What is Multi-Infarct Dementia?
Multi-infarct dementia (MID) is a neurological condition in which a series of small strokes over time causes progressive brain damage. The strokes cause a loss of blood flow to the brain, resulting in damage to and death of brain cells. This progressive damage ultimately produces the neurological symptoms of dementia.
Dementia is a general term for brain function changes resulting in problems with memory, thought processes, and behavior. The term is used to describe a cluster of symptoms that may be caused by several different diseases or disorders, as well as injuries or other neurological events such as strokes.
The most common type of stroke, an ischemic stroke, occurs when a blockage clogs an artery, starving the brain of oxygen and vital nutrients. When blood flow to the brain is suddenly disrupted, oxygen-starved tissue dies rapidly. Sudden confusion, visual disturbances, dizziness, an unusual headache, numbness, or weakness—especially on one side of the body—can signal the onset of a stroke.
The strokes that cause MID are sometimes so mild that they do not cause noticeable symptoms when they occur. As a result, doctors sometimes call these events “silent strokes.” However, the damage caused by the strokes is cumulative and eventually causes dementia symptoms.
Symptoms of MID
Common symptoms of MID include:
- Short-term memory loss
- Unusually rapid, shuffling gait
- Loss of bladder or bowel control
- Problems with focus or thought processes that interfere with tasks such as counting or following instructions
- Getting lost in familiar places
- Inappropriate emotional responses such as laughing or crying
Symptoms of dementia differ from case to case, but to be clinically diagnosed as dementia, symptoms must include significant impairment in at least two of these core brain functions:
- Memory. Sufferers often struggle with short-term memory loss, and memory loss becomes more severe as the disorder progresses. Dementia patients very often forget where they put things.
- Language. Those afflicted often have trouble communicating because they struggle to find the right words to express themselves. Communication problems also become more severe as the disorder progresses.
- Attention. Sufferers may have trouble concentrating or maintaining focused attention on a task or a subject. They may have difficulty planning or organizing their thoughts.
- Reasoning. Those afflicted are often unable to complete complex tasks or solve problems and may become confused or disoriented.
- Visual perception. Sufferers have trouble processing visual or spatial information and may become easily disoriented. This disorientation can lead to getting lost or not understanding where they are.
Dementia also often causes changes in behavior, including:
- Depression or anxiety
- Hallucinations, delusions, or paranoia
- Frustration or extreme agitation
- Inappropriate or irrational behavior
What Causes Multi-Infarct Dementia?
MID is a type of vascular dementia, the second-most common cause of dementia in older people. Vascular dementia happens when blood flow to the brain is disrupted, and MID is specifically caused by multiple strokes that produce cumulative damage to brain tissues.
A stroke is typically a quickly developing event caused by various underlying conditions. Therefore, it’s very difficult to predict when a stroke will occur or prevent it from happening once the conditions are in place. However, it is possible to identify some factors that put an individual at increased risk of having a stroke.
Risk factors for stroke
- Age 40 or over
- Heart disease
- High blood pressure (hypertension)
- High blood cholesterol levels
- Illegal drug use
- Recent childbirth
- Previous mini-stroke or transient ischemic attack (TIA)
- Inactive lifestyle and lack of exercise
- Current or past history of blood clots
- Family history of cardiac disease and/or stroke
Is Multi-Infarct Dementia Hereditary?
Vascular dementia is not heritable on its own, but the underlying cause of the dementia is often a condition such as heart disease or diabetes, which may have a family-history connection.
People at risk for a stroke often have a family history of:
- High blood pressure
- High levels of cholesterol, especially “bad” cholesterol or LDL
- High triglyceride values
- Inherited bleeding disorders
- Sickle cell disease
- Blockage in the neck or brain arteries
- An arteriovenous malformation (AVM), a tangle of abnormal blood vessels in the brain
How Is Multi-Infarct Dementia Detected?
Although some MID-related strokes may be mild, a stroke is a potentially life-threatening event requiring emergency medical attention. Brief episodes of numbness, weakness, or vision loss are urgent warning signs of a stroke. A transient ischemic attack (TIA)—a “mini-stroke”—often precedes a more serious cardiovascular event.
The acronym FAST is a reminder to take symptoms seriously. Each letter in the word stands for one of the things to watch for if a stroke is suspected:
- Face: Sudden weakness or drooping of the face and/or visual problems
- Arm: Sudden weakness or numbness of one or both arms
- Speech: Difficulty speaking and/or slurred speech
- Time: Time saves the brain. The sooner treatment begins, the better the chances are for recovery. Dial 9-1-1 to call an ambulance right away.
MID is progressive and incurable, but early detection of symptoms can allow you to get treatment that can improve your quality of life throughout the disease. The early indications of dementia include:
- Memory loss. Minor memory problems are a natural part of the aging process, but dementia-related memory loss typically includes forgetting names or dates, needing to be repeatedly reminded of the same things, and loss of memories that don’t come back.
- Problem-solving difficulties. These difficulties include having trouble doing tasks you used to have no problem with, such as following a recipe or paying bills on time. Problems with attention or concentration are also warning signs.
- Disorientation. People with dementia often have trouble remembering where they are or the day or date. They might get confused about the passage of time or have difficulty understanding spatial relationships.
- Visual perception. Dementia often manifests in difficulties with color or depth perception or other visual problems. These problems might show up while the sufferer is trying to read or drive.
- Language problems. Difficulty finding the correct words for a situation or participating in a conversation is a common early warning sign of dementia.
- Losing things. People with dementia often misplace everyday objects such as keys, glasses, and wallets.
- Poor judgment. People with dementia often make bad decisions about finances, social situations, grooming, or hygiene.
- Social struggles. People with dementia may also begin to avoid social situations because of their difficulties navigating them.
- Personality changes. Uncharacteristic, unexplained anxiety, frustration, confusion, or paranoia are common early signs of dementia.
How Is Multi-Infarct Dementia Diagnosed?
To pinpoint the cause of dementia symptoms, doctors look for a pattern of symptoms, risk factors, and family history. The diagnostic process typically includes physical examinations, tests, a review of medical and family history, and, often, information gathered from caregivers or loved ones. Some diagnostic procedures may be used to differentiate MID from dementia of another type. MID symptoms are often similar to those of Alzheimer’s, and some people have both MID and Alzheimer’s, making a definite diagnosis challenging.
Diagnostic steps may include:
- A physical exam. This exam aims to rule out specific physical conditions that could be causing the symptoms.
- Cognitive tests. These tests aim to measure the patient’s ability to think clearly, and they target cognitive functions such as memory, reasoning, language, attention, and orientation.
- Neurological tests. These tests measure the function of the patient’s nervous system. They evaluate functions such as balance, reflexes, memory, visual perception, and language.
- Brain scans. These tests, such as MRIs, CTs, and PET scans, look for signs of bleeding in the brain, stroke, tumors, or protein deposits characteristic of Alzheimer’s.
- Blood and laboratory tests. These tests will look at the patient’s blood chemistry for thyroid function issues, vitamin B-12 deficiency, or inflammation that may be causing the symptoms.
- Psychological assessments. These assessments may take the form of questionnaires or talk sessions with a mental health professional to look for signs of depression or other mental issues linked to the symptoms.
How Is Multi-Infarct Dementia Treated?
MID is not curable. No treatments have proven effective at slowing the disorder’s progression or reversing symptoms. Treatments are usually aimed at preventing future strokes, thus reducing the accumulation of brain damage. Other treatments may focus on lessening MID symptoms’ severity and improving quality of life as the disease progresses.
Non-drug therapies for treating dementia typically focus on making the sufferer’s environment as safe, comforting, and supportive as possible. Occupational therapy can be used to learn how to cope with the symptoms and progression of dementia. Modifications to the environment, such as increasing organization and decreasing distractions, can help the sufferer stay safe and calm.
How Does Multi-Infarct Dementia Progress?
The most common types of dementia, including that caused by Alzheimer’s, Lewy body dementia, vascular dementia, and frontotemporal dementia, all get worse over time as the damage to the sufferer’s brain increases. Different types of dementia progress at different rates. Vascular dementia, depending on the pattern of strokes, may progress quickly or slowly, and in late stages, it often closely resembles Alzheimer’s disease.
How Is Multi-Infarct Dementia Prevented?
The best strategy for decreasing the risk of MID is to make medical and lifestyle choices that reduce the risk of stroke. Preventive measures include:
- Take blood pressure medication as prescribed by your doctor.
- Control cholesterol levels with statin medications if prescribed by your doctor.
- Take anticoagulant drug therapy to prevent dangerous clotting if prescribed by your doctor.
- Make heart-healthy lifestyle changes, like eating a diet low in animal fat, losing weight, exercising, and quitting smoking.
- Treat type 2 diabetes. The disease more than doubles the risk of stroke.
- Drink only moderately. Excessive alcohol consumption dramatically increases the risk of stroke, particularly in women.
- Follow a healthy sleep routine. Sleep disorders are associated with an increased risk of stroke.
Multi-Infarct Dementia Caregiver Tips
Caring for someone with dementia is one of the most challenging responsibilities that any caregiver can face. Most caregivers are family members or loved ones. They are unprepared and untrained for the extremely difficult job of keeping the sufferer safe and as comfortable as possible as the disease progresses. If you’re responsible for taking care of a person living with dementia, keep these tips in mind:
- Learn as much as possible about the specific type of dementia to better understand what you’re facing now and what you’re likely to face in the future as the disorder progresses.
- Be as involved as possible with the sufferer’s medical care so that you can ask questions of doctors and other healthcare professionals.
- Don’t hesitate to ask for help from other family members or friends.
- Take advantage of support services in your community, such as respite care, if available.
- Don’t feel guilty if you feel frustrated or angry with the sufferer.
- Take time for yourself whenever possible, and don’t neglect your own emotional and physical needs.
- Find a support group for caregivers.
Multi-Infarct Dementia Brain Science
The brain is the most blood-hungry organ in the body, with a constant need for oxygen and other nutrients delivered through the bloodstream. When starved of blood, the fragile brain is vulnerable to damage ranging from speech difficulties to paralysis. As a result, one in four patients dies from their stroke during the first several days or weeks. In the case of MID, however, the strokes are not fatal, but damage to the brain is progressive.
Brain scientists are investigating what happens when blood rushes back into the brain after an ischemic stroke. Even after removing the clot, the brain releases a flood of inflammatory chemicals that damage the brain. New approaches aim to create a drug that could target the stroke site to stop immune cells from attacking vital brain tissue.
Multi-Infarct Dementia Research
Title: Rural Dementia Caregiver Project
Principal investigator: Veronica Yank, MD
University of California, San Francisco
San Francisco, CA
These caregivers are a vulnerable group due to their physical isolation and well-documented rural disparities in health care access and quality. In addition, many rural dementia caregivers experience serious health consequences due to caregiving responsibilities which can limit their ability to maintain their caregiving role. Thus, there is a pressing need for effective, scalable, and accessible programs to support rural dementia caregivers.
Online programs offer a convenient and readily translatable option for program delivery because they can be accessed by caregivers in the home and at the user’s convenience. For example, building Better Caregivers is an online 6-week, interactive, small-group self-management, social support, and skills-building workshop developed for caregivers of individuals with Alzheimer’s disease or related dementia.
The investigators will conduct a hybrid effectiveness-implementation randomized controlled trial that will enroll and randomize 640 rural dementia caregivers into two groups: the intervention (workshop) group and the attention control group. Caregivers will be recruited throughout the United States. Primary outcomes will be caregiver stress and depression symptoms. The investigators hypothesize that stress scores and depression symptoms will be significantly improved at 12 months in the intervention group versus the control group. The investigators will also identify key strengths (facilitators) and weaknesses (barriers) of workshop implementation. The investigators will use the RE-AIM implementation framework and a mixed methods approach to identify implementation characteristics pertinent to both caregivers and rural community organizations.
If the Building Better Caregivers workshop is proven to be effective, this research has the potential to open new research horizons, particularly on how to reach and effectively support isolated dementia caregivers in rural areas with a scalable intervention, even in low-resourced settings. If the workshop can achieve its goals with rural dementia caregivers, some of those most isolated, it would also be expected to be scalable in other low-resourced settings (e.g., in urban or suburban environments).
Title: Retina is a Marker for Cerebrovascular Heath
Principal investigator: Michelle Lin, MD, MPH
Mayo Clinic in Florida
Cerebral small vessel disease (SVD), present in 80-94% of adults over age 65, increases the risk of stroke by 2-fold, and dementia by 2.3-fold. Unfortunately, there is currently no treatment to slow SVD progression. This study aims to test whether impaired cerebral and retinal vasoreactivity may serve as a biomarker for SVD progression and to evaluate the safety and efficacy of cilostazol (an antiplatelet agent with vasodilatory and anti-inflammatory properties) for the treatment of SVD.
This is a prospective, observational nested pilot randomized controlled study to discover retinal biomarkers that would predict cerebral small vessel disease progression and evaluate the safety/efficacy of cilostazols in slowing SVD progression. Twenty CADASIL, 40 sWMD, 20 lobar CMB, and 20 age-matched healthy controls from the Mayo Clinic Florida Familial Cerebrovascular Disease Registry and neurology clinic will be recruited. All participants will undergo OCTA retinal scan, MRI-BOLD brain scan, cognitive battery evaluation, and blood sample at baseline and a 12-month follow-up visit. Key outcome measures are RVR, CVR, cognition, WMH volume, and CMB volume. The 40 patients diagnosed in the course of routine clinical care with sWMD will be randomized in a 1:1 ratio to receive cilostazol 100mg bid (or 50 mg bid if taking medications known to affect the metabolism of cilostazol) or no cilostazol and followed for WMD progression, and secondarily for changes in cognition, RVR, and CVR.
Title: Natural History Study of CADASIL
Principal investigator: Manfred Boehm, MD
National Institutes of Health Clinical Center
CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarct and leukoencephalopathy) is a genetic disorder. It causes the narrowing of the small blood vessels and can lead to strokes and dementia. Therefore, researchers want to monitor people with CADASIL over time.
This is a disease discovery/natural history protocol. We will enroll 100 CADASIL subjects to perform in-depth prospective and retrospective evaluations for research purposes. Some evaluations will be compared to healthy controls.
Primary Objective: This study will examine the pathogenesis and progression of CADASIL through comprehensive evaluations and molecular studies on biospecimens collected from affected individuals.
Secondary Objective: Comprehensive evaluations will be used to investigate the variability of the genotype and clinical phenotype of CADASIL during the study period.
Exploratory Objective: Healthy controls may be used for comparison for some of the research testing where data on normal values is lacking. Healthy controls will not be used to establish baseline range values but for qualitative comparison with the CADASIL population.