Cigarette smoking and other risk factors in relation to p53 expression in breast cancer among young women.
(25/7400)
p53 mutations may be a fingerprint for cigarette smoking and other environmental carcinogens, including breast carcinogens. This study was undertaken to explore whether p53 mutations are associated with environmental or other suspected or established risk factors for breast cancer. p53 protein detection by immunohistochemistry (which is more easily quantified in large epidemiological studies than are mutations, and are highly correlated with them) was determined for 378 patients from a case-control study of breast cancer. In this population-based sample of women under the age of 45 years, 44.4% (168/378) of the cases had p53 protein detected by immunohistochemistry (p53+). Polytomous logistic regression was used to calculate the odds ratios (ORs) for p53+ and p53- breast cancer, as compared with the controls, in relation to cigarette smoking and other factors. The ratio of the ORs was used as an indicator of heterogeneity in risk for p53+ versus p53- cancer. The ratio of the ORs in a multivariate model was substantially elevated among women with a greater than high school education [2.39; 95% confidence interval (CI), 1.43-4.00], current cigarette smokers (1.96; 95% CI, 1.10-3.52), and users of electric blankets, water beds, or mattresses (1.78; 95% CI, 1.11-2.86). Nonsignificant heterogeneity was noted for family history of breast cancer and ethnicity but not for other known or suspected risk factors. Coupled with the strong biological plausibility of the association, our data support the hypothesis that in breast cancer, as with other tumors, p53 protein immunohistochemical detection may be associated with exposure to environmental carcinogens such as cigarette smoking. (+info)
Breast cancer risk in monozygotic and dizygotic female twins: a 20-year population-based cohort study in Finland from 1976 to 1995.
(26/7400)
This population-based study investigated the occurrence of breast cancer over a 20-year period in a cohort of monozygotic (MZ) and dizygotic (DZ) twins in Finland. Altogether, 13,176 female twins of known zygosity who were living in Finland at the end of 1975 were identified from the Finnish Twin Cohort Study and followed-up for cancer through the Finnish Cancer Registry for the years 1976-1995. Standardized incidence ratios (SIRs) were calculated, based on national cancer incidence rates. The relative risk of breast cancer for MZ twins compared to DZ twins was decreased [SIR(MZ)/SIR(DZ) ratio = 0.78; 95% confidence interval (CI), 0.58-1.0]; the decreased risk for MZ twins (SIR = 0.76; 95% CI, 0.58-1.0) accounted for this result, whereas the risk for DZ twins did not differ from the general population risk (SIR = 0.98; 95% CI, 0.84-1.1). There was no risk decrease among MZ twins in other cancers related to reproductive behavior; i.e., number of children and age at first birth seem not to explain the decreased risk of breast cancer. Our results, which are in line with earlier studies on the same topic, suggest that prenatal influences or postnatal behavioral factors may protect MZ female twins from breast cancer. (+info)
Volume flow estimation by colour duplex.
(27/7400)
OBJECTIVE: To assess the accuracy of volume blood flow using a digitised colour duplex scanner. DESIGN: Observer-blinded experimental study. MATERIALS AND METHODS: Method comparison was performed with linear regression analysis of 89 paired observations in 11 anaesthetised pigs. A Siemens Sonoline Elegra ultrasound system was used for transcutaneous volume flow estimation using invasive transit time flowmetry by Cardiomed as a reference. RESULTS: For the individual measurement we found a standard error of the estimate (SEE) of 22 ml/min. For the regression line, however, the SEE was only 0.2 ml/min. CONCLUSIONS: Digitised colour-duplex sonography has a volume flow measurement error that is too high for single measurements in the individual patient for the method to be useful in clinical decision making, but sufficient for examinations of groups and comparison of groups. (+info)
Prolonged QT interval predicts cardiac and all-cause mortality in the elderly. The Rotterdam Study.
(28/7400)
AIMS: To examine the association between heart-rate corrected QT prolongation and cardiac and all-cause mortality in the population-based Rotterdam Study among men and women aged 55 years or older and to compare the prognostic value of the QT interval, using different formulas to correct for heart rate. METHODS AND RESULTS: After exclusion of participants with arrhythmias or bundle branch block on the ECG, the study population consisted of 2083 men and 3158 women. The QT interval was computed by the Modular ECG Analysis System (MEANS). Data were analysed using Cox' proportional hazards model. Participants in the highest quartile of the heart-rate corrected QT interval had about a 70% age- and sex-adjusted increased risk for both all-cause mortality (hazard ratio (HR) 1.8; 95% CI:1.3-2.4) and cardiac mortality (HR 1.7; 95% CI:1.0-2.7) compared to those in the lowest quartile. In women, the increased risk associated with prolonged QT for cardiac death was more pronounced than in men. These risk estimates did not change after adjustment for potential confounders, including history of myocardial infarction, hypertension and diabetes mellitus. CONCLUSION: A prolonged heart-rate corrected QT interval is an independent predictor for cardiac and all-cause mortality in older men and women. The risk associated with prolonged QT is hardly affected by the heart-rate correction formula used. (+info)
Factor V Arg506Gln mutation is not associated with cardiovascular mortality in older women.
(29/7400)
Factor V Arg506Gln is the most common genetic risk factor for venous thrombosis and is associated with myocardial infarction in young women, especially among smokers. The authors studied the relation of factor V Arg506Gln to cardiovascular mortality in older women in a prospective cohort study of 12,239 women, living in the city of Utrecht, who were initially aged between 52 and 67 years. Women were followed on vital status between 1976 and 1995 (168,513 years). The factor V Arg506Gln mutation was determined in urine samples of 524 women who died of cardiovascular disease and in a reference group of 517 women who did not. Data were analyzed using a nested case-referent analysis. Factor V Arg506Gln heterozygosity was not associated with the risk of mortality by myocardial infarction, cerebrovascular disease, and other cardiovascular disease, with respective rate ratios and 95% confidence intervals being 1.1 (0.5-2.3), 1.2 (0.5-3.1), and 0.6 (0.2-1.7). No evidence of association was found in subgroups of smokers and age. Factor V Arg506Gln is not a risk factor for cardiovascular mortality in older women. Discrepancies with other studies may be explained by different study populations, as age and sex may modify both the frequency of cardiovascular disease and the effect of its risk factors. (+info)
Estimation of injecting drug users in the City of Edinburgh, Scotland, and number infected with human immunodeficiency virus.
(30/7400)
OBJECTIVES: To estimate (1) the number of current and former injecting drug users (IDU) infected with human immunodeficiency virus (HIV) alive in Edinburgh, and (2) the total number of current injectors in the city. METHODS: The number of infected IDU was estimated using a local register of HIV infections with correction for incompleteness of the register. The number of injectors was estimated by two independent methods, one based on the HIV register, the other by log-linear modelling of four lists of IDU interviewed in a city-wide survey, and/or attending drug treatment agencies and family doctors because of drug use. MAIN OUTCOME MEASURES: Estimates for the period 1992-1994 of number of IDU infected with HIV, total number of IDU, and prevalence of injecting. RESULTS: The HIV register indicated that 371 infected drug users who had ever injected were alive and resident in Edinburgh. In all, 95% of infected survey respondents appeared in the register, leading to a corrected estimate of 472 infected ever injectors. From this the number of IDU currently injecting (i.e. in the previous 6 months) was estimated to be 1770 (95% CI: 1340-2240), and the prevalence of injecting as 8.0 (95% CI: 4.8-10.8) per 1000 Edinburgh residents aged 15-59 years. Log-linear modelling gave an estimate of 2070 (95% CI: 1360-2800) current injectors. CONCLUSIONS: The number of HIV-infected IDU in Edinburgh was estimated to be twice that in the larger nearby city of Glasgow, where a higher proportion of young adults currently injected drugs. Knowledge of the high prevalence of HIV in Edinburgh IDU (19.3%), the prescribing of oral substitutes, and counselling by doctors and drug workers are perceived reasons for the reduction in the prevalence of injecting which has occurred in Edinburgh in recent years. Such measures need to be continued to encourage further reduction of injecting. (+info)
Effects of a drug overdose in a television drama on presentations to hospital for self poisoning: time series and questionnaire study.
(31/7400)
OBJECTIVES: To determine whether a serious paracetamol overdose in the medical television drama Casualty altered the incidence and nature of general hospital presentations for deliberate self poisoning. DESIGN: Interrupted time series analysis of presentations for self poisoning at accident and emergency departments during three week periods before and after the broadcast. Questionnaire responses collected from self poisoning patients during the same periods. SETTING: 49 accident and emergency departments and psychiatric services in United Kingdom collected incidence data; 25 services collected questionnaire data. SUBJECTS: 4403 self poisoning patients; questionnaires completed for 1047. MAIN OUTCOME MEASURES: Change in presentation rates for self poisoning in the three weeks after the broadcast compared with the three weeks before, use of paracetamol and other drugs for self poisoning, and the nature of overdoses in viewers of the broadcast compared with non-viewers. RESULTS: Presentations for self poisoning increased by 17% (95% confidence interval 7% to 28%) in the week after the broadcast and by 9% (0 to 19%) in the second week. Increases in paracetamol overdoses were more marked than increases in non-paracetamol overdoses. Thirty two patients who presented in the week after the broadcast and were interviewed had seen the episode-20% said that it had influenced their decision to take an overdose, and 17% said it had influenced their choice of drug. The use of paracetamol for overdose doubled among viewers of Casualty after the episode (rise of 106%; 28% to 232%). CONCLUSIONS: Broadcast of popular television dramas depicting self poisoning may have a short term influence in terms of increases in hospital presentation for overdose and changes in the choice of drug taken. This raises serious questions about the advisability of the media portraying suicidal behaviour. (+info)
The prevalence of low back pain in adults: a methodological review of the literature.
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The prevalence of low back pain (LBP) has been reported in the literature for different populations. Methodological differences among studies and lack of methodological rigor have made it difficult to draw conclusions from these studies. A systematic review was done for adult community prevalence studies of LBP published from 1981 to 1998. The technique of capture-recapture was performed to estimate the completeness of the search strategy used. Established guidelines and a methodological scoring system were used to critically appraise the studies. Thirteen studies were deemed methodologically acceptable. Differences in the duration of LBP used in the studies appeared to affect the prevalence rates reported and explain much of the variation seen. It was estimated that the point prevalence rate in North America is 5.6%. Further studies using superior methods are needed, however, before this estimate can be used with confidence to make health care policies and decisions relating to physical therapy. (+info)