La mesure et l’évaluation de la conscience des troubles dans la schizophrénie connaissent un essor et un regain d’intérêt depuis une vingtaine d’années. La conscience d’avoir un trouble mental, que les auteurs anglosaxons traduisent par insight, doit être explorée comme un processus multidimensionnel et ne peut se limiter à une approche dichotomique en tout ou rien qui a longtemps dominé dans la pratique clinique. Les liens entre déficits de l’insight et mauvais pronostic dans le processus de soins sont l’explication première du nombre croissant de recherches dans ce domaine et leurs études représentent un intérêt majeur pour l’amélioration de la prise en charge des patients.

La schizophrénie est l’entité psychiatrique dans laquelle la conscience des troubles (ou insight) est la plus fréquemment altérée. Entre 50 et 80 % de la population de sujets affectés de schizophrénie présentent un déficit dans la conscience de leur maladie. Comparativement aux autres troubles mentaux (psychotiques ou non), la littérature internationale souligne depuis deux décennies l’importance et l’intensité des troubles de l’insight dans cette pathologie. Définie pendant très longtemps comme un phénomène dichotomique, la récente modélisation clinique de la conscience des troubles dans la psychose et le développement d’outils d’évaluation ont permis d’en souligner son aspect multifactoriel et dynamique. Dans cette revue de la question sur l’insight dans la schizophrénie, nous reviendrons sur l’évolution du concept d’insight en psychiatrie et sur sa définition. Les caractéristiques cliniques qui y sont spécifiquement associées seront abordées. L’ensemble des outils permettant d’évaluer l’insight dans la schizophrénie seront présentés et un intérêt particulier sera porté au modèle clinique d’Amador et à l’outil d’évaluation sur lequel il repose, la Scale to Assess Unawareness of Mental Disorder (SUMD). En conclusion les prises en charge des troubles de l’insight dans la schizophrénie seront évoquées.

Schizophrenia is the psychiatric disorder in which the awareness of pathology (or insight) is most frequently altered.

A review of the literature shows that between 50 and 80% of patients with schizophrenia do not believe they have a disorder. Studies published on this subject over the two last decades stressed the specificity of this phenomenon in schizophrenic patients, taking into account both its prevalence and its clinical consequences comparatively to other mental disorders. If in bipolar disorders a lack of insight is linked with the intensity and acuteness of symptomatology, there is only a limited relationship between these factors in schizophrenia, thus making lack of insight a trait rather than a state-related symptom.

Though defined for a very long time as a dichotomic phenomenon, the recent interest on insight in psychosis and the development of assessment tools for its evaluation have made it possible to underline its multifactorial and dynamic characteristics. Although lack of insight related to pathologies may vary across time in bipolar disorders, the results of clinical studies suggest that this phenomenon remains stable in schizophrenia.

In this review, we will reconsider the evolution of this concept in psychiatry and its definition. The clinical characteristics, which are specifically associated with the lack of insight in schizophrenia will be outlined. We will describe more specifically the model of Amador and Strauss and their assessment tool: the Scale to Assess Unawareness of Mental Disorder (SUMD). This model developed since the 1990s takes into account the time-related evolution of insight, and can be applied both to bipolar and psychotic disorders.

The SUMD has six general items and four subscales. The general items estimate the three most widely used definitions of insight: awareness of having a mental disorder, awareness of the achieved effects of medication and awareness of the social consequences of having a mental disorder, and include assessment of both current and past-time periods. Four other subscales, each composed of 17 items, assess awareness and attribution of specific current and retrospective symptoms as well as deficits associated with severe mental disorders. Insight, thus, appears as a multidimensional and continuous phenomenon, since patients’ awareness may apply only to part of their symptoms and vary over time. In this article, we will review existing scales assessing insight in schizophrenia. The deficiency of available scales validated in French limits the number of scientific publications concerning this important aspect of the clinical evaluation of schizophrenic patients.

Finally, interventions to improve insight in patients with schizophrenia are presented. Recent studies have shown cognitive behavioural therapy (CBT) to be of benefit in the treatment of poor insight in schizophrenia.

Evidence suggests that early diagnosis and treatment of schizophrenia leads to better prognosis. An important suggestion from theses studies may be that psychosocial therapy needs to focus on explanations that are in tune with the culture, rather than focus on diagnostic labels.