Dementia DSM-IV/ICD-10 or neurocognitive disorder DSM-5?

Background and Objectives: According to existing data the term dementia was invented in the first century BC. It was introduced in the European literature in the 17th and 18th centuries AC. At the end of the 17th century, the French Encyclopedia points at ethiological implications which would later shape legal concepts. In the 19th century the Centroeuropean research develops specific nosologies until, in the 20th century, senile dementia is gradually discredited. Methods: Slightly over ten years ago, the Mild Cognitive Disorder (MCD) conceptualization was introduced as an early stage of Alzheimer's disease (AD), but the lack of coherence in relation to lesions sparked a still ongoing controversy, as the author of the MCD concept belongs to the Writing Board of DSM 5. Results: The DSM IV focuses on a categorical approach in spite of the difficulty in differentiating "normal" from "pathological" impairment at certain ages. On the other hand, the DSM 5 adopts the Dimensional System with a Mild or Severe Neurocognitive Disorder definition, which is necessarily arbitrary and imposes a statistical criterion. The widespread use of this classification would imply diagnosing a large proportion of the population with huge social and medical implications. This triggered a variety of reactions, such as the APA note which claims that DSM 5 and CIE-10 "virtually contain the same codes". However a WHO study revealed that 70% of surveyed psychiatrists used CIE 10 criteria. Conclusions: The DSM 5 gives weight to cognitive aspects using as a severity criterion the number of standard deviations in relation to psychometric normality. It might be misleading if applied to some forms of dementia, for instance frontal dementias. The CIE-10 and DSM IV criteria are more operational.