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Background: The etiologic role of biomechanical factors for low back injury (LBI) needs to be confirmed in prospective studies that control for psychosocial factors. Methods: Complete baseline information on 1,233 vehicle operators was gathered during medical examinations and by questionnaire. First LBI during 7.5 years of follow-up was ascertained from insurance records. Hazard ratios and etiologic fractions were analyzed with Cox regression models stratified by injury severity and controlling for age, sex, height, weight, ethnicity, and biomechanical and psychosocial job factors. Severe LBI was defined as medically diagnosed postlaminectomy syndrome, spinal stenosis, herniated lumbar disc, sciatica, or spinal instability. Results: An exponential dose-response relationship was found between weekly driving hours and incidence of first LBI. Indicators of physical workload were more strongly associated with more severe low back injuries compared to less severe injuries. Rates of severe LBI increased 39% for every 10-hr increase in weekly driving (hazard ratio 1.39, 95% confidence interval 1.15-1.68). Higher risks of severe LBI were also found among operators performing heavy physical labor on cable cars (hazard ratio 2.76, 95% confidence intervals 1.24-614) or reporting more ergonomic problems at baseline HR for upper quartile 1.65 (95% confidence interval 1.08-2.50). Estimates of etiologic fractions suggest that reduction of ergonomic problems to the low level currently experienced by 25% of drivers would result in a 19% reduction of severe LBI among all drivers. A change from full- (more than 30 hr) to part-time driving (20-30 hr) could reduce the number of severe LBI by 59%, although this gain would be reduced to 28% at the company level if injuries expected among additional employees, hired to maintain full service are included. Conclusions: Duration of professional driving and ergonomic problems are independent and preventable risk factors for LBI even after adjustment for psychosocial factors. (C) 2004 Wiley-Liss, Inc.

The article reports on seven cases resembling spontaneous pulmonary alveolar proteinosis (PAP) in nonhuman primates, the captive moustached tamarins (Saguinus mystax). It has found intra-alveolar accumulation of amorphous, amphophilic, periodic acid-Schiff-positive, finely granular to dense material in tamarin lung samples. Numerous, irregularly shaped osmiophilic lamellar bodies in type II pneumocytes were observed in the affected lungs through transmission electron microscopy.

Objective: To determine the effect of comorbidity and stage of disease on 3-year survival in women with primary breast cancer.Design: Longitudinal, observational study.Setting: Metropolitan Detroit.Patients: 936 women ages 40 to 84 years.Measurements: Data on stage of breast cancer, treatment type, and comorbidity were obtained from Metropolitan Detroit Cancer Surveillance System (MDCSS) files and medical records. Personal interviews were the source of information on social and behavioral factors. Vital status and cause of death were obtained from MDCSS files.Results: Patients who had 3 or more of 7 selected comorbid conditions had a 20-fold higher rate of mortality from causes other than breast cancer and a 4-fold higher rate of all-cause mortality when compared with patients who had no comorbid conditions. The effects of comorbidity were independent of age, disease stage, tumor size, histologic type, type of treatment, race, and social and behavioral factors. Moreover, women with severe comorbid conditions had uniformly higher mortality rates, and early diagnosis in these women conferred no survival advantage.Conclusion: Comorbidity in patients with breast cancer appears to be a strong predictor of 3-year survival, independent of the effects of breast cancer stage. This finding suggest that trials assessing the efficacy of screening should routinely include measures of comorbidity. [ABSTRACT FROM AUTHOR]

A 2-year-old, captive-born, male moustached tamarin was subjected to necropsy examination after a fatal head trauma. A solitary, circumscribed, subpleural mass (0.6 cm diameter) was found in the right caudal lung lobe. The mass was diagnosed as a mucinous cystadenoma. Histochemical and immunohistochemical tests were performed to further characterize the tumour. Surfactant proteins A, B, C and D were not found in the neoplastic cells, suggesting that the tumour arose from a non-surfactant-producing alveolar lining cell. Pulmonary mucinous cystadenomas are uncommon benign tumours in man and have not been reported previously in animals., (Published by Elsevier Ltd.)

One hypothesis in the literature on anger and hypertension is that a chronic tendency to suppress anger is an etiological factor in the development of hypertension. The present study assessed the relationship between anger expression and hypertension in a multicultural sample of 1,407 San Francisco bus drivers. Simple and multiple regression analyses revealed no significant differences between suppressed or expressed anger and hypertension. Thus, the results of this study do not support the hypothesis that suppressed anger is an etiological factor in hypertension.

Objectives: To examine child characteristics (age, gender) and child care center environments (socioemotional quality, physical safety) that jointly predict injuries for preschool children., Methods: A two year prospective study of 360 preschool children, ages 2-6 years, was conducted in four urban child care centers. Composite scores for center quality and physical safety were derived from on-site observations, and injury rates were based on teacher reports. Poisson regression analyses examined age, gender, center quality, center safety, and the interactions of gender with quality and safety as predictors of injury incidence over one child year., Results: Age was significantly associated with injury rates, with younger children sustaining higher rates. An interaction between gender and center quality also significantly predicted injury incidence: girls in low quality centers experienced more injuries, while girls in high quality centers sustained fewer injuries than their male peers. Finally, an interaction between gender and center safety showed that girls in high safety centers sustained more injuries than boys, while girls in low safety centers sustained fewer injuries., Conclusions: Injuries occur even in relatively safe environments, suggesting that in child care settings, the socioemotional context may contribute, along with physical safety, to the incidence of injury events. Further, gender specific differences in susceptibility to environmental influences may also affect children's vulnerability and risks of injuries. The prevention of injuries among preschool children may thus require attention to and modifications of both the physical and socioemotional environments of child care.

Background: If alcohol consumption mitigates psychological and physiological aspects of the response to stressors, then alcohol consumption might be elevated for individuals exposed to high occupational stressors. Frequency of work stressors and reaction to those stressors were studied in relation to several alcohol-related outcomes., Methods: During the period 1993-1995, 1979 transit operators underwent medical examinations for commercial driver's license renewal. Questionnaire and interview data concerning occupational stress factors and alcohol-related outcomes were available for 1386 (70.2%) of the operators., Results: A positive association was found between the two job stressor-related measures and each of six alcohol-related outcomes. Of these 12 associations, ten were statistically significant. Individuals experiencing high self-reported frequency of job stressors and a higher perceived severity of those job stressors were more likely to drink and more likely to be heavy drinkers. They reported more consequences of alcohol consumption, reported increased consumption since beginning work as transit drivers, and were more likely to report drinking to deal with work stress. They also drank more, but this effect was not significant for either job stress measure. There was virtually no association between either stressor-related measure and alcohol dependency (CAGE)., Conclusions: Together with other published findings, these results suggest increased alcohol-related outcomes in the presence of work stressors. This conclusion has potential implications for worksite health promotion and job design. Because our findings are cross-sectional, further research is needed to clarify the causal nature of the work stressor-alcohol association. Further research also is needed to clarify the role of individual differences and context.

Objectives: (1) To describe the pattern of injury in preschool-aged children in 4 child care centers as compared with the results of other studies; (2) to compare injury rates by sex, age, and child care center; and (3) to examine environmental and child factors contributing to injury severity., Design: A 2-year cohort study of 362 preschool-aged children attending 4 urban child care centers. Teachers completed standardized injury forms on the type of injury, body location, site of injury, and contributing factors., Results: During the 2 years of the study, 1886 injuries were reported. The mean and median child injury rate was 6 and 4 injuries per 2000 exposure hours (equivalent to 1 full-time child care year), respectively. The majority of injuries (87%) were minor, occurred during free play (81%) and on the playground (74%), and were precipitated by child-related factors (59%), such as being pushed. Boys had significantly higher median injury rates than girls. Age-adjusted injury rates for each child care center were significantly different by center (F3 = 61, P<.001). While moderate to severe injuries were more often precipitated by combinations of child and environmental factors (chi2(4) = 20, P<.001), minor injuries were usually precipitated by child-related factors., Conclusions: Injury data from child care centers are important for identifying common risk factors for frequent or severe injury events and for designing injury prevention programs. More research is needed to identify factors contributing to injuries, such as children's behavior and the child care centers' physical and socioemotional environments.

Objective: There is evidence of an association between occupational stress and alcohol consumption. This study investigates the association between workplace racial discrimination and alcohol consumption in a sample of urban transit operators., Methods: During 1993-1995, after undergoing a medical exam, 1,542 transit operators completed an interview. Depending on the outcome, we used logistic or linear regression models to examine the cross-sectional relationship between discrimination experience and alcohol consumption., Results: Operators who reported discrimination in at least one situation, out of a possible four, were more likely to have had negative life consequences as a result of drinking (adjusted OR = 1.97; 95% CI, 1.20-3.83) and were more likely to be classified as having an alcohol disorder (OR = 1.56 [0.96-2.54]), compared to those who reported no instances of workplace discrimination. Results adjusted simultaneously for age, sex, race/ethnicity, education, income, marital status, and seniority. There was no association between workplace discrimination and heavy drinking or drinks per month., Conclusions: Cross-sectional data from a sample of urban transit operators indicates an association between workplace racial discrimination and some measures of alcohol consumption.

Objective: A growing body of literature is documenting the health effects of racial discrimination. The authors investigated the association between racial discrimination and alcohol-related behavior in a sample of urban transit operators., Methods: Using data from a 1993-1995 cross-sectional study of transit operators in San Francisco, California, the authors analyzed responses to two sets of questions about racial discrimination; the first set focused on reaction to unfair treatment and the second on arenas, or domains, of discrimination. Alcohol-related variables were: number of drinks per month, heavy drinking, alcohol dependence, and negative consequences of alcohol consumption., Results: Operators who reported five or more domains of discrimination drank an average of 13.4 more drinks per month than those who reported no domains of discrimination (P = 0.01). Similarly, they were more likely to be heavy drinkers (adjusted odds ratio [OR] = 2.16; 95% confidence interval [CI] 1.14, 4.09) and dependent on alcohol (adjusted OR = 2.02; 95% CI 1.08, 3.79) than operators who reported no domains of discrimination. The number of domains in which operators reported having experienced discrimination was not related to sex, age, household income, job seniority, or marital status, but varied significantly by educational level and race/ethnicity., Conclusions: Data from a sample of urban transit operators showed an association between the number of domains of discrimination and some alcohol-related outcomes, but not others.

In this article, as part of an evaluation of the future of medical education in California, we characterize the distribution of disease and injury in California; identify major factors that affect the epidemiology of disease and injury in California, and project the burden of disease and injury for California's population to the year 2007. Our goal is to elucidate the major causes of illness and disability at present and in the near future in order to focus state resources on the interventions likely to have the greatest impact. Data from various governmental agencies were utilized; the base year, 1993, is the most recent year with sufficient information available when this report was prepared. Several major risk factors have decreased, including smoking (30% decline from 1984 to 1993) and drinking and driving. However, hypertension prevalence has not changed, and overweight has increased dramatically. Poverty continues to burden about 15% of Californians, with poverty highest among children. During 1993, 220,271 Californians died, with 3 major causes accounting for 61% of these deaths: coronary heart disease (31%), cancer (23%), and stroke (7%). In terms of potential years of life lost (years lost before age 65), the most important causes of death in 1993 were unintentional injury (756 years lost/100,000 population), cancer (632 years), and the acquired immunodeficiency syndrome (AIDS; 491 years). Mortality rates were highest among blacks and lowest among Asians. Overall mortality in California has been declining for decades; in just 1 decade, from 1980 to 1991, mortality declined from 780 to 680 deaths per 100,000 population. Several major causes of death have declined, including coronary heart disease, stroke, unintentional injury, cirrhosis, and suicide, while others have increased, for example, chronic obstructive lung disease and diabetes mellitus. Death from AIDS increased dramatically in the past decade, but is leveling off, and death from cancer is beginning to decline. Rates for overall mortality and morbidity, and for most specific conditions, should continue to decline. A projected 28% population increase by 2007 will yield a corresponding increase in the absolute level of disease cases and death; a disproportionate increase in younger and older groups will yield increased conditions affecting young (unintentional injury, AIDS) and older (heart disease, cancer, stroke, diabetes mellitus) people. Californians should experience overall improved health in coming years, reaping benefits of reduced environmental and behavioral risk factors as well as improved medical treatment and rehabilitation. Coordinated strategies for health promotion, disease prevention, delivery of medical treatment, and rehabilitation are needed to maintain and improve present levels of health across the life span.

Urban transit operators' medical symptoms and conditions exceed other occupational groups, resulting partly from working conditions. Medical outcomes among operators have an impact on the transit system, including on performance, work attendance, and medical costs. This is exacerbated by external economic and political pressures in which expected service often exceeds the system's capacity in a congested, chaotic urban environment. A vicious cycle of poor working environment, reduced health and well-being among operators, and lowered efficiency and increased costs often results. Operator-health policies focusing solely on individuals are not sufficient to address these problems. A broader approach is needed, acknowledging the relationship between health of the system and health of employees, including redesigning the interface between transit systems and the urban environment and organizational change within companies. This comprehensive approach recognizes the dynamic reciprocity among the transit operators, the transit system, and the larger community.

The authors used observational job analysis as a conceptually based technique to measure stress factors unbiased by worker appraisal with 81 transit driving tasks on 27 transit lines. Stressor dimensions included work barriers that interfere with task performance due to poor technical-organizational design, time pressure, time binding (autonomy over time management), and monotonous conditions. Line-specific average stressor values were assigned to 308 transit operators who mainly worked the particular line. Logistic regression analyses showed associations for high work barriers and sickness absences (odds ratio [OR] = 3.8, p = .05). There were elevated risks for work accidents for high time pressure operators (OR = 4.0, p = .04) and for the medium time-binding group (OR = 3.3, p = .04) and significant (alpha = .20) unadjusted interaction terms for barriers and time pressure in predicting accidents and absences, and barriers and time binding in predicting absences. Findings suggest guaranteed rest breaks and flexible timing for accident prevention and removal of work barriers for reducing absenteeism.

In this study, data from transit vehicle operators of the San Francisco Municipal Railway (Muni), and a control group of individuals newly hired but not yet working as operators, were used to investigate prevalence of hypertension as a function of exposure to bus driving (years of driving), controlling for alcohol consumption and body mass index. Data were collected from transit vehicle operators in the course of their regular biennial examination during the period November 1983 to October 1985. Groups working as operators fewer than 10 years (n = 1137), from 10 to 20 years (n = 493), and more than 20 years (n = 196) were compared to each other and to a group of individuals with no prior exposure, but who were given a medical examination just before beginning their jobs as transit vehicle operators (n = 226). For hypertension (defined as systolic blood pressure > or = 140, or diastolic blood pressure > or = 90, or taking hypertension medication), the prevalence, adjusted for age, race, and gender, increased in a stepwise fashion from 28.8 percent in the group with no exposure to 38.9 percent in the group of drivers with more than 20 years on the job. A similar pattern was found for moderate to severe hypertension (systolic blood pressure > or = 160, or diastolic blood pressure > or = 95, or hypertension medication). These patterns were diminished, but not eliminated, when body mass index and alcohol consumption were considered. Higher rates of separation from employment for hypertensive operators suggested that the effect of years of employment may be underestimated by this cross-sectional comparison. Prolonged exposure to operating a transit vehicle may be associated with increased hypertension; increased alcohol consumption and body mass index with increased years of driving may account for at least some of the increased hypertension.

Eighty-one observational work analyses were conducted to measure stressors independently of worker appraisal in the San Francisco transit system. On the basis of action regulation theory, stress factors were defined as hindrances for task performance due to poor work organization or technological design. Stressors included (a) work barriers, defined as obstacles that cause extra work or unsafe behavior; (b) time pressure; (c) monotonous conditions; and (d) time binding, defined as control over timing. Reliability, measured as interrater agreement, ranged between 80 and 97%, with kappas of .46-.70. Validity analyses were done with 71 transit operators who participated in the observations and 177 operators who were assigned mean line-specific observational stressor measures. High odds ratios (ORs) were found for barriers and psychosomatic complaints (OR = 3.8, p = .00), time pressure and relaxation time needed after work (OR = 3.1, p = .05), and barriers and smoking to cope (OR = 3.8, p = .02). Using observational data in conjunction with self-report data can reduce confounding and improve interpretability of stress and health studies.

Objectives: This cross-sectional study examined associations between psychosocial job factors and the prevalence of nondisabling back and neck pain in professional drivers after physical work load was taken into account., Methods: A total of 1449 transit vehicle operators completed a medical examination and a questionnaire yielding information on demographic and anthropometric variables, health status, and physical and psychosocial job factors. Company records were used to supplement information on employment history. Physical work load was measured in life-time years and current weekly hours of professional driving. The relation of psychosocial factors with back or neck pain was analyzed by logistic regression models adjusted for past and current physical work load, vehicle type, age, gender, body height, and weight., Results: The main result of this study was that both physical work load and psychosocial factors were simultaneously and independently associated with back or neck pain. Psychosocial factors associated with back or neck pain included extended uninterrupted driving driving periods, frequency of job problems, high psychosocial demands, high job dissatisfaction, and low supervisory support. An analysis of specific job problems is provided which may be useful in setting priorities for research and intervention efforts in this high risk occupation., Conclusion: The results provide support for the role of psychosocial job characteristics in the etiology of back or neck pain in occupational settings.

The cohort consisted of 11,178 Mead Corporation employees (9,358 males and 1,820 females) who had worked for at least one year between January 1, 1975 and December 31, 1992 at seven pulp and/or paper mills in the United States. The vital status of the cohort was determined through a variety of sources over an observation period of 17 years (1976-1992). Mortality data were analyzed in terms of cause-specific standardized mortality ratios (SMRs), with expected deaths based on U.S. national mortality rates. Job categories with similar exposures were created based on an historical exposure assessment. Mortality analyses were performed separately for total female and male employees. Among female employees, overall mortality was less than expected, and no significant cause-specific mortality excesses were observed. The small number of deaths among female employees did not permit further detailed analyses. Among male employees, statistically significant deficits from overall mortality (SMR = 69.0) and from all cancers (SMR = 71.3) were reported. In addition, low mortality risks for many specific causes were also observed, including many specific cancer sites, various types of cardiovascular diseases, and different forms of nonmalignant respiratory diseases. In particular, there was no mortality excess from lung cancer (SMR = 77.5), digestive cancer (SMR = 69.4), stomach cancer (SMR = 46.7), laryngeal cancer (no observed death), rectal cancer (SMR = 82.8). Hodgkin's lymphoma (no observed death), non-Hodgkin's lymphoma (SMR = 103.6), leukemia (SMR = 72.2), diabetes mellitus (SMR = 110.4), ischemic heart disease (SMR = 80.0), and nonmalignant respiratory diseases (SMR = 36.7). Furthermore, detailed analyses by length of employment, interval since hire (latency), and job category demonstrated no occupationally related mortality increases from any of the diseases examined. Specifically, based on internal comparisons, no upward trends in cause-specific mortality risk were observed by duration of employment. In conclusion, the results of this epidemiologic investigation demonstrated a favorable mortality experience for employees at the seven pulp and/or paper mills.