Ulrich Bolm-Audorff

Cigarette smoking and bladder cancer in men : A pooled analysis of 11 case-control studies

The primary risk factor for bladder cancer is cigarette smoking. Using a combined analysis of 11 case‐control studies, we have accurately measured the relationship between cigarette smoking and bladder cancer in men. Available smoking information on 2,600 male bladder cancer cases and 5,524 male controls included duration of smoking habit, number of cigarettes smoked per day and time since cessation of smoking habit for ex‐smokers. There was a linear increasing risk of bladder cancer with increasing duration of smoking, ranging from an odds ratio (OR) of 1.96 after 20 years of smoking (95% confidence interval [CI] 1.48–2.61) to 5.57 after 60 years (CI 4.18–7.44). A dose relationship was observed between number of cigarettes smoked per day and bladder cancer up to a threshold limit of 15–20 cigarettes per day, OR = 4.50 (CI 3.81–5.33), after which no increased risk was observed. An immediate decrease in risk of bladder cancer was observed for those who gave up smoking. This decrease was over 30% after 1–4 years, OR = 0.65 (0.53–0.79), and was over 60% after 25 years of cessation, OR = 0.37 (0.30–0.45). However, even after 25 years, the decrease in risk did not reach the level of the never‐smokers, OR = 0.20. (0.17–0.24). The proportion of bladder cancer cases attributable to ever‐smoking was 0.66 (0.61–0.70) for all men and 0.73 (0.66–0.79) for men younger than 60. These estimates are higher than previously calculated. Int. J. Cancer 86:289–294, 2000.

Sinonasal cancer and occupational exposures: a pooled analysis of 12 case-control studies

Objective: In order to examine the associations between sinonasal cancer and occupational exposures other than wood dust and leather dust, the data from 12 case–control studies conducted in seven countries were pooled and reanalyzed. Methods: The pooled data set included 195 adenocarcinoma cases (169 men and 26 women), 432 squamous cell carcinomas (330 men and 102 women), and 3136 controls (2349 men and 787 women). Occupational exposures to formaldehyde, silica dust, textile dust, coal dust, flour dust, asbestos, and man-made vitreous fibers were assessed with a job-exposure matrix. Odds ratios (ORs) were adjusted for age, study, wood dust, and leather dust, or other occupational exposures when relevant. 95% confidence intervals (CIs) were estimated by unconditional logistic regression. Results: A significantly increased risk of adenocarcinoma was associated with exposure to formaldehyde. The ORs for the highest level of exposure were 3.0 (CI = 1.5–5.7) among men and 6.2 (CI = 2.0–19.7) among women. An elevated risk of squamous cell carcinoma was observed among men (OR = 2.5, CI = 0.6–10.1) and women (OR = 3.5, CI = 1.2–10.5) with a high probability of exposure to formaldehyde. Exposure to textile dust was associated with non-significantly elevated risk of adenocarcinoma, among women only: the OR for the high level of cumulative exposure was 2.5 (CI = 0.7–9.0). High level of asbestos exposure was associated with a significantly increased risk of squamous cell carcinoma among men (OR = 1.6, CI = 1.1–2.3). Conclusions: The results of this pooled analysis support the hypothesis that occupational exposure to formaldehyde increases the risk of sinonasal cancer, particularly of adenocarcinoma. They also indicate an elevated risk of adenocarcinoma among women exposed to textile dust, and suggest that exposure to asbestos may increase the risk of squamous cell carcinoma.

The contribution of cigarette smoking to bladder cancer in women (pooled European data).

AbstractBackground: Using a combined analysis of 11 case–control studies from Europe, we have investigated the relationship between cigarette smoking and bladder cancer in women.nMethods: Available smoking information on 685 female bladder cancer cases and 2416 female controls included duration of smoking habit, number of cigarettes smoked per day, and time since cessation of smoking habit for ex-smokers.nResults: There was an increasing risk of bladder cancer with increasing duration of smoking, ranging from approximately a two-fold increased risk for a duration of less than 10 years (odds ratio (OR) = 1.9, 95% confidence interval (CI) 1.1–3.1) to over a four-fold increased risk for a duration of greater than 40 years (OR = 4.1, 95% CI 3.0–5.5). A dose–response relationship was observed between number of cigarettes smoked per day and bladder cancer up to a threshold limit of 15–20 cigarettes per day, OR = 3.8 (95% CI 2.7–5.4), after which no increased risk was observed. An immediate decrease in risk of bladder cancer was observed for those who gave up smoking. This decrease was over 30% in the immediate 1–4 years after cessation, OR = 0.68 (95% CI 0.38–1.2). However, even after 25 years the decrease in risk did not reach the level of the never-smokers, OR = 0.27 (95% CI 0.21–0.35).nConclusion: The proportion of bladder cancer cases among women attributable to ever smoking was 0.30, (0.25–0.35) and to current smoking was 0.18 (0.14–0.22). These attributable proportions are less than those observed among men, although they are likely to increase in the future as the smoking-related disease epidemic among women matures.

Sinonasal cancer, occupation, and tobacco smoking in European women and men

BACKGROUNDnIn this analysis of European case-control studies on sinonasal cancer, we examined the risk for occupation and smoking, by gender and histological type.nnnMETHODSnThe pooled data included 104 female and 451 male cases, and 241 female and 1,464 male controls. Lifetime smoking and occupational history were recoded following uniform criteria, and job-exposure matrices were applied for wood and leather dust.nnnRESULTSnWood dust exposure was associated with an excess risk in men (OR = 2.36, 95% CI 1.75-3.2) but not in women (OR = 1.17, 95% CI 0.31-4.47). Exposure to leather dust was associated with an excess risk in both genders. Both wood and leather dust were associated with adenocarcinomas rather than squamous cell carcinomas. Excess risks for smoking were higher for squamous cell carcinomas and higher in men than in women.nnnCONCLUSIONSnIn these European populations, occupation was associated with about 11% of all sinonasal cancers in women and 39% in men. This difference can, in part, be attributed to variation in exposure patterns between genders.

Occupation and bladder cancer in European women.

Objectives: We examined the importance of occupational exposures for bladder cancer in women.Methods: We combined data from 11 case-control studies conducted between 1976 and 1996 in six European countries. The pooled data comprised 700 incident female cases and 2425 population or hospital controls, aged 30–79 years. Lifetime occupational and smoking history were examined using common coding.Results: Excess risks were found in only a few of the occupations previously identified at high risk for bladder cancer. Statistically significant excess risks were observed for metal workers, particularly blacksmiths, toolmakers and machine tool operators (OR: 2.0, 95% CI: 1.1–3.6), tobacco workers (OR: 3.1, 95% CI: 1.1–9.3), field crop and vegetable farm workers (OR: 1.8, 95% CI: 1.0–3.1), tailors and dress makers (OR: 1.4, 95% CI: 1.0–2.1), saleswomen (OR: 2.6, 95% CI: 1.0–6.9), and mail sorting clerks (OR: 4.4, 95% CI: 1.0–19.5). About 8% (95% CI: 3.1–19.9) of all bladder cancers in women could be attributed to occupation after adjusting for smoking. The attributable risk was higher in women aged less than 65 years (12%), compared to older women (4%).Conclusions: The calculation of the attributable risk on the basis of results from this analysis may have caused some overestimation of the proportion of occupational bladder cancer in women. A significant proportion, however, of bladder cancer cases among European women less than 65years is likely to be attributed to occupation. This link between bladder cancer in women and occupational factors has received little recognition, probably because studies addressing these issues have predominantly been done in men.

Non-occupational risk factors for cancer of the lower urinary tract in Germany.

In a hospital-based case–control study conducted between 1989 and 1992 in Hessen (West-Germany) 300 cases (239 male and 61 female) of histologically confirmed cancer of the lower urinary tract (LUT) were individually matched to controls from the same hospitals with respect to sex, age and area of residence. Smoking of cigarettes was associated with an elevated risk of 2.80 in males (95% confidence interval (CI): 1.65–4.76) and 5.33 (95% CI: 1.55–18.33) in females, as compared with non-smokers. Variables like daily amount of smoked cigarettes, duration of smoking, age at beginning of cigarette smoking and time since smoking cessation showed a clear dose- and time–response relationship in males, but not in females. Elevated risks were observed for higher consumption of coffee, beer and wine, but – especially for the consumption of coffee – were drastically reduced after adjustment for smoking. A weak association was found between the daily fluid intake and bladder cancer in males. Among females a significantly decreased odds ratio (OR) of 0.34 (95% CI: 0.11–0.99) was found for a daily fluid intake of more than two liters. Protective effects and risk reductions of approximately 50% were found for the regular intake of raw carrots, kale, salads and fruits. The findings of this investigation support an association between lifestyle factors and cancer of the lower urinary tract.

Tobacco, occupation and non-transitional-cell carcinoma of the bladder : An international case-control study

Transitional-cell carcinoma is the dominant histological type of malignant tumors of the urinary bladder. There is limited information on risk factors for non-transitional-cell carcinoma (NTCC) of the bladder. We used data from 9 case-control studies on bladder cancer from 6 European countries to examine the association between NTCC, tobacco smoking and occupation. Information on 146 cases diagnosed with NTCC were matched by age, gender and study center to 727 non-cancer population or hospital controls and also with 722 transitional-cell-bladder-cancer controls. Lifetime smoking and occupational history were evaluated. A statistically significant excess risk for NTCC was observed for current smoking [odds ratio (OR) = 3.61, 95% confidence interval (CI) 2.08-6.28]. The risk increased with higher tobacco consumption (OR for highest tertile of pack-years = 7.01, 95% CI 3.60-13.66). The risks were higher for squamous-cell carcinomas than for other types of NTCC. Among major occupational groups, a significant excess risk was seen for field-crop and vegetable-farm workers (OR = 2.06, 95% CI 1.03-4.10). These results indicate that NTCC of the bladder is associated with smoking and specific occupations. The risk pattern seems to differ, in part, from that observed for transitional-cell carcinoma of the bladder.

Sinonasal cancer and occupation. Results from the reanalysis of twelve case-control studies

A pooled reanalysis of twelve case-control studies on sinonasal cancer and occupation from seven countries was conducted in order to study associations with occupations other than wood- and leather-related occupations. The pooled data set included a total of 930 cases (680 men and 250 women) and 3,136 controls (2,349 men and 787 women). All the studies included a detailed occupational history for cases and controls. Each job was coded using the same classifications for occupation and industry. Two approaches were used in the analysis: systematic analysis of occupations; a priori analysis using a preestablished list of occupations and industries. The results confirmed associations observed in several studies not included in this analysis. For agricultural workers, significant excesses were observed for squamous cell carcinoma among women (OR = 1.69) and men (OR = 3.72 for ten years or more of employment as an orchard worker), and adenocarcinomas among men (OR = 2.98 for ten years or more of employment). Associations with textile occupations were observed for adenocarcinoma among women (OR = 2.60) and squamous cell carcinoma among men (OR = 5.09 for fiber preparers, 3.01 for bleachers). Elevated risks for both histologic types were observed among men employed in food manufacturing (OR = 3.25, adenocarcinoma), or as food preservers (OR = 13.9, squamous cell carcinoma), and among men employed as cooks (OR = 1.99, squamous cell carcinoma). A positive association with squamous cell carcinoma was observed for male transport equipment operators (OR = 1.21), and also with adenocarcinoma for male motor-vehicle drivers (OR = 2.50). A number of other associations were observed in the systematic analysis.

Lung cancer risk and welding: Results from a case-control study in Germany

In a case-control study, 839 male hospital-based cases of primary lung cancer and the same number of population-based controls--matched by sex, age, and region of residence--were personally interviewed for their job and smoking histories. The study allows to quantify occupational asbestos exposure that was thought to be a welding-associated risk: 6% of cases and 2% of controls were classified into the occupational category welders or burners# (odds ratio [OR] = 2.65). This OR was reduced to 1.93 (95% confidence limit [CL]: 1.03-3.61) after adjustment for smoking and asbestos. In contrast, a history of welding in general for at least a half-year is 28% among cases and 23% among controls, yielding an OR of 1.25 (95% CL: 0.94-1.65) after adjustment for both confounders. The OR of welding for more than 6,000 hr is 1.45 (95% CL = 1.04-2.02), reduced to 1.10 after adjustment for smoking and asbestos. Oxyacetylene welding for more than 6,000 hr lifelong is associated with an OR of 1.86 (95% CL = 1.01-3.43) reduced to 1.46 (n.s.) after adjustment for smoking and asbestos. The risk of oxyacetylene welding seems to be highest for oat cell carcinoma with an adjusted OR for ever-exposure of 1.46 (95% CL = 0.69-3.10). Therefore, the present study supports the hypothesis that some, but not all, of the excess risk of welders observed in the literature may be due to a history of cigarette smoking and occupational asbestos exposure. The elevated risk for the subgroup of employees in the aircraft industry reported for the midterm evaluation of the study still prevails, though no longer statistically significant. However, employees in this industry who ever welded show an OR of 2.29 (95% CL = 1.19-4.42) after adjustment for smoking and asbestos.

Smoking as a confounder in case‐control studies of occupational bladder cancer in women

BACKGROUNDnIn studies in men, risk estimates on occupation and bladder cancer are distorted by about 10% when not adjusting for smoking. We examined the degree to which occupational risk estimates for bladder cancer in women are confounded by smoking, and the degree of residual confounding by inadequate control of this effect.nnnMETHODSnPrimary data of 11 case-control studies on occupation and bladder cancer from Denmark, France, Germany, Greece, Italy, and Spain were pooled. Information for smoking and lifetime occupational history for 700 female cases and 2,425 female controls ages 30-79 was abstracted and recoded. Logistic regression was used to calculate odds ratios (OR) by occupation, applying five models which differed in their degree of adjustment for smoking.nnnRESULTSnIn major occupational groups, risk estimates were distorted by less than 10% when not adjusting for smoking. A statistically significant excess risk for bladder cancer was found in 13 specific occupations and industries. In most occupations, adjustment for smoking led the ORs towards the null value, but all statistically significant associations were maintained after adjustment. In three occupations (lathe operators, field crop workers, and wood manufacturers), a statistically significant excess risk was masked when not adjusting for smoking. In six occupations, estimates were distorted by more than 10% (-22% up to +40%). In occupations where smoking acted as a positive confounder, the proportion of confounding removed using a dichotomous smoking variable (ever/never) was around 60%. In one occupation (buyers), controlling for smoking status (ever, never) led to over-adjustment, because the percentage of smokers was high but the quantity smoked was low.