Midline Brain Abnormalities Across Psychotic and Mood Disorders

Patients with schizophrenia are known to have increased prevalence of abnormalities in midline brain structures, such as a failure of the septum pellucidum to fuse (cavum septum pellucidum) and the absence of the adhesio interthalamica. This is the first study to investigate the prevalence of these abnormalities across a large multidiagnostic sample. Presence of cavum septum pellucidum and absence of the adhesio interthalamica was assessed in 639 patients with chronic schizophrenia, delusional disorder, schizoaffective disorder, bipolar disorder, major depressive disorder, or a first episode of psychosis, mania or unipolar depression. This was compared with 223 healthy controls using logistic-regression-derived odds ratios (OR). Patients with psychotic or mood disorders showed an increased prevalence of both abnormalities (OR of cavum septum pellucidum = 2.1, OR of absence of the adhesio interthalamica = 2.6, OR of both cavum septum pellucidum and absence of the adhesio interthalamica = 3.8, all P < .001). This increased prevalence was separately observed in nearly all disorders as well as after controlling for potential confounding factors. This study supports a general increased prevalence of midline brain abnormalities across mood and psychotic disorders. This nonspecificity may suggest that these disorders share a common neurodevelopmental etiology.