A major contributor to this article appears to have a close connection with its subject.(July 2016) |
Vladimir Hachinski | |
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Personal details | |
Born | Zhytomyr, Ukrainian Soviet Socialist Republic, USSR |
Occupation | Neuroscientist |
Vladimir Hachinski is a Canadian clinical neuroscientist and researcher based at the Schulich School of Medicine and Dentistry at Western University. [1] He is also a Senior Scientist at London's Robarts Research Institute. [2] His research pertains in the greatest part to stroke and dementia, the interactions between them and their joint prevention through holistic brain health promotion. [3] He and John W. Norris helped to establish the world's first successful stroke unit at Sunnybrook Hospital in Toronto, [4] [5] and, by extension, helped cement stroke units as the standard of care for stroke patients everywhere. [6] [7] He discovered that the control of the heart by the brain is asymmetric, the fight/flight (sympathetic) response being controlled by the right hemisphere and the rest and digest (parasympathetic) response being controlled by the left hemisphere and damage to one key component (the insula) can lead to heart irregularities and sudden death. This discovery has added fundamental knowledge to how the brain controls the heart and blood pressure and lays the foundation for helping prevent sudden death. [8]
Hachinski has held many prominent positions in the global neurology community, including editor-in-chief of the journal Stroke the leading publication in the field and president of the World Federation of Neurology and founder of World Brain Alliance. He is a Fellow of the Royal Society of Canada (FRSC) and the Canadian Academy of Health Sciences (FCAHS), a Member of the Orders of Ontario and Canada, and the recipient of several national and international awards and recognitions for his research and advocacy.
Hachinski was born in Zhytomyr, Ukraine, the eldest of three children. He moved with his family to Caripito, Venezuela as a child. The family moved to Port Perry, Ontario, Canada thereafter. He graduated from Port Perry High School a year later at the top of his class . [9]
Hachinski received his MD in 1966 from the University of Toronto, [10] [11] and completed his residency in internal medicine and neurology in Toronto and Montreal, followed by a neurophysiology fellowship in Toronto. He received his formal accreditation in neurology as a Fellow of the Royal College of Physicians and Surgeons of Canada (FRCPC) in 1972. [10] From 1973-74, a research fellowship with the Ontario Department of Health brought him to a cerebrovascular laboratory at the National Hospital for Nervous Diseases in London, England, and then to the Department of Clinical Physiology at Bispebjerg Hospital in Copenhagen, Denmark. [9]
Following this, he returned to Toronto to take a staff position in the Department of Neurosciences at Sunnybrook Medical Centre, where he and Dr. John W. Norris established the MacLachlan Stroke Unit, Canada's first acute stroke unit. [4] [11] Hachinski remained at Sunnybrook until 1980, when he moved to London, Ontario to act as a neurology consultant for its major health centres: University Hospital, Victoria Hospital, St. Joseph's Hospital, and the London Psychiatric Hospital. He was hired concurrently as a professor at Western University (then called the University of Western Ontario). [10] During this time (and until 1990), he also acted as Director of the Investigative Stroke Unit at London's University Hospital.
In 1987, he earned a Master of Science degree from McMaster University in Hamilton, Ontario, studying in the Department of Epidemiology and Biostatistics with a focus on design, measurement, and evaluation. The University of London’s highest earned degree, Doctor of Science (in Hachinski's case, in medicine), was conferred upon him in 1988 for his “contributions to migraine, stroke, and dementia.” [10]
At the beginning of Hachinski's career, the view prevailed that most dementias were caused by hardened brain arteries (mental deterioration via cerebral atherosclerosis). Hachinski showed in 1975 that, in fact, only a small minority of dementias were so-caused, and that most were “multi-infarct dementias” — dementias caused by multiple, small, often imperceptible strokes. [12] The terms “vascular dementia” and “vascular cognitive impairment” would later be widely adopted to describe all cognitive impairments "with a vascular component" in order to distinguish them from primary degenerative dementia (i.e., Alzheimer disease and senile dementia) and to emphasize that they are preventable and treatable, insofar as their vascular causes (i.e., atherosclerosis, stroke, etc.) are treatable as well. [13] He has offered an explanation for the origin of some of these lesions and associated symptoms through his concept of ambibaric brain. He postulates that the brain has two complementary blood pressure systems, one high and one low and disturbances in each lead to different types of preventable lesions. [14]
At the time, the prevalent view that dementia ensued from the slow strangulation of the brain's blood supply by hardening of the arteries spawned a whole industry of brain vessel “vasodilators”. He showed that brain blood vessels in dementia were not “hardened” and that “vasodilators” were not only expensive but useless. He also developed an eponymic “ischemic score” that continues to be widely used to identify the vascular (treatable and preventable) component of dementia. [15] Successfully distinguishing between the two is tremendously important for patient prognosis, as treating the vascular causes of dementias can mitigate their effects. The scale is a prolifically cited tool, and has since been validated and optimized for use outside of clinical research settings. [16]
In 1986, the journal, Archives of Neurology published a series of papers by Hachinski, Harold Merskey and colleagues on the rarefaction of white matter in the brains of elderly people. These papers were among the first to recognize the importance of white matter lesions as risks for stroke and dementia. Rarefaction of white matter in the brain had already been shown to be correlated with a wide variety of health problems, but these papers were groundbreaking for two reasons especially: First, they introduced the term, “leukoaraiosis,” a word derived by Hachinski, Paul Potter and Harold Merskey to etymologically and Hippocratically describe the rarefaction; and second, they specifically highlighted a previously underappreciated relationship between vascular risk factors for cognitive impairment (i.e., treatable and preventable risk factors for both stroke and multi-infarct dementia) and leukoaraiosis. By coining “leukoaraiosis,” Hachinski drew medical practitioners’ attention to these white matter hypodensities in the brains of patients affected by small strokes. [17] [18] [19]
Hachinski continued to develop and promote his novel approach to dementia — viewing it as a product of preventable and treatable vascular problems, thus itself also amenable to prevention, delay, and mitigation — eventually coining it as the “vascular cognitive impairment approach” to dementias in 1994. [20] [21] This proactive and preventative, rather than solely retroactive and treatment-based approach included other novel coinages, such as “brain at risk,” describing patients without cognitive impairment but with risk factors for it. [22] [23] [24]
Even with these developments, available diagnostic criteria for dementias continued to present a challenge, as they were not able to capture the complex, interactive, and adaptive nature of brain pathologies leading to dementia. For this reason, in 2006, Hachinski decided to lead (with Gabrielle LeBlanc) the development of core common standards to describe the clinical, neuropsychological, imaging, genetic, and neuropathological features of cognitive impairment. This standardization has allowed for ongoing improvement of the diagnostic criteria with new knowledge, comparison of results from different studies, and analysis & meta-analysis using “big data” techniques. [25]
The MacLachlan Stroke Unit at Sunnybrook, Canada's first stroke unit (est. 1975), was almost 20 years ahead of its time; stroke units have been considered the most effective treatment for stroke patients of all ages, severities, and types only since the 1990s. [26] [27] Hachinski and Norris' early work with that unit and others helped to cement the importance of dedicated wards for stroke patient monitoring and treatment, but his research over the next 17 years also shaped how those treatments and monitoring methods are executed.
In 1986, while he was Director of the Investigative Stroke Unit at University Hospital in London, he developed (with Robert Coté), the Canadian Neurological Scale – a simple but systematic tool, usable by non-physicians for evaluating and monitoring the neurological status of patients with acute stroke. [28] Later, in 1992, he (with collaborators David Cechetto and Stephen Oppenheimer) began work to explore possible mechanisms for observed increases in catecholamines, cardiac enzymes, arrhythmias, and sudden death following acute stroke. This would eventually lead to the discovery that the insula of the brain is the mediator of these various cardiac complications. [3] [29] [30] [31] [32] Knowing this alters doctors to monitor the heart closely, to prevent sudden death.
The scientific bases for preventing stroke and dementia together have been summarized by an international panel of experts. [33] [34]
Since stroke, heart disease and dementia represent risks for each other and share the same risk and protective factors, he advocates preventing this “Triple Threat” together. [35]
He leads a multidisciplinary team studying for the first time together environmental, socioeconomic and individual risk and protective factors in the joint prevention of stroke, heart disease and dementia.
He is a participant in an initiative to make brain health the top priority. He has offered a definition of brain health based on the World Health Organization definition of health” “A state of complete physical, mental and social well-being through a full, balanced, continuous development and exercise of the brain [36] or in lay terms "Brain health is when thinking, feeling and connecting are the best that they can be in a sage, healthy environment."
In addition to his interest in the mechanisms of stroke and best practices for treatment, Hachinski also has a keen research interest in stroke prevention. He acted as the principal neurological investigator on several seminal, multicentre studies, beginning with the Canadian-American Ticlopidine study (1983–88) [37] [38] and the Extracranial/Intracranial Arterial Bypass Surgery trial (1983–87). The former showed a preventative advantage to the drug Ticlopidine over commonly-prescribed Aspirin, while the latter showed that the increasingly popular and very expensive EC/IC arterial bypass procedure did not significantly reduce the risk of ischemic stroke. [39]
In 2003, alongside several other researchers, Hachinski began a proof of principle study through the Canadian Stroke Network on secondary stroke prevention. The study aimed to explore the efficacy of stroke risk-factor counselling and monitoring in effecting lifestyle changes and prescription adherence in patients, as well as exploring barriers and testing possible solutions to effective stroke risk-factor management. [40] The preliminary results were extremely promising, showing that the addition of non-medical personnel to usual stroke care results in far better outcomes and reduced risk-factors. That initial study led to the creation of a multi-centre study in 2009 under the direction of Richard Chan. [41]
Hachinski's home province of Ontario, Canada introduced a formal Provincial Stroke System in 2000. [42] Hachinski advocates a strategy of preventing some dementias through the prevention of stroke. [43] With his colleagues, he showed, for the first time, a concomitant decrease in the incidence of stroke and dementia at a whole-population level. [44] He is leading a team from 5 Western University faculties, 5 provinces and 4 countries, to find out how and help apply the lessons widely.
He advocates and will help implement a new approach to the joint prevention of stroke, ischemic heart disease and dementia (the terrible three).
The new approach is based on these premises:
1. The “terrible three” inflict the highest number of death and disability adjusted life years (DALY’s) globally. However, they share the same treatable and preventable risk factors and represent risks for each other. Consequently, conditions that occur together should be prevented together.
2. To be effective prevention has to occur in “actionable units” small enough that their members have or can develop a sense of community.
3. The approach has to be:
a. Comprehensive – meaning that all relevant factors need to be considered: Environment, socio-economic factors and individual risk and protective factors
b. Customized – to address the main and manageable problems
c. Cost-effective – to justify why it should be done ahead of other priorities
This approach is known as the CCCAP or the 3C’s approach. [45]
Additionally, he advocates a change in strategy. Instead of using fear, warning people that if they don’t lead a healthy lifestyle they will suffer a stroke, heart disease or dementia decades later, the aim is to achieve brain/mental health now. [46]
Hachinski's primary popular medicine contributions have been publications in cooperation with his son, Vladimir, and daughter, Larissa. With Vladimir, he published an article in the Journal of the Canadian Medical Association called, "Music and the Brain" in August 1994. [56] With Larissa, he published the book, Stroke: A Comprehensive Guide to Brain Attack in 2003. Coining and employing the term “brain attack,” the book was written to increase public awareness of the importance of adequate stroke care and early intervention. [3] [11] [57]
An interest in the history of medicine has led Hachinski to publish several articles on the subject over the course of his career:
He possesses an honours degree in history from the University of London, UK, is a Corresponding Member of the North American Academy of the Spanish Language (a corresponding academy of the Royal Spanish Academy) [58] and has published a poetry anthology, Resonancias, [59] in Spanish under the pen name Alejandro Aranda. [11] In addition, "Dream Waltz," composed by Hachinski and orchestrated by Jason Stanford (Professor of Theory and Composition at Western University), premiered at the Musikverein in Vienna, Austria by the Brno Philharmoniker on September 24, 2013. [60] [61]
Over the course of his career, Hachinski has been the recipient of many awards and recognitions in his field. The most notable and significant are outlined below.
Hachinski holds four honorary doctorates. The first, Doctor of Medicine honoris causa from the University of Salamanca, Spain (the oldest university of the Spanish speaking world) was awarded in 2000. [79] This was followed by Doctor of the University honoris causa from the University of Buenos Aires, Argentina (2005), [80] [81] Doctor of Medicine honoris causa from the University of Cordoba, Argentina (2007), [82] and Doctor honoris causa from the Russian Academy of Medical Sciences (2012). [3] [83]
A transient ischemic attack (TIA), commonly known as a mini-stroke, is a temporary (transient) stroke with noticeable symptoms that end within 24 hours. A TIA causes the same symptoms associated with a stroke, such as weakness or numbness on one side of the body, sudden dimming or loss of vision, difficulty speaking or understanding language or slurred speech.
Dementia is a syndrome associated with many neurodegenerative diseases, characterized by a general decline in cognitive abilities that affects a person's ability to perform everyday activities. This typically involves problems with memory, thinking, behavior, and motor control. Aside from memory impairment and a disruption in thought patterns, the most common symptoms of dementia include emotional problems, difficulties with language, and decreased motivation. The symptoms may be described as occurring in a continuum over several stages. Dementia ultimately has a significant effect on the individual, their caregivers, and their social relationships in general. A diagnosis of dementia requires the observation of a change from a person's usual mental functioning and a greater cognitive decline than might be caused by the normal aging process.
Delirium is a specific state of acute confusion attributable to the direct physiological consequence of a medical condition, effects of a psychoactive substance, or multiple causes, which usually develops over the course of hours to days. As a syndrome, delirium presents with disturbances in attention, awareness, and higher-order cognition. People with delirium may experience other neuropsychiatric disturbances including changes in psychomotor activity, disrupted sleep-wake cycle, emotional disturbances, disturbances of consciousness, or, altered state of consciousness, as well as perceptual disturbances, although these features are not required for diagnosis.
Vascular dementia is dementia caused by a series of strokes. Restricted blood flow due to strokes reduces oxygen and glucose delivery to the brain, causing cell injury and neurological deficits in the affected region. Subtypes of vascular dementia include subcortical vascular dementia, multi-infarct dementia, stroke-related dementia, and mixed dementia.
Binswanger's disease, also known as subcortical leukoencephalopathy and subcortical arteriosclerotic encephalopathy, is a form of small-vessel vascular dementia caused by damage to the white brain matter. White matter atrophy can be caused by many circumstances including chronic hypertension as well as old age. This disease is characterized by loss of memory and intellectual function and by changes in mood. These changes encompass what are known as executive functions of the brain. It usually presents between 54 and 66 years of age, and the first symptoms are usually mental deterioration or stroke.
Cerebrovascular disease includes a variety of medical conditions that affect the blood vessels of the brain and the cerebral circulation. Arteries supplying oxygen and nutrients to the brain are often damaged or deformed in these disorders. The most common presentation of cerebrovascular disease is an ischemic stroke or mini-stroke and sometimes a hemorrhagic stroke. Hypertension is the most important contributing risk factor for stroke and cerebrovascular diseases as it can change the structure of blood vessels and result in atherosclerosis. Atherosclerosis narrows blood vessels in the brain, resulting in decreased cerebral perfusion. Other risk factors that contribute to stroke include smoking and diabetes. Narrowed cerebral arteries can lead to ischemic stroke, but continually elevated blood pressure can also cause tearing of vessels, leading to a hemorrhagic stroke.
Stroke is a medical condition in which poor blood flow to a part of the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functioning properly.
Henry Joseph Macaulay Barnett, known by his colleagues and friends as "Barney", was a Canadian physician and neurologist. He was also a leading clinical stroke researcher as a result of being the principal investigator in several major clinical trials. As a clinical scientist, he did pioneering research in stroke prevention, beginning with the use of aspirin.
Carotid artery stenosis is a narrowing or constriction of any part of the carotid arteries, usually caused by atherosclerosis.
Memory disorders are the result of damage to neuroanatomical structures that hinders the storage, retention and recollection of memories. Memory disorders can be progressive, including Alzheimer's disease, or they can be immediate including disorders resulting from head injury.
The prevention of dementia involves reducing the number of risk factors for the development of dementia, and is a global health priority needing a global response. Initiatives include the establishment of the International Research Network on Dementia Prevention (IRNDP) which aims to link researchers in this field globally, and the establishment of the Global Dementia Observatory a web-based data knowledge and exchange platform, which will collate and disseminate key dementia data from members states. Although there is no cure for dementia, it is well established that modifiable risk factors influence both the likelihood of developing dementia and the age at which it is developed. Dementia can be prevented by reducing the risk factors for vascular disease such as diabetes, high blood pressure, obesity, smoking, physical inactivity and depression. A study concluded that more than a third of dementia cases are theoretically preventable. Among older adults both an unfavorable lifestyle and high genetic risk are independently associated with higher dementia risk. A favorable lifestyle is associated with a lower dementia risk, regardless of genetic risk. In 2020, a study identified 12 modifiable lifestyle factors, and the early treatment of acquired hearing loss was estimated as the most significant of these factors, potentially preventing up to 9% of dementia cases.
Leukoaraiosis is a particular abnormal change in appearance of white matter near the lateral ventricles. It is often seen in aged individuals, but sometimes in young adults. On MRI, leukoaraiosis changes appear as white matter hyperintensities (WMHs) in T2 FLAIR images. On CT scans, leukoaraiosis appears as hypodense periventricular white-matter lesions.
Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens, and is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems with language, disorientation, mood swings, loss of motivation, self-neglect, and behavioral issues. As a person's condition declines, they often withdraw from family and society. Gradually, bodily functions are lost, ultimately leading to death. Although the speed of progression can vary, the average life expectancy following diagnosis is three to twelve years.
The Montreal Cognitive Assessment (MoCA) is a widely used screening assessment for detecting cognitive impairment. It was created in 1996 by Ziad Nasreddine in Montreal, Quebec. It was validated in the setting of mild cognitive impairment (MCI), and has subsequently been adopted in numerous other clinical settings. This test consists of 30 points and takes 10 minutes for the individual to complete. The original English version is performed in seven steps, which may change in some countries dependent on education and culture. The basics of this test include short-term memory, executive function, attention, focus, and more.
John David Spence is a Canadian medical doctor, medical researcher and Professor Emeritus at the University of Western Ontario. He is affiliated with the University of Western Ontario and the Robarts Research Institute, one of Canada's leading medical research organizations. Before his retirement from clinical practice in July 2022, he was also affiliated with the London Health Sciences Centre's University Hospital. He is a recognized expert in stroke prevention and stroke prevention research, with more than 600 peer-reviewed publications since 1970. He delivered more than 600 lectures on stroke prevention in 42 countries. In 2015, he received the Research Excellence Award from the Canadian Society for Atherosclerosis, Thrombosis and Vascular BiologyArchived 2016-10-05 at the Wayback Machine. In 2019, he was appointed a Member of the Order of Canada, and in 2020 he received the William Feinberg Award from the American Heart Association for excellence in clinical stroke research.
Arno Villringer is a Director at the Department of Neurology at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany; Director of the Department of Cognitive Neurology at University of Leipzig Medical Center; and Academic Director of the Berlin School of Mind and Brain and the Mind&Brain Institute, Berlin. He holds a full professorship at University of Leipzig and an honorary professorship at Charité, Humboldt-Universität zu Berlin. From July 2022 to June 2025 he is the Chairperson of the Human Sciences Section of the Max Planck Society.
Cerebrolysin is an experimental mixture of enzymatically-treated peptides derived from pig brain whose constituents can include brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF), and ciliary neurotrophic factor (CNTF). Although it is under preliminary study for its potential to treat various brain diseases, it is used as a therapy in dozens of countries in Eurasia.
Joel Salinas is an American-born Nicaraguan neurologist, writer, researcher, and an assistant professor of neurology at Harvard Medical School. He practices general neurology, with subspecialty in behavioral neurology and neuropsychiatry, at the Massachusetts General Hospital in Boston, Massachusetts. He is also a clinician-scientist at the Harvard T.H. Chan School of Public Health and the Framingham Study at the Boston University School of Medicine.
Miia K. Kivipelto is a Finnish neuroscientist and professor at the University of Eastern Finland and Karolinska Institute in Stockholm. Her research focuses on dementia and Alzheimer's disease.
Hypertension is a condition characterized by an elevated blood pressure in which the long term consequences include cardiovascular disease, kidney disease, adrenal gland tumors, vision impairment, memory loss, metabolic syndrome, stroke and dementia. It affects nearly 1 in 2 Americans and remains as a contributing cause of death in the United States. There are many genetic and environmental factors involved with the development of hypertension including genetics, diet, and stress.