Biomedical subjects

Martine Hours

Publications and source records attributed to Martine Hours.

9 recordsLinked to original sources

PubMed2006

Case-control study on renal cell cancer and occupational exposure to trichloroethylene. Part II: Epidemiological aspects.

To test the effect of the exposure to trichloroethylene (TCE) on renal cell cancer (RCC) risk, a case-control study was performed in the Arve Valley (France), a geographic area with a high frequency and a high degree of such exposure. Cases and controls were selected from various sources: local general practitioners and urologists practicing in the area and physicians (urologists and oncologists) from other hospitals of the region who might treat patients from this area. Blinded telephone interviews with cases and controls were administered by a single trained interviewer using occupational and medical questionnaires. The analysis concerned 86 cases and 316 controls matched for age and gender. Three approaches were developed to assess the link between TCE exposure and RCC: exposure to TCE for at least one job period (minimum 1 year), cumulative dose (number of p.p.m. of TCE per job period multiplied by the number of years in the job period) and the effect of exposure to peaks. Multivariate analysis was performed taking into account potential confounding factors. Allowing for tobacco smoking and Body Mass Index, a significantly 2-fold increased risk was identified for high cumulative doses: odds ratio (OR)=2.16 (1.02-4.60). A dose-response relationship was identified, as was a peak effect; the adjusted OR for highest class of exposure-plus-peak being 2.73 (1.06-7.07). After adjusting for exposure to cutting fluids the ORs, although still high, were not significant because of lack of power. This study suggests an association between exposures to high levels of TCE and increased risk of RCC. Further epidemiological studies are necessary to analyze the effect of lower levels of exposure.

Aged↗

PubMed2006

Case-control study on renal cell cancer and occupational exposure to trichloroethylene. Part I: Exposure assessment.

A method for a semi-quantitative retrospective assessment of exposure to trichloroethylene (TCE) was implemented for a case-control study conducted in the Arve valley (France), an area with a widely developed screw-cutting industry, where teams of occupational physicians have collected a large quantity of well-documented measurements. A task-exposure matrix was developed to link the main working circumstances in a screw-cutting workshop to corresponding TCE-exposure levels: a 'basic level' was assigned to each task, standing for usual working procedures; exposure circumstances, such as duration or distance from the TCE source, were introduced as corrective factors. In parallel, a detailed occupational questionnaire was designed, setting subjects' descriptions of their successive jobs and working circumstances against levels assessed in the matrix. Possible exposure to TCE, plus some other occupational compounds (other solvents, oils, some metals, asbestos, welding fumes and ionizing radiations), were assessed for any job in all job histories. An average level of exposure to TCE, related to an 8 h usual working day, was attributed to each job period in turn, which was then categorized into six classes: 0; 1-35; 35-50; 50-75; 75-100; and >100 p.p.m. A total of 402 study subjects described their occupational life (average 3.7 jobs/subject, from 1924 to 2003). About 19% of the 1486 job periods described were assessed as being exposed to TCE; of these, 72.2% involved levels<35 p.p.m., 13.2% involved levels>50 p.p.m. and 5.4% above the French occupational exposure limit of 75 p.p.m. (TWA 8 h). A total of 41 job periods included exposure with peaks. Compared with levels encountered in other studies, the more severely exposed part of our study population seemed more exposed than most other populations previously studied, owing to vapor degreasing practices.

Carcinogens↗

PubMed2006

A pooled analysis of bladder cancer case-control studies evaluating smoking in men and women.

OBJECTIVE: A recent study suggested that risk of bladder cancer may be higher in women than in men who smoked comparable amounts of cigarettes. We pooled primary data from 14 case-control studies of bladder cancer from Europe and North America and evaluated differences in risk of smoking by gender. METHODS: The pooled analysis included 8316 cases (21% women) and 17,406 controls (28% women) aged 30-79 years. Odds ratios (ORs) and 95% confidence intervals (95% CI) for smoking were adjusted for age and study. Exposure-response was evaluated in a stratified analysis by gender and by generalized additive models. RESULTS: The odds ratios for current smokers compared to nonsmokers were 3.9 (95% CI 3.5-4.3) for males and 3.6 (3.1-4.1) for females. In 11 out of 14 studies, ORs were slightly higher in men. ORs for current smoking were similar for men (OR = 3.4) and women (OR = 3.7) in North America, while in Europe men (OR = 5.3) had higher ORs than women (OR = 3.9). ORs increased with duration and intensity in both genders and the exposure-response patterns were remarkably similar between genders. CONCLUSION: These results do not support the hypothesis that women have a higher relative risk of smoking-related bladder cancer than men.

Adult↗

PubMed2004

Respiratory function among waste incinerator workers.

INTRODUCTION: Whereas air pollutants have been measured in incinerator working areas, few studies have focused on the effects of these pollutants on the lung function of incinerator workers. In France, a study was performed among workers at two urban incinerators, aimed at identifying a link between exposure to different pollutants in incinerator plants and respiratory lung function impairments. METHODS: A follow-up of lung function was carried out on 83 incinerator workers from two incinerator plants, comparing them with a group of 76 non-exposed workers recruited by the same occupational physician. Workers' lung functions were measured during their yearly occupational medical examination, for 3 years. The American Thoracic Society quality criteria were used to control the quality of the flow-volume curves. RESULTS: Base-line lung functions were lower among incinerator workers than among non-exposed workers. The few significant differences were indicative of obstructive symptoms. During the first year the differences observed between the two groups were close to the significant threshold value of 5% for FEF(75)/ PV and FEF(25-75)/PV. During the third year significant differences covered three parameters: FEF(50)/PV, FEF(25-75)/PV and FEF(25-75)/FVC. After smoking habits (pack-years), medical history of allergy or lung diseases and the examination centres had been taken into account in a linear regression, the reduction of FEF(75)/PV in the first year and FEF(25-75)/FVC in the third year was linked to exposure in incinerator plants. There was no significant association between exposure and the differences observed in the FEF(25-75)/PV in the first year or in the FEF(50)/PV and the FEF(25-75)/PV in the third year. CONCLUSION: This analysis of incinerator workers' lung functions has identified some lung impairments among workers exposed to incinerator air pollutants compared to non-exposed workers, thus indicating possible obstructive disorders among incinerator workers. However, these impairments are moderate and in accordance with the low levels of airborne pollutants identified in a previous study.

Adult↗

PubMed2004

Pregnancy and multiple sclerosis (the PRIMS study): clinical predictors of post-partum relapse.

The influence of pregnancy in multiple sclerosis has been a matter of controversy for a long time. The Pregnancy in Multiple Sclerosis (PRIMS) study was the first large prospective study which aimed to assess the possible influence of pregnancy and delivery on the clinical course of multiple sclerosis. We report here the 2-year post-partum follow-up and an analysis of clinical factors which might predict the likelihood of a relapse in the 3 months after delivery. The relapse rate in each trimester up to the end of the second year post-partum was compared with that in the pre-pregnancy year. Clinical predictors of the presence or absence of a post-partum relapse were analysed by logistic regression analysis. Using the best multivariate model, women were classified as having or not having a post-partum relapse predicted, and this was compared with the observed outcome. The results showed that, compared with the pre-pregnancy year, there was a reduction in the relapse rate during pregnancy, most marked in the third trimester, and a marked increase in the first 3 months after delivery. Thereafter, from the second trimester onwards and for the following 21 months, the annualized relapse rate fell slightly but did not differ significantly from the relapse rate recorded in the pre-pregnancy year. Despite the increased risk for the 3 months post-partum, 72% of the women did not experience any relapse during this period. Confirmed disability continued to progress steadily during the study period. Three indices, an increased relapse rate in the pre-pregnancy year, an increased relapse rate during pregnancy and a higher DSS (Kurtzke's Disability Status Scale) score at pregnancy onset, significantly correlated with the occurrence of a post-partum relapse. Neither epidural analgesia nor breast-feeding was predictive. When comparing the predicted and observed status, however, only 72% of the women were correctly classified by the multivariate model. In conclusion, the results for the second year post-partum confirm that the relapse rate remains similar to that of the pre-pregnancy year, after an increase in the first trimester following delivery. Women with greater disease activity in the year before pregnancy and during pregnancy have a higher risk of relapse in the post- partum 3 months. This is, however, not sufficient to identify in advance women with multiple sclerosis who are more likely to relapse, especially for planning therapeutic trials aiming to prevent post-partum relapses.

Adult↗

PubMed2004

Systemic sclerosis and occupational risk factors: role of solvents and cleaning products.

OBJECTIVE: To analyze occupational and non-occupational exposure factors suspected of being associated with scleroderma (SSc), with a view to inculpating or excluding certain potentially toxic substances (e.g., solvents), thereby contributing to the recognition of such toxins in the field of occupational health. METHODS: The study comprised 10 men and 83 women diagnosed with SSc between 1995 and 1999 (American College of Rheumatology criteria) and early SSc, and 206 age and sex matched controls. The SSc registry is all-inclusive in the French administrative departments of Isere and Savoie so controls were randomly selected from the general population (using telephone directories) in these departments to ensure full representation. Exposure factors were analyzed for each subject by a personal questionnaire, and an individual evaluation was carried out by an industrial expert. Data were analyzed by conditional logistical regression adjusting for educational level. RESULTS: Construction workers were at significantly higher risk of contracting SSc; odds ratio (OR) = 4.01 (95% confidence interval 1.14-14.09). Analysis by industrial experts identified exposure to certain toxic substances regularly used by these same workers as risk factors for SSc: cleaning products: OR = 1.66 (0.90-3.08) (both sexes) and OR = 1.71 (0.92-3.20) (women only); solvents: OR = 3.23 (1.58-6.63) (both sexes) and OR = 2.80 (1.28-6.11) (women only); synthetic adhesives: OR 25.36 (1.36-472.28) (on 3 exposed cases). CONCLUSION: Exposure to either cleaning products or solvents emerged as a risk factor for SSc. Exposure factors should be characterized and results of all studies compared to implement appropriate preventive measures in relevant workplaces.

Adult↗

PubMed2003

Morbidity among municipal waste incinerator workers: a cross-sectional study.

OBJECTIVES: In order that the occupational exposures and health risks for municipal waste incinerator operators be better determined, a study was carried out in three centres. METHODS: A transversal study was carried out for 102 male incinerator workers matched for age with 94 male workers from other industrial activities. Three groups of exposed workers were considered (group 1: "crane operators" and "equipment operators"; group 2: "furnace " workers; group 3: "maintenance" and "effluent-treatment" workers). Data were collected through a questionnaire and medical examination. The respiratory function was explored and blood samples were taken for biological analysis. Statistical analysis using chi(2) or Student's test, and calculation of odds-ratio (OR) using logistic regression analysis were performed. RESULTS: There were no significant differences in general symptoms between the two groups. Skin symptoms (OR =4.85; 2.04-11.51 for the "maintenance and effluent" workers) were more often observed in the exposed group. An excess of respiratory problems was also encountered: daily coughing ["maintenance and effluent" groups (OR =2.55; 0.84-7.75); "furnace men" (OR =6.58; 2.18-19.85)]. A significant relationship between exposure and the decrease of several pulmonary parameters was observed. The liver and haematological tests were well within the normal range; nevertheless, a slight but significant increase in the white blood cells was observed in the exposed group. Higher blood lead levels were found for exposed workers. CONCLUSION: There were few adverse health effects in our morbidity study but skin irritation and cough were more frequent in the exposed workers. A slight decrease in pulmonary function was observed. These findings are in agreement with those of several other studies.

Accidents, Occupational↗

PubMed2003

Occupation and bladder cancer among men in Western Europe.

OBJECTIVES: We examined which occupations and industries are currently at high risk for bladder cancer in men. METHODS: We combined data from 11 case-control studies conducted between 1976-1996 in six European countries. The study comprised 3346 incident cases and 6840 controls, aged 30-79 years. Lifetime occupational and smoking histories were examined using common coding. RESULTS: Odds ratios for eight a priori defined high-risk occupations were low, and with the exception of metal workers and machinists (OR = 1.16, 95% CI = 1.02-1.32), were not statistically significant. Higher risks were observed for specific categories of painters, metal, textile and electrical workers, for miners, transport operators, excavating-machine operators, and also for non-industrial workers such as concierges and janitors. Industries entailing a high risk included salt mining, manufacture of carpets, paints, plastics and industrial chemicals. An increased risk was found for exposure to PAHs (OR for highest exposure tertile = 1.23, 95% CI = 1.07-1.4). The risk attributable to occupation ranged from 4.2 to 7.4%, with an estimated 4.3% for exposure to PAHs. CONCLUSIONS: Metal workers, machinists, transport equipment operators and miners are among the major occupations contributing to occupational bladder cancer in men in Western Europe. In this population one in 10 to one in 20 cancers of the bladder can be attributed to occupation.

Adult↗

PubMed2003

Comparison of measurement strategies for prospective occupational epidemiology.

In the context of a prospective assessment of exposure for epidemiology, our objective is to obtain an optimal group-based design of allocation of a fixed total number of measurements. Such a design has been described by Ashford [Ashford JR. (1958) The design of a long-term sampling programme to measure the hazard associated with an industrial environment. J R Statist Soc A; 121: 331-47]. As this strategy is not operational, we developed three series of strategies: the first based on simplifications of Ashford's strategy; the second based on a pilot study; and the third on an iterative assessment of the group specific standard deviation of exposure. These strategies are compared by simulating a day-to-day individual exposure in several industrial sites and the resulting health effect. Our criteria for comparing strategies are the mean squared error of the estimated exposure in each group weighted by the number of subjects and the mean squared error of the estimated linear regression coefficient in the dose-response relationship. Strategies relying on an iterative approach have been found to perform best whatever the circumstances, nearly as well as Ashford's optimal strategy.

Humans↗