Symptom domains of schizophrenia: the role of atypical antipsychotic agents.

Given their more obvious presentation, the reduction of positive symptoms and their associated behavioural problems have been considered the most important treatment outcome parameter in patients with schizophrenia. However, the development of the atypical antipsychotic agents in the early 1990s resulted in the adoption of more wide-reaching measures of therapeutic outcome. The aim of this review was to evaluate the efficacy of currently available atypical agents across multiple symptom domains of schizophrenia with a specific focus on negative symptoms, neurocognition, social functioning, quality of life and insight. As such, studies published between January 1990 and December 2005 that evaluated the clinical efficacy and tolerability of atypical antipsychotics in different symptom domains of schizophrenia were reviewed as identified from literature researches using MEDLINE and Embase. Abstracts and posters presented at key psychiatry and schizophrenia congresses during this period were also reviewed where available in the public domain. Results from the studies identified have consistently demonstrated that atypical antipsychotics have substantial advantages over conventional antipsychotics with a broader spectrum of efficacy across symptomatic domains of schizophrenia as proven by greater improvements in negative symptoms and cognitive function and a beneficial effect on affective symptoms and quality of life. However, their clinical advantages have often been limited by patients' partial compliance with therapy. As such, the development of a long-acting atypical antipsychotic agent may provide a new and valuable treatment option for patients with schizophrenia.