Measures of body fatness and height in early and mid-to-late adulthood and prostate cancer: risk and mortality in The Pooling Project of Prospective Studies of Diet and Cancer.

BACKGROUND: Advanced prostate cancer etiology is poorly understood. Few studies have examined associations of anthropometric factors (e.g. early adulthood obesity) with advanced prostate cancer risk. PATIENTS AND METHODS: We carried out pooled analyses to examine associations between body fatness, height, and prostate cancer risk. Among 830 772 men, 51 734 incident prostate cancer cases were identified, including 4762 advanced (T4/N1/M1 or prostate cancer deaths) cases, 2915 advanced restricted (same as advanced, but excluding localized cancers that resulted in death) cases, 9489 high-grade cases, and 3027 prostate cancer deaths. Cox proportional hazards models were used to calculate study-specific hazard ratios (HR) and 95% confidence intervals (CI); results were pooled using random effects models. RESULTS: No statistically significant associations were observed for body mass index (BMI) in early adulthood for advanced, advanced restricted, and high-grade prostate cancer, and prostate cancer mortality. Positive associations were shown for BMI at baseline with advanced prostate cancer (HR = 1.30, 95% CI = 0.95-1.78) and prostate cancer mortality (HR = 1.52, 95% CI = 1.12-2.07) comparing BMI ≥35.0 kg/m2 with 21-22.9 kg/m2. When considering early adulthood and baseline BMI together, a 27% higher prostate cancer mortality risk (95% CI = 9% to 49%) was observed for men with BMI <25.0 kg/m2 in early adulthood and BMI ≥30.0 kg/m2 at baseline compared with BMI <25.0 kg/m2 in early adulthood and BMI <30.0 kg/m2 at baseline. Baseline waist circumference, comparing ≥110 cm with <90 cm, and waist-to-hip ratio, comparing ≥1.00 with <0.90, were associated with significant 14%-16% increases in high-grade prostate cancer risk and suggestive or significant 20%-39% increases in prostate cancer mortality risk. Height was associated with suggestive or significant 33%-56% risks of advanced or advanced restricted prostate cancer and prostate cancer mortality, comparing ≥1.90 m with <1.65 m. CONCLUSION: Our findings suggest that height and total and central adiposity in mid-to-later adulthood, but not early adulthood adiposity, are associated with risk of advanced forms of prostate cancer. Thus, maintenance of healthy weight may help prevent advanced prostate cancer.

Influence of anti-inflammatory diet and smoking on mortality and survival in men and women: two prospective cohort studies.

BACKGROUND: The associations between an anti-inflammatory diet and both all-cause and cause-specific mortality have been studied previously; however, the influence of an anti-inflammatory diet on survival time has not been investigated. Moreover, the potential modification of these associations by smoking status remains unclear. OBJECTIVE: The aims of this study were to examine the associations between an anti-inflammatory diet index (AIDI) and all-cause and cause-specific mortality, to determine the association between the AIDI and differences in survival time and to assess effect modification by smoking status. METHODS: The study population included 68 273 Swedish men and women (aged 45-83 years) at baseline. The anti-inflammatory potential of the diet was estimated using the validated AIDI, which includes 11 potential anti-inflammatory and five potential pro-inflammatory foods. Cox proportional hazards and Laplace regression were used to estimate hazard ratios and differences in survival time. RESULTS: During 16 years of follow-up (1 057 959 person-years), 16 088 deaths [5980 due to cardiovascular disease (CVD) and 5252 due to cancer] were recorded. Participants in the highest versus lowest quartile of the AIDI had lower risks of all-cause (18% reduction, 95% CI: 14-22%), CVD (20%, 95% CI: 14-26%) and cancer (13%, 95% CI: 5-20%) mortality. The strongest inverse associations between the highest and lowest quartiles of AIDI and risk of mortality were observed in current smokers: 31%, 36% and 22% lower risks of all-cause, CVD and cancer mortality, respectively. The difference in survival time between current smokers in the lowest AIDI quartile and never smokers in the highest quartile was 4.6 years. CONCLUSION: Adherence to a diet with high anti-inflammatory potential may reduce all-cause, CVD and cancer mortality and prolong survival time especially amongst smokers.

Coffee, tea, and caffeine intake and amyotrophic lateral sclerosis mortality in a pooled analysis of eight prospective cohort studies.

BACKGROUND AND PURPOSE: Caffeine is associated with a lower risk of some neurological diseases, but few prospective studies have investigated caffeine intake and risk of amyotrophic lateral sclerosis (ALS) mortality. We therefore determined associations between coffee, tea and caffeine intake, and risk of ALS mortality. METHODS: We conducted pooled analyses of eight international, prospective cohort studies, including 351 565 individuals (120 688 men and 230 877 women). We assessed coffee, tea and caffeine intake using validated food-frequency questionnaires administered at baseline. We used Cox regression to estimate study- and sex-specific risk ratios and 95% confidence intervals (CI) for ALS mortality, which were then pooled using a random-effects model. We conducted analyses using cohort-specific tertiles, absolute common cut-points and continuous measures of all exposures. RESULTS: During follow-up, 545 ALS deaths were documented. We did not observe statistically significant associations between coffee, tea or caffeine intake and risk of ALS mortality. The pooled multivariable risk ratio (MVRR) for ≥3 cups per day vs. >0 to <1 cup per day was 1.04 (95% CI, 0.74-1.47) for coffee and 1.17 (95% CI, 0.77-1.79) for tea. The pooled MVRR comparing the highest with the lowest tertile of caffeine intake (mg/day) was 0.99 (95% CI, 0.80-1.23). No statistically significant results were observed when exposures were modeled as tertiles or continuously. CONCLUSIONS: Our results do not support associations between coffee, tea or total caffeine intake and risk of ALS mortality.

Coffee consumption and risk of aortic valve stenosis: A prospective study.

BACKGROUND AND AIMS: Coffee contains many biologically active compounds with potential adverse or beneficial effects on the cardiovascular system. Whether coffee consumption is associated with the risk of aortic valve stenosis (AVS) is unknown. The purpose of this study was therefore to examine the association between coffee consumption and AVS incidence. METHODS AND RESULTS: This prospective study included 71 178 men and women who provided information on their coffee consumption through a questionnaire at baseline. Incident cases of AVS were identified through linkage with the Swedish National Patient and Cause of Death Registers. During a mean follow-up of 15.2 years, 1295 participants (777 men and 518 women) were diagnosed with AVS. Coffee consumption was positively associated with risk of AVS in a dose-response manner after adjustment for age, sex, smoking, and other risk factors (P-trend = 0.005). The multivariable hazard ratios were was 1.11 (95% confidence interval 1.04-1.19) per 2 cups/day increase of coffee consumption and 1.65 (95% confidence interval 1.10-2.48) when comparing the highest (≥6 cups/day) with the lowest (<0.5 cup/day) category of coffee consumption. The association was not modified by other risk factors. CONCLUSIONS: This study provides novel evidence that high coffee consumption is associated with an increased risk of AVS.

Dietary total antioxidant capacity in early school age and subsequent allergic disease.

BACKGROUND: Dietary antioxidant intake has been hypothesized to influence the development of allergic diseases; however, few prospective studies have investigated this association. OBJECTIVE: Our aim was to study the association between total antioxidant capacity (TAC) of the diet at age 8 years and the subsequent development of asthma, rhinitis and sensitization to inhalant allergens between 8 and 16 years, and to assess potential effect modification by known risk factors. METHODS: A total of 2359 children from the Swedish birth cohort BAMSE were included. Dietary TAC at age 8 years was estimated by combining information on the child's diet the past 12 months from a food frequency questionnaire with a database of common foods analysed with the oxygen radical absorbance capacity method. Classification of asthma and rhinitis was based on questionnaires, and serum IgE antibodies were measured at 8 and 16 years. RESULTS: A statistically significant inverse association was observed between TAC of the diet and incident sensitization to inhalant allergens (adjusted odds ratio: 0.73, 95% confidence interval: 0.55-0.97 for the third compared to the first tertile, P-value for trend = 0.031). Effect modification by traffic-related air pollution exposure was observed, with a stronger association between dietary TAC and sensitization among children with low traffic-related air pollution exposure (P-value for interaction = 0.029). There was no evidence for effect modification by GSTP1 or TNF genotypes, although these results should be interpreted with caution. No clear associations were observed between TAC and development of rhinitis or asthma, although a significant inverse association was observed for allergic asthma (ORadj 0.57, 95% CI 0.34-0.94). CONCLUSIONS AND CLINICAL RELEVANCE: Higher TAC of the diet in early school age may decrease the risk of developing sensitization to inhalant allergens from childhood to adolescence. These findings indicate that implementing an antioxidant-rich diet in childhood may contribute to the prevention of allergic disease.

Cohort study of corticosteroid use and risk of hospital admission for diverticular disease.

BACKGROUND: Medication has been suggested as a potential risk factor for diverticular disease. The objective of this study was to investigate the association between the intake of corticosteroids, indometacin or aspirin and diverticular disease. METHOD: This was a prospective population-based cohort study of middle-aged women in the Swedish Mammography Cohort. Use of corticosteroids (oral or inhaled), indometacin or aspirin in 1997 was determined from questionnaires. Cases of diverticular disease were identified from the Swedish national registers until the end of 2010. The relative risk (RR) of diverticular disease requiring hospital admission according to the use of medication was estimated using Cox proportional hazards models, adjusted for age, body mass index, physical activity, fibre intake, diabetes, hypertension, alcohol, smoking and education. RESULTS: A total of 36 586 middle-aged women in the Swedish Mammography Cohort were included, of whom 674 (1.8 per cent) were hospitalized with diverticular disease at least once. Some 7.2 per cent of women reported intake of oral corticosteroids and 8.5 per cent use of inhaled corticosteroids. In multivariable analysis, women who reported oral corticosteroid intake had a 37 per cent (RR 1.37, 95 per cent c.i. 1.06 to 1.78; P = 0.012) increased risk of diverticular disease compared with those who reported no intake at all. Use of inhaled corticosteroids was associated with an even more pronounced increase in risk of 71 per cent (RR 1.71, 1.36 to 2.14; P < 0.001). There was a significant dose-response relationship, with the risk increasing with longer duration of inhaled corticosteroids (P for trend < 0.001). Use of indometacin (2.5 per cent of women) or aspirin (44.2 per cent) did not influence the risk. CONCLUSION: There was a significant relationship between corticosteroids (especially inhaled) and diverticular disease requiring hospital admission.

Dairy products and pancreatic cancer risk: a pooled analysis of 14 cohort studies.

Pancreatic cancer has few early symptoms, is usually diagnosed at late stages, and has a high case-fatality rate. Identifying modifiable risk factors is crucial to reducing pancreatic cancer morbidity and mortality. Prior studies have suggested that specific foods and nutrients, such as dairy products and constituents, may play a role in pancreatic carcinogenesis. In this pooled analysis of the primary data from 14 prospective cohort studies, 2212 incident pancreatic cancer cases were identified during follow-up among 862 680 individuals. Adjusting for smoking habits, personal history of diabetes, alcohol intake, body mass index (BMI), and energy intake, multivariable study-specific hazard ratios (MVHR) and 95% confidence intervals (CIs) were calculated using the Cox proportional hazards models and then pooled using a random effects model. There was no association between total milk intake and pancreatic cancer risk (MVHR = 0.98, 95% CI = 0.82-1.18 comparing ≥500 with 1-69.9 g/day). Similarly, intakes of low-fat milk, whole milk, cheese, cottage cheese, yogurt, and ice-cream were not associated with pancreatic cancer risk. No statistically significant association was observed between dietary (MVHR = 0.96, 95% CI = 0.77-1.19) and total calcium (MVHR = 0.89, 95% CI = 0.71-1.12) intake and pancreatic cancer risk overall when comparing intakes ≥1300 with <500 mg/day. In addition, null associations were observed for dietary and total vitamin D intake and pancreatic cancer risk. Findings were consistent within sex, smoking status, and BMI strata or when the case definition was limited to pancreatic adenocarcinoma. Overall, these findings do not support the hypothesis that consumption of dairy foods, calcium, or vitamin D during adulthood is associated with pancreatic cancer risk.

Recurrent reactions to food among children at paediatric emergency departments: epidemiology of allergic disease.

BACKGROUND: Knowledge about repeated food reactions in paediatric emergency departments (ED) is sparse. OBJECTIVE: To investigate the incidence and potential risk factors for repeated ED visits for food-allergic reactions among children with a prior ED visit due to reactions to food. METHODS: A total of 358 children with ED visits at paediatric hospitals in Stockholm due to reactions to foods during 2007 (index-reaction) were investigated in relation to recurrent reactions until 30 June 2010. Adjusted Cox proportional hazard models were used to compute relative risks (RR) and 95% confidence intervals (CI). RESULTS: A total of 80 children had 116 ED revisits over a period of 873 patient-years, yielding an incidence rate of 9 per 100 patient-years. Known food allergy before the index ED visit in 2007 increased the risk for ED revisits (RR = 2.30, 95% CI 1.35-3.94). Likewise, prescription of adrenaline auto-injector before the index-reaction increased the risk (RR = 2.02, 95% CI 1.17-3.49). Twenty-one percent of the children had more severe reactions at the revisit, 38% less severe and 41% had reactions of comparable severity. However, among 44% of the children with comparable or less severe reaction at revisit, early treatment with adrenaline hampered the classification of change in severity. CONCLUSIONS AND CLINICAL RELEVANCE: Previously known food allergy and prior prescription of adrenaline are significant risk factors for ED revisits among children with a prior ED visit due to reactions to food. Our results indicate that the severity of the index-reaction cannot be used to predict the severity of the relapse.

Antioxidant intake and allergic disease in children.

BACKGROUND: Antioxidant intake may reduce the risk of allergic disease by protecting against oxidative tissue damage. Major sources of antioxidants in the Western world are fruits, vegetables (vitamin C, ß-carotene, α-tocopherol), meat and milk (selenium, magnesium, zinc). Children may exclude or eat less of some fruits and vegetables due to cross-reactivity between pollen and these foods, complicating assessment of causal relationships. OBJECTIVE: To investigate the association between dietary antioxidant intake and allergic disease, taking potential reverse causation into account. METHODS: Data on 2442 8-year-old children from the Swedish birth cohort study BAMSE were analysed. Children with completed parental questionnaires on exposures and health, including a food-frequency questionnaire and who provided a blood sample were included. Associations between antioxidant intake during the past year and current allergic disease were analysed using logistic regression. RESULTS: An inverse association was observed between intake of ß-carotene and rhinitis (OR(adj), highest vs. lowest quartile, 0.67, 95% CI 0.49-0.93). Magnesium intake was inversely related to asthma (OR(adj), 0.65, 95% CI 0.42-1.00) and atopic sensitisation (OR(adj), 0.78, 95% CI 0.61-1.00). Following exclusion of children who avoided certain fruits, vegetables or milk due to allergic symptoms (n = 285), the inverse association remained between magnesium intake and asthma (OR(adj), 0.58, 95% CI 0.35-0.98), whereas all other associations became non-significant. CONCLUSION AND CLINICAL RELEVANCE: Diet modifications due to allergy may affect the antioxidant intake and needs to be considered when investigating the relationship between diet and allergic disease. Magnesium intake seems to have a protective effect on childhood asthma.

Smoking and the risk of diverticular disease in women.

BACKGROUND: The relationship between smoking and the risk of diverticular disease is unclear. An observational cohort study was undertaken to investigate the association between smoking and diverticular disease. METHODS: Women in the Swedish Mammography Cohort born between 1914 and 1948 were followed from 1997 to 2008. Information on smoking and other lifestyle factors was collected through questionnaires. Patients with symptomatic diverticular disease were identified from Swedish national registers. Relative risks (RRs) of symptomatic diverticular disease (resulting in hospital admission or death) according to smoking status were estimated using Cox proportional hazards models. RESULTS: Of 35 809 women included in the study, 561 (1·6 per cent) had symptomatic diverticular disease. In multivariable analysis, current smokers had an increased risk of symptomatic diverticular disease compared with non-smokers after adjustment for age, intake of dietary fibre, diabetes, hypertension, use of acetylsalicylic acid, non-steroidal anti-inflammatory drugs or steroid medication, alcohol consumption, body mass index, physical activity and level of education (RR 1·23, 95 per cent confidence interval 0·99 to 1·52). Past smokers also had an increased risk (RR 1·26, 1·02 to 1·56). Smokers had a higher risk of developing a diverticular perforation/abscess than non-smokers (RR 1·89, 1·15 to 3·10). CONCLUSION: Smoking is associated with symptomatic diverticular disease.

Confirmed hypertension and plasma 25(OH)D concentrations amongst elderly men.

OBJECTIVES: the results of experimental studies suggest that vitamin D deficiency activates the renin-angiotensin system and predisposes to hypertension. Results of previous epidemiological studies investigating the association between 25-hydroxyvitamin D [25(OH)D] status and hypertension have not been consistent, perhaps because of their sole reliance on office blood pressure (BP) measurements leading to some misclassification of hypertension status. No previous studies have examined the association between 25(OH)D status and confirmed hypertension assessed with both office and 24-h BP measurements. DESIGN: in this cross-sectional study, we investigated 833 Caucasian men, aged 71 ± 0.6 years, to determine the association between plasma 25(OH)D concentrations, measured with high-pressure liquid chromatography mass spectrometry, and the prevalence of hypertension. We used both supine office and 24-h BP measurements for classifying participants as normotensive or confirmed hypertensive; participants with inconsistent classifications were excluded. RESULTS: in a multivariable adjusted logistic regression model, men with 25(OH)D concentrations <37.5 nmol L(-1) had a 3-fold higher prevalence of confirmed hypertension compared to those with ≥ 37.5 nmol L(-1) 25(OH)D (odds ratio = 3.3, 95% CI: 1.0-11.0). CONCLUSIONS: our results show that low plasma 25(OH)D concentration is associated with a higher prevalence of confirmed hypertension.

Diet quality and mortality: a population-based prospective study of men.

BACKGROUND/OBJECTIVES: To study quality of diet in relation to all-cause mortality, cardiovascular disease (CVD) and cancer mortality. SUBJECTS/METHODS: The population-based prospective Cohort of Swedish Men (COSM) included 40 837 men, 45-79 years of age, who filled in a FFQ (96 food items) and were CVD- and cancer-free at baseline. Quality of diet was assessed by Recommended Food Score (RFS) based on 36 items and Non-Recommended Food Score (Non-RFS) based on 16 items. Cox's proportional hazards regression models were used to estimate the hazard ratios (HRs) of mortality and 95% confidence intervals (CIs). Multivariate HRs for RFS and Non-RFS were adjusted for age, education, physical activity, martial status, self-perceived health status, smoking status, dietary supplements use, WHR, alcohol use, intake of energy and mutually adjusted. RESULTS: Between 1998 and 2005, 4501 deaths from all-causes were registered. Between 1998 and 2003, there were 1394 CVD and 759 cancer deaths. High RFS (> or =28) compared with low (< or =20) was associated with lower risk of all-cause mortality (HR: 0.81; 95% CI: 0.71-0.91; P-value for trend<0.0001) and CVD mortality (HR: 0.71; 95% CI: 0.54-0.93; P-value for trend=0.003). In contrast, men with high Non-RFS (> or =5) had higher risk of all-cause (HR: 1.21; 95% CI: 1.09-1.34; P-value for trend=0.001) and CVD mortality (HR: 1.27; 95% CI: 1.05-1.54; P-value for trend=0.07) compared to those with low Non-RFS (< or =2 items). No significant associations with cancer mortality were observed. CONCLUSIONS: Both measures of diet quality, RFS and Non-RFS, showed statistically significant associations with all-cause and CVD mortality (recommended foods inversely while nonrecommended foods positively), but not with cancer mortality.

The risk for cutaneous malignant melanoma, melanoma in situ and intraocular malignant melanoma in relation to tobacco use and body mass index.

BACKGROUND: The incidence of cutaneous malignant melanoma (CMM) and melanoma in situ (MIS) has been increasing during the last 50 years. Malignant melanoma (MM) is also the most common intraocular malignancy (IMM). Besides ultraviolet radiation, the cause of these tumours is largely unknown. OBJECTIVES: We designed a study to examine the effect of body mass index (BMI) and tobacco use on the risk for MM and MIS. METHODS: Analyses were performed on a nationwide cohort of 339 802 Swedish construction workers. Exposure information was collected prospectively by questionnaires combined with personal interviews. RESULTS: Follow up yielded a total of 7 663 400 person-years during which 1639 workers developed MM/MIS. The risk for MM/MIS was reduced in current or previous smokers compared with those who had never smoked, both when analysing all smoking tobacco products combined and when analysing cigarette and pipe smokers separately. The risk was further diminished with longer duration of smoking and greater quantity of tobacco smoked. The effect was more evident in CMM/MIS than in IMM. Snuff taking conferred a decreased risk for CMM/MIS, and a BMI over normal weight range conferred an increased risk for CMM. CONCLUSIONS: Tobacco smoking was found to be inversely associated with the risk for CMM and MIS. The mechanism of action is unknown but it has been suggested to be due to the immune suppressive effect that tobacco exerts which would be protective against deleterious immune reactions caused by, for example, the sun. Neither is the mechanism behind the higher risk for CMM due to being overweight known. One hypothesis is that it is an effect of a hormonal imbalance. Further studies are required to elucidate these mechanisms.

Overall obesity, abdominal adiposity, diabetes and cigarette smoking in relation to the risk of pancreatic cancer in two Swedish population-based cohorts.

We examined the associations of body mass index (BMI), waist circumference, a history of diabetes, and cigarette smoking with risk of pancreatic cancer among 37,147 women and 45,906 men followed up during 560,666 person-years in the Swedish Mammography Cohort and the Cohort of Swedish Men; 136 incident cases of pancreatic cancer were diagnosed. The multivariate rate ratio (RR) of pancreatic cancer for obese women and men (BMI > or =30 kg/m(2)) was 1.81 (95% CI: 1.04-3.15) compared to those with a BMI of 20-25 kg/m(2). For a difference of 20 cm (about two standard deviations) in waist circumference, the multivariate RRs were 1.32 (95% CI: 0.73-2.37) among women and 1.74 (95% CI: 1.00-3.01) among men. Pancreatic cancer risk was associated with history of diabetes (multivariate RR: 1.88; 95% CI: 1.09-3.26) and cigarette smoking (multivariate RR for current compared with never smokers: 3.06; 95% CI: 1.99-4.72). Current smokers of > or =40 pack-years had a five-fold elevated risk compared with never smokers. Risk among past smokers approached the RR for never smokers within 5-10 years following smoking cessation. Findings from this prospective study support positive relationships of overall obesity, abdominal adiposity, diabetes and smoking with risk of pancreatic cancer.

Arc and resistance welding and tumours of the endocrine glands: a Swedish case-control study with focus on extremely low frequency magnetic fields.

BACKGROUND: Mechanisms for potential effects of extremely low frequency (ELF) magnetic fields on carcinogenesis have not been identified. A potential pathway could be an interaction with the endocrine system. AIMS: To analyse occupational exposure to ELF magnetic fields from welding, and tumours of the endocrine glands. METHODS: This case-control study was based on a cohort with an increased prevalence of high exposed individuals. A total of 174 incident cases of tumours of the endocrine glands, 1985-94, were identified and data were obtained from 140 (80%) of these cases; 1692 controls frequency matched on sex and age were selected, and information on 1306 (77%) individuals was obtained. A short questionnaire was sent to a work administrator at the workplaces of the cases and controls. The exposure assessment was based on questions about job tasks, exposure to different types of welding, and exposure to solvents. RESULTS: There was an overall increased risk for all tumours of the endocrine glands for individuals who had been welding sometime during the follow up. The increased risk was attributable to arc welding; for resistance welding there was no clear evidence of an association. We found an increased risk for the adrenal glands in relation to arc welding, and for the parathyroid glands in relation to both arc welding and resistance welding. An imprecise increase in risk was also noted for tumours of the pituitary gland for arc welding. No confounding effect was found for solvent exposure, and there was no sign of biological interaction. CONCLUSION: The increased risks of endocrine gland tumours related to welding might be explained by exposure to high levels of ELF magnetic fields.

[Bioartificial materials in urology]. / Bioartifizielle Materialien in der Urologie.

The scope of our research is the development of polymer-based bioabsorbable stents for urologic applications and in vitro testing of tissue reactions of cultured ureteral and urethral segments induced by implanted polymer stent prototypes. For these purposes a tissue cultivation model was developed using selected techniques of tissue engineering. Essential advantages of degradable over nondegradable urethral stents are elimination of the adverse extraction of epithelialized stents and the potential for recovery of organ-specific functionality. Moreover, the biocompatibility of a degradable urethral stent could potentially reduce the risk of restenosis due to hyperplasia and could be used, even repeatedly, for the treatment of a number of subvesical obstructions. For the treatment of tumor-induced strictures, application of degradable polymer stents coated with cytostatic drugs may be possible. The mechanical effect of the drug-loaded stent as a "place holder" could be complemented by adjuvant or palliative approaches such as local chemotherapy. We have developed and tested in vitro a degradable urethral stent incorporated with the model drug methotrexate for local drug delivery (LDD) by diffusion and during stent degradation.

Cancer incidence and magnetic field exposure in industries using resistance welding in Sweden.

AIMS: To investigate cancer incidence in workers exposed to high levels of extremely low frequency magnetic fields (ELF-MF). METHODS: A cohort based on the engineering industry was established. Industries assumed to use resistance welding in production were chosen in order to increase the prevalence of high exposed subjects and to reduce the influence of confounding factors. All men and women employed in these branches during 1985-94 were selected, 537 692 men and 180 529 women. Occupation, based on census information from 1980, 1985, and 1990, was linked to a job exposure matrix on ELF-MF. Four exposure groups were used by stratifying on mean workday ELF-MF exposure, using the lowest exposure group as reference. Cancer incidence was obtained by linkage to the Swedish Cancer Registry. RESULTS: Men in the very high exposure group showed an increased incidence of tumours of the kidney, pituitary gland, and biliary passages and liver; for these cancer sites an exposure-response relation was indicated. Women in the very high exposure group showed an increased incidence of astrocytoma I-IV, with a clear exposure-response pattern. An association was suggested in the high exposure group only, for cancer of the corpus uteri and multiple myeloma. Decreased risks in the very high exposure group among men were found for cancer of the colon and connective tissue/muscle. CONCLUSIONS: The results on cancer of the liver, kidney, and pituitary gland among men are in accordance with previous observations. Regarding brain tumours and leukaemia, the outcome for women provided further support of an association. The hypothesis of a biological mechanism involving the endocrine system was partly supported.

Occupational sunlight exposure and cancer incidence among Swedish construction workers.

We studied sunlight exposure from outdoor work in relation to cancer, using data from 323,860 men participating in an occupational health service program of the Swedish construction industry. An experienced industrial hygienist assessed the exposure for 200 job tasks. We estimated relative risks (RRs) adjusted for age, smoking, and magnetic field exposure. There was an increased RR in the high-exposure group for myeloid leukemia [RR = 2.0, 95% confidence interval (95% CI) = 1.1-3.6] and lymphocytic leukemia (RR = 1.7, 95% CI = 0.9-3.2). For non-Hodgkin's lymphoma there was a 30% increase in risk in the high-exposure group (95% CI = 0.9-1.9). There was no increased risk of malignant melanoma, except for tumors of the head, face, and neck in the high-exposure group (RR = 2.0, 95% CI = 0.8-5.2), and we also found an increased risk for malignant melanoma of the eye in this group (RR = 3.4, 95% CI = 1.1-10.5). Outdoor workers had no increased risk of nonmelanoma skin cancer. Nevertheless, the RR for lip cancer (squamous cell carcinoma) among the high-exposure group was estimated at 1.8 (95% CI = 0.8-3.7). Among other sites, an increased risk of stomach cancer was suggested in this group (RR = 1.4, 95% CI = 1.0-1.9). The results for lymphoma, leukemia, and possibly also for stomach cancer might reflect a suppression of the immune system from ultraviolet light in outdoor workers.