Rarer Types of Dementia

Understanding the Rarer Types of Dementia

While Alzheimer's disease, vascular dementia, Lewy body dementia, and frontotemporal dementia are more widely recognised, there are several less common types of dementia that also impact people’s lives in complex and nuanced ways. Early diagnosis and person-centred care remain essential regardless of the type.

This manual is designed to provide an accessible overview of rarer dementias, equipping staff with key knowledge to better support clients living with these conditions.

1. Logopenic Progressive Aphasia (LPA)

Overview

LPA is one of the three forms of Primary Progressive Aphasia (PPA), a language-based dementia. While PPA is typically associated with frontotemporal dementia, LPA is most often caused by Alzheimer’s disease pathology, despite presenting differently.

Key Characteristics

• Word-finding difficulties (frequent pauses during speech)

• Impaired ability to repeat phrases or sentences

• Slowed or halting speech

• Relatively preserved grammar and motor speech

• Memory and reasoning may be unaffected in early stages

How to Support Someone with LPA

• Allow extra time for communication

• Use visual cues and gestures

• Avoid interrupting or finishing sentences

• Offer written alternatives (signs, cards, images)

• Maintain social engagement to reduce isolation

2. Posterior Cortical Atrophy (PCA)

Overview

PCA is a rare form of dementia that primarily affects the visual processing areas of the brain. It is often caused by Alzheimer’s disease but may also be linked to Lewy body dementia.

Key Characteristics

• Visual difficulties despite healthy eyes

• Problems judging distances or navigating spaces

• Difficulty recognising objects, faces, or reading

• Misinterpreting visual information (e.g. perceiving a flat floor as a step)

How to Support Someone with PCA

• Use high-contrast, clutter-free environments

• Avoid patterned flooring and backgrounds

• Label items clearly using colour coding

• Provide calm reassurance when navigating spaces

• Minimise glare and improve lighting

3. Corticobasal Syndrome (CBS)

Overview

CBS is a progressive neurological disorder that can cause both movement and cognitive problems. It may overlap with features of Alzheimer's or frontotemporal dementia.

Key Characteristics

• Stiffness or awkward movements in one limb

• Tremors, muscle jerks, or poor coordination

• Apraxia (inability to perform learned movements)

• Difficulty with speech and language

• Behavioural changes and cognitive decline

How to Support Someone with CBS

• Assist with physical tasks and mobility

• Use clear, simple instructions

• Encourage use of unaffected limbs

• Be patient with communication challenges

• Liaise with physiotherapy or occupational therapy if available

4. Huntington’s Disease Dementia

Overview

Huntington’s disease is an inherited disorder that leads to progressive degeneration of nerve cells. It typically appears between ages 30–50, affecting movement, mood, and thinking.

Key Characteristics

• Involuntary movements (chorea)

• Mood swings, irritability, or depression

• Memory and concentration difficulties

• Poor judgement and impulse control

• Progressive cognitive decline

How to Support Someone with Huntington’s

• Create a calm, low-stimulus environment

• Offer emotional support and reassurance

• Provide cues for memory and routine

• Encourage independence while offering help

• Coordinate with specialist clinics where needed

5. Limbic-Predominant Age-related TDP-43 Encephalopathy (LATE)

Overview

LATE is a newly recognised, age-related form of dementia that shares symptoms with Alzheimer’s but is biologically distinct. It is associated with abnormal deposits of the TDP-43 protein in the brain.

Key Characteristics

• Occurs typically in people aged 80+

• Slow memory loss that mimics Alzheimer’s

• Progressive difficulties with language and reasoning

• Less responsive to typical Alzheimer’s treatments

• Often co-exists with other brain pathologies

How to Support Someone with LATE

• Follow routines to reduce confusion

• Use familiar objects and places for orientation

• Offer reassurance during memory lapses

• Ensure continuity of companionship

• Monitor for signs of co-occurring conditions

6. Parkinson’s Disease Dementia (PDD)

Overview

This type of dementia can occur in people who have had Parkinson’s disease for a number of years. It shares similarities with Lewy body dementia.

Key Characteristics

• Slow thinking and memory problems

• Visual hallucinations

• Sleep disturbances

• Movement and balance issues

• Difficulty focusing or shifting attention

How to Support Someone with PDD

• Break tasks into small, manageable steps

• Use calm, reassuring language

• Encourage mobility and physical activity where safe

• Reduce distractions in the environment

• Offer structure and daily routines

7. Alcohol-Related Dementia / Korsakoff’s Syndrome

Overview

Caused by long-term alcohol misuse, particularly thiamine (vitamin B1) deficiency, this condition affects memory and behaviour.

Key Characteristics

• Severe short-term memory loss

• Confabulation (making up stories to fill memory gaps)

• Apathy or lack of insight

• Learning difficulties

How to Support Someone with Korsakoff’s

• Use repetition and visual reminders

• Maintain a consistent daily routine

• Avoid confrontation or correcting confabulated memories

• Support re-learning with encouragement

• Liaise with alcohol recovery services if relevant

Conclusion

These rarer types of dementia may be less familiar, but they deserve the same level of understanding, compassion, and personalised care. At Best Life Companions we have the ability to adapt to each individual’s experience of dementia and that is what makes the difference.

By learning more about each condition, we are better equipped to provide care that supports not just memory and function, but also dignity, connection, and joy.