Steering simulation performance in patients with obstructive sleep apnoea and matched control subjects. (33/1390)

Patients with obstructive pulmonary disease (OSA) have an increased rate of driving accidents, perhaps due to poor vigilance or impaired cognitive skills that influence their driving ability. The authors have assessed whether patients with OSA perform differently to control subjects on a steering simulator which allows the separate assessment of the two visual tasks required for steering a car, immediate positioning on road with reference to the road edges, and assessment of the curve of the oncoming road which allows faster driving. Twelve patients with OSA and 12 control subjects, matched for age, sex and driving experience, performed three 30-min drives with either all the oncoming road visible, only the near part of the road visible, or only the distant part of the road visible. Steering was assessed by measuring the SD around the theoretical perfect path (steering error) and the number of times the driver went "off road". Subjects identified the appearance of target numbers at the four corners of the screen as quickly as possible, thus making the test a divided attention task. Patients with OSA performed significantly less well on the three different road fields as measured by steering error (p<0.001), time to detect the target number (p<0.03), and off road events (p<0.03). The patients appeared to be particularly impaired on the two drives when only part of the road ahead was available to guide steering. This steering simulator, with its more realistic view of the road ahead, identifies impaired performance in patients with obstructive sleep apnoea. In addition it suggests that patients with obstructive sleep apnoea may be more disadvantaged compared to normal subjects when the view of the road ahead is limited (such as in fog).  (+info)

A single-photon emission computed tomography imaging study of driving impairment in patients with Alzheimer's disease. (34/1390)

Single-photon emission computed tomography (SPECT) was used in this study to examine the neurophysiologic basis of driving impairment in 79 subjects with dementia. Driving impairment, as measured by caregiver ratings, was significantly related to regional reduction of right hemisphere cortical perfusion on SPECT, particularly in the temporo-occipital area. With increased severity of driving impairment, frontal cortical perfusion was also reduced. Clock drawing was more significantly related to driving impairment than the Mini-Mental State Examination (MMSE). Driving impairment in Alzheimer's disease is related to changes in cortical function which vary according to the severity of the disease. Cognitive tests of visuoperceptual and executive functions may be more useful screening tools for identifying those at greatest risk for driving problems than examinations like the MMSE that are weighted toward left-hemisphere-based verbal tasks.  (+info)

Short-term exposure to air pollution in a road tunnel enhances the asthmatic response to allergen. (35/1390)

The aim of this study was to assess whether air pollution in road tunnels would promote asthmatic reactions in persons with mild allergic asthma. Twenty volunteers with mild allergic asthma were exposed, inside a car, for 30 min in a Stockholm city road tunnel. As a control, the subjects were exposed to much lower pollution levels in a suburban area. Four hours after the exposure, the subjects inhaled a low dose of allergen. Asthmatic reaction during the early phase was measured as the increase in specific airway resistance 15 min after allergen inhalation and during the late phase as the decrease in lung function forced expiratory volume in one second 3-10 h after allergen inhalation. Asthma symptoms and drug use were monitored up to 18 h after allergen inhalation. The median nitrogen dioxide level during exposure was 313 microg x m-3 (range 203-462). The median levels of particles with 50% cut-off aerodynamic diameters of 10 (PM10) and 2.5 microm (PM2.5) were 170 (range 103-613) and 95 (range 61-218) micro x m-3, respectively. Subjective symptoms during tunnel exposure were not pronounced. However, subjects exposed to tunnel N02 levels of > or = 300 microg x m-3 had a significantly greater early reaction, following allergen exposure, as well as lower lung function and more asthma symptoms during the late phase, compared to control. Also, subjects with PM2.5 exposure > or = 100 microg x m-3 had a slightly increased early reaction compared to control. In conclusion, exposure to air pollution in road tunnels may significantly enhance asthmatic reactions to subsequently inhaled allergens.  (+info)

Exposure of Paris taxi drivers to automobile air pollutants within their vehicles. (36/1390)

OBJECTIVES: To study the exposure of Parisian taxi drivers to automobile air pollutants during their professional activity. METHODS: A cross sectional study was carried out from 27 January to 27 March 1997, with measurements performed in the vehicles of 29 randomly selected drivers. Carbon monoxide (CO) content was measured over an 8 hour period by a CO portable monitor. The fine suspended particles were measured according to the black smoke index (BS), with a flow controlled portable pump provided with a cellulose filter. The nitrogen oxides, NO and NO(2) were measured with a passive sampler. RESULTS: These drivers are exposed during their professional activity to relatively high concentrations of pollutants (mean, median (SD) 3.8, 2 (1.7) ppm for CO, 168, 164 (53) micrograms/m(3) for BS, 625, 598 (224) micrograms/m(3) for NO, and 139, 131 (43) micrograms/m(3) for NO(2).) For CO the concentrations were clearly lower than the threshold values recommended by the World Health Organisation. The situation is less satisfactory for the other pollutants, especially for the BS index. All concentrations of pollutants recorded were noticeably higher than concentrations in air recorded by the ambient Parisian air monitoring network and were close to, or slightly exceeded, the concentrations measured at the fixed stations close to automobile traffic. Pollutant concentrations were also influenced greatly by weather conditions. CONCLUSION: This first French study conducted in taxi drivers shows that they are highly exposed to automobile pollutants. The results would justify a medical follow up of this occupational group.  (+info)

Risks older drivers face themselves and threats they pose to other road users. (37/1390)

BACKGROUND: Although there is an ever increasing literature on older drivers, there is no comprehensive up-to-date presentation of how older drivers are impacted by traffic safety, and how they impact the road safety of others. METHODS: This paper uses 1994-1996 US data to determine how many rates related to traffic safety depend on the age and sex of road users (fatalities, fatalities per licensed driver, etc.) Threats drivers pose to other road users are estimated by driver involvement in pedestrian fatality crashes. RESULTS: It is found that renewing the licence of a 70-year-old male driver for another year poses, on average, 40% less threat to other road users than renewing the license of a 40-year-old male driver. The fatality risks drivers themselves face generally increase as they age, with the increased risk of death in the same severity crash being a major contributor. If this factor is removed, crash risks for 70-year-old male drivers are not materially higher than for 40-year-old male drivers; for female drivers they are. CONCLUSIONS: Most driver rates increase substantially by age 80, in many cases to values higher than those for 20-year-olds. Given that a death occurs, the probability that it is a traffic fatality declines steeply with age, from well over 20% for late teens through mid twenties, to under one per cent at age 65, and under half a per cent at age 80.  (+info)

Earning a driver's license. (38/1390)

Teenage drivers in the United States have greatly elevated crash rates, primarily a result of qualities associated with immaturity and lack of driving experience. State licensing systems vary substantially, but most have allowed quick and easy access to driving with full privileges at a young age, contributing to the crash problem. Formal driver education has not been an effective crash prevention measure. Following the introduction of graduated licensing in New Zealand, Australia, and Canada, this system has been considered in many states and has been implemented in some. Graduated systems phase in full privilege driving, requiring initial experience to be gained under conditions of lower risk. The author describes the first five multistage graduated systems enacted in the United States in 1996 and 1997. Factors that will influence the acceptability and effectiveness of these new licensing systems are discussed.  (+info)

Increase in scrotal temperature in car drivers. (39/1390)

Several recent studies have reported a gradual decline in sperm production in men. Endocrine disrupters as well as lifestyle have been suggested as risk factors. One lifestyle factor that may affect human fertility is driving a vehicle for a prolonged period. Several authors have suggested that driving position may increase the scrotal temperature. In order to validate this hypothesis we conducted continuous monitoring of scrotal temperature in real conditions, i.e. in men driving a car for a prolonged period. Nine volunteer men were asked to walk outside for 40 min and then to drive a car for 160 min. Scrotal temperatures were measured from thermocouples and values recorded every 2 min on a portable data recorder. Scrotal temperature increased significantly (P < 0.0001) in driving posture after 2 h of driving, reaching a value 1.7-2.2 degrees C higher than that recorded while walking. This link between driving position and increased scrotal temperature indicates a potential exposure of male reproductive function to lifestyle factors.  (+info)

An epidemiologic study of occupational low back pain in truck drivers. (40/1390)

The factors in volved in occupational low back pain occurring in professional drivers were investigated epidemiologically with questionnaires (92 items) including low back symptoms, personal factors and occupational factors. The responses of one hundred fifty-three of one hundred eighty-one truck drivers who work in a large chemical industry corporation were analyzed after they had completely filled in questionnaires. As analysis of the results shows, the prevalence of LBP in one month of the survey was 50.3%. Correlating among data of personal factors and LBP, the prevalence of LBP was significantly higher in the drivers (Odd's ratio of 2.7) who answered "yes" to the item "shortage of spending time with family than in the drivers who didnt answer "yes. The occupational factors, working load and working environment showed no correlation with the prevalence of LBP. In contrast, 3 items of the working format related significantly to the prevalence of LBP: "irregular duty time (Odd's ratio of 3.0), "short resting time (2.4), and "long driving time in a day (2.0). Eighty-one of the 153 drivers (52.9%) pointed out the relationship between LBP and work, especially work which muolves vibration or road shock. Our results and the results from previous published studies suggested that vibration is an obvious risk factor for LBP. From the viewpoint of prophylaxis, an improvement in working conditions reduces the incidence of drivers' LBP to some extent.  (+info)