Editor's choice

Neurodegenerative diseases raise profound questions

People increasingly understand that if they don't die of heart disease or cancer then brain failure is going to get them (p 1465). Neurological and psychiatric disorders account for only 1.4% of deaths but 28% of years lived with a disability (p 1469). As populations age the burden of illness caused by neurodegenerative illness will increase. That's one reason why we have devoted this issue to neurodegenerative disease (and our sister journal Journal of Neurology, Neurosurgery, and Psychiatry is doing the same with its June issue), but another is that it's a fascinating subject that raises fundamental questions.

Defining neurodegenerative diseases is difficult, but the "core members" are the dementias, Parkinson's disease, motor neurone disease, cerebellar degenerations, Huntington's disease, and prion disease (p 1465). But should more "psychiatric" diseases be included? Mary Baker, Rajendra Kale, and Mathew Menken, the editors of this issue, mount a powerful argument for ending the division between neurology and psychiatrya division that appeared only in the 20th century (p 1468). As our understanding of the brain grows, an increasing number of mental illnesses are shown to have a biological basisand more and more mental activities can be seen with increasingly sophisticated imaging (p 1529).

Science may bring together the ragbag of conditions called neurodegenerative diseases. Lawrence Golbe describes how all seem to be characterised by the aggregation of intracellular proteins caused by abnormalities in protein folding (p 1467). Understanding these abnormalities may bring new methods of treatment and prevention as well as a more rational classification of disease.

One of the questions raised by this issue is how doctors and patients can have very different perspectives. Mary Baker, a former chief executive of the Parkinson's Disease Association, observes tongue in cheek that for doctors Parkinson's disease is all above the waist while for patients its mostly below the waist. Doctors think about basal ganglia. Patients worry about continence, sexual function, and whether they can walk. An editorial she writes with Leslie Findley describes how doctors think that the condition of a patient with Parkinson's disease will be determined by severity of disease and adequacy of drug treatments (p 1466). In fact less than a fifth of variation of quality of life is accounted for by these two factors. Mood accounted for 40%, and the quality of communication with healthcare workers another large chunk.

But should the "unravelling of memory and mind" necessarily be regarded as a disease? Andrew Moscrop reviews a book that argues that dementia is emphatically human and brings a dramatic involvement in the present (p 1528). Defining it as a disease at the beginning of the 20th century reduced the condition to "a plain horror, an utterly inhuman circumstance."

Footnotes

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