Hippocampal subfields in remitted schizophrenia

Current evidence of volume changes in hippocampal subdivisions in schizophrenia remains inconsistent, and few studies have investigated the relationship between regional hippocampal volumes and symptom remission.

In this cross-sectional study, we recruited 31 patients with schizophrenia and 31 healthy controls (HCs). Symptomatic remission in schizophrenia was determined according to Remission in Schizophrenia Working Group criteria. The volumes of hippocampal longitudinal subregions and transverse subfields were measured using manual and automatic techniques, respectively. Between-group regional hippocampal volume differences were analyzed using multivariate analysis of covariance followed by univariate analysis of covariance.

Compared with the HCs, the patients with schizophrenia had smaller bilateral heads and tails along the longitudinal axis; they also had reduced volumes of the bilateral CA1, CA3, CA4, GC-ML-DG, molecular layer, tail, left subiculum, left HATA, and right parasubiculum along the transverse axis in the hippocampus (all corrected p < 0.05). Furthermore, compared with the HCs and patients with remitted schizophrenia, the patients with nonremitted schizophrenia had smaller bilateral hippocampal tail subfields (corrected p < 0.05).

Our results indicated that the pathophysiology and symptomatic remission of schizophrenia are related to changes in the volumes of hippocampal subdivisions. These volume changes might be clinically relevant as biomarkers for schizophrenia identification and treatment.