Negative symptoms in individuals at clinical high risk of psychosis

• Type of Material: Article
• Authors: Danijela Piskulic, University of Calgary; Jean Addington, University of Calgary; Kristin S. Cadenhead, University of California at San Diego; Tyrone D. Cannon, University of California Los Angeles; Barbara A. Cornblatt, Zucker Hillside Hospital; Robert Heinssen, National Institutes of Health; Diana O. Perkins, University of North Carolina; Larry J. Seidman, Harvard Medical School; Ming T. Tsuang, University of California at San Diego; Elaine Walker, Emory University; Scott W. Woods, Yale University; Thomas H. McGlashan, Yale University
• Language: English
• Date: 2012-04
• Publisher: Elsevier: 12 months
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2012 Elsevier Ireland Ltd. All rights reserved.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.psychres.2012.02.018
• Title of Journal or Parent Work: Psychiatry Research
• ISSN: 0165-1781
• Volume: 196
• Issue: 2-3
• Start Page: 220
• End Page: 224
• Grant/Funding Information: This work was supported by the National Institute of Mental Health {grant numbers U01 MH066160 to SWW, U01 MH066134 to JA, R01 MH60720 and K24 MH76191 to KSC, R01 MH065079 to TDC, R01 MH061523 to BAC, R01 MH066069 and K23 MH01905to DOP, R18 MH 43518 (MTT and LJS), R01 MH065562 and P50 MH080272 to LJS, R21MH075027 to MTT, RO1MH062066 to EFW, K05MH01654 to THM]; Donaghue Foundation {to SWW]; and Eli Lilly & Co {to THM, JA, and DOP].
• Keywords: NAPLS1 project; psychosis prodrome; negative symptoms; conversion to psychosis; longitudinal study
• Research Categories: Psychology, Behavioral; Psychology, General

Abstract

Negative symptoms are present in the psychosis prodrome. However, the extent to which these symptoms are present prior to the onset of the first episode of psychosis remains under-researched. The goal of this study is to examine negative symptoms in a sample of individuals at clinical high risk (CHR) for psychosis and to determine if they are predictive of conversion to psychosis. Participants (n=138) were all participants in the North American Prodrome Longitudinal Study (NAPLS 1) project. Negative symptoms were assessed longitudinally using the Scale of Prodromal Symptoms. The mean total negative symptom score at baseline was 11.0, with 82.0% of the sample scoring at moderate severity or above on at least one negative symptom. Over the course of 12 months, the symptoms remained in the above moderate severity range for 54.0% of participants. Associations between individual symptoms were moderate (r= 0.31 to r= 0.57, P<0.001) and a factor analysis confirmed that all negative symptoms loaded heavily on one factor. Negative symptoms were more severe and persistent over-time in those who converted to psychosis, predicting the likelihood of conversion (χ2 = 17.63, df= 6, P< 0.01, R2 = 0.21). Thus, early and persistent negative symptoms may represent a vulnerability for risk of developing psychosis.