Lack of insight in psychotic and affective disorders: a review of empirical studies.

In patients with psychotic or affective disorders, lack of insight is often a vexing clinical problem. However, it has infrequently been subjected to formal study. We have reviewed clinical psychiatric studies on insight in psychotic and affective disorders, selecting those that evaluated insight for each patient and presented the data in some quantitative fashion. Almost all studies focused on schizophrenia, with little research present on affective disorders. Definitions of insight varied among studies, as did diagnostic methods and other measures. Despite these limitations, several conclusions emerged. First, insight is not a unitary entity but has several dimensions, such as insight into symptoms and insight into need for treatment. Second, although insight may be poorer in patients with more-severe psychopathology, it does not always improve when psychopathological symptoms do. Third, insight is associated with medication compliance, prognosis, voluntary versus involuntary admission, and cultural concepts of disease. Fourth, insight into illness, need for treatment, or delusions may respond to cognitive and psychoeducational methods of treatment. To augment these findings, we suggest further avenues of research on insight.