The concept of Deficit Schizophrenia (DS) is considered one of the most promising attempts to reduce heterogeneity within schizophrenia. Few prospective studies tested its longitudinal stability and ability to predict clinical features and outcome at five years follow-up.

In the present study 51 patients with DS and 43 with Nondeficit Schizophrenia (NDS), previously included in an Italian Multicenter Study on Deficit Schizophrenia, were reassessed after 5 years from the initial evaluation. The diagnosis of DS and NDS was made by raters blind to initial categorization using the Schedule for the Deficit Syndrome. Clinical, neurocognitive and social outcome indices were also evaluated.

The follow-up diagnosis confirmed the baseline one in forty-two out of 51 patients with DS (82.4%) and in 35 out of 54 with NDS (79.6%). Clinical, neuropsychological and social functioning characterization of patients with DS also revealed high reproducibility with respect to baseline assessment: anergia and negative dimension, social isolation and neurocognitive impairment (in particular general cognitive abilities and attention impairment) were more severe in patients with DS than in those with NDS. In neither group a significant deterioration of clinical, neurocognitive and social functioning indices was found, in line with previous studies in patients with chronic schizophrenia.

Study findings provide evidence for the long-term stability of Deficit Schizophrenia.