Understanding Rare Types of Dementia

Atypical Alzheimer’s Disease refers to unusual forms of Alzheimer’s that do not follow the typical progression of symptoms, starting with memory loss. It includes subtypes such as Frontal Variant Alzheimer’s Disease (fvAD) and Posterior Cortical Atrophy (PCA). Approximately 1 in 20 people with Alzheimer’s in the UK experience atypical forms, highlighting the need for specialised care and support.

Atypical Alzheimer’s is caused by brain changes similar to typical Alzheimer’s, but they begin in different brain regions. For fvAD, symptoms are related to behaviour and decision-making function, often affecting the frontal lobes first. This leads to changes in personality, social inhibition, and difficulties with complex tasks. PCA typically starts in the back of the brain, affecting visual processing, leading to challenges with recognising faces, judging distances, and spatial awareness.

While there’s no cure to halt the progression of atypical Alzheimer’s, treatments like donepezil and rivastigmine may improve symptoms. Management focuses on tailored support, including speech and occupational therapy, and adapting daily routines to the individual’s needs.

CBS is a condition causing movement disorders and cognitive decline, often misdiagnosed due to its similarity to other dementias.

CBS typically affects people between 60 and 80, with UK cases falling within this global statistic.

The causes of CBS are not fully understood. Symptoms range from stiff, jerky movements and difficulty speaking to cognitive challenges like memory loss and problems with visual perception.

There is no cure for CBS, but medications like donepezil and memantine can help manage cognitive symptoms, while physical therapies can aid movement.

Posterior Cortical Atrophy (PCA) is a rare form of dementia that primarily affects the back part of the brain responsible for processing visual information. It is characterised by a progressive, gradual decline in vision, such as difficulty recognising faces, objects, or difficulty reading. In the UK, PCA diagnosis typically occurs in individuals in their mid-50s to mid-60s.

PCA is often caused by Alzheimer’s disease-related changes in the brain but starts in the visual cortex. Early symptoms are subtle visual disturbances, which can lead to challenges with spatial awareness and complex visual tasks.

There is currently no cure for PCA, but some Alzheimer’s disease medications may offer slight improvements in cognitive symptoms. Visual aids and adaptations may also help manage the visual aspects of the condition.

Management of PCA involves creating a safe environment, utilising visual aids, and engaging in therapies that focus on enhancing remaining visual function and cognitive abilities.

Frontotemporal Dementia (FTD) is a group of disorders caused by progressive cell degeneration in the brain’s frontal or temporal lobes, affecting personality, behaviour, and language.

FTD is thought to account for less than 5% of all dementia cases in the UK. It typically affects individuals aged 45-64, representing a significant portion of younger-onset dementia cases.

FTD is often genetic, linked to mutations on several genes. Symptoms include changes in social behaviour, impulse control, and difficulties with language and movement.

There is no cure, but treatment focuses on managing behavioural symptoms with medications, including antidepressants and antipsychotics, and non-medication-based interventions like behavioural management strategies. This includes structured routines, developmental therapy, and caregiver support. Education on the condition and community resources are vital for families.

Normal Pressure Hydrocephalus (NPH) is an atypical type of dementia characterised by an accumulation of cerebrospinal fluid in the brain, leading to increased pressure and subsequent brain damage. This affects mobility, bladder control, and cognitive function.

NPH is underdiagnosed, often mistaken for more common conditions like Parkinson’s or Alzheimer’s. In the UK, awareness and recognition of NPH is gradually growing within the medical community.

NPH can occur without a known cause, or it can develop as a result of head injury, bleeding, or infection. Symptoms include difficulty walking, impaired bladder control, and cognitive challenges like apathy, poor attention, and memory loss.

Shunt surgery, which diverts fluid from the brain to the abdomen, can alleviate symptoms. Early intervention is critical for the best outcome. Post-surgery, physical therapy helps improve mobility, while cognitive and occupational therapies assist with daily living activities. Caregiver support and patient education are important for ongoing management.