Neurodegenerative Disease

Original Editor - Lucinda hampton

Top Contributors - Lucinda hampton and Kim Jackson  

Introduction[edit | edit source]

NDDs may affect mobility

Neurodegenerative diseases (NDD) are diverse conditions characterized by selective dysfunction and ongoing loss of neurons, glial cells and the neural networks in the brain and spinal cord. Accordingly they causes diverse problems examples being with movement (called ataxias), mental functioning (called dementias) and a person's ability to move, speak and breathe. NDD are incurable and debilitating conditions, and are becoming increasingly prevalent in part due to global population ageing[1][2] NDD impact many families - these disorders are not easy for the individual nor their loved ones.

They are diverse in their pathophysiology. Examples of NDD are:

Epidemiology[edit | edit source]

Man with dementia

In 2019, roughly 50 million people globally had a NDD, often resulting in dementia. This figure is predicted to rise to 152 million by 2060. These disorders are found among all age groups and in all geographical regions.

  • The overall prevalence of NDD leading to dementia in Europe is 1.6% and 1% for males and females respectively in the 65-69 age class, rising to 11% and 12.6% in the 85-89 age class.[4]
  • A WHO report sends a clear message: unless immediate action is taken globally, the neurological burden is expected to become an even more serious and unmanageable threat to public health"[5]

Etiology[edit | edit source]

Wheelchair provision

The majority of NDDs are due to a combination of genetic and environmental factors. This makes it difficult to predict who will develop disease. The greatest known risk factor for many NDDs is age.

  • Some NDDs are caused by inherited genetic changes. These disorders run in families: the faulty gene is transmitted from parents to their Huntington’s disease, and rare cases of motor neurone disease and Alzheimer’s disease.
  • Environmental factors also contribute to NDDs. eg. There is evidence linking Parkinson’s disease with long-term exposure to pesticides, toxins and chemicals.

Pathology[edit | edit source]

Amyloid plaque in AD

NDDs are characterized by progressive loss of selectively vulnerable populations of neurons, which contrasts with select static neuronal loss because of metabolic or toxic disorders. The most common neurodegenerative disorders are caused by protein abnormalities and include amyloidoses, tauopathies, and synucleinopathies. Note that often these protein abnormalities are present before the onset of clinical features.

NDDs can be classified according to:

  1. Primary clinical features, include: Alzheimer’s disease (AD); Dementia; Parkinson’s disease (PD) Parkinsonism, Motor Neurone Disease; Huntington’s disease (HD)
  2. Anatomic distribution of neurodegeneration, include: Frontotemporal dementia; Extrapyramidal disorders; Spinocerebellar ataxia; Spinal muscular atrophy (SMA)
  3. Principal molecular abnormality, include: Prion disease; Synucleinopathies. Amyloidoses,[3][1].

Earlier classifications focused on the clinical presentation, whereas as more and more NDDs are understood at a biochemical level, classifications have shifted towards the underlying pathological processes.[6]

Diagnosis[edit | edit source]

Ageing is a risk factor for NDD

NDDs are often presented as a distinct entity, however there is often overlap. None of the neurodegenerative disorders have perfect diagnostic accuracy. While pathological analysis is considered to be the gold standard in a wide spectrum of diseases, it cannot be applied to neurological processes. Studying disease heterogeneity at autopsy is key to understanding discrepancies between clinical and pathological diagnoses. This is a critical concept because there are many efforts to develop biomarkers to diagnose these diseases and to monitor disease progression in clinical trials[7][8]

Treatment[edit | edit source]

There are currently no drugs to prevent or cure NDDs. Treatment aims to control symptoms and includes:

  • Medications
  • Physiotherapy eg for gait training
  • Speech pathology eg for swallowing and speech training
  • Occupational therapy eg for home modifications
  • Psychiatry eg for depression.

Research is ongoing to find much-needed new treatments for neurodegenerative disorders[9]. A novel treatments uses stem cells to replace the neurons that have died.[10]

Physiotherapy[edit | edit source]

NDDs are a group of progressive neurological diseases that cause worsening motor, cognitive and autonomic dysfunction over time. Physiotherapy play a role in the management of these conditions and helping to improve quality of life for these individuals. Most patients are referred to physiotherapists treatment. See individual links for physiotherapy management.

References[edit | edit source]

  1. 1.0 1.1 1.2 Gitler AD, Dhillon P, Shorter J. Neurodegenerative disease: models, mechanisms, and a new hope.Available from; (last accessed 14.12.2020)
  2. Technology networks Pathophysiology of Neurodegenerative Diseases: New Approaches for Investigation and Recent Advances Available: (accessed 20.1.2023)
  3. 3.0 3.1 JPND research WHAT IS NEURODEGENERATIVE DISEASE? Available from; (last accessed 14.12.2020)
  4. Armstrong R. What causes neurodegenerative disease?. Folia Neuropathologica. 2020 Jan 1;58(2):93-112.Available:,20,41093,1,1.html (accessed 20.1.2023)
  5. WHO Chapter 4 Available from: (accessed 14.12.2020)
  6. Radiopedia Neurodegenerative disease Available: 21.1.2023)
  7. Gómez-Río M, Caballero MM, Gorriz Saez JM, Mínguez-Castellanos A. Diagnosis of neurodegenerative diseases: the clinical approach. Current Alzheimer research. 2016 May 1;13(5):469-74. Available: (accessed 21.1.20230
  8. Dugger BN, Dickson DW. Pathology of neurodegenerative diseases. Cold Spring Harbor perspectives in biology. 2017 Jul 1;9(7):a028035.Available from: (accessed 14.12.2020)
  9. WEHI Neurological Disorders Available from: (last accessed 14.12.2020)
  10. Frontiers What are Neurodegenerative Diseases and How Do They Affect the Brain? Available from: (accessed 14.12.2020)