Vascular dementia is an umbrella term that describes impairments in cognitive function caused by problems in blood vessels that feed the brain.

In some cases, a blood vessel may be completely blocked, causing a stroke. Not all strokes cause vascular dementia. It depends on the severity of the stroke, where the stroke occurred and the portion of the brain that's affected. Vascular dementia also can occur when blood vessels in the brain narrow, reducing the amount of blood flow to those sections of the brain.

The prevalence of vascular dementia ranges from 1 to 4 percent in people over the age of 65. Because few treatments are available for vascular dementia, prevention is crucial.

Vascular dementia symptoms can vary, depending on the portion of the brain that's affected. People with vascular dementia can experience:

• Confusion and agitation
• Problems with memory
• Unsteady gait
• Urinary frequency, urgency or incontinence
• Night wandering
• Depression
• A decline in the ability to organize thoughts or actions
• Difficulty planning ahead
• Trouble communicating details sequentially
• Memory loss
• Poor attention and concentration

Vascular dementia symptoms often begin suddenly and may worsen in a stepwise fashion, following a series of strokes or ministrokes. But some forms of vascular dementia develop gradually and can easily be confused with Alzheimer's disease.

Adding to the confusion, Alzheimer's disease and vascular dementia often occur together. In fact, some scientists believe that it's more common for these two disorders to occur together than apart.

Vascular dementia is most often caused by either a:

• Complete blockage of blood vessels in the brain. The complete blockage of an artery in the brain usually causes a stroke (infarction), but some blockages don't produce stroke symptoms. These "silent brain infarctions" increase a person's risk of vascular dementia. The risk increases with the number of infarctions experienced over time. One variety of vascular dementia is called multi-infarct dementia. Heart disease and irregular heart rhythms, such as atrial fibrillation, can increase your risk of stroke.
• Narrowing of the blood vessels in the brain. Vascular dementia also can occur without a complete blockage of an artery. Portions of the brain can be starved for oxygen and food by reduced blood flow from arteries narrowed by vascular disease.

Vascular dementia can also be caused by:

• Profoundly low blood pressure
• Brain damage caused by brain hemorrhage
• Blood vessel damage from such disorders as lupus erythematosus or temporal arteritis

Risk factors for vascular dementia include:

• Increasing age. This is one of the biggest risk factors for vascular dementia. The disorder is rare before the age of 65. And people in their 80s and 90s are much more likely to have vascular dementia than people in their 60s and 70s.
• History of stroke. The brain damage that occurs with strokes appears to increase the risk of developing dementia.
• Hardening of the arteries (atherosclerosis). Atherosclerosis occurs when plaque builds up in your arteries and narrows your blood vessels. This can increase your risk of vascular dementia.
• High blood pressure. Hypertension puts extra pressure on blood vessels throughout the body. This increases the risk of vascular problems in the brain.
• Diabetes. High glucose levels damage blood vessels throughout the body, increasing the risk of stroke and other vascular problems in the brain.
• Smoking. Smoking increases the risk of hardening of the arteries and other vascular diseases, including vascular dementia.
• High cholesterol. High levels of bad cholesterol (LDL) are associated with an increased risk of vascular dementia, and possibly with a higher risk of Alzheimer's disease.

You may first be seen at the hospital if you've had a stroke. Or, if your symptoms are mild, you may start by first seeing your family doctor or a general practitioner. However, you'll likely be referred to a doctor who specializes in disorders of the nervous system (neurologist).

Because appointments can be brief, and there's often a lot of ground to cover, it's a good idea to be well prepared for your appointment. Here's some information to help you get ready, and what to expect from your doctor.

What you can do

• Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
• Write down key personal information, including any major stresses or recent life changes.
• Make a list of all medications, as well as any vitamins or supplements, that you're taking.
• Ask a family member or friend to come with you, if possible. It can be difficult to recall all the information provided to you during an appointment. Someone who accompanies you may remember something that you missed or forgot.
• Write down questions to ask your doctor.

Your time with your doctor is limited, so preparing a list of questions ahead of time will help you make the most of your time together. List your questions from most important to least important in case time runs out. For vascular dementia, some basic questions to ask your doctor include:

• What's the most likely cause of my symptoms?
• Are there other possible causes for my symptoms?
• What kinds of tests do I need? Do these tests require any special preparation?
• Is this condition temporary or long-lasting?
• What treatments are available, which do you recommend and will they interact with my other medicine?
• What types of side effects can I expect from treatment?
• What's my prognosis?
• How quickly will I lose my memory?
• Will I need nursing home care?
• Are there any alternatives to the primary approach that you're suggesting?
• I have other health conditions. How can I best manage them together?
• Are there any brochures or other printed material that I can take home with me? What Web sites do you recommend?
• Is there any increased risk to my children?

In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.

What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on. Your doctor may ask:

• When did you first begin experiencing symptoms?
• Did your symptoms begin abruptly or slowly?
• Have your symptoms been continuous or occasional?
• Do you have a history of high blood pressure, elevated cholesterol, diabetes, heart disease or stroke?
• What were your first symptoms?
• Have other symptoms occurred since the first set of symptoms occurred?

If vascular dementia is suspected, your doctor may recommend one or more of the following tests:

• Computerized tomography (CT). A CT scan uses special X-ray equipment to produce a cross-sectional image showing a slice of your body's organs and tissues. A contrast material may be injected to help highlight any abnormalities in your brain's blood vessels.
• Magnetic resonance imaging (MRI). An MRI scan uses radio waves and a strong magnetic field to produce detailed images of internal organs and tissues. In some cases, contrast material may be injected to produce even more detailed pictures. Some people experience a feeling similar to claustrophobia when they're inside an MRI machine. If you think this will be a problem, your doctor can prescribe medication to help you relax.
• Positron emission tomography (PET). During a PET scan, you'll be injected with a low-level radioactive material, which binds to chemicals that travel to the brain. You lie on a table while an overhead scanner tracks the radioactive material. This helps show which parts of your brain aren't functioning properly. The test is painless and can be particularly useful in distinguishing between different types of dementia.
• Doppler ultrasound. Doppler ultrasound uses high-frequency sound waves to measure the direction and speed of blood cells as they travel through blood vessels — such as the carotid arteries, which travel through either side of your neck to connect your heart and brain. A Doppler ultrasound of your carotid arteries can help your doctor determine if there are blockages or narrow places impeding blood flow to your brain.
• Neuropsychological tests. Neuropsychological tests assess orientation, learning, recall, attention, calculation and language. Exam results for people with vascular dementia typically show the same types of cognitive deficits as the exam results of people who have Alzheimer's disease. One major difference, however, is in memory function. Most people with vascular dementia don't experience memory problems until later in the course of the disease unless there is a stroke in the exact area of the brain that controls memory.

There is no cure for vascular dementia and no drugs have been approved by the Food and Drug Administration to treat it. However, medications designed to treat the symptoms of Alzheimer's disease also appear to help people with vascular dementia.

Doctors may prescribe one or both types of the following drugs:

• Cholinesterase inhibitors — such as donepezil (Aricept), galantamine (Razadyne) and rivastigmine (Exelon) — are Alzheimer's drugs that work by boosting levels of a chemical messenger involved in memory and judgment. Side effects can include nausea, vomiting, muscle cramps and diarrhea.
• Memantine (Namenda) also has been shown to provide a modest benefit in people who have vascular dementia. Memantine works by regulating a chemical messenger involved in information processing, storage and retrieval. Side effects can include headache, constipation, confusion and dizziness.

Additionally, if you treat the risk factors that may have contributed to vascular dementia, you may be able to slow the progression of your dementia. That means controlling your blood pressure, cholesterol levels and diabetes, as well as quitting smoking. Doctors may also prescribe medications to help you control these conditions, along with aspirin or an anti-platelet aggregator medication, such as ticlopidine (Ticlid) and clopidogrel (Plavix), to help keep your arteries clear. None of these measures, however, can restore lost cognitive function.

Vascular dementia can be difficult for both the person with the disorder and his or her caregiver.

Familiar surroundings and a fairly predictable routine are helpful for people with vascular dementia. Some other things that might help include:

• Large calendars and clocks, because they help a person with dementia reorient themselves when they've forgotten the date or time.
• Let your loved one know what you're doing. For example, don't just lead him or her into the bathroom and start taking off his or her clothes. Let him or her know that it's time for a bath or shower.
• Provide some type of stimulus in his or her room, such as a TV or radio.
• Be sure your loved one has regular activities to participate in, such as going for a walk.

Taking care of someone with vascular dementia is a lot of work and can cause a lot of worry. Stress and burnout are common in caregivers. Ask your loved one's doctor what resources are available in your area and for your situation. Many people also find support groups helpful.

Changing the following modifiable risk factors may help you prevent vascular dementia:

• A healthy blood pressure. Keeping your blood pressure in the normal range can help prevent dementia in general. One study showed that the risk of Alzheimer's disease and vascular dementia was halved in people who controlled their high blood pressure with a calcium channel blocker. The use of a diuretic plus an ACE inhibitor may slightly reduce the risk of dementia.
• Normal cholesterol levels. Cholesterol-lowering medications can reduce your risk of vascular dementia, probably by reducing the amounts of deposits building up inside the brain's arteries.
• Prevent or control diabetes. Avoiding the onset of diabetes, with diet and exercise, is another possible way to decrease your risk of dementia. If you already have diabetes, controlling your glucose levels can reduce vascular damage and improve cognitive function.
• Quit smoking. Smoking tobacco contributes to poor vascular health, so quitting may help prevent vascular dementia.