Michel Bédard, PhD Canada Research Chair in Aging and Health Director, Centre for Research on Safe Driving Scientific Director, St.

Transcription

1 Michel Bédard, PhD Canada Research Chair in Aging and Health Director, Centre for Research on Safe Driving Scientific Director, St. Joseph s Care Group

2 CRSD mandate Our mandate is to contribute to the reduction of traffic related injuries by carrying out basic and applied research on processes that support safe driving, and developing interventions that promote road safety

3 Driving and aging: Emerging ethical issues 9 years ago!!!

4 In 2003 we needed answers to: When does driving becomes a safety issue? How do we find out? What do we do then? What is the impact of driving cessation, and how do we minimize it? TODAY???

5 Goal of this presentation Can crash risk be accurately estimated on the basis of group characteristics such as age or level of disability? Can crash risk be reliably measured for every individual person? Should this be routinely done? What should be the threshold of risk above which driving privileges are to be removed? What happens to older adults when the driving privilege is removed?

6 Deaths among motor vehicle occupants Ramage-Morin, 2008

7 Risk of a fatal injury* *Controlled for sex, BAC, site of impact, restraint use, traveling speed, vehicle model year, vehicle wheelbase (Bédard et al., 2002)

8 Should we be concerned about older drivers? The 2001 answer Age Fatalities data data 65+ data 0-29 trend trend trend Year

9 Should we be concerned about older drivers? The 2011 answer Number of Fatalities 30,000 25,000 20,000 15,000 10,000 <30 yrs: Projection <30 yrs: Data yrs: Projection yrs: Data 65+ yrs: Projection 65+ yrs: Data 5, Year

10 Unsafe actions by age Bédard, 2000

11 The driver domain Driver Cognition Physiology Beliefs/ Personality Knowledge/ Experience Attention Memory Senses Health Skills Confidence Training Experience

12 The driving task Strategic level Advanced decision making (e.g., choosing a route, staying home in bad weather) Requires a mix of judgement and memory Tactical level Decision making while driving (e.g., speed, distance between vehicles) Requires scanning of environment, awareness, and anticipation Operational level Actual maneuvers (e.g., turning, braking) Requires perception, ability to act adequately

13 Aging, health, and safe driving Reduced visual acuity Reduced hearing Slower reaction time Decline in attention/perception abilities Reduced ability to divide attention (e.g., cell phones) Reduced ability to attend to peripheral events Drivers often not aware of problem or too late to react Health conditions associated with risk of traffic violations and crashes

14 Prevalence of dementia Rises rapidly with age Less than 10 percent among those aged years More than 30% for those aged 85 years and over Main diagnoses: Alzheimer disease Vascular dementia (stroke) Dementia with Lewy bodies Fronto temporal dementia

15 Dementia and crash risk Exact crash risk difficult to establish Cannot conduct proper prospective studies; would require allowing individuals with dementia to drive without intervening even if crash probability is high Rely on weaker observational designs 5 times more at risk to have a crash Risk increases with dementia severity Some drivers with dementia are safe

16 On the issue of labels Does a diagnosis of cognitive impairment or reaching a certain age warrant driving cessation? Many individuals with a diagnosis of dementia (e.g., CDR = 1) and very old drivers pass current on road tests In some situations the cognitive impairment may be reversible or reduced (medication management, depression symptoms) Privilege should be based on capacity not on labels

17 Current approaches to identify unsafe drivers Self screening Self beliefs Screening tools Relatives/friends Health care professionals Screening tools Comprehensive evaluations

18 Perceived abilities (a few examples) Compared to other people your age, how likely are you to be in a car accident? Not as likely: 15 (39.5%) Just as likely: 23 (60.5%) More likely: 0 Compared to other drivers in your age group, how would you rate your driving abilities? A lot better: 49 (23.6%) Better: 84 (40.4%) Same: 71 (34.1%) Worse: 4 (1.9%)

19 Family/friends as evaluators Gradual decline Do not want to deprive drivers of privilege May be dependent on drivers for transportation May be overly concerned about lawsuits Disagreement among family members

20 Screening (triage) tests Many tests are statistically associated with driving outcomes (e.g., road test scores, past and future crashes) Some examples: Mini mental State Examination (MMSE) Clinical Dementia Rating (CDR) Trail making test (versions A & B) MVPT (motor free visual perception test) UFOV (Useful Field of View) UFOV considered the best by many

21 Properties of a good screening test Inexpensive Easy to administer Safe Has minimal discomfort High level of reliability and validity is the test consistently correctly identifying individuals with the condition and those without

22 Different worlds Theoreticians: academic researchers focused on development & testing of theories about how things work Typically report group level effects Practitioners: here, referring to clinicians making decisions about individuals fitness to drive (e.g., doctors, occupational therapists) Clinicians need fairly strong evidence that applies to individual patients or clients

23 How tall is the average person? Women my age: almost 5 5 Men my age: almost 5 10

24 Can you predict individual driving scores from one test? R 2 =.564, N = 38 Age < 55 years Age 55 years

25 All is not lost The two by two table Test Result Actual Fitness to Drive Unfit Fit Positive (unfit to drive) a = TP b = FP Negative (fit to drive) c = FN d = TN

26 Sensitivity Sensitivity* = the proportion who truly are UNFIT to drive that are correctly labeled as UNFIT by the test. * Calculated as a/(a+c) ; also known as the True Positive Fraction (TPF)

27 Specificity Specificity* = the proportion who truly are FIT to drive that are correctly labeled as FIT by the test. * Calculated as d/(b+d ); also known as the True Negative Fraction (TNF)

28 UFOV Divided Attention SMMSE Trails A # of prior driving offenses

29 Ethical issues The problem must be sufficiently important to justify screening (more so for mass than selective ) Do we have something to offer after screening? Using screening as triage Is the knowledge ready for application?

30 Science based tools Because someone says their tool is scientifically based it does not mean the methodology behind it was good! People do better the second time around Commercial interests may influence reporting of results

31 CIHR s definition of Knowledge Translation At CIHR, knowledge translation (KT) is defined as a dynamic and iterative process that includes synthesis, dissemination, exchange and ethicallysound application of knowledge to improve the health of Canadians, provide more effective health services and products and strengthen the health care system. irsc.gc.ca/e/39033.html

32 Graham et al.,

33 Knowledge inquiry Individual studies (the power of replication!) Quantity and diversity of source (not all from the same people) Implementation from single studies more prone to bias and random error Removes conflict of interest Continued evolution to meet the needs of end users

34 Synthesis Quality of evidence is paramount Appraisal, grading Systematic review, meta analysis Provide sufficient ground to warrant product/tool development Not every new knowledge should be translated Evidence may not be conclusive, or too early (exceptions may be where there are potential large benefits and little costs)

35 Products/tools Conduct review of proposed product/tool with end users E.g., guidelines, screening tools, training software Acceptability for end users Identify gaps, implementation challenges, etc.

36 Questions to help decide about the desirability of the adoption of preliminary research findings. Woloshin S, Schwartz L M JNCI J Natl Cancer Inst 2006;98:

37 Knowledge translation that isn t DriveAble, SIMARD MD and British Columbia DriveAble is a for profit service for which virtually no data on validity and reliability are available for public scrutiny The SIMARD MD was published in 2010 (Dobbs and Schopflocher (2010) Fail onroad Pass onroad * > ** * FP rate = 20% ** FN rate = 13%

38 Application of test results

39 KT is not: Commercialization (supply push model) Driven solely by researchers Rushed because of preliminary results

40 Screening programs for aging drivers are ethical if they: Consider end users Are based on a robust body of evidence Are not influenced by political pressure (or lobby) Result in more effective services and products Identify areas for improvement if possible Strengthen the transportation system Result in better outcomes for a large proportion of the target population

41 The big picture Test Result Actual Fitness to Drive Unfit Fit Positive (unfit to drive) Reversible? Remediation? Transition support? Mitigate? Compensate? Specificity? Negative (fit to drive) Sensitivity? Yeah? Pop.-based strategies? Training? Transition planning?

42 Ultimately Driving is a privilege mobility is a right Fair and transparent assessment process Transportation alternatives Maximizing independence and quality of life Health care professionals as advocates

43 Health care professionals Has the driver reached the minimum safety threshold accepted by society? Think in terms of the strategic, tactical, and operational levels using multi tiered approach Bordeline cases require considerable work

44 Physicians: Reluctant to report unsafe drivers (Jang et al., 2007) 78% state reporting negatively affect patientphysician relationship 75% state reporting has a negative impact on patients 60% state reporting has a negative impact on patients families Valid concern that patients will not see them if driving privilege is at risk (O Neil, 1996)

45 Physicians: Reluctant driving assessors (Jang et al., 2007) 89% stated they would benefit from more training 93% stated a tool to help them identify unsafe drivers would be useful Often refer for comprehensive evaluation

46 Comprehensive evaluations OT with specialized training Vision (e.g., acuity, contrast sensitivity) Physical (e.g., strength, ROM, coordination) Cognitive abilities (e.g., MMSE, MOCA, TMT, MVPT, UFOV, CDT) On road driving Other useful information: ADL Behavior problems Mood fluctuations when driving Previous incidents (reported and not) Simulator data

47 Some negative consequences of driving cessation Depression symptoms Happiness/life satisfaction Reduction in out of home activities Greater difficulty accessing health care May need to move Transportation needs assumed by family/friends

48 Driving is a privilege Mobility is a right Maximize independence and quality of life Ensure evaluation processes are fair and transparent Develop programs to improve driving Facilitate transition to non driving status Promote health care professionals as advocates Focused Research Can Help Us Achieve These Goals

49 Thank You! Supported by Canada Research Chair Program, Government of Canada Networks of Centres of Excellence (AUTO21) Canadian Institutes of Health Research (CIHR) Ontario Neurotrauma Foundation (ONF) Natural Sciences and Engineering Research Council (NSERC) Ontario Ministry of Energy, Science and Technology Canada Foundation for Innovation (CFI) Thunder Bay Community Foundation Lakehead University St. Joseph s Care Group

50 Some badly needed research Better tools and training for physicians and other health care professionals Better approaches to support safe driving (including commercialization of products) Better understanding of the impact of driving cessation Positive aspects Patients and family Transportation alternatives and urban planning

51 Candrive CIHR funded infrastructure grants ($1.25 million) ($5.56 million) Principal Investigators Malcolm Man Son Hing, MD Shawn Marshall, MD A nation wide network of inter disciplinary coinvestigators

52 Multi centre prospective cohort Canadian sites: Hamilton, Montreal, Ottawa, Thunder Bay, Toronto, Victoria, Winnipeg Australian and New Zealand sites Participants (N > 1,000) Regular drivers aged 70 or greater Measure their demographic, medical, functional, neuropsychological and driving characteristics Examined annually for 5 years

53 Candrive research objectives To understand the natural history of driving in older persons To address all health related aspects (psychosocial, cultural, linguistic, societal, legal, health care resource, political) of ensuring the safety for older drivers To find ways to extend the length of time that persons can drive Refresher programs Restricted licensing To develop a scientifically valid tool to support physicians in determining fitness to drive in aging persons

54 Putting the most recent CMAJ editorial in perspective Most older drivers are safe Most older drivers already self restrict Maybe at age 100?

55 Focus on sensitivity or specificity? Sensitivity Specificity Condition characteristics + Progression - + Mort./morb. - + Solution - - Cost of false label +