Diagnostic issues in chronic schizophrenia: kraepelinian schizophrenia, undifferentiated schizophrenia, and state-independent negative symptoms

Data are presented concerning three recent clinical distinctions in schizophrenia: kraepelinian versus non-kraepelinian patients; mixed versus simple undifferentiated subtypes; and state-dependent versus state-independent negative symptoms. Schizophrenic patients who have been ill and dependent on others for the past 5 years ('kraepelinians') were compared to other chronic schizophrenics. The kraepelinian patients met the criteria for schizophrenia by more diagnostic systems than other patients, were less responsive to haloperidol, had more severe negative symptoms and formal thought disorder, and had similarly severe positive symptoms. They also had cerebral ventricles that demonstrated more left-to-right asymmetry and a greater family history of schizophrenia spectrum disorders. Mixed undifferentiated schizophrenic patients, who met criteria for more than one schizophrenic subtype, were compared to simple undifferentiated schizophrenic patients, who met criteria for no subtype. The mixed group was characterized by more severe positive and negative symptoms and formal thought disorder, worse social functioning, and a worse response to haloperidol. In a subgroup of patients who were studied once while in a state of exacerbation and once while in a state of relative remission, the negative symptoms of inattention and affective flattening were state-dependent, while anhedonia-asociality was state-independent.