Risk Of Motor Vehicle Collision Research Articles

The impact of medical and non-medical prescription opioid use on motor vehicle collision risk

BackgroundProduction and distribution of prescription opioid analgesic drugs (POs) has increased immensely across the globe. Both medical (MPO) and non-medical (NMPO) use of opioid medication are associated with increased rates of morbidity and mortality, including possibly motor vehicle collisions. The current study examined data from a population-level survey to determine the impact of any PO, MPO, and NMPO use on collision risk. MethodsData were based on the 2010–2011 Centre for Addiction and Mental Health Monitor, a regionally stratified general-population telephone survey of adults (N=3428). Three binary logistic regressions of self-reported collision involvement in the previous 12months were conducted, each consisting of: (1) measures of demographic characteristics, driving exposure, and binge drinking; and (2) one of three measures of PO use (any PO use, MPO use, or NMPO use). ResultsAny PO use and MPO use were associated with increased collision risk (OR=1.60, CI=1.06, 2.40 and OR=1.62, CI=1.07, 2.45, respectively). The odds ratio for NMPO use did not reach statistical significance (OR=1.86, CI=0.91, 3.77, p=0.09). ConclusionsThese results suggested that doctor-prescribed PO use is associated with a 62% increase in collision risk. Although not a statistically significant finding, NMPO use may also be associated with increased collision risk. The magnitude of increased collision risk associated with PO use was comparable to that of driving after alcohol or cannabis use.

Assessment of patients' medical fitness to drive by primary care physicians: A cross-sectional study

ABSTRACTObjectives: Motor vehicle collisions (MVCs) are a significant health burden in Saudi Arabia. The literature has consistently indicated that chronic medical conditions, such as diabetes, heart disease, stroke, obstructive sleep apnea, and neurodevelopmental disorders, increase the risk of MVCs. Therefore, assessment of driver fitness by primary care physicians (PCPs) remains a major health intervention that might reduce MVCs. We studied the practices of PCPs in assessing medical fitness to drive in at-risk patients.Methods: We conducted a cross-sectional study of all 88 government-funded primary care centers in the city of Riyadh, Saudi Arabia. We administered a self-reported questionnaire to PCPs that inquired about their driving risk assessment for specific medical conditions.Results: Among all PCPs and centers, 189 PCPs (63%) from 74 centers (84%) participated in our survey. The mean age of the PCPs was 40 ± 10 years, and 108 (57%) were men. The average clinical experience of the group was 13 ± 9 years. Fewer than half of PCPs considered diabetes mellitus (45%) and obstructive sleep apnea (46%) as potential risks for MVCs. Approximately 45% of PCPs did not notify any authority or relatives of potential driving issues that they noticed in their patients. Only 15% of the participants believed that PCPs were responsible for alerting authorities about their fitness to drive.Conclusions: PCPs did not adequately assess their patients' driving history and eligibility. Efforts are needed to improve awareness among PCPs regarding the effects of chronic medical conditions on driving.

Frequency of extreme weather events and increased risk of motor vehicle collision in Maryland.

Previous studies have shown increased precipitation to be associated with higher frequency of traffic collisions. However, data regarding how extreme weather events, projected to grow in frequency, intensity, and duration in response to a changing climate, might affect the risk of motor vehicle collisions is particularly limited. We investigated the association between frequency of extreme heat and precipitation events and risk of motor vehicle collision in Maryland between 2000 and 2012. Motor vehicle collision data was obtained from the Maryland Automated Accident Reporting System. Each observation in the data set corresponded to a unique collision event. This data was linked to extreme heat and precipitation events that were calculated using location and calendar day specific thresholds. A time-stratified case-crossover analysis was utilized to assess the association between exposure to extreme heat and precipitation events and risk of motor vehicle collision. Additional stratified analyses examined risk by road condition, season, and collisions involving only one vehicle. Overall, there were over 1.28 million motor vehicle collisions recorded in Maryland between 2000 and 2012, of which 461,009 involved injuries or death. There was a 23% increase in risk of collision for every 1-day increase in extreme precipitation event (Odds Ratios (OR) 1.23, 95% Confidence Interval (CI): 1.22, 1.27). This risk was considerably higher for collisions on roads with a defect or obstruction (OR: 1.46, 95% CI: 1.40, 1.52) and those involving a single vehicle (OR: 1.41, 95% CI: 1.39, 1.43). Change in risk associated with extreme heat events was marginal at best. Extreme precipitation events are associated with an increased risk of motor vehicle collisions in Maryland.

Mechanisms behind distracted driving behavior: The role of age and executive function in the engagement of distracted driving

Performing secondary tasks, such as texting while driving, is associated with an increased risk of motor vehicle collisions (MVCs). While cognitive processes, such as executive function, are involved in driving, little is known about the relationship between executive control and willingness to engage in distracted driving. This study investigated the relationship between age, behavioral manifestations of executive function, and self-reported distracted driving behaviors. Executive difficulty (assessed with the BRIEF-A) as well as demographics (age and gender) was considered as possible predictors of engagement in distracted driving behaviors. Fifty-nine young, middle, and older adults self-reported executive difficulty and weekly engagement in distracted driving behaviors. Results revealed that while partially accounted for by age, global executive difficulty was uniquely related to engagement in distracted driving behaviors. Older age was associated with fewer weekly self-reported distracted driving behaviors while higher self-reported executive difficulty was associated with more frequent weekly engagement in distracted behavior. No significant differences were found between young and middle-aged adults on distracted driving behaviors. Findings conclude that distracted driving is a ubiquitous phenomenon evident in drivers of all ages. Possible mechanisms underlying distracted driving behavior could potentially be related to deficits in executive function.

Risk of motor vehicle collisions associated with medical conditions and medications: rationale and study protocol.

Medical conditions and medications may be associated with motor vehicle collisions (MVCs), which pose a major public health problem worldwide. Further epidemiological assessment is necessary for certain diseases and medications. Moreover, since disease aetiology and patterns of medication use may differ among ethnicities and healthcare systems, a population-specific approach is necessary. The present epidemiological study is designed to assess the medical conditions and medications associated with the risk of fatal MVCs among at-fault drivers in the Korean population. A retrospective cohort will be constructed for individuals who died in MVCs between 2005 and 2014 in the Korean Traffic Accident Analysis System database, which is linked to the Korean National Health Insurance database between 2002 and 2014. In order to compare medical conditions and medication use among drivers who died in a fatal MVC with the general population, standardised prevalence ratios will be calculated. In the culpability study, we will identify conditions and drugs associated with MVCs, comparing drivers with higher levels of responsibility to those with lower levels of responsibility. In the case-crossover study, the transient effects of medical conditions and medications will be examined using a conditional logistic regression model that adjusts for confounders. The results of this study will help to characterise the associations of diseases and medications with fatal MVCs in an Asian population, with the goal of informing regulatory and clinical decision-making regarding patients with the relevant conditions and the establishment of strategies for improving traffic safety.

Medication use and the risk of motor vehicle collisions among licensed drivers: A systematic review

ObjectivesDriving under the influence of prescription and over-the-counter medication is a growing public health concern. A systematic review of the literature was performed to investigate which specific medications were associated with increased risk of motor vehicle collision (MVC). MethodsThe a priori inclusion criteria were: (1) studies published from English-language sources on or after January 1, 1960, (2) licensed drivers 15 years of age and older, (3) peer-reviewed publications, master’s theses, doctoral dissertations, and conference papers, (4) studies limited to randomized control trials, cohort studies, case-control studies, or case-control type studies (5) outcome measure reported for at least one specific medication, (6) outcome measure reported as the odds or risk of a motor vehicle collision. Fourteen databases were examined along with hand-searching. Independent, dual selection of studies and data abstraction was performed. ResultsFifty-three medications were investigated by 27 studies included in the review. Fifteen (28.3%) were associated with an increased risk of MVC. These included Buprenorphine, Codeine, Dihydrocodeine, Methadone, Tramadol, Levocitirizine, Diazepam, Flunitrazepam, Flurazepam, Lorazepam, Temazepam, Triazolam, Carisoprodol, Zolpidem, and Zopiclone. ConclusionsSeveral medications were associated with an increased risk of MVC and decreased driving ability. The associations between specific medication use and the increased risk of MVC and/or affected driving ability are complex. Future research opportunities are plentiful and worthy of such investigation.

Obesity and trauma mortality: Sizing up the risks in motor vehicle crashes

Protective effects of safety devices in obese motorists in motor vehicle collisions (MVC) remain unclear. Aim of our study is to assess the association between morbid obesity and mortality in MVC, and to determine the efficacy of protective devices. We hypothesised that patients with morbid obesity will be at greater risk of death after MVC. A retrospective analysis of MVC patients (age ≥16 y.o.) was performed using the National Trauma Data Bank from 2007 to 2010. Patients with recorded comorbidity of morbid obesity (BMI≥40) were identified. Patients dead on arrival, with isolated traumatic brain injury, or incomplete data were excluded. The primary outcome was in-hospital mortality. Multivariate logistic regression was performed. Our sample of 214,306 MVC occupants included 10,260 (4.8%) morbidly obese patients. Mortality risk was greatest among occupants with morbid obesity (ORcrude 1.74 [1.54-1.98]). After adjusting for patient demographics, safety device and physiological severity, odds of death was 1.52 [1.33-1.74] times greater in motorists with morbid obesity. Motorists with morbid obesity were at greater risk of death if no restraint (OR 1.84 [1.47-2.31]), seatbelt only (OR 1.48 [1.17-1.86]), or both seatbelt and airbag were present (OR 1.49 [1.13-1.97]). No significant differences in the odds of death exist between drivers with morbid obesity and non-morbidly obese drivers with only airbag deployment (OR 0.99 [0.65-1.51]). Motorists with morbid obesity are at greater risk of MVC. Regardless of safety device use, occupants with morbid obesity remained at greater risk of death. Further research examining the effectiveness of vehicle restraints in drivers with morbid obesity is warranted.

Medication use and the risk of motor vehicle collision in West Virginia drivers 65 years of age and older: a case-crossover study.

BackgroundThe current generation of older adults reports a higher lifetime prevalence of prescription, over-the-counter, and recreational drug use. The purpose of this analysis is to characterize the drug usage and determine the risk of motor vehicle collision associated with individual medications in a population of drivers ≥65 years.MethodsA case-crossover study was conducted at West Virginia University Healthcare’s facilities using data obtained from the electronic health records (n = 611) of drivers ≥65 years admitted for medical treatment following a motor vehicle collision which occurred between Jan. 1, 2009 and June 30, 2014. Patients’ medication usage 14 days before collision were matched and compared to their medication usage during four control periods prior to collision. Odds ratios were then calculated for the most prevalent individual medications and pharmaceutical sub-classes using conditional logistic regression.ResultsAnalgesic, cardiovascular and gastrointestinal medicines were common. Few drivers tested positive for either licit or illicit drugs. Of those testing positive for drugs, benzodiazepines and opiates were prevalent. Drivers consuming Tramadol (adjusted OR 11.41; 95 % CI 1.27, 102.15) were at a significantly increased risk of motor vehicle collision.ConclusionsOlder adult drivers who have a prescription for this medication may need to be aware of the potential risk. Further research is necessary in a larger, more nationally representative population.

Zolpidem use and motor vehicle collisions in older drivers

ObjectivePrescription sleep medication use is most prevalent among women and older adults. Morning drowsiness and impaired coordination are side effects of sleep medications that may affect driving safety. The association between current use of zolpidem-containing medications and motor vehicle collisions (MVCs) was evaluated among drivers of advanced age. MethodsParticipants were current drivers aged ≥70 years residing in north-central Alabama, spoke English, had a valid driver's license, and had driven within the past three months (n = 2000). Current zolpidem use was determined by pill bottle review. The participant's five-year MVC history was determined from Alabama Department of Public Safety accident reports. The five-year MVC and at-fault MVC rate ratios (RR) were estimated comparing zolpidem users with nonusers in the overall sample and a priori–defined age and sex subgroups. ResultsThe unadjusted RR (95% confidence interval [CI]) of MVCs comparing zolpidem users with nonusers was attenuated after adjustment (1.46 [1.02–2.08] and 1.38 [0.97–1.98], respectively). Among women, the unadjusted and adjusted RRs (95% CI) were 1.65 (1.03–2.66) and 1.61 (1.00–2.60), respectively. The unadjusted and adjusted RRs (95% CI) among those aged 80 years or more were 2.24 (1.19–4.57) and 2.35 (1.20–4.61), respectively. There were no statistically significant associations among men or participants less than 80 years old. Similar patterns were present for at-fault MVCs. ConclusionCurrent zolpidem users, specifically women and individuals aged 80 years or more, had higher MVC rates than nonusers. Practitioners should consider behavioral treatment before initiating low doses of zolpidem and increasing it as needed to achieve restorative sleep in women and individuals aged 80 years or more to reduce the risk of zolpidem-associated MVCs.

Bicycle trauma and alcohol intoxication

IntroductionAs bicycling has become more popular, admissions after bicycle trauma are on the rise. The impact of alcohol use on bicycle trauma has not been well studied. The aim of this study was to examine the effect of alcohol intoxication on injury burden following bicycle-related crashes. MethodsA retrospective review of trauma patients presenting to a Level I trauma center after bicycle-related crashes from January 2002 to December 2011 was conducted. Demographics, injury data, alcohol intoxication, helmet use, and clinical outcomes were reviewed. Blood alcohol level (BAL) was considered positive if >0.01 g/dL. Variables were compared between patients based on BAL: negative, 0.01–0.16 g/dL, and >0.16 g/dL. ResultsDuring the 10 year study period, 563 patients met study criteria; mean age was 33.5 ± 16.5 years, 87% were male, and mortality was 1%. On average, bicycle crashes increased over the study period by 4.4 collisions per year. BAL was tested in 211 (38%) patients. Mean BAL was 0.24 g/dL, with 37% of these patients being intoxicated (BAL ≥0.010 g/dL). Intoxicated patients were significantly less likely to wear a helmet (4.7% vs. 22.2%, p = 0.002) and to be involved in motor vehicle crash (59.0% vs. 81.2%, p < 0.001). There was no difference noted in the injury burden including ISS ≥16 (14.3% vs. 19.5%, p = 0.335) and AIS Head ≥3 (17.9% vs. 21.8%, p = 0.502). When comparing patients according to their BAL, there was a decreasing risk of motor vehicle collision with increasing BAL (81.2% for undetected, 76.5% for BAL ≤0.16 g/dL and 54.1% for BAL >0.16 g/dL, p < 0.001). The risk for a severe head injury (AIS Head ≥3) was significantly lower in helmeted patients (8.4% vs. 15.8%, p = 0.035). ConclusionsThe incidence of bicycle-related crashes is increasing and more than a third of patients tested for alcohol after bicycle-related crashes are found to be intoxicated. The injury burden in intoxicated patients, including head trauma, was not different compared to non-intoxicated patients. In addition, the risk for a collision with a motor vehicle was significantly lower. Nonetheless, these patients rarely utilize a helmet. The findings from this study can be used for the development and implementation of preventive strategies to minimize the injury burden associated with bicycle crashes and intoxicated cyclists.

Predicting Risk of Motor Vehicle Collisions in Patients with Glaucoma: A Longitudinal Study.

PurposeTo evaluate the ability of longitudinal Useful Field of View (UFOV) and simulated driving measurements to predict future occurrence of motor vehicle collision (MVC) in drivers with glaucoma.DesignProspective observational cohort study.Participants117 drivers with glaucoma followed for an average of 2.1 ± 0.5 years.MethodsAll subjects had standard automated perimetry (SAP), UFOV, driving simulator, and cognitive assessment obtained at baseline and every 6 months during follow-up. The driving simulator evaluated reaction times to high and low contrast peripheral divided attention stimuli presented while negotiating a winding country road, with central driving task performance assessed as “curve coherence”. Drivers with MVC during follow-up were identified from Department of Motor Vehicle records.Main Outcome MeasuresSurvival models were used to evaluate the ability of driving simulator and UFOV to predict MVC over time, adjusting for potential confounding factors.ResultsMean age at baseline was 64.5 ± 12.6 years. 11 of 117 (9.4%) drivers had a MVC during follow-up. In the multivariable models, low contrast reaction time was significantly predictive of MVC, with a hazard ratio (HR) of 2.19 per 1 SD slower reaction time (95% CI, 1.30 to 3.69; P = 0.003). UFOV divided attention was also significantly predictive of MVC with a HR of 1.98 per 1 SD worse (95% CI, 1.10 to 3.57; P = 0.022). Global SAP visual field indices in the better or worse eye were not predictive of MVC. The longitudinal model including driving simulator performance was a better predictor of MVC compared to UFOV (R2 = 0.41 vs R2 = 0.18).ConclusionsLongitudinal divided attention metrics on the UFOV test and during simulated driving were significantly predictive of risk of MVC in glaucoma patients. These findings may help improve the understanding of factors associated with driving impairment related to glaucoma.

Recent trends in hospitalization and in-hospital mortality associated with traumatic brain injury in Canada: A nationwide, population-based study.

Traumatic brain injury (TBI) is the leading cause of traumatic death and disability worldwide.We examined nationwide trends in TBI-related hospitalizations and in-hospital mortality between April 2006 and March 2011 using a nationwide, population based database that is mandatory for all hospitals in Canada. Trends in hospitalization rates for all acute hospital separations in Canada were analyzed using linear regression. Independent predictors of in-hospital mortality were evaluated using logistic regression. Hospitalization rates remained stable for children and young adults but increased considerably among elderly adults (age Q65 years). Falls and motor vehicle collisions (MVCs) were the most common causes of TBI hospitalizations. TBIs caused by falls increased by 24% (p = 0.01), while MVC-related hospitalization rates decreased by 18% (p = 0.03). Elderly adults were most vulnerable to falls and experienced the greatest increase (29%) in fall-related hospitalization rates. Young adults (ages, 15Y24 years) were most at risk for MVCs but experienced the greatest decline (28%) in MVC-related admissions. There were significant trends toward increasing age, injury severity, comorbidity, hospital length of stay, and rate of in-hospital mortality.However, multivariate regression showed that odds of death decreased over time after controlling for relevant factors. Injury severity, comorbidity, and advanced age were the most important predictors of in-hospital mortality for TBI inpatients. Hospitalizations for TBI are increasing in severity and involve older populations with more complex comorbidities. Although preventive strategies for MVC-related TBI are likely having some effects, there is a critical need for effective fall prevention strategies, especially among elderly adults.

Inequity in health: older rural driving and dementia

The number of drivers with dementia is expected to increase exponentially over the coming decades. Most individuals with moderate-to-severe dementia (table 1) are unfit to drive.1 Drivers with moderate-to-severe dementia...

Recent trends in hospitalization and in-hospital mortality associated with traumatic brain injury in Canada: a nationwide, population-based study

Background: Traumatic brain injury (TBI) is the leading cause of traumatic death and disability worldwide. We examined nationwide trends in TBI-related hospitalizations and in-hospital mortality between April 2006 and March 2010 using a population-based database that is mandatory for all hospitals in Canada. Methods: Trends in hospitalization rates were analyzed using linear regression. Independent predictors of in-hospital mortality were evaluated using logistic regression. Results: Hospitalization rates remained stable for children and young adults, but increased considerably among elderly adults (ages 65 and older). Falls and motor vehicle collisions (MVCs) were the most common causes of TBI hospitalizations. TBIs caused by falls increased by 24% (p=0.01), while MVC-related hospitalization rates decreased by 18% (p=0.03). Elderly adults were most vulnerable to falls, and experienced the greatest increase (29%) in fall-related hospitalization rates. Young adults (ages 15-24) were most at risk for MVCs, but experienced the greatest decline (28%) in MVC-related admissions. There were significant trends towards increasing age, injury severity, comorbidity, hospital length of stay, and in-hospital mortality. However, multivariate regression showed that the odds of death decreased over time after controlling for relevant factors. Conclusions: Hospitalizations for TBI are increasing in severity and involve older populations with more complex comorbidities.

Binocular Visual Field Impairment in Glaucoma and At-Fault Motor Vehicle Collisions

To evaluate the association between the binocular visual field defects in drivers with glaucoma and the risk of motor vehicle collision (MVC) involvement. A retrospective cohort study was conducted on 438 drivers with glaucoma aged 55 years or older using data from 1994 through 2000. Demographic, clinical, and driving characteristics were obtained from chart abstractions and patient survey. Binocular field measures were generated by combining data from the monocular (central 24-degree radius) fields whereby the binocular field measure was defined as the more sensitive point at each monocular field location. Measures included threshold (TH), total deviation (TD), and pattern deviation (PD); severe impairment in these measures was defined as falling into the worst quartile. MVC data were obtained from police records. Rate ratios (RR) and 95% confidence intervals (CI) were calculated. Drivers with severely impaired PD measures were twice as likely to have an at-fault MVC compared with those not severely impaired (RR, 2.13; 95% CI, 1.21-3.75); those with severely impaired TH (RR, 1.49; 95% CI, 0.81-2.74) and TD (RR, 1.50; 95% CI, 0.82-2.74) also had an increased rate of at-fault MVCs, although these were not significant. When the binocular central visual field was stratified into 9 regions, drivers with impaired TH, TD, or PD had similarly elevated MVC rates in all regions compared with those not severely impaired, though not all reached statistical significance. On the basis of clinical measures of visual field routinely used in the management of glaucoma, drivers with glaucoma with severe PD field defects in the binocular field have a higher rate of at-fault MVC compared with those with less impaired or unimpaired binocular visual fields.

Obesity and vehicle type as risk factors for injury caused by motor vehicle collision

This study sought to describe variations in the risk of motor vehicle collision (MVC) injury and death by occupant body mass index (BMI) class and vehicle type. We hypothesized that the relationship between BMI and the risk of MVC injury or mortality would be modified by vehicle type. This is a retrospective cohort study of occupants involved in MVCs using data from the Crash Injury Research and Engineering Network and the National Automotive Sampling System Crashworthiness Data System. Occupants were grouped based on vehicle body style (passenger car, sport utility vehicle, or light truck) and vehicle size (compact or normal, corresponding to below- or above-average curb weight). The relationship between occupant BMI class (underweight, normal weight, overweight, or obese) and risk of injury or mortality was examined for each vehicle type. Odds ratios (ORs) adjusted for various occupant and collision characteristics were estimated. Of an estimated 44 million occupants of MVCs sampled from 2000 to 2009, 37.1% sustained an injury. We limited our analysis to injuries achieving an Abbreviated Injury Scale (AIS) score of 2 or more severe, totaling 17 million injuries. Occupants differed substantially in terms of demographic and collision characteristics. After adjustment for confounding factors, we found that obesity was a risk factor for mortality caused by MVC (OR, 1.6; 95% confidence interval [CI], 1.2-2.0). When stratified by vehicle type, we found that obesity was a risk factor for mortality in larger vehicles, including any-sized light trucks (OR, 2.1; 95% CI, 1.3-3.5), normal-sized passenger cars (OR, 1.6; 95% CI, 1.1-2.3), and normal-sized sports utility vehicles or vans (OR, 2.0; 95% CI, 1.0-3.8). Being overweight was a risk factor in any-sized light trucks (OR, 1.5; 95% CI, 1.1-2.1). We identified a significant interaction between occupant BMI class and vehicle type in terms of MVC-related mortality risk. Both factors should be taken into account when considering occupant safety, and additional study is needed to determine underlying causes of the observed relationships. Epidemiologic study, level III.

Medical Marijuana and Driving: a Review

Medical marijuana remains a highly debated treatment regimen despite removal of state penalties against care providers prescribing the drug and patients treated with the drug in many areas of the USA. The utility of marijuana in specific medical conditions has been studied at length, but its effects on driving performance and risk of motor vehicle collision remain unclear. As with other medications that affect psychomotor function, the healthcare provider should be informed of the potential risks of driver safety prior to prescribing this psychotropic drug to give appropriate anticipatory guidance for appropriate use. The goal of this narrative review is to assess the current literature regarding marijuana as it relates to driving performance and traffic safety. With a foundation in the pharmacology of cannabinoids, we consider the limitations of testing cannabinoid and metabolite concentration. In addition, we will review studies on driving performance and epidemiological studies implicating marijuana in motor vehicle collisions. The increasing prevalence of medical marijuana laws in the USA suggests that clinicians should be aware of marijuana's influence on public safety. Patients should abstain from driving for 8h if they achieve a subjective "high" from self-treatment with smoked marijuana and should be aware of the cumulative effects of alcohol and other psychoactive xenobiotics.

Potentially Driver-Impairing (PDI) Medication Use in Medically Impaired Adults Referred for Driving Evaluation

Potentially driver-impairing (PDI) medications have been associated with poorer driving performance and increased risk of motor vehicle collision. To describe the frequency of medication use and to determine the association between routine use of PDI medications and performance on driving and cognitive tests. A total of 225 drivers with medical impairment (mean age 68 ± 12.8 years, 62.2% male) were referred to an occupational therapy-based driving evaluation clinic. Medication lists were reviewed to identify PDI drugs, as defined by a previous study examining medications and crash risk. Outcome variables included road testing on the modified Washington University Road Test and cognitive scores on Trail Making Test Parts A and B, Snellgrove Maze Task, Clock Drawing Task, Driving Health Inventory (DHI) Useful Field of View, DHI Motor Free Visual Perceptual Test, Epworth Sleepiness Scale (ESS), Geriatric Depression Scale, and Functional Assessment Questionnaire. PDI medication use was documented in 68.9% of the sample, with the average subject taking 1.4 PDI drugs. Drivers taking routine PDI medications had a mean ESS score of 7.8 compared to 6.0 in the control group, suggesting increased somnolence (P = .007). Total number of routine medications, regardless of PDI designation, also correlated positively with ESS scores (P = .023). Use of PDI medications was associated with informant ratings of daytime drowsiness on the ESS, which has been linked to motor vehicle crash risk. Further investigation of individual drug classes is warranted using larger sample sizes and a high-powered study design.

Obstructive sleep apnea and driving: A Canadian Thoracic Society and Canadian Sleep Society position paper.

Untreated patients with obstructive sleep apnea (OSA) are at increased risk for motor vehicle collisions; however, it is unclear how this should be translated into fitness-to-drive recommendations. Accordingly, the Canadian Thoracic Society (CTS) Sleep Disordered Breathing Clinical Assembly and the Canadian Sleep Society (CSS) assembled a CTS-CSS working group to propose recommendations with regard to driving in patients with OSA. Recommendations for assessing fitness to drive in noncommercial drivers: 1. Severity of OSA alone is not a reliable predictor of collision risk and, therefore, should not be used in isolation to assess fitness to drive; 2. The severity of sleep apnea should be considered in the context of other factors to assess fitness to drive; 3. The decision to restrict driving is ultimately made by the motor vehicle licensing authority; however, they should take into account the information and recommendations provided by the sleep medicine physician and should follow provincial guidelines; 4. For patients prescribed continuous positive airway pressure (CPAP) therapy, objective CPAP compliance should be documented. Efficacy should also be documented in terms of reversing the symptoms and improvement in sleep apnea based on physiological monitoring; 5. For patients treated with surgery or an oral appliance, verification of adequate sleep apnea treatment should be obtained; and 6. A driver diagnosed with OSA may be recertified as fit to drive based on assessment of symptoms and demonstrating compliance with treatment. The assessment should be aligned with the provincial driver's license renewal period. Commercial vehicles: Assessment of fitness to drive should be more stringent for patients operating commercial vehicles. In general, the CTS-CSS working group was in agreement with the Medical Expert Panel recommendations to the Federal Motor Carrier Safety Administration in the United States; these recommendations were adapted for Canadian practitioners.

Association between vision impairment and driving exposure in older adults aged 70 years and over: a population‐based examination

To examine the relationship between vision impairment and driving exposure (amount of driving one does) in a population-based sample of older drivers and to examine to what extent cognitive status impacts this relationship. Enrollees consisted of a population-based sample of older adults from Alabama who were ≥70 years old, held a current driver's license, and had driven within the last 3 months. Three aspects of visual function were measured under binocular conditions - habitual distance visual acuity, contrast sensitivity and visual processing speed. General cognitive status was assessed with the mini-mental status examination. Driving exposure was estimated by the Driving Habits Questionnaire that asked about the number of miles, places, trips and days driven per week. Drivers with impaired contrast sensitivity exhibited reduced annual mileage, and a decreased number of places and trips driven per week compared to those with normal contrast sensitivity, even after adjustment for other factors. Slowed visual processing speed was associated with reduced number of days driven per week after adjustment. Visual acuity deficit was not associated with changes in driving exposure. Cognitive status did not impact any of the associations between vision impairment and driving exposure. Older drivers with contrast sensitivity impairment exhibit reduced driving exposure in terms of number of trips and places they drive per week, as well as decreased annual mileage. These apparent self-regulatory practices should be viewed as adaptive because contrast sensitivity impairment elevates motor vehicle collision (MVC) risk and reduction in driving exposure can reduce MVC risk.