Roles of age, length of service and job in work-related injury: a prospective study of 63,620 person-years in female workers.

BACKGROUND: The roles of age, length of service and job in various work-related injury types are unknown and deserve investigations among female workers. This study assessed their roles in the occurrence of injury. METHODS: Three-year prospective study of all 22,952 permanently employed women at the French national railway company: 63,620 person-years, 756 injuries with working days lost, coded using the company's injury classification derived from that of the French health insurance scheme. We investigated the incidence of four types of injury: fall on same level, fall to lower level, materials/equipment/objects handling, and other injuries. Data were analyzed using negative binomial regression. RESULTS: Workers aged <25 were subject to a higher risk for all types of injuries. Older workers (45-55 years) were subject to a higher injury risk for fall on same level and fall to lower level. For fall on same level as for fall to lower level the relative risk decreased steadily with increasing length of service with the company, from 1.60 for 1 year to 0.50-0.60 for ≥30 years. For injuries due to materials/equipment/objects handling the relative risk decreased from 1.05 for one year to 0.49 for 5-9 years, and then increased to about 1.50 for 20-29 years and ≥30 years. CONCLUSIONS: Younger and shorter lengths of service were at risk for various types of injuries. Higher length of service was at risk for injury due to materials/equipment/objects handling. Preventive measures should consider the respective risks associated with age, years of employment and job.

Impaired neuromotor functions in hospital laboratory workers exposed to low levels of organic solvents.

Solvents are ubiquitous in industrial societies in a wide range of processes, and long-term exposure to these organic compounds may impair neuromotor functions such as equilibrium function. However, there is limited knowledge of effects on posture and gaze control after organic solvent exposures below workplace threshold limit values. The aim of this study was to evaluate the consequences of low-level co-exposure to organic solvents on balance and gaze control in hospital laboratory workers. Twelve hospital laboratory female subjects mainly exposed to toluene and ethanol, with median exposure duration of 24 years, and 12 non-exposed female controls were submitted to posturography and oculomotricity testings including sensory organization and motor control tests and saccade and smooth pursuit tests. Although current measured exposure values to toluene and ethanol were much below workplace threshold limit values (current median exposure levels of 32.5 mg/cubic meter and 39.9 mg/cubic meter, respectively), exposed workers displayed a weaker balance and a less precise gaze control. They presented, on the one hand, a reduced ability to resolve sensorial conflict situations compared to controls, particularly when situations were managed by the vestibular information, and, on the other hand, longer saccadic reaction time. Organic solvents might have an impact on vestibular pathways involved in postural control and exert a depressant central pathway effect implicated in the management of oculomotor response. Evaluating balance control in sensory conflicting situations and saccadic reaction time is proposed as a way to reveal subclinical neurotoxicological effects due to low-level exposure to organic solvents.

Association of physical job demands, smoking and alcohol abuse with subsequent premature mortality: a 9-year follow-up population-based study.

This study assessed the relationships of physical job demands (PJD), smoking, and alcohol abuse, with premature mortality before age 70 (PM-70) among the working or inactive population. The sample included 4,268 subjects aged 15 or more randomly selected in north-eastern France. They completed a mailed questionnaire (birth date, sex, weight, height, job, PJD, smoking habit, alcohol abuse (Deta questionnaire)) in 1996 and were followed for mortality until 2004 (9 yr). PJD score was defined by the cumulative number of the following high job demands at work: hammer, vibrating platform, pneumatic tools, other vibrating hand tools, screwdriver, handling objects, awkward posture, tasks at heights, machine tools, pace, working on a production line, standing about and walking. The data were analyzed using the Poisson regression model. Those with PM-70 were 126 (3.81 per 1,000 person-years). The leading causes of death were cancers (46.4% in men, 57.1% in women), cardiovascular diseases (20.2% and 11.9%), suicide (9.5% and 7.1%), respiratory diseases (6.0% and 4.8%), and digestive diseases (2.4% and 4.8%). PJD3, smoker, and alcohol abuse had adjusted risk ratios of 1.71 (95% CI 1.02-2.88), 1.76 (1.08-2.88), and 2.07 (1.31-3.26) respectively for all-cause mortality. Manual workers had a risk ratio of 1.84 (1.00-3.37) compared to the higher socio-economic classes. The men had a two-fold higher mortality rate than the women; this difference became non-significant when controlling for job, PJD, smoker and alcohol abuse. For cancer mortality the factors PJD3, smoker, and alcohol abuse had adjusted risk ratios of 2.00 (1.00-3.99), 2.34 (1.19-4.63), and 2.22 (1.17-4.20), respectively. Health promotion efforts should be directed at structural measures of task redesign and they should also concern lifestyle.

Relationships of physical job tasks and living conditions with occupational injuries in coal miners.

This study assessed the relationships of job tasks and living conditions with occupational injuries among coal miners. The sample included randomly selected 516 underground workers. They completed a standardized self-administred questionnaire. The data were analyzed via logistic regression method. The rate of injuries in the past two years was 29.8%. The job tasks with significant crude relative risks were: power hammer, vibrating hand tools, pneumatic tools, bent trunk, awkward work posture, heat, standing about and walking, job tasks for trunk and upper/lower limbs, pain caused by work, and muscular tiredness. Logistic model shows a strong relationship between the number of job tasks (JT) and injuries (adjusted ORs vs. JT 0-1: 2.21, 95%CI 1.27-3.86 for JT 2-6 and 3.82, 2.14-6.82 for JT>or=7), and significant ORs>or=1.71 for face work, not-good-health-status, and psychotropic drug use. Musculoskeletal disorders and certain personality traits were also significant in univariate analysis. Therefore job tasks and living conditions strongly increase the injuries, and occupational physicians could help workers to find remedial measures.

Contributions of occupational hazards and human factors in occupational injuries and their associations with job, age and type of injuries in railway workers.

OBJECTIVES: To assess the contributions of environmental hazards, technical dysfunctions, lack of work organization, know-how and job knowledge, and other human factors in occupational injuries and their relationships with job, age and type of accidents in railway workers. METHODS: The sample included 1,604 male workers, having had at least one occupational injury with sick leave during a 2-year period in voluntary French railway services. A standardized questionnaire was filled in by the person-in-charge of prevention, with the injured worker. Data analysis was performed via the chi(2) independence test and adjusted odds ratios (OR) with Mantel-Haenszel test. RESULTS: The environmental hazards were implicated in 24.7%, technical dysfunctions in 16.0%, lack of work organization in 13.7%, lack of know-how in 17.6%, lack of job knowledge in 5.2%, and the other human factors in 31.9% of occupational injuries. The injuries caused by lack of know-how or job knowledge were more represented in workers aged less than 30 (ORs adjusted for job 1.45, 95% CI 1.02-2.06 and 2.06, 1.22-3.49, respectively), those by environmental hazards in energy and electrical traction maintenance operators and train drivers (ORs adjusted for age 2.04, 1.16-3.58 and 1.80, 1.01-3.20, respectively), and those by lack of work organization in mechanical maintenance operators and in energy and electrical traction maintenance operators (ORs adjusted for age 2.24, 1.13-4.45 and 1.83, 1.30-2.57, respectively). The causes considered were strongly related with the type of injuries. CONCLUSIONS: This study found that environmental hazards, technical dysfunctions, lack of work organization, lack of knowledge and other human factors had important contributions in injuries, and they were related to job, age and type of injuries. These findings are useful for prevention. Training is necessary for young workers. The occupational physician could help the workers to be more aware of the risks.

Prevalence of sensory and cognitive disabilities and falls, and their relationships: a community-based study.

This study assessed the prevalence of sensory and cognitive disabilities and falls for various age groups, sexes, and socio-occupational categories, and their associations in the Lorraine population. The sample included 6,159 subjects, aged 15 years or more, randomly selected from the Lorraine population. They filled in a mailed questionnaire including socio-demographic characteristics, job, falls with physical injuries at the time of the survey, and sensory and cognitive disabilities. Data analysis was made via the adjusted odds ratios. The prevalences of sensory and cognitive disabilities were 3.0 and 4.7%, respectively, that of falls with physical injuries 2.4%: 1.2% for falls on the same level and 1.2% for falls to a lower level. Subjects aged over 70 were markedly affected, but the other age groups had relatively high prevalences as well; the workmen had the highest prevalence, followed by the foremen, farmers, craftsmen and tradesmen, and employees. A twofold risk independently of age, sex and job was found for the subjects with sensory or cognitive disabilities for all falls combined. These findings show the high prevalences of sensory and cognitive disabilities and falls with physical injuries, and their strong associations in the general population. Preventive measures are needed to detect and follow up the persons with these disabilities, limit their risk of falls and reduce occupational hazards.

Long-term exposure to solvents impairs vigilance and postural control in serigraphy workers.

OBJECTIVES: To investigate the effects of solvent exposure (mainly aromatic hydrocarbons) on central regulation of vigilance and postural control, particularly in occasional difficult situations that provide sensorial conflicts. METHODS: Twenty-two workers occupationally exposed to solvents for an average of approximately 6 years and 21 controls were compared by the use of a questionnaire on their state of vigilance and quality of sleep and on performance measurements of postural control under six different sensorimotor conditions. Their current median exposure levels to aromatic hydrocarbons was 80.1 mg/m(3). RESULTS: Exposed workers reported reduced alertness but not disturbance of sleep quality compared with controls. Moreover, they had the worst postural performance in all sensory conditions and demonstrated a reduced ability to resolve sensory conflict situations. The precision of stance was clearly affected by solvent exposure in contrast with energy consumption required to regulate proper balance control. CONCLUSIONS: The depressive effect of aromatic hydrocarbon exposure on cortical and subcortical structures controlling vigilance and postural stability could lead to increased risk of occupational accident, especially due to falls. The detection of central neurotoxic effects by posturographic and vigilance tests could be useful in preventive strategies.

Chronic exposure to anesthetic gases affects balance control in operating room personnel.

Exposure to anesthetic gases is known to alter certain structures and functions of the central nervous system. As the effects of long-term exposure on balance control mechanisms have been the subject of few investigations, these were evaluated in 53 operating room personnel exposed to anesthetic gases and in 53 non-exposed individuals. Balance control was assessed by static and dynamic posturography. Exposed workers had the worst static and dynamic postural performances, particularly in the eyes closed condition, suggesting increased dependency on vision and decreased use of proprioception. This poorer ability to modify the weight and to switch the different cues controlling balance suggests central information processing disorders. By impairing information and its central integration, exposure to anesthetics gases leads to inappropriate organization of sensorimotor stabilization strategies.

Correlates of occupational injuries for various jobs in railway workers: a case-control study.

Few studies have simultaneously addressed the role of occupational factors, individual characteristics and living conditions in occupational injuries, and to the best of our knowledge none on railway workers. This survey assessed the roles of these factors in various types of injuries and for various jobs in French railway workers. This case-control study was conducted on 1,305 male workers with an occupational injury during a one-year period and 1,305 male controls. A standardized questionnaire was administrated by an occupational physician. Data were analyzed by the logistic regression method. The significant factors found for all the injuries combined were: young age (<30 yr) (adjusted odds ratio 1.47, 95% CI 1.01-2.14), 5 yr or less in present job (1.43, 1.15-1.78), sleep disorders (1.30, 1.08-1.57), current smoker (1.27, 1.08-1.50), and no do-it-yourself or gardening activity (1.23, 1.02-1.48). Young age, sleep disorders, and smoking were common for several types of injuries. The role of these factors differed between various job categories. Among injured workers sick leaves of eight days or over were more frequent in current smokers and overweight subjects. In conclusion, young age, lack of experience, job dissatisfaction, sleep disorders, smoking, and lack of physical activity increase the risk of occupational injuries. The risks induced were related with jobs. Preventive measures concerning work conditions and these factors could be conducted in railway workers generally, and especially in workers most at risk. The occupational physician could make workers more sensitive to these risks and help them to improve their living conditions during medical examinations.

Sensorial organisation favouring higher visual contribution is a risk factor of falls in an occupational setting.

The contribution of intrinsic balance control factors to fall mechanisms has received little investigation in studies on occupational accidents. The aim of this study was to assess whether postural regulation in falling workers might have specificities in terms of sensorimotor strategies and neuromuscular responses to balance perturbations. Nine multi-fall-victims (MF), 43 single-fall-victims (SF) and 52 controls (C) were compared on performance measurements of static and dynamic postural control. MF and SF had the worst postural performance both in the static and slow dynamic tests, particularly in eyes closed conditions, suggesting a high dependency on visual cues and a lower use of proprioception. Moreover, the sensorial analysis showed that MF and SF relied less on vestibular input in the development of balance strategy and had more difficulties in maintaining a correct upright stance when proprioceptive input was altered. Finally, MF showed longer latency responses to unexpected external disturbance. Overall, postural control quality increased in the order MF, SF and C. MF and SF adopted particular sensorimotor organisation, placing them at an increased risk of falling in specific sensory environments. Strategies incorporating visual information involve using the cognitive processes causing delayed and less accurate fall avoidance responses, in contrast to adaptative strategies based on proprioceptive and vestibular information.

Relationships of job, age, and life conditions with the causes and severity of occupational injuries in construction workers.

OBJECTIVES: To assess the relationships of job, age, and life conditions with the causes and severity of occupational injuries in male construction labourers. METHODS: The sample included 880 male construction workers having had at least one occupational injury with subsequent sick leave. The survey used a standardised questionnaire, filled in by the occupational physician in the presence of the subject: socio-demographic data, job, safety training, smoking habit, alcohol consumption, sporting activities, physical disabilities, hearing, vision, and sleep disorders. Statistical analysis was via the logistic regression method. RESULTS: Logistic models showed that falls and injuries from the handling of objects or hand tools was similar for all jobs, while masons, plumbers and electricians had a higher risk of injury from moving objects, and carpenters, roofers and civil-engineering workers were more exposed to injury from construction machinery and devices. Age <30 was related to injury from hand tools [adjusted OR (95%CI) 2.20 (1.28-3.79)]; sleep disorders and hearing disorders to those from moving objects [ORs 2.29 (1.27-4.12) and 1.85 (1.01-3.41) respectively]; no sporting activity to those from the handling of objects [OR 1.54 (1.09-2.17)]; and being overweight to falls on the same level [OR 2.04 (1.30-3.21)] and falls to a lower level [OR 1.55 (1.13-2.13)]. Injuries from the handling of objects were less frequent in overweight workers [OR 0.62 (0.46-0.84)]. Injuries with hospitalisation or sick leave > or =60 days were associated with age > or =30 and hearing disorders. CONCLUSIONS: The causes of injuries were related to jobs. Prevention through working conditions could be made against the revealed risks. The risks for each worker depended on age, body mass index, hearing disorders, sleep disorders, and sporting activities. The occupational physician could inform the workers of these risks and encourage them to practise sporting activities and reduce their hearing disorders and sleep disorders.

Relationships between certain individual characteristics and occupational injuries for various jobs in the construction industry: a case-control study.

BACKGROUND: There is little published about the role of individual characteristics in occupational injuries. Construction workers have a high rate of injury; we assessed 11 personal characteristics in this professional sector. METHODS: A case-control study was conducted on 880 male workers who had had at least one occupational injury during a 2-year period and 880 controls. A questionnaire was administered by an occupational physician. Statistical analysis was made via logistic regression method. RESULTS: Young age (<30 years), sleep disorders and current smoker influenced all the injuries combined. Sleep disorders and young age were common risk factors for several jobs. Physical disabilities and no sporting activity had a role in masons, and 5 years or less in present job in plumbers and electricians only. Sleep disorders influenced both the injuries with and without hospitalization; young age, current smoker, and physical disability influenced those without hospitalization only. CONCLUSIONS: Young age, sleep disorders, smoking, disabilities, sporting activity, and experience influenced the occupational injuries. The risk for each worker depended on his job. Occupational physicians could inform the workers of these risks and encourage them to take remedial action.

Relationships of job and some individual characteristics to occupational injuries in employed people: a community-based study.

This study assessed the associations of job and some individual factors with occupational injuries among employed people from a general population in north-eastern France; 2,562 workers were randomly selected from the working population. A mailed auto-questionnaire was filled in by each subject. Statistical analysis was performed with loglinear models. The annual incidence rate of at least one occupational injury was 4.45%. Significant contributing factors for occupational injuries were job category (60.8%), sex (16.2%), regular psychotropic drug use (8.5%), age groups (7.5%), and presence of a disease (7.0%). The men had higher risk than the women (adjusted odds-ratio 1.99, 95% CI 1.43-2.78). Compared to executives, intellectual professionals and teachers, labourers had the highest risk (6.40, 3.55-11.52). They were followed by farmers, craftsmen and tradesmen (6.18, 2.86-13.08), technicians (3.14, 1.41-6.70), employees (2.94, 1.59-5.48) and other subjects (3.87, 1.90-7.88). The young (< or = 29 yr) showed an increased risk. Similar odds-ratios were observed for regular psychotropic drug use (1.54, 1.16-2.05) and the presence of a disease (1.50, 1.11-2.02). Univariate analysis showed that smoking habit, overweight and excess alcohol use were also associated with injuries. The loglinear model results showed that there were associations between some of these independent factors. It was concluded that job, sex, young age, smoking habit, excess alcohol use, overweight, psychotropic drug use, and disease influenced the occupational injuries. Preventive measures concerning work conditions, risk assessment and job knowledge should be conducted in overall active population, especially in men, young workers, smokers, alcohol users, overweight workers and in individuals with a disease or psychosomatic disorders.