Driving Performance of Older Adults with Early Dementia with Lewy Bodies or Early Alzheimer's ...

194 Pages·2014·3.55 MB·English

Driving Performance of Older Adults with Early Dementia with Lewy Bodies or Early
Alzheimer’s Disease

Stephanie Yamin

Thesis submitted to the
Faculty of Graduate and Postdoctoral Studies
In partial fulfillment of the requirements
For the Doctorate in Philosophy degree in Clinical Psychology

School of Psychology
Faculty of Social Sciences
University of Ottawa

© Stephanie Yamin, Ottawa, Canada, 2014
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ABSTRACT

Little is known about the specific cognitive impairments that may be the cause of the
reported increased crash rate in individuals with early dementia. Though, it is widely accepted
that attention, visuospatial and perceptual abilities are central in being able to operate a vehicle
safely. This study had three objectives. The first was to clarify the neuropsychological profile,
with an emphasis on attention, visuospatial and perceptual abilities, of individuals with early
dementia with Lewy bodies (DLB), the next was to examine the driving performances of two
groups of individuals with early dementia (i.e., early Alzheimer’s disease, AD, and early DLB)
and the last was to examine the degree of association between neuropsychological impairments
and driving impairments in hopes of predicting poor driving outcomes. Fifty-six participants
were recruited from three groups; 20 individuals diagnosed with early AD, 15 individuals
diagnosed with early DLB and 21 healthy age-matched controls. All participants were
administered the following neuropsychological tests: the Mini-Mental Status Exam (MMSE), the
Dementia Rating Scale (DRS-2), the Boston Naming Test (BNT), the Test of Everyday Attention
(TEA), the Visual Object and Space Perception Test (VOSP) and the Useful Field of View
(UFOV). Additionally, a simulated driving task was completed, with data being collected
through primary measures recorded by the simulator as well as an experimenter based driving
assessment using a demerit-point test. Results indicated that individuals with early DLB were
found to be most impaired in their visuospatial abilities, selective and divided attention abilities,
and were found to have significant cognitive fluctuations. Driving performances confirmed that
drivers with early dementia were at greater risk for motor vehicle collisions (MVC) and they
were found to commit a significant number of driving errors during the driving simulation.
Finally, this study was able to demonstrate that in drivers with early AD, attentional impairments
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were the strongest predictors of driving impairment, whereas in drivers with early DLB,
visuospatial impairments were indicative of driving impairment.
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TABLE OF CONTENTS
Abstract…………………………………………………………………………………………....1

List of tables…………………………………………………………………………………….....5

List of figures ……………………………………………………………………………………..6

Acknowledgements……………………………………………………………………………..…7

Introduction………………………………..………………………………………………………9

Driving in society……………………………………………………………………….…9

Collision risk…………………………………………………………………………..…11

Reasons for increased collision risk among older adults………………………………..16

Cognitive abilities involved in driving…………………………………………………..21

Michon’s model…………………………………………………………………21

Current licensing regulations in Canada…………………………………………………24

What is dementia and early stage dementia……………………………………………...26

A brief overview of Alzheimer’s disease………………………………………………...32

Brain pathology…………………………………………………………………..34

Clinical presentation and diagnostic criteria……………………………………..35

Neuropsychological profile of early AD…………………………………………38

A brief overview of dementia with Lewy bodies………………………………………...41

Brain pathology…………………………………………………………………..44

Clinical presentation and diagnostic criteria……………………………………..47

Neuropsychological profile of early DLB…………………………………….…50

Dementia and driving…………………………………………………………………….51

Research design……………………………………………………………………….…61

Methods…………………………………………………………………………………………..64
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Participants……………………………………………………………………………..64

Procedures………………………………………………………………………………..66

Primary outcome measures………………………………………………………………69

Results……………………………………………………………………………………………84

Section 1: Cognitive profile of older adults with DLB…………………………………..85

Section 2: Driving performances associated with early AD and early DLB…………….91

Section 3: Prediction of impaired driving in early AD and early DLB………………….97

Discussion…..…………………………………………………………………………………..113

Summary of results…………………………………………………………………..…115

Limitations……………………………………………………………………………...128

General conclusion……………………………………………………………………...132

References……………………………………………………………………………………....136

Appendices…………………………………………………………………………………..….171
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LIST OF TABLES
Table 1. One-way ANOVA Demonstrating that Groups are Matched for Age and Years of
Education.
Table 2. Chi-Square Demonstrating that Groups are Matched for Gender.
Table 3. One-way ANOVA between Controls and Early DLB Demonstrating Group
Composition.
Table 4. Chi-Square between Controls and Early DLB Demonstrating Group Composition.
Table 5. One-way ANOVA between Controls (Ctrls) and Early DLB on neuropsychological
tests.

Table 6. One-way ANOVA between Controls and Early AD Demonstrating Group Composition.
Table 7. Chi-Square between Controls and Early AD Demonstrating Group Composition.
Table 8. One-way ANOVA between Controls (Ctrls) and Early AD on measures of driving
performance.

Table 9. One-way ANOVA between Controls (Ctrls) and Early DLB on measures of driving
performance.

Table 10. One-way ANOVA between Controls (Ctrls) and Early AD on neuropsychological
tests.

Table 11. Correlation coefficients for neuropsychological test performance and impaired driving
performance for AD group.

Table 12. Correlation coefficients for neuropsychological test performance and impaired driving
performance for DLB group.

Table 13. Correlation coefficients between impaired neuropsychological test performance and
impaired driving performance for AD group.
Table 14. Correlation coefficients between impaired neuropsychological test performance and
impaired driving performance for DLB group.
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LIST OF FIGURES
Figure 1. Apparatus Setup for the Simulated Driving Task.
Figure 2. Scenario based on 12 kilometers of road in Thunder Bay, Ontario.
Figure 3. Scatterplot of performance on BNT and the demerit-point assessment for drivers with
early AD.
Figure 4. Scatterplot of performance on TEA8 and the demerit-point assessment for drivers with
early AD.
Figure 5. Scatterplot of performance on UFOV2 and the demerit-point assessment for drivers
with early AD.
Figure 6. Scatterplot of performance on TEA6 and Off-Road Accidents (ORA) for drivers with
early AD.
Figure 7. Scatterplot of performance on MMSE and the demerit-point assessment for drivers
with early DLB.
Figure 8. Scatterplot of performance on the DRS memory subtest and the demerit-point
assessment for drivers with early DLB.
Figure 9. Scatterplot of performance on the VOSP5 and the demerit-point assessment for drivers
with early DLB.
Figure 10. Scatterplot of performance on the VOSP Spatial Perception congregate score
(VOSP5-8) and the demerit-point assessment for drivers with early DLB.
Figure 11. Scatterplot of performance on the TEA1 subtest at 2 minutes and the demerit-point
assessment for drivers with early DLB.
Figure 12. Scatterplot of performance on the UFOV1 and the demerit-point assessment for
drivers with early DLB.
Figure 13. Scatterplot of performance on the VOSP5 and the Traffic Light Tickets for drivers
with early DLB.
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ACKNOWLEDGMENTS
I would like to thank a number of individuals that have been vital in accomplishing this
thesis. Foremost, I would like to express my sincere gratitude to my thesis advisor Dr. Sylvain
Gagnon for his continuous support of my Ph.D. study, research and personal development. His
patience, motivation, enthusiasm and knowledge have been imperative to this process. Similarly,
I would like to thank all of my lab mates in the Cognitive Aging Laboratory for their help and
support, and in particular, Dr. Arne Stinchcombe who assisted me in the logistics and set up of
this study. In addition to my advisor, I would like to thank the rest of my thesis committee: Dr.
Philippe Cappeliez, Dr. Patrick Davidson, and Dr. Claude Messier, for their encouragement,
insightful comments and at times tough questions. I would also like to outline the help and
contribution of Dr. Tim Aubry, who hired me as a research associate at the Centre for Research
on Educational and Community Services at the University of Ottawa, while I completed my
thesis dissertation. His help and support have also been crucial to my development throughout
this process.
I would also like to thank the staff at the Memory Disorders Clinic at Bruyère Continuing
Care. In particular, Dr. Inge Loy-English for her help in the early logistical planning of this
study. Dr. Andrew Frank for his continuous help, support and insightful comments throughout
the entire process of my Ph.D. study. Finally, I would also like to outline the help of Brenda
Landry-Czebruk, coordinator at the Memory Disorders Clinic, who provided imperative
functional support throughout the recruitment process and the study implementation. Without
their help this study could not have been possible and I am eternally grateful.
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In addition to help and support I have received from my academic life I have also
received a lot of help and support in my personal life. First, I would like to thank my husband
Marc for being a pillar of strength and support. His kind words, love as well as cheerleading
approach have encouraged me even in my darkest moments where I doubted myself. In addition,
the recent birth of our son, Henri, has not only been incredibly motivating in pushing me to
finish my thesis, but has also been an incredible adventure, where days are filled with love,
smiles and cuddles. I am thankful for the very close relationship I have with my brother Alex.
His presence and love have had a significant positive impact on my development. I would also
like to thank my parents-in-law, Michael and Margaret, for their constant support,
encouragement, and reminders to get my thesis finished! Finally, I’d like to thank my dearest
friends Arne and Dominique, with whom I have shared many delicious meals and laughs
throughout this demanding process.
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INTRODUCTION
Driving in our society.
Transportation is an essential need in our society that is tied to acquiring one’s essential
needs (i.e., shelter and food), maintaining successful employment, taking care of dependents and
much more. Transportation is also necessary for maintaining social interactions as well as having
a high quality of life (Steg & Gifford, 2005). In Europe, public transportation, walking and
bicycling are common traveling means. However, in Canada, Australia and the United States,
most transportation is completed by automobile, either as a driver or passenger (OECD, 2001).
In Canada, people spend approximately 60 to 80 minutes a day traveling and often make up to
three to four trips daily, and this time can increase substantially depending on the distance of a
home to the city centre (Environment Canada, 1996). Historically, our reliance on automobiles
has changed substantially with a sharp increase following WWII, due to lower fuel prices, higher
household incomes, smaller sized households, and women entering the workforce (Environment
Canada, 1996). This change is well illustrated in vehicle ownership records in Canada, which
indicates that in 1951 there were five individuals for every vehicle registered, whereas recent
estimates demonstrate that there are less than two individuals per registered vehicle (Statistics
Canada, 2006).
In Canada, as in most industrialized countries, there is a growing tendency for the
population to congregate in large city centres, where there is better access to public
transportation (OECD, 2001). Regardless of this trend, dependence on automobiles increased
between 1992 and 2005. In fact, the General Social Survey (2005) demonstrated that people aged
18 and over who used their automobiles exclusively for all of their transportation needs rose