ISSN:1044-3983    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:1044-3983    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:1044-3983    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background:Exposure to electromagnetic fields (EMF) has been hypothesized to increase the risk of breast cancer by inhibiting the normal nocturnal rise in melatonin levels.Methods:Information on electric blanket use was collected in a large, 2-stage, population-based, case-control investigation of breast cancer, The Long Island Breast Cancer Study Project (LIBCSP) and the EMF and Breast Cancer on Long Island Study (EBCLIS). The LIBCSP used a comprehensive questionnaire, including questions about electric appliance use, with responses available on 1354 cases diagnosed between mid-1996 and mid-1997 and 1426 control subjects. EBCLIS enrolled 576 cases and 585 control subjects who had participated in the LIBCSP and who had lived in their current homes for at least 15 years. EBCLIS participants were interviewed to obtain additional information on EMF exposures, including detailed questions on electric blanket use.Results:Analyses of both the EBCLIS and the LIBCSP groups showed no association with breast cancer for ever-use of electric blankets, current or former use, use directly on the body, or use throughout the night in either pre- or postmenopausal women (range of adjusted odds ratios for ever vs. never use: 0.9-1.2). Furthermore, there was no trend in risk with increased duration of use, frequency of use, or other indicators of more intense exposure to EMF. Electric blanket use was not associated with hormone receptor status of the tumor.Conclusions:The results of this large investigation are consistent with those of most previous studies, and do not support the hypothesis that electric blanket use is associated with increased breast cancer risk.

ISSN:1044-3983    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background:Suspended particles and ozone have been associated with varying degrees of cardiac autonomic dysfunctionMethods:In Mexico City, residents from a nursing home underwent heart rate variability analysis every other day for 3 months. Indoor and outdoor PM2.5(particulate matter less than 2.5 mm in diameter) were measured daily at the nursing home. Levels of ozone and other atmospheric pollutants were obtained from a nearby automated monitoring station.Results:Of the initial 42 screened participants, 34 (81%) were followed during the study period. The 24-hour average levels of indoor PM2.5ranged from 15 to 67 &mgr;g/m3, and outdoor PM2.5ranged from 9 to 87 &mgr;g/m3. Daily 1-hour maximum ozone levels ranged from 47 to 228 ppb. After adjusting for age and heart rate, we observed a strong decrease in the high frequency component of heart rate variability and the average 24-hour concentrations of PM2.5. Participants with hypertension had considerably larger reductions in their HF-HRV (high frequency–heart rate variability) component in relation to both ozone and PM2.5exposure.Conclusions:Our results suggest that ambient levels of PM2.5and ozone can reduce the high-frequency component of heart rate variability in elderly subjects living in Mexico City and that subjects with underlying hypertension are particularly susceptible to this effect.

ISSN:1044-3983    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background:Daily air pollution is associated with increased hospital admissions for cardiovascular diseases, but there are few observations on the link with acute myocardial infarction. To evaluate the relation between various urban air pollutants (total suspended particulate, SO2, CO, NO2) and hospital admissions for acute myocardial infarction in Rome, Italy, we performed a case-crossover analysis and studied whether individual characteristics act as effect modifiers.Methods:We studied 6531 subjects residing in Rome and hospitalized for a first episode of acute myocardial infarction (International Classification of Diseases, 9thedition: 410) from January 1995 to June 1997. The following individual information was available: sex, age, date of hospitalization, coexisting illnesses (hypertension, 25%; diabetes, 15%), and cardiac severity (conduction disorders, 6%; cardiac dysrhythmias, 20%; heart failure, 11%). Daily air pollution data were taken from 5 city monitors. We used a time-stratified case-crossover design; control days were the same day of the week as the myocardial infarction occurred, in other weeks of the month.Results:Positive associations were found for total suspended particulate, NO2and CO. The strongest and most consistent effect was found for total suspended particulate. The odds ratio (OR) associated with 10 &mgr;g/m3of total suspended particulate over the 0- to 2-day lag was 1.028 (95% confidence interval [CI] = 1.005–1.052). The association with total suspended particulate tended to be stronger among people older than 74 years of age (OR = 1.046; CI = 1.005–1.089), in the warm period of the year (OR = 1.046; CI = 1.008–1.087), and among subjects who had heart conduction disorders (OR = 1.080; CI = 0.987–1.181).Conclusions:The results suggest that air pollution increases the risk of myocardial infarction, especially during the warm season. There was a tendency for a stronger effect among the elderly and people with heart conduction disturbances.

ISSN:1044-3983    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background:A unique, active, timely, low-cost surveillance system for the metropolitan area of Mexico City was established in the mid-1990s.Methods:The system obtained upper and lower respiratory tract symptoms and eye symptoms from daily interviews for a systematic sample of the general nonhospitalized population living within a 2-km radius of air pollution monitors during 1996-1997.Results:Ozone increments (10 ppb) were associated with upper respiratory symptoms (odds ratio [OR] = 1.003; 95% confidence interval [CI] = 1.002-1.004) and ocular symptoms indicators (OR = 1.005; CI = 1.004-1.007), and with a higher risk of lower respiratory symptoms indicator among nonsmokers (OR = 1.003; CI = 1.002-1.005). Increases in relative humidity reduced the risk of increments of sulfur dioxide on the 3 acute health indicators. Association of PM10with health indicators varied among the 5 regions. During emergency episodes, symptoms increased sharply when ozone reached 281 ppb, a finding that resulted in a change in the ozone criteria for emergency declaration from 294 to 281 ppb.Conclusions:This system has been low cost, timely, and useful for local decision making.

ISSN:1044-3983    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background:GSTP1is a gene that helps detoxify foreign substances in the body. Functional polymorphisms ofGSTP1have been studied as risk factors for lung cancer. Past studies have compared the effect of the “at risk” polymorphism in two strata of smoking pack-years (usually defined by the median among controls). We examined the interaction betweenGSTP1polymorphisms and cumulative exposure to smoking and their association with lung cancer risk.Methods:Data are from a large hospital-based case–control study of persons treated for primary lung cancer at the Massachusetts General Hospital since 1992. Controls were drawn from friends and nonrelated family members. We genotyped 1,042 cases and 1,161 controls forGSTP1using polymerase chain reaction–restriction fragment length polymorphism techniques.Findings:TheGSTP1 GGgenotype approximately doubled the lung cancer risk associated with pack-years. This interaction was stronger among current smokers. At 26 pack-years (median among controls with a smoking history), the adjusted odds ratio for the association between pack-years and lung cancer risk was 13 (95% confidence interval = 6.5–25) among current smokers with theGSTP1 GGgenotype compared with 6.1 (95% confidence interval = 4.9–7.5) among those with theGSTP1 AAgenotypeConclusions:GSTP1 GGincreases the lung cancer risk associated with pack-years of smoking.

ISSN:1044-3983    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background:It is well established that the incidence rates of first primary breast cancer have been increasing over time. In contrast, the incidence rates of second primary breast cancer are largely undocumented. This study describes the epidemiology of second primary breast cancer among a population-based cohort of 305,533 U.S. women diagnosed with breast cancer between 1973 and 1998Methods:We compared age-specific incidence rates for overall and second primary breast cancer according to year of diagnosis and demographic and tumor characteristicsResults:Overall, age-specific rates of breast cancer increased with increasing age and year of diagnosis, whereas incidence of second primary breast cancer peaked among young women and declined after 1988. Consistent with what is known about genetic susceptibility to breast cancer, at every age the rate of second primaries was greater than the overall rate; among women age 20 to 29 years the rate of second primary was more than 100 times greater. Although overall age-specific rates of breast cancer for African-American women were lower than for whites, rates of second primaries were higher. Women with a first primary that was either lobular or medullary had a greater likelihood of developing a second primary, although, there were relatively few with these histologic typesConclusions:The pattern of incidence rates for first and second primary breast cancer differ markedly over time and by age.

ISSN:1044-3983    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background:There is suggestive evidence that residential radon increases lung cancer risk. To elucidate this association further, we conducted a case-control study in Thuringia and Saxony in Eastern Germany during 1990-1997.Methods:Histologically confirmed lung cancer patients from hospitals and a random sample of population controls matched on age, sex and geographical area were personally interviewed with respect to residential history, smoking, and other risk factors. One-year radon measurements were performed in houses occupied during the 5-35 years prior to the interview. The final analysis included a total of 1,192 cases and 1,640 controls. Odds ratios (OR) and 95% confidence intervals (CI) were estimated by logistic regression.Results:Measurements covered on average 72% of the exposure time window, with mean radon concentrations of 76 Bq/m3among the cases and 74 Bq/m3among the controls. The smoking- and asbestos-adjusted ORs for categories of radon (50-80, 80-140 and >140 Bq/m*3, compared with 0-50 Bq/m3) were 0.95 (CI = 0.77 to 1.18), 1.13 (CI = 0.86 to1.50) and 1.30 (CI = 0.88 to 1.93). The excess relative risk per 100 Bq/mł was 0.08 (CI = −0.03 to 0.20) for all subjects and 0.09 (CI = −0.06 to 0.27) for subjects with complete measurements for all 30 years.Conclusions:Our data indicate a small increase in lung cancer risk as a result of residential radon that is consistent with the findings of previous indoor radon and miner studies.

ISSN:1044-3983    

出版商:OVID    

年代:2003

数据来源: OVID