Abstract
Negative symptoms (NS) of schizophrenia are persistent signs and symptoms with a significant impact on functioning of patients. They appear to be resistant to treatment and this makes them a significant unmet need in patients with schizophrenia.
During the last decade their detection and measurement arose renewed interest, that was also focused on their clinical significance and putative pathogenesis. New scales BNSS (Brief Negative Symptoms Scale) and CAINS (Clinical Assessment Interview for Negative Symptoms) were constructed and validated.
In addition to the division of negative symptoms into primary and secondary, the categories of "predominant" and "persistent" NS were introduced into psychopharmacological research. The structure of negative symptoms is represented by two domains "Motivation and Pleasure Factor" (avolition, social withdrawal, anhedonia) and the "Expressive Factor", related to the lack of verbal as well as nonverbal communication and emotional blunting.
There is no pathophysiology based treatment of NS. However, there are hypotheses that may serve as a background for adjunctive pharmacological treatment attempts.
Second generation antipsychotics, adjunctive antidepressants, glutamatergic transmission modulating compounds, hormones and anti-inflammatory agents have all been tested. Promising results were reported with the new antipsychotic cariprazine.
Meeting the challenge of negative symptoms may bring more effective treatment and better functioning to patients with schizophrenia. It also may help psychiatry to better understand the core psychopathology of schizophrenia.