Defining neurodegenerative diseases

Disorders will be named after responsible rogue proteins and their solutions

Defining neurodegenerative diseases is like defining the continent of Europe: part history, part science, part politics, and to cap it, both could have an effect on health and prosperity.

A big advantage of the term is that it is a concept that patients can relate to from parallels in everyday life. Wearing out in time of certain components—sometimes replaceable, sometimes not—encompasses principles of selective neuronal death as a primary event with age as a major risk factor and good remedies patchy.

Paradoxes abound. Neurodegeneration is a major element and is often the cause of the disability in many diseases not usually classified as degenerative—for example, multiple sclerosis, epilepsy, some inborn errors of metabolism, schizophrenia, and even tumours. Conversely, inflammatory processes are activated and vascular compromise occurs in some degenerative diseases. A Napoleonic view could encompass most brain diseases under the rubric of neurodegenerative, but this would lack focus.

Few health authorities run services for neurodegenerative disease as a whole because they can cut across several subspecialties. Core members are the dementias, Parkinson's disease, motor neurone disease, cerebellar degenerations, Huntington's disease, and prion diseases. Subclassification is clearly of importance for …