Lewy body dementia (LBD) is a disease associated with abnormal deposits of a protein called alpha-syncline in the brain. These deposits, called Lewy bodies, affect chemicals in the brain whose changes, in turn, can lead to problems with thinking, movement, behavior, and mood. Lewy body dementia is one of the most common causes of dementia.
Diagnosing LBD can be challenging. Early LBD symptoms are often confused with similar symptoms found in other brain diseases or in psychiatric disorders. Lewy body dementia can occur alone or along with other brain disorders.
In the early stages of LBD, symptoms can be mild, and people can function fairly normally. As the disease advances, people with LBD require more help due to a decline in thinking and movement abilities. In the later stages of the disease, they often depend entirely on others for assistance and care.
The precise cause of LBD is unknown, but scientists are learning more about its biology and genetics. For example, we know that an accumulation of Lewy bodies is associated with a loss of certain neurons in the brain that produce two important chemicals that act as messengers between brain cells (called neurotransmitters). One of these messengers, oxyacetylene, is important for memory and learning. The other, dopamine, plays an important role in behavior, cognition, movement, motivation, sleep, and mood.
Cognitive Symptoms of LBD:
LBD causes changes in thinking abilities. These changes may include:
– Visual hallucinations, or seeing things that are not present. Visual hallucinations occur in up to 80 percent of people with LBD, often early on. Non visual hallucinations, such as hearing or smelling things that are not present, are less common than visual ones but may also occur.
– Unpredictable changes in concentration, attention, alertness, and wakefulness from day to day and sometimes throughout the day. Ideas may be disorganized, unclear, or illogical. These kinds of changes are common in LBD and may help distinguish it from Alzheimer’s disease.
– Severe loss of thinking abilities that interfere with daily activities. Unlike in Alzheimer’s dementia, memory problems may not be evident at first but often arise as LBD progresses. Other changes related to thinking may include poor judgment, confusion about time and place, and difficulty with language and numbers.
Movement problems and Lewy body dementia:
Some people with LBD may not experience significant movement problems for several years. Others may have them early on. At first, movement symptoms, such as a change in handwriting, may be very mild and easily overlooked. Movement problems may include:
– Muscle rigidity or stiffness
– Shuffling walk, slow movement, or frozen stance
– Tremor or shaking, most commonly at rest
– Balance problems and repeated falls
– Stooped posture
– Loss of coordination
– Smaller handwriting than was usual for the person
– Reduced facial expression
– Difficulty swallowing
– A weak voice
Lewy body dementia and sleep:
Sleep disorders are common in people with LBD, but are often undiagnosed. A sleep specialist can help diagnose and treat sleep disorders.
Sleep-related disorders seen in people with LBD may include:
– REM sleep behaviour disorder
– Excessive daytime sleepiness (sleeping two or more hours during the day)
– Insomnia
– Restless leg syndrome
Behavioral and mood symptoms of Lewy body dementia:
Changes in behavior and mood are possible in LBD and may worsen as the person’s thinking abilities decline. These changes may include:
– Depression
– Apathy, or a lack of interest in normal daily activities or events and less social interaction
– Anxiety and related behaviors, such as asking the same questions over and over or being angry or fearful when a loved one is not present
– Agitation, or restlessness, and related behaviors, such as pacing, hand wringing, an inability to get settled, constant repeating of words or phrases, or irritability
– Delusions, or strongly held false beliefs or opinions not based on evidence. For example, a person may think his or her spouse is having an affair or that relatives long dead are still living.
– Paranoia, or an extreme, irrational distrust of others, such as suspicion that people are taking or hiding things
Other Symptoms:
People with LBD can also experience significant changes in the part of the nervous system that regulates automatic functions such as those of the heart, glands, and muscles. The person may have:
– Changes in body temperature
– Problems with blood pressure
– Dizziness
– Fainting
– Frequent falls
– Sensitivity to heat and cold
– Sexual dysfunction
– Urinary incontinence
– Constipation
– A poor sense of smell
