Stroke Rehabilitation, 1e 0323662080, 9780323662086

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Stroke Rehabilitation RICHARD WILSON, MD, MS Director Division of Neurologic Rehabilitation and Stroke Rehabilitation MetroHealth Rehabilitation Institute MetroHealth Medical Center Associate Professor Case Western Reserve University Cleveland, OH, United States

PREETI RAGHAVAN, MD Howard A. Rusk Associate Professor of Rehabilitation Research Vice Chair for Research Director Division of Motor Recovery Research Department of Rehabilitation Medicine New York University School of Medicine NYU Langone Health New York, NY, United States

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3251 Riverport Lane St. Louis, Missouri 63043

Stroke Rehabilitation Copyright Ó 2019 Elsevier, Inc. All rights reserved.

ISBN: 978-0-323-66208-6

No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/ permissions. This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein).

Notices Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds or experiments described herein. Because of rapid advances in the medical sciences, in particular, independent verifi cation of diagnoses and drug dosages should be made. To the fullest extent of the law, no responsibility is assumed by Elsevier, authors, editors or contributors for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein.

Publisher: Mica Haley Acquisition Editor: Kayla Wolfe Editorial Project Manager: Megan Ashdown Project Manager: Poulouse Joseph Designer: Alan Studholme

List of Contributors Bernadette Boden-Albala, MPH, DrPH Senior Associate Dean of Research and Program Development College of Global Public Health New York University New York, NY, United States Interim Chair Department of Epidemiology College of Global Public Health, New York University New York, NY, United States Professor Department of Neurology New York University Langone Medical Center New York, NY, United States Professor Department of Epidemiology and Health Promotion New York University College of Dentistry New York, NY, United States Li Khim Kwah, BAppSc (Phty), PhD Senior lecturer Discipline of Physiotherapy, Graduate School of Health University of Technology Sydney Sydney, NSW, Australia

Mira Goral, PhD Professor Speech Language Hearing Sciences The Graduate Center and Lehman College, CUNY Bronx, NY, United States Adjunct Professor MultiLing University of Oslo Oslo, Norway Peggy S. Conner, PhD Assistant Professor Speech-Language-Hearing Sciences Lehman College, City University of New York Bronx, NY, United States M. Gonzalez-Fernandez, MD, PhD Associate Professor Physical Medicine and Rehabilitation Johns Hopkins University School of Medicine Baltimore, MD, United States Managing Director Outpatient Rehabilitation Services Department of Physical Medicine and Rehabilitation Johns Hopkins University School of Medicine Baltimore, MD, United States

Associate Professor Health and Social Sciences Cluster Singapore Institute of Technology Singapore

Vice-chair for Clinical Operations Physical Medicine and Rehabilitation Johns Hopkins University School of Medicine Baltimore, MD, United States

Elizabeth E. Galletta, PhD Clinical Research Specialist NYU Langone Health New York, NY, United States

A.M. Barrett, MD Director Stroke Rehabilitation Research Kessler Foundation West Orange, NJ, United States

Clinical Assistant Professor Rehabilitation Medicine New York University School of Medicine New York, NY, United States Adjunct Professor Communication Sciences and Disorders New York University Steinhardt School of Culture Education, and Human Development New York, NY, United States

Research Professor Physical Medicine and Rehabilitation Rutgers New Jersey Medical School Newark, NJ, United States Chief, Neurorehabilitation Program Innovation Kessler Institute for Rehabilitation West Orange, NJ, United States v

vi

LIST OF CONTRIBUTORS

Richard Wilson, MD, MS Director Division of Neurologic Rehabilitation and Stroke Rehabilitation MetroHealth Rehabilitation Institute MetroHealth Medical Center Associate Professor Case Western Reserve University Cleveland, OH, United States Andrew K. Treister, MD Fellow, Neurocritical Care Department of Neurology Oregon Health and Science University Portland, OR, United States Preeti Raghavan, MD Howard A. Rusk Associate Professor of Rehabilitation Research Vice Chair for Research Director, Division of Motor Recovery Research Department of Rehabilitation Medicine New York University School of Medicine NYU Langone Health New York, NY, United States John J. Lee, MD PM&R Residency Program Director Cleveland Clinic Cleveland, OH, United States Gerard E. Francisco, MD Professor and Chair Department of Physical Medicine and Rehabilitation University of Texas Health Science Center (UTHealth) McGovern Medical School Houston, TX, United States NeuroRecovery Research Center TIRR Memorial Hermann Houston, TX, United States

Ricardo E. Jorge, MD Professor of Psychiatry and Behavioral Sciences Director Houston Translational Research Center for TBI and Stress Disorders Acting Director Beth K. and Stuart C. Yudofsky Division of Neuropsychiatry Michael E DeBakey VA Medical Center Baylor College of Medicine Houston, TX, United States Medical Director of TBI-Related Research Michael E. DeBakey VA Medical Center Professor of Psychiatry Baylor College of Medicine Houston, TX, United States John-Ross Rizzo, MD, MSCI Assistant Professor Rehabilitation Medicine NYU Langone Health New York, NY, United States Assistant Professor Neurology NYU Langone Health New York, NY, United States Steven R. Flanagan, MD Howard A. Rusk Professor and Chair of Rehabilitation Medicine Rehabilitation Medicine New York University Langone Health New York, NY, United States Michael J. Fu, PhD Research Assistant Professor Electrical Engineering and Computer Science Case Western Reserve University Cleveland, OH, United States Bioscientific Staff Physical Medicine & Rehabilitation MetroHealth System Cleveland, OH, United States

LIST OF CONTRIBUTORS Jayme S. Knutson, PhD Department of Physical Medicine & Rehabilitation Case Western Reserve University MetroHealth Rehabilitation Institute of Ohio MetroHealth Medical Center Cleveland Functional Electrical Stimulation Center Cleveland, OH, United States Lena Von Koch, Reg OT, PhD Professor Neurobiology, care sciences and society Karolinska Institutet Huddinge, Sweden Gunilla Margareta Eriksson, Reg OT, PhD Researcher Department of Neurobiology, Care Sciences and Society Karolinska Institute Stockholm, Sweden Researcher Department of Neuroscience Uppsala University Uppsala, Sweden Ulla Johansson, PhD Researcher Department of Occupational Therapy Neurobiology, Care Sciences and Society Stockholm, Sweden Abiodun Akinwuntan, PhD, MPH, MBA Dean and Professor School of Health Professions University of Kansas Medical Center Kansas City, KS, United States Joel Stein, MD Simon Baruch Professor and Chair Rehabilitation and Regenerative Medicine Columbia University College of Physicians and Surgeons New York, NY, United States Professor and Chair Rehabilitation Medicine Weill Cornell Medical College New York, NY, United States Physiatrist-in-Chief Rehabilitation Medicine New York-Presbyterian Hospital New York, NY, United States

vii

Scott Barbuto, MD, PhD Neurorehabilitation Research Fellow Physical Medicine and Rehabilitation New York Presbyterian Hospital MetroHealth Rehabilitation Institute of Ohio MetroHealth Medical Center Cleveland Functional Electrical Stimulation Center New York, NY, United States David A. Cunningham, PhD Department of Physical Medicine and Rehabilitation Case Western Reserve University Cleveland, OH, United States Lainie K. Holman, MD Staff Physician Pediatric Physical Medicine and Rehabilitation Cleveland Clinic Children’s Hospital for Rehabilitation Cleveland, OH, United States Clinical Assistant Professor Pediatrics Cleveland Clinic Lerner College of Medicine of Case Western Reserve University Cleveland, OH, United States Matthew A. Plow, PhD Frances Payne Bolton School of Nursing Case Western Reserve University Cleveland, OH, United States Sheng Li, MD, PhD Director, NeuroRecovery Research Center TIRR Memorial Hermann Research Center Professor Department of Physical Medicine and Rehabilitation University of Texas Health Science Center Houston McGovern Medical School Houston, TX, United States Jonathan Oen Thomas, MD Neurorehabilitation Fellow Physical Medicine and Rehabilitation Rutgers New Jersey Medical School Newark, NJ, United States Noa Appleton, MPH Department of Epidemiology College of Global Public Health New York University New York, NY, United States

viii

LIST OF CONTRIBUTORS

Benjamin Schram, BS Department of Epidemiology College of Global Public Health New York University New York, NY, United States

Heidi Fusco, MD Assistant Professor of Rehab Medicine RUSK Rehabilitation Ambulatory Care Center New York, NY, United States

N. Langton-Frost, MA, CCL-SLP, BCS-S Department of Physical Medicine and Rehabilitation Johns Hopkins University School of Medicine Baltimore, MD, United States

Hannes Devos, PhD Assistant Professor Department of Physical Therapy and Rehabilitation Science University of Kansas Medical Center Kansas City, KS, United States

M.N. Bahouth, MD Department of Neurology Department of Physical Medicine and Rehabilitation Johns Hopkins University School of Medicine Baltimore, MD, United States A.N. Wright, BS Department of Physical Medicine and Rehabilitation Johns Hopkins University School of Medicine Baltimore, MD, United States E. Karagiorgos, MS, CCC-SLP Department of Physical Medicine and Rehabilitation Johns Hopkins University School of Medicine Baltimore, MD, United States John Chae, MD, MS Professor and Chair MetroHealth Rehabilitation Institute MetroHealth Medical Center Department of Physical Medicine and Rehabilitation Department of Biomedical Engineering Case Western Reserve University Cleveland, OH, United States Melissa Jones, MD Faculty Psychiatrist Michael E. DeBakey VA Medical Center Assistant Professor of Psychiatry Baylor College of Medicine Houston, TX, United States Neera Kapoor, OD, MS, FAAO, FCOVD-A Clinical Associate Professor Rehabilitation Medicine NYU Langone Health New York, NY, United States

Kelsey A. PottereBaker, PhD Advanced Platform Technology Center Louis Stokes Cleveland Department of Veteran’s Affairs Department of Biomedical Engineering Lerner Research Institute Cleveland Clinic Cleveland, OH, United States Ela B. Plow, PhD, PT Department of Biomedical Engineering Lerner Research Institute Center for Neurological Restoration Department of Physical Medicine and Rehabilitation Neurological Institute Cleveland Clinic Cleveland, OH, United States Julia Chang, RN, BSN, SCRN, PhD Assistant Professor Frances Payne Bolton School of Nursing Case Western Reserve University Cleveland, OH, United States Eric Y. Chang, MD Restore Orthopedics & Spine Center Division of Pain Management Orange, CA, United States Yin-Liang Lin, PhD Department of Biomedical Engineering Lerner Research Institute Cleveland Clinic Cleveland, OH, United States

LIST OF CONTRIBUTORS Gert Kwakkel, PhD Professor Department of Rehabilitation Medicine Amsterdam Movement Sciences Amsterdam Neuroscience VU University Medical Center Amsterdam, The Netherlands

Janne M. Veerbeek, PhD Postdoctoral Research Fellow Division of Vascular Neurology and Neurorehabilitation Department of Neurology University Hospital and University of Zurich Zurich, Switzerland

Department of Physical Therapy and Human Movement Sciences Northwestern University Chicago, IL, United States

Cereneo Center for Neurology and Rehabilitation Vitznau, Switzerland

ix

Mahya Beheshti, MD Post-Doc Research Fellow, Rehabilitation Medicine, RUSK Rehabilitation, New York, NY, United States

Improving the Lives of Stroke Survivors

Stroke is a leading cause of serious disability, and the worldwide prevalence of stroke is expected to rise in the coming decades due to an aging population. The genesis of this book is an acknowledgment of the importance of stroke rehabilitation, as a field, in improving the lives of stroke survivors, and in contributing to population health. The goal of this book is to provide concise and practical guidance on the latest methods and concepts behind stroke rehabilitation necessary for rehabilitation providers to best serve their patients. The intended audience is physiatrists, trainee physiatrists, and other members of the rehabilitation team. Each chapter is authored by topic experts from diverse backgrounds and disciplines. We hope that this collective expertise will provide rehabilitation providers with a clear understanding of many topic areas to improve the lives of stroke survivors to the highest level of function and quality of life that can be achieved. We are thankful to all those who contributed to this book. We are grateful to the chapter authors, without whose expertise this book would not have been possible. We appreciate the staff at Elsevier who patiently guided

us through the process of editing this book and seeing it through to production. We hope this text is helpful in the treatment of your patients. Richard Wilson, MD, MS Director, Division of Neurologic Rehabilitation and Stroke Rehabilitation MetroHealth Rehabilitation Institute MetroHealth Medical Center Associate Professor Case Western Reserve University Cleveland, Ohio Preeti Raghavan, MD Howard A. Rusk Associate Professor of Rehabilitation Research Vice Chair for Research Director, Division of Motor Recovery Research Department of Rehabilitation Medicine New York University School of Medicine NYU Langone Health New York, New York

xi

CHAPTER 1

Stroke Epidemiology and Prevention BERNADETTE BODEN-ALBALA, MPH, DRPH • NOA APPLETON, MPH • BENJAMIN SCHRAM, BS

INTRODUCTION For many years stroke has been recognized as a leading cause of disability and mortality in the United States and other industrialized countries. Stroke is more disabling than fatal: the annual cost of direct and indirect stroke-related healthcare in the United States is estimated to be about 34 billion dollars measured in both healthcare dollars and loss of productivity.1 Over the last few years stroke has emerged as a major global burden as well, especially with the increase of risk factors such as hypertension, diabetes mellitus, and obesity, and a growing burden in low and middle income countries (LMICs), which are experiencing both chronic and infectious disease.2 Globally, the burden of stroke and other noncommunicable diseases is on the rise, and projections indicate they will continue to increase in prevalence, reaching epidemic proportions within the next decades.2 Awareness of the importance of stroke has led to a vast and accumulating literature on stroke risk factors, stroke etiology, and stroke outcomes. Stroke risk factors have been elucidated and clinical trials have indicated the benefits of treatment for persons with hypertension, atrial fibrillation, hypercholesterolemia, and asymptomatic carotid disease. In 1996, the first approved treatment for acute stroke, recombinant tissue plasminogen activator (rtPA), became available. Additionally, the pharmaceutical industry continues to actively pursue the development of “neuroprotective” agents to be used acutely for enhanced recovery from this disabling disease. Concurrently, over the last decade there has been important research looking at the contribution of devices, especially for clot retrieval, in the acute stroke period. In the 21st century, technological advancements in the field of brain imaging, genotyping, and medical information systems have begun to facilitate epidemiological study designs that can elucidate stroke risk markers at the molecular level and risk factors at the Stroke Rehabilitation. https://doi.org/10.1016/B978-0-323-55381-0.00001-9 Copyright © 2019 Elsevier Inc. All rights reserved.

subclinical level. Such advancements have provided researchers with more precision in stroke diagnosis and classification, including documentation and timing of events through the use of diffusion-weighted brain imaging techniques. Finally, as the relationship between genetic and environmental factors has become clearer, the role of precision medicine in prevention, treatment, and recovery has taken on a more central space.3 While improved technology has increased the precision and generalizability of data on stroke, epidemiologists who study stroke still struggle with critical issues. Despite recognition of and treatment modalities for modifiable stroke risk factors such as hypertension and cardiac disease, these risk factors remain highly prevalent. Additionally, overall stroke mortality rates are declining, but differentials continue to be reported between whites and other racial/ethnic groups including African-Americans, Hispanics, Alaska Natives, and Asian Pacific Islanders. In recent decades, the aging of the population and increasing prevalence of certain stroke risk factors have led to an increased absolute number of strokes per year (see Table 1.1), resulting in greater incidence, mortality, morbidity, and cost.2,4

CLINICAL DEFINITION OF STROKE A stroke is clinically defined as a focal neurologic deficit caused by a local disturbance in cerebral circulationd predominantly either an obstruction of cerebral blood (ischemic stroke) or a rupture to a vessel wall supplying blood to either the brain or spinal cord (intracerebral hemorrhage or subarachnoid hemorrhage, respectively). These three distinct etiological groupseischemic stroke (IS), intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH)dcomprise about 87%, 10%, and 3%, respectively, of all strokes annually.1 From an epidemiological perspective, the establishment of standardized practical diagnostic criteria for defining stroke is critical. Agreement on a definition

1

2

Stroke Rehabilitation TABLE 1.1

Absolute Number of Women and Men With Stroke (in Millions) in the World by Stroke Type in 1990 and 2013 (95% Uncertainty Limits Are in Brackets) 1990 Ischemic stroke

Incident

Hemorrhagic stroke

Prevalent

Women 2013

1990

Men 2013

2.14 (1.96e2.33)

3.28 (3.06e3.52)

2.17 (2.05e2.33)

3.62 (3.43e3.85)

Prevalent

4.86 (4.56e5.19)

8.66 (8.32e9.00)

5.18 (4.93e5.46)

9.65 (9.27e10.05)

Incident

0.86 (0.79e0.92)

1.53 (1.42e1.63)

1.03 (0.96e1.09)

1.84 (1.72e1.94)

1.78 (1.67e1.87)

3.36 (3.23e3.51)

2.11 (2.02e2.22)

4.00 (3.81e4.17)

Reprinted with permission from Feigin VL, Norrving B, Mensah GA. Global burden of stroke. Circ Res. 2017;120(3):439e448.

for stroke enables comparison of incidence and prevalence rates in studies throughout the world. A number of epidemiological issues arise in the enumeration of stroke cases. Diagnostic criteria for stroke and sensitivity of the diagnosis may differ from study to study. Indeed, early increases in stroke incidence may be attributed to the transition to universal use of CT imaging. Prior to the general use of CT imaging to confirm strokes, underdiagnosis or misclassification of strokes were more likely to occur. With better imaging and the ability to identify abnormalities associated with transient ischemic attack (TIA), we can move toward a more uniform definition of stroke overall. Over the years, there have emerged a number of different definitions of stroke and TIA. In 2013 the American Heart Association (AHA)/American Stroke Association (ASA) published a consensus statement, An Updated Definition of Stroke for the 21st Century, which incorporates clinical and tissue criteria.5 They defined central nervous system (CNS) infarction as “brain, spinal cord, or retinal cell death attributable to ischemia, based on neuropathological, neuroimaging, and/or clinical evidence of permanent injury.”5 Intracerebral hemorrhage and subarachnoid hemorrhage are also included in the broad definition of stroke. A TIA was originally defined as a neurological deficit lasting less than 24 hours. However, with the increased ability to image lesions with deficits lasting only a few hours, the AHA endorsed a revised, more operational definition of TIA as a “transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction.”6 After a TIA, risk of stroke is significant, particularly within the first year; 90day risk estimates are between 9% and 17%.7,8

The universal application of computed tomography (CT) brain imaging to confirm the presence of a lesion has been critical for early recognition and diagnosis of stroke. Magnetic resonance imaging (MRI) is also used increasingly in addition to CT to confirm stroke diagnosis. Typically stroke is still confirmed by CT with follow-up MRI often providing more information about the underlying etiology of the disease.

BURDEN OF STROKE The burden of stroke remains significant: approximately 795,000 people suffer and 130,000 die from either a first or recurrent stroke in the United States annually.10 Worldwide, there are over 10 million new strokes and 6.5 million stroke deaths each year, making stroke the second leading cause of death.2 Stroke mortality estimates are typically derived from national or local vital statistics data. Stroke data are obtained from sources that have used standardized classification systems such as the International Code of Diseases. Mortality rates from stroke have been on the decline in the United States and worldwide. The age-adjusted mortality rate for stroke declined almost 30% between 2004 and 2014 in the United States,1 although 1-year stroke mortality rates still exceed 20%.11 In highincome countries, the mortality rate has declined by 37% for ischemic stroke and 38% for hemorrhagic stroke between 1990 and 2010. In LMICs, mortality rates declined by 14% for ischemic and 23% for hemorrhagic stroke in the same time period.4 Although ischemic stroke accounts for the greatest public health impact because it occurs more frequently, hemorrhagic strokes are more fatal and thus also contribute significantly to the burden of stroke. The mortality rate for hemorrhagic

CHAPTER 1 stroke is estimated to be approximately 20% in high income countries and 62% in LMICs.4 Stroke mortality rates differ by country and geographic region (Fig. 1.1). According to 2013 data from the Global Burden of Disease Study, Russia and Kazakhstan had the highest reported ischemic stroke mortality rates and Western Europe, North and Central America, Turkmenistan, and Papua New Guinea had the lowest. For hemorrhagic stroke, the highest mortality rates were in Mongolia and Madagascar and the lowest were in North America, most of Western Europe, Australia, New Zealand, Russia, Iran, Saudi Arabia, Morocco, and Japan.12 There are also significant geographic disparities in stroke mortality within the United States, with an area of the southeast known as the “stroke belt” experiencing death rates approximately 20% higher than the rest of the country.13,14 In addition to the decline in stroke mortality, there has also been a steady decline in US age-adjusted stroke incidence rates over the past several decades,15e17 and globally among high income countries.4 Recent data from the Greater Cincinnati/Northern Kentucky study showed declining incidence of all strokes driven by a decrease in ischemic stroke in men.16 However despite these promising trends, there has been a rising incidence of stroke among younger populations, especially individuals 55 years and younger in the United States.18,19 A 2012 study using data from the US Nationwide Inpatient Sample revealed that although hospitalization rates for acute ischemic stroke decreased overall by 18.4% between 2000 and 2010, they actually increased 43.8% for individuals of ages 25e44 years.19 This trend is likely a result of the increasing prevalence of stroke risk factors in younger populations, including type 2 diabetes mellitus, hypercholesterolemia, obesity, and alcohol abuse.19 Younger individuals who suffer from a stroke face the potential of longer-term disability or greater years of potential-life-lost. Implementing early education and early prevention measures are, therefore, crucial in reducing the burden of stroke. Over the last few decades, a number of important studies have attempted to enumerate the incidence of stroke cases in the United States and other countries each year. Incidence estimates have been indirectly calculated using figures from smaller community samples to project national figures. In the United States, several early population-based studies from Framingham, Massachusetts,9 Rochester, Minnesota,20 and the Lehigh Valley, Pennsylvania/New Jersey,21 have contributed significantly to our knowledge about stroke trends, subtypes, risk factors, and incidence rates in men and women. Extensive stroke surveillance systems were

Stroke Epidemiology and Prevention

3

used to ascertain all incident stroke cases within a defined geographical area. Early incidence figures came from the Framingham Study, a large epidemiological study initiated in 1950 that is following 5000 men and women who were initially free of cardiovascular disease. This study indicated differences in stroke incidence by gender, with greater incidence rates among men than among women.9 Subsequent studies confirmed this finding, although recent evidence shows a narrowing of this gender gap in the United States.2,16,22 However, despite some evidence of higher stroke incidence rates in men, women have greater lifetime risk of stroke because they have a longer life expectancy.23 Despite the important contributions of these primarily white cohorts, their findings may not be generalizable to multiethnic populations. Studies have reported differences in stroke incidence between racial/ethnic groups, especially stroke incidence rates among blacks. The community-based Northern Manhattan Stroke Study (NOMAS) reported a 2.4-fold higher rate of first stroke among African-Americans and a twofold higher incidence of stroke among Hispanics than that for whites.24 Various other studies have found similar patterns of increased incidence in these groups.25,26 In recent years, a number of multiethnic cohort studies in the United States have helped elucidate racial/ethnic disparities in stroke. These studies include the Greater Cincinnati/Northern Kentucky Stroke Study (GCNKSS), the Brain Attack Surveillance in Corpus Christi (BASIC) Project, the Atherosclerosis Risk in Communities (ARIC) study, and the REasons for Geographic and Racial Differences in Stroke (REGARDS) study.27e30 The 2005e09 Alaska Native Stroke Registry (ANSR) also generated the first estimates of stroke incidence among Alaska Native adults, and found them to be lower or similar to other U.S. racial/ethnic minority groups.31 Knowledge about incidence differences across racial/ethnic groups may allow for the development of more effective targeted stroke prevention programs. While there have been major advances in the quality of studies aimed at enumerating stroke incidence and prevalence, a number of epidemiologic issues persist. Difficulty obtaining death certificates and inaccuracy of the diagnosis on death certificates continue to contribute to underreporting of stroke. Assessment of population data such as census data may not be accurate for underserved or minority populations such as blacks or Hispanics because undercounting is considerable. Studies have reported highly variable stroke rates for nonhospitalized cases. This variability in stroke

Stroke Rehabilitation

4

A

B

FIG. 1.1 Age-standardized stroke disability adjusted life years (DALYs) and mortality rates per 100,000 person-years in various regions of the world in 2013 (both sexes, all ages). (Reprinted with permission from Feigin VL, Norrving B, Mensah GA. Global burden of stroke. Circ Res. 2017;120(3):439e448.)

CHAPTER 1 admissions has led to difficulties in obtaining accurate incidence rates using hospital-based cohorts or stroke registries because of underreporting of mild or nonhospitalized cases of stroke. While this problem has decreased, this still contributes somewhat to error in accuracy of reporting.

PREVENTION In recent years, great strides have been made in understanding the pathophysiology of stroke and in developing treatments that reduce morbidity and mortality after stroke. The most effective way to reduce the burden of stroke, however, is through prevention. Stroke prevention strategies can occur at multiple stages: in the healthy, stroke-free population (primary prevention), among those who have developed recognizable risk factors and may have subclinical disease (late primary or early secondary prevention), and after the development of neurological symptoms of stroke or TIA (late secondary or tertiary prevention).

CLASSIFICATION AND DETERMINATION OF STROKE RISK FACTORS An understanding of stroke risk factors is essential for effective stroke prevention. Some factors are not modifiable and may be better characterized as risk markers, while others are amenable to behavioral, medical, or surgical modification. Risk markers may include age, gender, race/ethnicity, or heredity. The identification of genetic determinants for stroke would allow early identification of individuals with increased risk of stroke through genetic screening. Social factors have a huge impact on stroke prevention, treatment, and recovery. These include more traditional factors such as education, income/wealth, and access to care, but are not limited to these. Modifiable risk factors, on the other hand, may include environmental or even genetic exposures that, when modified, lead to reductions in the risk of stroke. Factors that may have both environmental and genetic links include hypertension and hyperlipidemia. Various biological and lifestyle risk factors that have been associated with increasing the risk of stroke include hypertension, diabetes, hyperlipidemias, physical inactivity, smoking, diet, sleep and alcohol use, as well as other newer factors. Strategies for effective modification of these factors include risk factor identification, goal attainment for risk control, compliance strategies, and continued follow-up. While each of these lifestyle factors is unique and important, they frequently occur in combination in the same individual

Stroke Epidemiology and Prevention

5

and together represent a heavy burden of increased stroke risk. Stroke risk factors have been identified through both case-control and cohort studies. In case-control studies, selection bias may lead to a collection of cases that do not adequately reflect all individuals with stroke and controls that are not representative of the general population. One solution is to use population-based study designs in which all the cases of stroke within a specific area are included and controls are randomly derived from the same community. In cohort studies, the attributable risk or etiologic fractionda measure of the proportion of cases explained or attributed to the exposuredcan be readily calculated. Prospective cohorts usually require systematic, lengthy follow-up after a baseline assessment. The clear advantage to cohort studies is the measurement of the exposure prestroke and the ability to determine the prevalence of the exposure in the general population; however, these studies are time-consuming and expensive and require large numbers of subjects. Experimental epidemiological studies such as randomized controlled clinical trials are the mainstay of demonstrating that modification of a risk factor can lead to a reduction in stroke risk. Subjects who exhibit the risk factor of interest are randomly assigned to an intervention or not and then followed for the occurrence of a specific outcome such as stroke. Randomization is used to help ensure that the groups are balanced for known and unknown confounders. While these studies can also be expensive and require large numbers of patients, they are essential to the development of evidence-based guidelines for stroke prevention. Both the consensus statement “Guidelines for the Prevention of First Stroke” supported by the National Stroke Association (NSA) and the American Heart Association (AHA) scientific statement “Guidelines for the Primary Prevention of Stroke” provide evidence-based recommendations for decreasing stroke risk that act as a template for risk factor reduction (Table 1.2).32 Lifestyle modifications to reduce stroke risk may present a great challenge in that social, behavioral, and cultural factors increase the complexity of the risk reduction strategy. It must remain the priority of health professionals to define and promote a lifestyle conducive to reducing blood pressure, controlling blood glucose, elevating high-density lipoprotein-cholesterol, increasing physical activity, evaluating alcohol use, and promoting the cessation of cigarette smoking.

Stroke Rehabilitation

6

TABLE 1.2

Modifiable Risk Factors, Prevalence, Relative Risk, and Management Recommendations for Stroke Risk Factor Hypertension

32e34

Diabetes32,34,35

Estimated Prevalence (%)

Estimated Relative Risk

29

2.0e5.0

Regular BP screening, weight control, limit salt intake, antihypertensive drug treatment, BP self-monitoring

1.5e3.0

Tight glucose control through diet, oral hypoglycemics, and insulin. Strict regulation of BP if hypertensive. Statin treatment, especially in those with additional risk factors

9.4

Dyslipidemia32,34

Management Recommendations

Elevated LDL (
130 mg/dL)

30.3

1.2e1.4

Low HDL38 (