Relationship between Walking and Driving, and Cognitive Functioning Common to Both Modes of Mobility, in Healthy Older Adults

INTRODUCTION

Driving and walking, the two main modes of mobility, require numerous common skills in the motor, sensory, and cognitive domains that deteriorate with age. The objective of this study was to investigate the relationship between walking and driving in healthy older drivers and to determine whether certain cognitive processes are involved in both modes of mobility.

METHOD

Seventy-six older drivers from the Safe Move cohort were assessed in the following three domains: (1) cognition, using parts A and B of the Trail Making Test (TMT), the digit symbol substitution test (DSST), the Stroop test, and the Digit span; (2) gait, using a dual-task (DT) paradigm with a counting task; and (3) driving, assessed via a 40-50 min on-road test. Analyses were also performed on 2 subgroups: young-old (70-74 years old; n = 43) and old-old (≥75 years; n = 33).

RESULTS

Four significant correlations were found across the whole sample between gait performance under DT conditions and driving scores. One correlation was also found in old-old adults. None were found in young-old adults. Furthermore, several cognitive measures were significantly correlated to both modes of mobility: TMT-A and B completion time in the whole sample, and DSST performance in the whole sample and old-old adults.

DISCUSSION/CONCLUSION

Walking in complex conditions and on-road driving performance are closely related in healthy older drivers. Visuospatial attention, processing speed, and executive function are crucial and common cognitive processes to both modes of mobility in this population. Impairment in these cognitive functions should thus alert health professionals as it can quickly lead to mobility disorders, loss of autonomy and social isolation. Developing specific preventive programs and mobility support systems for healthy older adults is also crucial.

Relationships Between Cognitive and Driving Self-awareness in Older Drivers

OBJECTIVES

Many older drivers incorrectly estimate their driving ability. The present study aimed to determine whether, and if so, to what extent unawareness of cognitive abilities affects self-awareness of driving ability.

METHOD

Two successive studies were conducted in older drivers. A cohort study investigated cognitive self-awareness and an experimental study examined driving self-awareness. In each one, self-awareness was assessed by cross-analyzing objective (respectively Trail-Making Tests A and B and the Digit Symbol Substitution Test and driving performance of on-road assessment) and subjective data (responses about everyday cognitive skills and driving ability). Older drivers were then classified as being over-, correct, or underestimators. The 3 cognitive and driving self-awareness profiles were then cross-analyzed.

RESULTS

In the cohort study, 1,190 drivers aged 70 years or older were included. The results showed that 42.7% of older drivers overestimated their cognitive ability, 42.2% estimated it correctly, and 15.1% underestimated it. The experimental study included 145 participants from the cohort. The results showed that 34% of participants overestimated, 45% correctly estimated, and 21% underestimated their driving ability. There was a significant relationship between cognitive and driving self-awareness profiles (p = .02). This overlap was more marked in overestimators.

DISCUSSION

Significant overlap between cognitive and driving self-awareness provides useful and new knowledge about driving in the aging population. Misestimation of cognitive ability could hamper self-awareness of driving ability, and consequently self-regulation of driving. It is now crucial to develop measures that promote self-awareness of ability.

Knockout of hyaluronidase Spam1 reduces age-related bone and cartilage changes in mouse knee

OBJECTIVE

To investigate the role of Spam1 hyaluronidase in age-related bone and cartilage changes in the mouse knee.

DESIGN

Spam1^-/- and WT mice were euthanised at different ages from 10 to 52 weeks. The right hindlimbs were dissected, scanned with peripheral Quantitative Computed Tomography (pQCT) and then decalcified for histological analysis (modified Mankin score). In other mice, cartilages of both tibiae were sampled at 10, 30 and 52 weeks of age for RNA extraction and qPCR analysis. We assessed the expression of hyaluronidases Hyal1 and Hyal2, hyaluronan synthase HAS2, extracellular matrix proteases Mmp13 and Adamts-5, and type 2 collagen.

RESULTS

Spam1^-/- mice did not exhibit specific morphological characters up to 52 weeks of age. From 20 weeks, the proximal tibia of Spam1^-/- mice had a significantly lower bone mineral density than WT mice. At 52 weeks, the modified Mankin score was significantly lower in Spam1^-/- than WT mice. Spam1^-/- chondrocytes expressed significantly less Hyal2 than WT ones at all ages and less Mmp13 at 52 weeks. Through all the experiment, the Hyal1 expression of Spam1^-/- chondrocytes remained similar as that of WT chondrocytes.

CONCLUSION

Spam1 knockout reduced significantly cartilage degradation in mouse knee whereas the chondrocyte expression of Hyal 1, Hyal 2 and Mmp13 was modified, suggesting a role of this hyaluronidase in cartilage metabolism.

Barriers and facilitators to social participation after driving cessation among older adults: A cohort study

BACKGROUND

Driving cessation is a challenging transition for older drivers. It is indeed often associated with reduced mobility, loss of autonomy and poor quality of life, as in individuals with acquired disabilities. We examined factors that inhibit or facilitate out-of-home occupations after driving cessation (shopping, visiting/helping friends/family, leisure, and associative activities) in older adults, with particular focus on the role of anticipation.

METHODS

This longitudinal study was conducted with the SAFE MOVE cohort (n=1014 drivers aged≥70 years). Socio-demographic, health, cognitive, mobility and out-of-home occupations data were collected at home at baseline and by a postal questionnaire at 2-year follow-up.

RESULTS

In total, 48 (5%) participants stopped driving between baseline and follow-up, at a mean age of 81.8 years; 71% of drivers who stopped reported that driving cessation affected their out-of-home occupations. Participation in social occupations started to decline before driving cessation. Retired drivers were older, had poorer health, poorer cognitive abilities, drove less at baseline but used more public transportation than active drivers. As compared with participants who did not consider driving cessation at baseline, those who did were more likely to expect a better quality of life in the event of driving cessation and to use public transportation at baseline and follow-up despite their older age and poorer health.

CONCLUSION

Some factors associated with reduced social participation and driving cessation are inevitable, such as health status. However, other factors may facilitate maintenance of social participation, including anticipation of driving cessation and mobility habits. Our findings highlight the need for appropriate interventions that are widely available to older drivers before driving cessation occurs and for public policy actions facilitating alternative transport systems.

Chronic medical conditions and their association with crash risk and changes in driving habits: a prospective study of the GAZEL cohort

OBJECTIVES

To assess crash risk and driving habits associated with chronic medical conditions among drivers entering old age.

DESIGN

Prospective cohort study.

SETTING

French cohort GAZEL.

PARTICIPANTS

12 460 drivers in the analysis of road traffic crash, among whom 11 670 completed the follow-up period (2007-2014). We assessed driving cessation among 11 633 participants over the same period, and mileage and driving avoidance among the 4973 participants who returned a road safety questionnaire in 2015.

MAIN OUTCOME MEASURES

Yearly occurrence of at least one road crash as a driver; time to driving cessation; mileage; driving avoidance: at night, with bad weather, in heavy traffic, with glare conditions, over long distances.

RESULTS

Several potentially risky conditions (angina, myocardial infarction, coronary disease; stroke; nephritic colic, urinary stones; glaucoma) were associated with lower mileage and/or driving avoidance and did not increase crash risk. Neither driving avoidance nor lower mileage was found for other conditions associated with an increased crash risk: hearing difficulties (adjusted OR 1.19, 95% CI 1.06 to 1.34); joint disorders (1.17, 95% CI 1.06 to 1.30). Depression, anxiety and stress was associated with an increased crash risk (1.23, 95% CI 1.01 to 1.49) despite increased driving avoidance. Parkinson's disease was associated with driving cessation (adjusted HR 32.61, 95% CI 14.21 to 65.17).

CONCLUSIONS

Depending on their condition, and probably on the associated risk perception, drivers entering old age report diverse driving habits. For example, hearing difficulties is a frequent condition, rarely considered a threat to road safety, and nonetheless associated with an increased crash risk.

Naturalistic Driving Study Investigating Self-Regulation Behavior in Early Alzheimer's Disease: A Pilot Study

BACKGROUND

Because cognitive processes decline in the earliest stages of Alzheimer's disease (AD), the driving abilities are often affected. The naturalistic driving approach is relevant to study the driving habits and behaviors in normal or critical situations in a familiar environment of participants.

OBJECTIVE

This pilot study analyzed in-car video recordings of naturalistic driving in patients with early-stage AD and in healthy controls, with a special focus on tactical self-regulation behavior.

METHODS

Twenty patients with early-stage AD (Diagnosis and Statistical Manual of Mental Disorders, Fourth Edition [DSM-IV] criteria), and 21 healthy older adults were included in the study. Data collection equipment was installed in their personal vehicles. Two expert psychologists assessed driving performance using a specially designed Naturalistic Driving Assessment Scale (NaDAS), paying particular attention to tactical self-regulation behavior, and they recorded all critical safety events.

RESULTS

Poorer driving performance was observed among AD drivers: their tactical self-regulation behavior was of lower quality. AD patients had also twice as many critical events as healthy drivers and three times more "unaware" critical events.

CONCLUSION

This pilot study used a naturalistic approach to accurately show that AD drivers have poorer tactical self-regulation behavior than healthy older drivers. Future deployment of assistance systems in vehicles should specifically target tactical self-regulation components.

Gender effect on driving cessation in pre-dementia and dementia phases: results of the 3C population-based study

OBJECTIVES

Aging entails deterioration in sensory, physical, and cognitive functions, raising doubt in the driving capacity of older drivers, especially when the deficits are severe, as in dementia. Many older drivers, especially women, adapt their driving habits in order to compensate for these deficits and eventually stop driving. The present prospective study assessed driving cessation in men and women throughout the dementia process, including a 2-year pre-dementia phase.

METHODS

The study was based on a three-city cohort of subjects who were aged 65 years and older in 2000 and followed for more than 10 years. Active dementia detection was conducted at each follow-up. The probability of driving cessation was assessed in men and women during the 2-year pre-dementia phase and until 5 years after diagnosis.

RESULTS

In the 2-year pre-dementia phase, both men and women ceased driving earlier than drivers with no central nervous system pathology (p < 0,001), and women ceased driving earlier than men. A total of 45% of men and 74% of women had already ceased driving at dementia diagnosis. In contrast, the probability of cessation within 3 years after diagnosis was similar between men and women.

CONCLUSION

The study showed that, in this French urban population, few demented drivers, especially women, were still driving after diagnosis. Those who continued to drive 3 years after the diagnosis all had Alzheimer-type dementia. There is certainly a need for physicians to help these drivers to adapt their driving activity to their deficits and to prepare them to stop driving. Copyright © 2016 John Wiley & Sons, Ltd.

The role of navigation instruction at intersections for older drivers and those with early Alzheimer's disease

AIMS

Our purpose was to explore the effect of navigation instruction on older drivers' driving performance at left turn intersections. Left turns at intersections are particularly complex because they require many perceptive and cognitive abilities under considerable time pressure.

METHODS

Fifty-four participants were recruited: 18 drivers with early-stage Alzheimer's disease (AD), 18 neurologically healthy older drivers and 18 younger individuals. Various cognitive processes were measured, and 9 left turn maneuvers with or without navigation instruction were evaluated during an in-traffic road test. The psychomotor, planning and decision-making components involved in left turn were also analyzed closely.

RESULTS

Only older drivers (both healthy drivers and those with AD) were negatively affected by navigation instruction during the maneuver. The planning and decision-making components were more likely to be affected by the navigation instruction.

CONCLUSION

This finding highlights the importance of carefully considering the use of navigation instructions when developing navigation systems. Adapting this instruction is necessary to simplify our understanding of the real-world driving environment and to avoid increasing the cognitive load of older drivers.

Automobile driving in older adults: factors affecting driving restriction in men and women

OBJECTIVES

To identify factors associated with driving restriction in elderly men and women.

DESIGN

Prospective cohort study of French drivers from 2003 to 2009.

SETTING

The Three-City Cohort of Bordeaux, a prospective study of 2,104 people aged 65 and older.

PARTICIPANTS

Five hundred twenty-three drivers with a mean age of 76 (273 male, 250 female).

MEASUREMENTS

Sociodemographic characteristics, driving habits, health variables, cognitive evaluation and dementia diagnosis. Predementia was defined as no dementia at one follow-up and dementia at the next follow-up.

RESULTS

Over the 6-year period, 54% of men and 63% of women stopped driving or reduced the distance they drove. Predementia, Parkinson's disease, older age, and a high number of kilometers previously driven were common restriction factors in both sexes. Prevalent dementia, depressive symptomatology, a decline in one or more instrumental activities of daily living, and poor visual working memory were specific factors in men. In women, low income, fear of falling, slow processing speed, and severe decline in global cognitive performance all affected driving restriction.

CONCLUSION

Older women restricted their driving activity more than older men, regardless of the number of kilometers previously driven, physical health, and cognitive status. Factors affecting driving restriction differed according to sex, and women were more likely to stop driving than men in the period preceding a dementia diagnosis.

The Wechsler Digit Symbol Substitution Test as the best indicator of the risk of impaired driving in Alzheimer disease and normal aging

AIMS

Our purpose was to identify cognitive tools associated with unsafe driving among elderly drivers of varying cognitive levels.

METHODS

Twenty drivers with early-stage dementia of the Alzheimer type and 56 nondemented drivers aged 65-85 were recruited. Various cognitive processes were measured and unsafe driving was evaluated during an in-traffic road test with 3 different indicators and a composite indicator.

RESULTS

The Wechsler Digit Symbol Substitution Test score was the best cognitive measure to detect unsafe drivers using the composite driving indicator.

CONCLUSION

The Digit Symbol Substitution Test may be used by physicians for the evaluation and follow-up of older patients, with or without Alzheimer-type dementia, as a screening tool of unsafe driving.

Failure to reduce drinking and driving in France: a 6-year prospective study in the GAZEL cohort

AIM

An unprecedented decline in alcohol consumption and road mortality has been observed recently in France, but it is still unclear whether or not these changes affected driving while alcohol-intoxicated (DWI). The objective of the study was to estimate prospectively trends of excessive speed on the roads, alcohol consumption and DWI between 2001 and 2007 in a large cohort of experienced drivers.

METHODS

Participants were current employees or recent retirees of the French national electricity and gas company, who volunteered to participate in a research cohort established in 1989 under strict conditions of anonymity. An annual cohort questionnaire is sent to participants that includes two questions about overall alcohol consumption. In 2001 and 2007, 10,684 participants reported their driving behaviours using the same self-administered questionnaire.

RESULTS

Between 2001 and 2007, the proportion of participants (n = 10,684) who reported having driven at speeds at least 20 km/hour above the limit decreased from 23.7% to 4.1% in built-up areas (P < 0.001), from 34.3% to 9.3% on rural roads (P < 0.001) and from 24.3% to 2.7% on highways (P < 0.001). Regular and non-regular excessive alcohol consumption decreased from 22.7% to 19.7% and from 18.0% to 14.9%, respectively, whereas DWI increased from 22.9% to 25.3% over the same period (P < 0.001).

CONCLUSIONS

A recent crackdown on road violations by the French government has failed to deter DWI. Given that DWI seems to be a sporadic and rarely punished behaviour, its prevention requires more coercive measures, such as using a breath alcohol ignition interlock device.

Road casualties and changes in risky driving behavior in France between 2001 and 2004 among participants in the GAZEL cohort

OBJECTIVES

We investigated behavioral changes in a large cohort of drivers to identify underlying causes of the decline in road casualties in France.

METHODS

In 2001 and 2004, 11,240 participants used self-administered questionnaires to report attitudes toward road safety and driving behaviors. Injury road traffic collisions were recorded from 2001 to 2005 through the cohort's annual questionnaire.

RESULTS

Between 2001 and 2004, speeding and cell phone use decreased concomitantly with a decrease in injury road traffic collision rates among participants. Reported driving while sleepy remained unchanged and driving while alcohol intoxicated was reported by a higher proportion in 2004 than in 2001. Decreases in speeding between 2001 and 2004 were strongly linked with positive attitudes toward road safety in 2001.

CONCLUSIONS

In this cohort, speeding and using a cell phone while driving decreased over the 2001 to 2004 period concomitantly with increases in traffic law enforcement and a dramatic decline in road mortality in France. However, the deterrent effect of traffic enforcement policies may have been reduced by negative attitudes toward traffic safety and having had a history of traffic penalty cancellations.

The recent dramatic decline in road mortality in France: how drivers' attitudes towards road traffic safety changed between 2001 and 2004 in the GAZEL cohort

A very significant decline in the number of road casualties has been observed recently in France, concomitantly with a dramatic increase in law enforcement. The aim of this study was (i) to assess changes in attitudes about road traffic accident (RTA) prevention initiatives in France from 2001 to 2004 and (ii) to identify factors associated with an increase in positive attitudes towards RTA prevention initiatives. In 2001 and 2004, 9216 participants reported their attitudes towards traffic safety using the same self-administered Driving Behaviour and Road Safety Questionnaire. Sociodemographic, psychological and behavioural data were also available. The mean change in scores analysis showed that support for relaxing existing regulations decreased significantly during this period, while support for heightened enforcement and stricter regulations showed some decrease but remained high overall, especially concerning blood alcohol content and speed controls. Multivariate analyses suggest that highly educated drivers changed their attitudes towards road safety regulations more than other categories. Our results suggest that increased traffic law enforcement measures led to increasing support for current restrictions. Even if support for additional traffic law enforcement began to wane slightly in 2004, a large part of our population remained in favour of strengthening law enforcement related to speeding and drunk driving.

Driving cessation and self-reported car crashes in older drivers: the impact of cognitive impairment and dementia in a population-based study

The complexity of driving activity has incited numerous developed countries to initiate evaluative procedures in elderly people, varying according to first evaluation age, frequency, and screening tools. The objective of this paper is to improve the knowledge of the driving cessation process regarding factors associated with crash involvement. Driving cessation and self-reported crashes during the past 5 years were analyzed with multivariate models, in a cross-sectional study including a population-based sample of 1051 drivers aged 65 years and more. Visual trouble, Parkinson disease, dementia, and stroke history were associated with driving cessation. Future dementia was associated with self-reported crashes only. Attentional and executive deficits were associated with both outcomes. The detection of attentional and executive deficits should be included in driving evaluation procedures to improve awareness of these deficits by older drivers.

Tiring job and work related injury road crashes in the GAZEL cohort

The objective was to describe at-work and commuting crashes occurring in a cohort of French employees and to investigate occupational risk factors. The subjects were employees of the French national electricity and gas companies, Electricité de France and Gaz de France (EDF-GDF), who volunteered to join a research cohort (the GAZEL cohort which included 20,625 participants in 1989). Only crashes with injuries were considered. Crashes for the periods 1989--2001 were recorded together with the type of journey (commuting, work, private), the type of road-user, self-estimated responsibility, and injuries sustained by the subject. Annual incidences for gender/age groups and socio-occupational groups were computed for each of the two types of work related crashes. Occupational risk factor analyses were conducted using a Cox proportional hazards regression model with time-dependent covariates adjusting for the main confounders. A total of 146,285 person years at work were observed. Two indicators of self-reported work fatigue were associated with the occurrence of at-work crashes: "nervously tiring work" for males (RR=1.6, 95% CI [1.1; 2.3]), sustained standing for females (RR=3.0, 95% CI [1.0; 8.4]), adjusting for health status, location of residence, type of family, transport mode and mileage. As regards crashes while commuting, a self-reported uncomfortable position at work was a risk factor among women (RR=1.9, 95% CI [1.1; 3.3]). On the other hand, these occupational factors were not linked to road crashes in private trips. Work related road crashes seem then to be a matter for a specific prevention. Preventing employees from becoming exhausted should be considered as the first way to initiate such a prevention.

Actual incidences of road casualties, and their injury severity, modelled from police and hospital data, France

BACKGROUND

Nation-wide road casualty figures usually come from police data. In France, as in many developed countries, the reporting of fatalities is almost complete but the reporting of non-fatal casualties is rather low. It is moreover strongly biased. Valid estimates are needed.

METHODS

Using the capture-recapture method on police data and on a road trauma registry covering a large county of 1.6 million inhabitants, we estimate police under-reporting correction factors that account for unregistered casualties. These correction factors are then applied to the nation-wide police data, with standardization on under-reporting bias factors.

RESULTS

In 2004, whereas the police report 108,727 non-fatally injured, the estimation yields 400,200. Over the 1996-2004 study period, the average annual estimated incidence is 871/100,000 for all injured (3.4 times the police incidence), 232/100,000 for hospitalized, 103/100,000 for seriously injured (2.2 times the police incidence) and 12.6/100,000 for casualties with long-term major impairment. The incidence of seriously injured (NISS 9+) is 11.3/100,000 for pedestrians, 9.5/100,000 for cyclists, 36.3/100,000 for motorized two-wheel users and 42.5/100,000 for car users.

CONCLUSIONS

The estimated incidences are much higher than the police-based ones. This changes the scale of the road injuries issue. The risk of suffering a major impairment from a road crash is equal to the risk of being killed. Motorized two-wheel users experience a large burden of traffic casualties, much larger than that indicated by police data. The approach used can be reproduced in other countries, if an additional medical registration exists.

The impact of driver age on lost life years for other road users in France: A population based study of crash-involved road users

BACKGROUND

One of the concerns in road safety is the threat older drivers may pose to other road users. Using the rate of lost life years, the present study provides a public health approach to quantify this potential threat.

METHODS

A total of 1570686 motorised vehicle drivers or motorcycle riders and 652246 non-drivers, i.e. vehicle passengers, pedestrians and cyclists involved in injury crashes in France between 1996 and 2004, were included in a population based cross-sectional study. Fatality rates and rate of lost life years for each crash-involved driver age class were calculated for the drivers themselves and for other road users.

RESULTS

The study has shown a significant reduction in the rate of lost life years for crash-involved other road users (whether passengers, pedestrians, cyclists or opposing drivers) as driver age increases. Other road users lost half as many years of life when involved in crashes with drivers aged over 85 than with drivers under 65 (1.26 and 2.32 per 100 expected remaining life years, respectively).

CONCLUSION

Our findings suggest that among road users involved in injury crashes, older drivers are less dangerous for the other road users. By attributing other road users' lost life years to each driver age, this study represents a new contribution to the debate about ageing and road safety.

Cancer mortality in a synthetic spinning plant in Besançon, France

OBJECTIVES

To assess the mortality of a cohort of workers in a synthetic textile spinning plant and to evaluate the relationship between mortality from lung, liver and bladder cancer and the processes or the products used.

METHODS

The study population consisted of male workers present for at least 6 months in the plant from 1968 to 1984. The cohort was followed until 1999. Vital status and the causes of death were determined by consulting national registries. The population of the Franche-Comté region was used for comparison. In total, 17 groups of exposure were assessed by the industrial hygienist, based on the consensus of an expert group that determined the exposure levels of each job to selected occupational hazards. Each worker was assigned to one or several groups, according to his occupational history. Confounding factors could not be assessed. Standardised mortality ratios (SMR) and 95% bilateral confidence intervals were calculated based on an assumed Poisson distribution of the number of cases to compare the plant mortality and the population mortality. Internal analyses were performed with Cox models in order to assess the risks of death related to the various exposures.

RESULTS

In the whole cohort, mortality from all malignant neoplasms was lower than expected, but this was not significant. All the estimated SMRs were lower than or close to 1. The "hot -line fitters" (RR = 2.13; n = 9; 1.06 to 4.29) and the "fibre-drawing workers" (RR = 1.83; n = 20;1.09 to 3.07) experienced a statistically significant excess in mortality from lung cancer. A slightly elevated but not significant risk of death related to lung cancer (RR = 1.5; n = 41; 0.8 to 2.7) was observed in the groups with the highest exposure to mineral fibres. A statistically significant increase in cancer deaths was observed for workers with high exposure to dust (higher intensity: RR = 1.42; n = 79; 1.06 to 1.89).

CONCLUSION

Some findings, mainly of lung cancer, justify further exploration in other plants in this industry.

Attitudes associated with behavioral predictors of serious road traffic crashes: results from the GAZEL cohort

OBJECTIVES

To test the hypothesis that behavioral predictors of serious road traffic crashes (RTC) are correlated with unfavorable attitudes towards traffic safety.

DESIGN

Prospective and cross-sectional cohort study.

SETTING

France

PARTICIPANTS

13,447 of the 19,894 living members of the GAZEL cohort, workers and recent retirees of a French national utility company followed up since 1989.

MAIN OUTCOMES MEASURES

Driving behavior and attitudes towards traffic safety in 2001 by questionnaire. Serious RTCs were recorded over the subsequent 3 years using the cohort annual questionnaire. Behavioral predictors of serious RTCs were assessed using generalized linear Poisson regression models with time-dependent covariates. Factor scores extracted from the first four attitudinal factors of principal component analysis were saved and then regressed on behavioral predictors as independent variables.

RESULTS

After controlling for potential confounders, the best predictors of serious RTCs were: "exceeding speed limits on rural roads", "risky use of cellular phone", and "sleepy driving". The adjusted rate ratio ranged from 1.47 to 2.16. Predictors of contravention of the highway code (the first two predictors) were found to be strongly associated with negative attitudes towards "enforcement" and "speed limitations" with an adjusted odds ratio ranging from 1.31 to 2.02.

CONCLUSION

Our study supports the view that individuals with a high propensity for driving behaviors associated with an increased risk of RTCs were more likely to have negative attitudes towards traffic safety. Changing drivers' negative or distorted opinions of traffic "enforcement" as well as "speed limitations" and "alcohol prohibition on roads" could improve their compliance with road traffic rules.

Awareness of driving while sleepy and road traffic accidents: prospective study in GAZEL cohort

OBJECTIVES

To examine the association between self assessed driving while sleepy and the risk of serious road traffic accidents (RTAs).

DESIGN

Prospective cohort study.

SETTING

France.

PARTICIPANTS

13 299 of the 19 894 living members of the GAZEL cohort, workers and recent retirees of a French national utility company followed up since 1989.

MAIN OUTCOME MEASURES

Frequency of driving while sleepy in the previous 12 months, reported in 2001; rate ratios for serious RTAs in 2001-3, estimated by using generalised linear Poisson regression models with time dependent covariates.

RESULTS

The risk of serious RTAs increased proportionally with the frequency of self reported driving while sleepy. After adjustment for sociodemographic characteristics, driving behaviour variables, work conditions, retirement, medical conditions and treatments, depressive symptoms, and sleep disorders, the adjusted rate ratios of serious RTAs for participants who reported driving while sleepy in the previous 12 months "a few times" or "once a month or more often" were 1.5 (95% confidence interval 1.2 to 2.0) and 2.9 (1.3 to 6.3) respectively compared with those who reported not driving while sleepy over the same period. These associations were not explained by any reported sleep disorders.

CONCLUSIONS

Self assessed driving while sleepy was a powerful predictor of serious RTAs, suggesting that drivers' awareness of their sleepiness while driving is not sufficient to prevent them from having RTAs. Messages on prevention should therefore focus on convincing sleepy drivers to stop driving and sleep before resuming their journey.

Aggressive/hostile personality traits and injury accidents: an eight-year prospective study of a large cohort of French employees -- the GAZEL cohort

BACKGROUND

Aggressiveness on the roads and/or anger behind the wheel are considered to be a major traffic safety problem in several countries. However, the psychological mechanisms of anger and/or aggression on the roads remain largely unclear. This study examines a large cohort of French employees followed over the period 1994-2001 to establish whether psychometric measures of aggression/hostility were significantly associated with an increased risk of an injury accident (I-A). An I-A was defined as a traffic accident in which someone was injured, that is required medical care.

METHOD

A total of 11,754 participants aged from 39 to 54 years in 1993 were included in this study. Aggression/hostility was measured in 1993 using the French version of the Buss-Durkee Hostility Inventory (BDHI). Driving behaviors and I-A were recorded in 2001. Sociodemographic and alcohol consumption data were available from annual follow-up of the cohort. The relationship between aggression/hostility scores and I-A was assessed using negative binomial regression models with time-dependent covariates.

RESULTS

The overall BDHI scoring was not statistically predictive of subsequent I-A: adjusted rate ratio (aRR) 1.02, 95% confidence interval (CI) 0.81-1.28, for participants with intermediate scores and aRR 1.25, 95% CI 0.98-1.61 for those with high scores, both compared to those with low scores. The only BDHI subscales found to be associated with I-A were 'irritability' (aRR 1.33, 95% CI 1.02-1.75 for participants with high scores) and 'negativism' (aRR 1.32, 95% CI 1.01-1.71 for participants with high scores).

CONCLUSION

Overall aggression/hostility personality traits did not predict I-A in this large cohort of French employees, suggesting that aggressiveness on the roads and/or anger behind the wheel extend beyond the individual's general propensity for aggression.

Road mobility and the risk of road traffic accident as a driver. The impact of medical conditions and life events

STUDY OBJECTIVE

We conducted a longitudinal investigation of the impact of self-reported life events and medical conditions on changes in road mobility on the wheel between 2000 and 2002 in order to assess whether these changes would affect the risk of road traffic accident (RTA).

METHODS

Data are from a cohort of workers and retirees from the French national gas and electricity companies (the Gazel cohort). In the present study, 10,483 participants were included (7843 men aged 51-61 years and 2640 women aged 46-61 years, in 2000). The link between mobility and the risk of RTA was approximated using data on RTA number during lifetime and reported mobility in 2000. We then compared changes in road mobility between 2000 and 2002 resulting from life events and medical conditions reported to have occurred in the year 2001 or changed when compared to year 2000. We also compared road mobilities in 2000 in order to assess any pre-existing differences before life events and medical conditions. This led to estimation of the effect of road mobility changes on the risk of RTA.

RESULTS

Changes in road mobility associated with life events and medical conditions were only found among men. These changes in road mobility were minimal. Ensuing changes in the risk of RTA were estimated to be small (odds-ratios ranged from 0.94 to 1.01). The only life events found to be associated with increased road mobility was an important purchase. Hospitalization, serious RTA, and retiring were associated with reduced road mobility. Concerning medical conditions, men who reported cataract, angina pectoris, diabetes, anxiety and stress, sleep disorder, and depression decreased their road mobility.

CONCLUSION

We found no or moderate changes in road mobility resulting from life events and medical conditions, suggesting that results from previous published studies that assessed the impact of life events or medical conditions on RTA were not jeopardized by improper adjustment for road mobility.

Pain and pain treatment were associated with traffic accident involvement in a cohort of middle-aged workers

BACKGROUND AND OBJECTIVE

To assess the influence of medical conditions on road traffic accidents among a cohort of middle-aged workers and pensioners.

STUDY DESIGN AND SETTING

A longitudinal study of 13,548 participants from a cohort study of French workers. Follow-up data covered the 1989-2000 period. Adjusted hazards ratios (HR(adj)) for serious accidents were computed by Cox's proportional hazards regression with time-dependent covariates adjusted for age, occupation, annual mileage in 2001, alcohol consumption, and number of reported health problems.

RESULTS

Men who reported treated dental or gingival problems (HR(adj)=8.57, 95% confidence interval CI=2.70-27.2) and women who reported treated renal colic or kidney stones (HR(adj)=9.71, 95% CI=2.40-39.3) were much more likely to have a serious traffic accident. Treated glaucoma, hiatal hernia or gastric ulcers, and diabetes among women and treated cataract among men were also found to be associated with the risk of serious traffic accidents.

CONCLUSIONS

This study raises the hypothesis that pain and pain treatment (singly or in combination) could increase the risk of road traffic accident and confirms that medical conditions traditionally found to be associated with traffic accident involvement of older drivers are also risk factors for middle-aged drivers.

Type A behavior pattern, risky driving behaviors, and serious road traffic accidents: a prospective study of the GAZEL cohort

The type A behavior pattern (TABP), characterized by impatience, time urgency, and hostility, was originally developed in relation to coronary heart disease. Since 1986, there has been a debate on whether the TABP is also associated with risky driving behaviors leading to increased risks in road traffic accidents (RTAs). The authors examined prospectively the relation among risky driving behaviors, serious RTAs, and the TABP in a cohort of 20,000 French employees of Electricité de France-Gaz de France who were aged 39-54 years in 1993. A total of 11,965 participants were included in this study. The TABP was assessed in 1993 using the French version of the Bortner Rating Scale. Driving behaviors and serious RTAs were recorded in 2001. Sociodemographic and alcohol consumption data were available from the cohort's annual follow-up. The impact of the TABP on the risk of serious RTAs was assessed using the Cox proportional hazards regression model with time-dependent covariates. After adjustment for potential confounders, the risk for serious RTAs increased proportionally with TABP scores: hazard ratios were 1.29 (95% confidence interval: 1.03, 1.63) for intermediate-level scores and 1.48 (95% confidence interval: 1.16, 1.90) for high-level scores relative to low TABP scores. The authors concluded that type A drivers had an increased risk of RTAs. Implications of this finding for traffic safety are discussed.

Emotional Stress and Traffic Accidents

BACKGROUND

Personal responses to stressful life events are suspected of increasing the risk of serious traffic accidents.

METHODS

We analyzed data from a French cohort study (the GAZEL cohort), including a retrospective driving behavior questionnaire, from 13,915 participants (10,542 men age 52-62 years and 3373 women age 47-62 years in 2001). Follow-up data covered 1993-2000. Hazard ratios for serious accidents (n = 713) were computed by Cox's proportional hazard regression with time-dependent covariates. Separate analyses were also performed to consider only at-fault accidents.

RESULTS

Marital separation or divorce was associated with an increased risk of a serious accident (all serious accidents: hazard ratio 2.9, 95% confidence interval = 1.7-5.0; at-fault accidents: 4.4, 2.3-8.3). The impact of separation and divorce did not differ according to alcohol consumption levels. Other life events associated with increased risk of serious accident were a child leaving home (all accidents: 1.2, 0.97-1.6; at-fault accidents: 1.5, 1.1-2.1), an important purchase (all accidents: 1.4, 1.1-1.7; at-fault accidents: 1.6, 1.2-2.1), and hospitalization of the partner (all accidents: 1.4, 1.1-2.0).

CONCLUSION

This study suggests that recent separation and divorce are associated with an increase in serious traffic accidents.

Normes pour le MMSE, le test de rétention visuelle de Benton, le set test d’Isaacs, le sous-test des codes de la WAIS et le test de barrage de Zazzo chez des sujets âgés de 70 ans et plus : données de la cohorte PAQUID

Introduction. The aim of this study was to produce norms for the Mini-Mental State Examination, the Benton visual retention test, Isaacs's set test, the digit symbol substitution test and Zazzo's cancellation task (short 8-line version), in elderly people.

METHODS

Data was collected in a representative sample of 1780 subjects aged 70 years and older, followed-up for five years after inclusion in the PAQUID study. Only individuals who did not have characteristics likely to alter their cognitive performance were considered.

RESULTS

Descriptive statistics (median, tenth percentile, first and third quartile) were used to define gender-, age- and education-specific norms.

CONCLUSIONS

These norms can be used by clinicians to interpret a patient's performance on several widely used cognitive tests according to the scores obtained by individuals of the same age, gender and educational level.

Evidencing inhibitory deficits in Alzheimer's disease through interference effects and shifting disabilities in the Stroop test

To investigate the contribution of inhibitory deficits in the deterioration of executive function abilities in Alzheimer's disease (AD), a modified version of the Stroop test was submitted to 44 AD patients and 44 elderly controls. Half of the subjects performed successively the Interference Stroop task, the two control tasks and the Reverse Stroop task, and half performed the Reverse Stroop task, the control tasks and finally the Interference Stroop task. This experimental design allowed to assess inhibitory deficits by measuring classical interference effects but also by measuring the ability to shift between tasks instructions. Results confirmed AD patients' difficulty in suppressing the automatic response of reading in the Interference Stroop task. Moreover, AD patients presented worsened performances in the Interference task when administered after the Reverse task, and a Reverse Stroop effect was found in the patients revealing their difficulty in suppressing a previously relevant rule in order to learn a new one.

Traffic ticket fixing and driving behaviours in a large French working population

STUDY OBJECTIVE

The use of connections who have the authority to cancel penalties related to traffic violations seems to be very frequent in France. This study aimed at describing risk taking driving behaviours associated in France with using connections to have traffic tickets cancelled (ticket fixing).

DESIGN

Retrospective study on driving behaviour and road safety conducted between March and December 2001 within a cohort of French employees.

SETTING

France.

PARTICIPANTS

Employees of the French national utility company who have been followed up since 1989. The sample comprises 10 594 men aged 53-63 years and 3258 women aged 48-63 in 2001.

MAIN RESULTS

One third of the men and one fifth of the women reported that they had had a ticket fixed at some time. Those who reported having tickets fixed were more likely than the others to report high driving speeds (adjusted odds ratios (aOR) were 1.24, 1.52, and 1.66 in built up areas, on rural roads, and on motorways respectively), to report driving while under the influence (aOR = 1.39), and to report risky use of cellular phone while driving (aOR = 1.83). In addition, participants who reported having tickets fixed were more likely to have had at least one serious road traffic accident in the past 11 years (aOR = 1.21).

CONCLUSIONS

Indulgence and the use of connections are common practices in France. These results suggest that it is to confer a feeling of impunity that jeopardises efforts to combat unsafe driving. Abolition of these traditions is essential to ensure the credibility of preventive and repressive measures.

Différences entre les hommes et les femmes face au risque routier

BACKGROUND

In France 7,720 people were killed in traffic accidents in 2001, 75% of which were men; the number of injured people is estimated at 153,945, of which 65% were men. The objective of the study is to describe differences between males and females regarding accidents, and to explain the main reasons for these differences.

METHODS

Analysis is conducted from both national police data (2001) and data from the Rhone medical road accident trauma Register (1996-2001).

RESULTS

The male/female incidence rate is 3.1 for mortality (95% CI: 3.0-3.3) and 1.7 for morbidity (95% CI: 1.7-1.8). Two-wheel motorised vehicle accidents are very specific to males, which explains part of this overrepresentation. The fatality rate and the severe injuries rate among survivors are higher for males. This is true for every main user group (car users, motorised two-wheelers, cyclists, pedestrians) after adjusting for accident circumstances and age of casualties. Males are more severely injured for all body regions and have more often severe after-effects.

CONCLUSIONS

This paper shows the mechanisms leading to this unfavourable outcome for men. They correspond to differences in the number of trips, in the choice of road transport types, and moreover to differences in risk-taking behaviours. Underlying these behaviours, deep-rooted, strong and rather invariant differences between genders are to be found in the values associated with risk-taking on the road.

[Compliance in HIV infected adults. Study of opportunistic infection prophylaxis with cotrimoxazole in Ivory Coast]

BACKGROUND

The compliance to a daily treatment for illimited duration and the factors that influence it have been rarely studied in sub-Saharian Africa.

OBJECTIVE

Describe the compliance to prophylaxis with cotrimoxazole fort (one tablet per day) and its associated factors in patients infected by HIV participating in a clinical trial in Abidjan.

METHOD

The tablets packed in individual blisters were provided every month, and the blisters were recuperated the following month. A global compliance ratio (GCR) was established for each patient (empty blisters at the end of the study/follow-up period during the study) and monthly compliance ratio [MCR] (empty blisters during a visit/time lapse since last visit). For each monthly visit foreseen in the protocol, a respect of the appointment ratio (RAR) was described (visits foreseen in the protocol respected that month/visits foreseen in the protocol). The association of GCR with the characteristics on inclusion was studied using logistic regression methods.

RESULTS

530 adults were followed-up for a mean of 10 months. The MCR and the RAR progressed in parallel, decreasing the first 5 months and stabilizing at around 0.80 for the RAR and 0.70 for the MCR. The mean GCR was of 0.77. Three hundred and nine patients (58%) were considered as compliant (0.80<GCR<1). In multivariate analysis, those belonging to the group of compliers were associated with a paid occupation and with a past of tuberculosis, and was not associated with age, gender, level of education, nationality, civil status, number of persons in the home, proximity of a care center, clinical grade or CD4.

DISCUSSION

The estimated compliance was correct and stable. The association with a history of tuberculosis suggests that a person having already followed prolonged daily treatment would be more readily compliant to other long term treatments.

CONCLUSION

In Africa, cotrimoxazole is initiated long before the stage of antiretroviral treatment. The concern regarding the efficacy of such prophylaxis raises the question of compliance early on in the disease. This prepares the teams that organise the management of such patients to being faced with the problems of compliance to antiretrovirals.

Influence of education on the benton visual retention test performance as mediated by a strategic search component

Age-related cognitive decline has been reported by several studies. However, little investigations have dealt with the effect of education on this decline. In the present study, we examined the influence of educational level on visual working memory, evaluated by the Benton Visual Retention Test (BVRT in recognition format) in 829 elderly participants of the PAQUID study. A multivariate linear model suggested that the effect of education on BVRT performance was not mediated by visual discrimination abilities suggesting that it was mainly supported by better executive abilities. Moreover, the analysis of success and error location suggested that subjects with higher educational level use a more exhaustive exploration strategy during the recognition phase than subjects with lower educational level, which permit them to better perform. The ability of high educational level subjects to use more efficient strategies may participate to the 'cognitive reserve' capacity.

The effect of education on cognitive performances and its implication for the constitution of the cognitive reserve

Some studies have suggested that people with a high educational level have a lower risk of developing dementia compared to people with a low educational level. This protective effect of education has been explained by the constitution of a cognitive reserve which might delay the cognitive and functional expression of neurodegenerative illnesses. The aim of this study is, on the one hand, to evaluate the impact of education on cognitive functioning, which is thought to support the cognitive reserve capacity, and on the other, to determine the extent to which cognitive functioning is affected by other explanatory variables. The analysis was conducted on 1022 individuals without physical or neurological disorders in the Personnes Ages Quid study. These participants were aged 66 and over and had completed a neuropsychological battery. The effect of some demographic and socioeconomic variables on cognitive performance was also analyzed. Multivariate analysis showed a significant effect of education on most neuropsychological performances, independently of the other variables, and more particularly, in the high-attention-demanding tests. A principal component analysis demonstrated that education specifically increases 2 cognitive components: controlled processes and conceptualization ability. More-over, mental stimulation occurring after the education years, such as high-complex-activity occupations, seems to increase the controlled component. All these results suggest that the effect of education on cognitive reserve may be explained by an in-crease in controlled processes and conceptualization abilities. These 2 cognitive components might delay the clinical expression of neurodegenerative illnesses by maintaining global cognitive efficiency. Of these 2 components, controlled processes were also influenced by high attention-demanding occupations.

Executive function deficits in patients with dementia of the Alzheimer's type: a study with a Tower of London task

A growing number of studies report a deterioration of the executive function (EF) in dementia of the Alzheimer type (DAT). To evaluate EFs in DAT, a new version of the Tower of London (TOL) task, originally developed by Shallice (1982), was adapted. The new version of the test was built up in its easiest possible feature in order to be administrable to early- or middle-stage demented patients. Seventeen DAT patients, and 17 controls matched for age and sex, were administered the TOL. The protocol followed a "hierarchical paradigm," that is, simpler problems were embedded in more complex, subsequent problems. Results showed that DAT patients were impaired compared to controls. Both control and DAT groups showed a decrease in percentage of success rate in relation to the number of movements required by the task. On the more complex problems, the performance of DAT subjects was proportionally more impaired. Qualitative analysis revealed that rule breaking was a salient performance feature of the DAT group. These findings are consistent with the presence of an EF deficit in DAT.