What Are the Lewy Body Dementia Risk Factors Patients Should Know About?

Lewy body dementia, or dementia with Lewy bodies, is believed to be the third most common cause of dementia after Alzheimer’s disease and vascular dementia, accounting for approximately 5% to 10% of dementia cases. However, the pathology of Lewy body dementia and its risk factors are far less established and understood when compared to other causes of dementia, such as Alzheimer’s disease.

Below, we provide information on established and potential risk factors for Lewy body dementia and how to monitor the brain health of individuals at risk of developing Lewy body dementia.

What Is Lewy Body Dementia?

Lewy body dementia is a cause of progressive dementia that is clinically characterized by a decline in thinking, reasoning, and independent function. Symptoms include visual hallucinations, changes in cognitive abilities (thinking, reasoning, memory, and attention), changes in movement and gait, sleep disturbances, malfunctions of the autonomic nervous system, and depression. 

Neuropathological hallmarks, or key characteristics, of Lewy body dementia include the deposition of Lewy bodies and Lewy neurites. Lewy bodies, protein deposits made of abnormal filaments composed of alpha-synuclein, develop in nerve cells (neurons) within the regions of the brain responsible for memory, thinking, and motor control. Alpha-synuclein is found naturally in the brain; however, its function is not yet fully understood. Lewy neurites are abnormal neurites in diseased neurons and contain granular material and abnormal alpha-synuclein filaments similar to those in Lewy bodies.

Lewy Body Dementia Risk Factors

Although Lewy body dementia risk factors are less established and less understood than risk factors for other neurodegenerative diseases, several potential risk factors have been identified. Established and generally agreed-upon risk factors for Lewy body dementia include age, family history, and sex, described in more detail below.

• Age: Advanced age is the greatest known risk factor for Lewy body dementia. Lewy body dementia typically presents between the ages of 50 and 85, though it has been diagnosed in younger individuals.
• Family history: The hereditary nature of Lewy body dementia is not well established; however, experts believe that individuals with a family history of Lewy body dementia or Parkinson’s disease may be at greater risk.
• Sex: For many diseases, including those of the brain, sex plays a role in disease risk. Lewy body dementia is more prevalent in men than in women.

Conditions linked to vascular problems, such as hypertension, hyperlipidemia, and diabetes mellitus, as well as conditions that may result in social isolation and a lack of brain stimulation, like depression and loneliness, have been linked to many neurodegenerative and neurological diseases and conditions. Research suggests these conditions may also be risk factors for Lewy body dementia.

• Hypertension, diabetes mellitus, and hyperlipidemia: A 2018 population-based study found that hypertension, diabetes mellitus, and hyperlipidemia are both risk factors for Alzheimer’s disease and Lewy body dementia.
• Depression: A 2013 case-control study found that depression increases Lewy body dementia risk more strongly than it does in Alzheimer’s disease and Parkinson’s disease.

While there are no proven strategies for preventing Lewy body dementia, several aspects of healthy living may reduce the risk of developing dementia. In general, what is good for your heart is good for your brain. Experts recommend:

• Quitting smoking.
• Exercising daily (30-60 minutes/day).
• Eating a heart-healthy diet.
• Getting adequate sleep.
• Minimizing stress.
• Controlling alcohol consumption.

Monitoring Brain Health of At-Risk Patients

Monitoring the brain health of patients at risk of developing Lewy body dementia as early as possible is crucial to detect changes in function and enable early diagnosis, early intervention and treatment, and consequently, better health outcomes.

Additionally, individuals with modifiable Lewy body dementia risk factors, such as hypertension, diabetes, and depression, should closely monitor their brain health while modifying risk factors and making lifestyle changes.