This increase appeared to concern primarily men exposed during the early years of operations, when emissions were very high.     

Lung cancer in lifetime nonsmoking men - results of a case-control study in Germany

Epidemiological studies of lung cancer among nonsmoking men are few. This case-control study was conducted among lifetime nonsmoking men between 1990 and 1996 in Germany to examine lung cancer risk in relation to occupation, environmental tobacco smoke, residential radon, family history of cancer and previous lung disease. A total of 58 male cases with confirmed primary lung cancer and 803 male population controls who had never smoked more than 400 cigarettes in their lifetime were personally interviewed by a standardized questionnaire. In addition, 1-year radon measurements in the living and bedroom of the subjects' last dwelling were carried out. Unconditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI). Having ever worked in a job with known lung carcinogens was associated with a two-fold significantly increased lung cancer risk (OR = 2.2; CI = 1.0-5.0), adjusted for age and region. The linear trend test for lung-cancer risk associated with radon exposure was close to statistical significance, demonstrating an excess relative risk for an increase in exposure of 100 Bq m(-3)of 0.43 (P = 0.052). Nonsignificantly elevated effects of exposure to environmental tobacco smoke in public transportation and in social settings were observed. No associations with a family history of cancer or previous lung diseases were found. Our results indicate that occupational carcinogens and indoor radon may play a role in some lung cancers in nonsmoking men.     

Occupational risk factors have to be considered in the definition of high-risk lung cancer populations

Background:

The aim of this study was to compute attributable fractions (AF) to occupational factors in an area in North-Eastern France with high lung cancer rates and a past of mining and steel industry.

Methods:

A population-based case–control study among males aged 40–79 was conducted, including confirmed primary lung cancer cases from all hospitals of the study region. Controls were stratified by broad age-classes, district and socioeconomic classes. Detailed occupational and personal risk factors were obtained in face-to-face interviews. Cumulative occupational exposure indices were obtained from the questionnaires. Attributable fractions were computed from multiple unconditional logistic regression models.

Results:

A total of 246 cases and 531 controls were included. The odds ratios (ORs) adjusted on cumulative smoking and family history of lung cancer increased significantly with the cumulative exposure indices to asbestos, polycyclic aromatic hydrocarbons and crystalline silica, and with exposure to diesel motor exhaust. The AF for occupational factors exceeded 50%, the most important contributor being crystalline silica and asbestos.

Conclusion:

These AFs are higher than most published figures. This can be because of the highly industrialised area or methods for exposure assessments. Occupational factors are important risk factors and should not be forgotten when defining high-risk lung cancer populations.     

A case-control study of lung cancer in Casablanca,Morocco

Objective: To evaluate etiologic risk factors for lung cancer in Casablanca, Morocco. Methods: We conducted a hospital-based case–control study that included 118 incident lung cancer cases and 235 age-, sex- and residence-matched controls. We analyzed the data using matched univariate and matched and unmatched multivariate logistic regression analyses. Results: Active tobacco smoking and history of chronic bronchitis were the strongest risk factors for lung cancer in the matched logistic regression model. Multivariate odds ratio (OR) and 95% confidence intervals varied from 1.79 (0.47–6.79) for former light smokers to 26.07 (6.58–103.27) for current heavy tobacco smokers at the time of disease occurrence. Combined use of hashish/kiff and snuff had an OR of 6.67 (1.65–26.90), whereas the OR for hashish/kiff (without snuff) was 1.93 (0.57–6.58). History of chronic bronchitis had an OR of 4.16 (1.76–9.85). Other slightly increased risks of lung cancer were found for exposure to passive smoking (1.36; 0.71–2.62), occupational exposures (1.75; 0.84–3.63), use of candles for lighting (1.44; 0.42–5.01), and poor ventilation of the kitchen (1.22; 0.57–2.58). Conclusions: This study confirms known risk factors for lung cancer and uncovers potential new etiologic ones such as the role of hashish/kiff.     

Lung cancer after exposure to disease modifying anti-rheumatic drugs

OBJECTIVE: To assess the effects of disease modifying anti-rheumatic drugs (DMARDs) on lung cancer risk in a large rheumatoid arthritis (RA) cohort. METHODS: We assembled a cohort of RA patients (N=23,810) from population-based administrative healthcare databases. We ascertained cases of lung cancer in the cohort using physician billing and hospitalization records. Each lung cancer case was age and sex matched to 10 controls. We used conditional logistic regression to determine the effects of DMARDs on lung cancer risk, calculating the adjusted rate ratio (RR) attributable to each DMARD. RESULTS: Subjects were followed for a total of 157,204 person-years. During this time, 960 cases of lung cancer were recorded. The frequency of exposures to various DMARDs was similar in cases and controls; our adjusted RR estimates, reflecting the independent effects of each DMARD exposure, did not associate any of the drugs with an increased risk of lung cancer. CONCLUSIONS: Our data do not suggest that DMARD exposures are the primary mediator of lung cancer risk in RA. An increased risk of lung cancer in RA patients may be related to other determinants, including shared risk factors for the development of both RA and lung cancer.     

The roles of smoking and cooking emissions in lung cancer risk among Chinese women in Hong Kong

BackgroundWe conducted this case–control study to evaluate smoking effect on lung cancer conditional on the level of exposure to cooking emissions and to explore whether there is a joint effect of these two risk factors.Subjects and methodsWe selected 279 newly diagnosed primary lung cancer cases and 322 community controls from Hong Kong females, frequency matched by age group, and collected relevant data. We applied logistic regression to estimate lung cancer risk related to smoking and cooking fume exposure, expressed as total cooking dish-years, while adjusting for various potential confounding factors.ResultsCurrent smoking was associated with four-fold increased risk, and ex-smoking with two-fold risk, which was not much influenced by cooking dish-years. No increased risk was observed in environmental tobacco smoking. Increasing intakes of yellow/orange vegetables and multivitamins were significant protective factors in all models. In the analysis of joint effect, the combination of smoking and cooking dish-years tended to have a greater risk than exposure to cooking fumes alone. There was a dose–response gradient with total dish-years in nonsmokers, but not in smokers. Smoking was more strongly associated with nonadenocarcinoma, whereas exposure to cooking fumes appeared to be related to both adenocarcinoma and nonadenocarcinoma.ConclusionWe confirmed the important roles of smoking and cooking emissions in lung cancer risk among the women. These two major risk factors appeared to act independently.     

Case-Control Study of Occupational Categories and BreastCancer Risk in Thailand

Breast cancer is common malignancy in Thai female. Although there are well established risk factors, manyenvironmental agents with an impact are still unknown especially with reference to occupation. The objective ofthis study was to investigate the risk of female breast cancer among different occupational categories in Thailand.A frequency-matched case-control study was conducted among Thai women aged 17-79 . A total of 516 pairs ofcases and controls were recruited at the Thai National Cancer Institute, Khon Kaen University Hospital andKhon Kaen Provincial Hospital during 2002-2004. Cases were newly diagnosed with histological confirmed breastcancers while controls were selected from healthy women matched by age (±5 years) and geographical area. Afterinformed consent was signed, information was obtained on occupation and other risk factors from each subjectusing an interviewer-administered and structured questionnaire. The International Standard Classificationof Occupations version 1968 (ISCO-68) was used to code for occupational categories. The relation betweenoccupational categories and breast cancer risk was evaluated by unconditional logistic regression analysis. Themean age of cases and controls were 46.9±10.6 and 47.8±9.9 years, respectively. Fifty-five percent of cases werepre-menopausal women. After adjusting for confounding factors by multiple logistic regression analysis, theresults showed that occupational category as production and related workers, transport equipment operatorsand labourers was associated with an increased risk of breast cancer (OR=1.41 95% CI=1.01-1.97) and thisfinding was also supported by a statistically significant positive trend for duration of employment (p=0.01). Asignificantly decreased breast cancer risk was observed in clerks (OR=0.59, 95% CI=0.37-0.96). In conclusion,this study revealed that women who have lifetime occupation in an industrial setting may have higher risk todevelop breast cancer. Further studies are needed to assess occupational exposure in specific occupations.