ORIGINAL ARTICLE The relationship between predisposing factors, premorbid function and symptom dimensions in psychosis: an integrated approach AlmudenaGuerra 1 ,PaulFearon 2 *,PakSham 2 ,PeterJones 3 ,ShonLewis 4 , IgnacioMata 5 ,RobinMurray 2 1 Gerencia Torribera, Santa Coloma de Gramenet, Barcelona, Spain; 2 Institute of Psychiatry, London, UK; 3 Department of Psychiatry, University of Cambridge, UK; 4 MRCPsych, Academic Department of Psychiatry, Withington Hospital, Manchester, UK; 5 Hospital Virgen del Camino, Pamplona, Spain (Received 30 July 2001; accepted 22 May 2002) Summary – Background. Increasingevidencesuggestspsychosismaybemoremeaningfullyviewedindimensional termsratherthanasdiscretecategoricalstatesandthatspecificsymptomclustersmaybeidentified.Ifso,particular riskfactorsandpremorbidfactorsmaypredictthesesymptomclusters. Aims. (i)Toexplore,usingprincipalcomponent analysis,whetherspecificfactorsforpsychoticsymptomscanbeisolated.(ii)Toestablishthepredictorsofthedifferent symptomfactorsusingmultipleregressiontechniques. Method. Onehundredandeighty-nineinpatientswithpsychotic illnesswererecruitedandinformationonfamilyhistory,premorbidfactorsandcurrentsymptomsobtainedfromthem andtheirmothers. Results. Sevendistinctsymptomcomponentswereidentified.Regressionanalysisfailedtoidentify any developmental predictors of depression or mania. Delusions/hallucinations were predicted by a family history of schizophreniaandbypoorschoolfunctioninginspiteofnormalpremorbidIQ(F =6.5; P < 0.001);negativesymptoms by early onset of illness, developmental delay and a family history of psychosis (F =4.1; P = 0.04). Interestingly disorganisationwaspredictedbythecombinationoffamilyhistoryofbipolardisorderandlowpremorbidIQ(F =4.9; P = 0.003), and paranoia by obstetric complications (OCs) and poor school functioning (F =4.2; P =0.01). Conclusion. Delusions and hallucinations, negative symptoms and paranoia all appeared to have a developmental originthoughtheywereassociatedwithdifferentchildhoodproblems.Ontheotherhand,neithermanianordepression wasassociatedwithchildhooddysfunction.Ourmoststrikingfindingwasthatdisorganisationappearedtoarisewhen afamilialpredispositiontomaniawascompoundedbylowpremorbidIQ. © 2002Éditionsscientifiquesetmédicales ElsevierSAS Dimension / Factor / Integrated / Premorbid / Psychosis / Symptom INTRODUCTION Several lines of evidence suggest that neuro- developmental impairment increases the risk of later schizophrenia. The neuro-developmental hypothesis postulates that genetic and environmental factors oper- ate in fetal or neonatal life to cause abnormalities in brain development which are manifest in childhood *Corresponding author. E-mail address: p.fearon@iop.kcl.ac.uk (P. Fearon). Eur Psychiatry 2002; 17: 311-20 © 2002 Éditions scientifiques et médicales Elsevier SAS. All rights reserved S0924933802006855/FLA