Premorbid intelligence of inpatients with different psychiatric diagnoses does not differ

Paolo Stratta¹, Ilaria Riccardi², Annarita Tomassini², Maria Marronaro², Roberta Pacifico², Alessandro Rossi^2,3

¹Department of Mental Health, A.U.S.L. 4 L’Aquila, Italy; ²Department of Experimental Medicine, University of L’Aquila, Italy; ³Clinical Psychology Unit at Villa Serena, c/o ‘Casa di Cura Villa Serena’, Viale L. Petruzzi, 19, Città S.Angelo, Pescara, Italy

Abstract: The diagnostic specificity of poor premorbid intelligence is controversial. We explored premorbid intelligence level in psychiatric patients with personality disorders, depressive disorders, bipolar disorders and schizophrenic disorders. 273 consecutively admitted patients and 81 controls were included in the study and tested with the ‘Test di Intelligenza Breve’, an Italian adaptation of the National Adult Reading Test. Significant differences between the clinical samples and the control subjects were found but not among the 4 clinical groups. The observation of premorbid IQ deficits in subjects with diagnoses other than schizophrenia suggests a common vulnerability diathesis, which is most likely to have a neurodevelopmental basis.

Keywords: premorbid intelligence, psychiatric disorders, specificity