The Greek conception of disease

In some respects, Galen is the founder of modern medical practice, not Hippocrates. This polymath Greek physician was one of the first to use scientific method in the understanding of disease. He thought that it was better, when searching for the truth, to prefer scientific assumptions and not consider the words of poets. In this regard, his seminal work linking personality to the Hippocratic four humours in his treatise, de Temperamentis ^{Reference Singer and van der Eijk1} is the start of a taxonomy of illness. He followed up on his patients and realised that a good diagnosis was one that predicted prognosis, ‘one of the essential problems and most important objectives of Galenic diagnosis’.^{Reference Mettern2}

Central to his conception of disease was the interplay between personality and the body. Too much yellow bile created the choleric temperament, too much black bile led to melancholia and too much phlegm created digestive problems. Only blood, linked to sanguine, pro-social and optimistic behaviour, was a positive humour. Critically, Galen recognised the need for balance of mind and body, in the humours, to ensure good health. Being a practising physician, Galen linked emotion to disease: ‘Anger and anxiety could cause or exacerbate epilepsy; along with diet, temperament, lifestyle, and environmental factors they could contribute to any number of feverish illnesses; anxiety in particular could trigger a sometimes fatal syndrome of insomnia, fever, and wasting, or transform into melancholy’.^{Reference Mettern2} The ideal temperament was characterised by a perfect symmetry in all physical and psychological characteristics.

Application of Galenic concepts to modern psychiatry

Despite this taxonomic model recognising the core links between body, mind and brain, much of Galen's theory has been lost in the modern biomedical taxonomic approach. This is particularly true in considering the division between personality disorder, however defined, and other mental illness. Galen considered that the four humours were not uniquely employed to describe character, but were strong determinants of illness and prognosis. Much of this is apparent to those working in the field and still occupies our minds.

Yet change has been slow. Recently, both the DSM-5 and ICD-11 classifications have recognised some of the critical problems with categorical personality disorders, and are now moving to a more dimensional approach in both classifications. This not only recognises the need for dimensions, but also that they change over time. Further, it recognises that imbalance can lead to functional impairment, or disease, as Galen would have seen it. This dimensional approach has moved beyond personality, although its use has yet to garner traction in day-to-day practice.

Examples of ‘Galenic syndromes’

There are, however, some elements of both personality and mental disorders that would appear to be Galenic disorders in their own right, rather than the two separate conditions of personality disorder and a combination of mental symptoms. Some of these are so closely linked that they should be regarded as consanguineous rather than comorbid conditions. It therefore appears pertinent to define these disorders as ‘Galenic syndromes’, which is defined as ‘a combination of personality disorder and clinical symptom complex so frequently associated that the two conditions should be considered as a single disorder’ (details available from the author on request).

There are three obvious contenders for Galenic syndromes. The first is the combination of the personality characteristic of neuroticism with the symptoms of common mental illness, mainly anxiety and depression. This has been called the general neurotic syndrome^{Reference Tyrer3} and is remarkably common, especially in primary and community healthcare, and in the general population.

The second can be called the Aristippean syndrome (after Aristippus of Cyrene, who believed that the purpose of life was the pursuit of pleasure). This joins up substance misuse in all its forms with the personality characteristics of disinhibition, recklessness and irresponsibility.^{Reference Newton-Howes and Foulds4}

The third is the Diogenes syndrome, sometimes wrongly applied to hoarding disorder quite inappropriately, as Diogenes lived a sparse existence. The true Diogenes syndrome combines one part of autism spectrum disorder, formerly called Asperger syndrome, with the personality profiles of detachment and anankastia (obsessive–compulsive features). These three syndromes have such strong personality characteristics that to ignore them in clinical practice is negligent.

What is the nature of the association?

If we accept that this close relationship between personality and mental state syndromes is true, the issue arises of how such a relationship ought to be construed. The following mechanisms have been proposed: pathogenic (i.e. A causes B), pathoplastic (A has an effect on the course and outcome of B), subsyndromal (A and B share a common underlying aetiology) and, finally, consequential (where A arises as a consequence of B). To complicate matters further, these relationships are also bi-directional (i.e. although A might cause B, B might also cause A), so that psychiatric syndromes may have an effect on personality as personality has an effect on psychiatric syndromes.

The jobbing clinician may well be bemused by this complexity, but it can be tested and also surmised in the clinical formulation – still a hallowed foundation of psychiatric training. A good formulation takes account of both the individual's history and circumstances, and an appropriate weighting to all sources of information, so that a coherent account of the presentation emerges. Although this must be idiographic, it is still the task of the assessing psychiatrist to construct hypotheses in the context of a formulation.

Concluding remarks

Taxonomy continues to develop in psychiatry, as the significant changes to the DSM-5 and ICD-11 make clear. Although there are understandable doubts about introducing new diagnostic constructions, the concept of Galenic syndromes will be helpful to psychiatrists who wish to acknowledge the presence of personality abnormality in their patients but are restrained by reluctance to use the words ‘personality disorder’. Modern models, such as the Hierarchical Taxonomy of Psychopathology (HiTOP),^{Reference Kotov, Krueger, Watson, Cicero, Conway and DeYoung5} are also attempting to do this; however, these remain complex, and in this taxonomic space, the concept of ‘Galenic syndromes’ provides the much needed broader link between personality pathology and psychopathology. We have offered three examples in this editorial and would encourage other groups to consider further possibilities in their areas of expertise.