Mild Cognitive Impairment - Lewy Body (MCI-LB)

Until recently, a person had to be experiencing some sort of memory loss to be diagnosed with Mild Cognitive Impairment (MCI). However, in the last few years a new type of MCI has been identified—one that LBD families were quite familiar with. In MCI-LB, the basic definition remains the same: cognitive losses not severe enough to significantly interfere with functional ability or activities of daily living. However, the cognitive losses are “non-amnestic,” that is, they involve cognitive functions other than memory.

Dementia usually starts as mild cognitive impairment and increases very slowly. MCI-LB can occur by itself, or with other non-cognitive symptoms that also warn of eventual LBD.  Very little is known of how MCI precedes DLB, but much is being learned about how it occurs with PD. Here are some statistics:

• Mild cognitive impairment occurs in about 25% of newly diagnosed PD patient.
• The risk for dementia increases when MCI is present at or near PD diagnosis.
• The risk for dementia increases even more when other risk factors are also present at or near a PD diagnosis.

A person may have only one of the following symptoms (single domain) or several (multiple domain) or even all of them. However, to be defined as MCI, there must be some loss of executive function or memory. The John Hopkins Health Alerts listed these symptoms for non-amnestic MCI:

•    Executive function. These include difficulties with problem-solving, initiating and planning, multitasking, impulse control, following through and monitoring performance.

•    Memory. Memory retrieval may become difficult. This may include tasks learned long ago—playing the piano, using electrical equipment, driving or even brushing one’s teeth. Learning new information is still possible with adequate repetition.

•    Mental processing. Mental processes slow down the ability to process and respond to information. This has a domino effect that can impair other cognitive abilities, including problem-solving and memory retrieval.

•    Language. Finding the proper word to use becomes difficult (it’s on the tip of my tongue syndrome). 

•   Multitasking. Understanding and processing complex information becomes difficult. Being presented with more than one idea or choice at a time or needing to perform sequential tasks may become frustrating and stressful.

•    Attention. Maintaining focus or doing more than one thing at a time becomes difficult.

•    Visual-spatial abilities. Perceiving, processing and acting on visual information becomes difficult. This impairs driving, reaching or walking.

We are well aware that the most bothersome symptoms of MCI-LB are usually non-cognitive—things like hallucinations and even delusions. We plan to discuss them in a later blog.