Early versus late risk factors for deficit and nondeficit schizophrenia

Publication: Revista de Psiquiatría y Salud Mental

Alabaf S, Kirkpatrick B, Chen S, Cardinal RN, Fernández-Egea E

10 April 2021


Schizophrenia typically involves so-called “positive” or psychotic symptoms (symptoms that are present but are unwanted), but sometimes also so-called “negative” or deficit symptoms (aspects of normal behaviour that are absent).

In a group of 167 patients with schizophrenia and being treated with clozapine, those patients with “non-deficit” schizophrenia were more likely than those with “deficit” schizophrenia to have reported cannabis use by the time of their first-episode psychosis, or trauma (related to crime or abuse) prior to that first episode of psychosis.

Patients with “deficit” schizophrenia were more likely to have been born in summer months. The timing of stressors during brain development may influence the pattern of symptoms that emerge.

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