Psychiatric Diagnosis and Classification - ResearchGate

22 PSYCHIATRIC DIAGNOSIS AND CLASSIFICATION
molecular, imaging and computational tools have largely replaced traditional
clinical skills in making a diagnosis. In time, such developments
might result in a completely redesigned classification of mental disorders,
based on genetic aetiology [49]. The categories of such a classification and
their hierarchical ordering may disaggregate and recombine our present
clinical categories in quite unexpected ways, and eventually approximate
to a ``natural'' classification of psychiatric disorders.
This, indeed, is already happening in general medicine where molecular
biology and genetics are transforming medical classifications. New organizing
principles are producing new classes of disorders, and major chapters of
neurology are being rewritten to reflect novel taxonomic groupings such as
diseases due to nucleotide triplet repeat expansion or mitochondrial diseases
[50]. The potential of molecular genetic diagnosis in various medical disorders
is increasing steadily and is unlikely to bypass psychiatric disorders.
Although the majority of psychiatric disorders appear to be far more complex
from a genetic point of view than was assumed until recently, molecular
genetics and neuroscience will play an increasing role in the understanding
of their aetiology and pathogenesis. However, the extent of their impact on
the diagnostic process and the classification of psychiatric disorders is difficult
to predict. The eventual outcome is less likely to depend on the knowledge
base of psychiatry per se, than on the social, cultural and economic
forces that shape the public perception of mental illness and determine the
clinical practice of psychiatry. A possible but unlikely scenario is the advent
of an eliminativist ``mindless'' psychiatry which will be driven by biological
models and jettison psychopathology. It is much more likely in our view that
clinical psychiatry will retain psychopathology i.e. the systematic analysis
and description of subjective experience and behavior) at its core. It is also
likely that classification will evolve towards a system with at least two major
axes: one aetiological, using neurobiological and genetic organizing concepts,
and another syndromal or behavioral±dimensional. The mapping of
two such axes onto one another would provide a stimulating research
agenda for psychiatry for the foreseeable future.
REFERENCES
1. American Psychiatric Association 1980) Diagnostic and Statistical Manual of Mental
Disorders, 3rd edn DSM-III). American Psychiatric Association, Washington.
2. American Psychiatric Association 1987) Diagnostic and Statistical Manual of
Mental Disorders, 3rd edn, revised DSM-IIIR). American Psychiatric Association,
Washington.
3. World Health Organization 1992) The ICD-10 Classification of Mental and Behavioural
Disorders. Clinical Descriptions and Diagnostic Guidelines. World Health
Organization, Geneva.