title: Loneliness in psychotic disorders and its association with cognitive function and symptom profile.
abstract: BACKGROUND
  Loneliness involves subjective, rather than objective, social isolation and has a range of negative effects on mental and physical functioning. The purpose of this study was to examine the prevalence of loneliness in psychotic disorders and its association with symptoms and cognitive performance.
  
  
  METHODS
  Data were drawn from the second Australian National Survey of Psychosis and comprised responses from 1642 participants with an International Classification of Diseases 10 diagnosis of psychotic disorder who had completed a semi-structured interview of symptoms and social functioning (including loneliness), along with standardized assessments of current (digit symbol coding; DSC) and premorbid (National Adult Reading Test) cognitive ability. We examined the prevalence of loneliness across the diagnostic categories of psychosis, and its association with psychotic and non-psychotic symptoms and digit symbol coding scores.
  
  
  RESULTS
  The prevalence of loneliness was high, ranging from 74.75% in participants with delusional disorders to 93.8% in depressive psychosis, and was significantly higher than in the general population. Loneliness was also significantly associated with anhedonia and subjective thought disorder. Participants feeling socially isolated/lonely for company had significantly lower DSC scores than those who only felt lonely occasionally. Unexpectedly, participants who reported not feeling lonely had the lowest DSC scores.
  
  
  CONCLUSIONS
  Loneliness is common across all psychotic disorders, particularly in depressive psychosis. It is specifically associated with ongoing loss of pleasure and disordered thoughts as well as impairment in current cognitive functioning. However, poor cognitive functioning is not inevitably associated with loneliness. Implications for personalized treatment of psychosis are discussed.
authors.affiliation: Centre for Clinical Research in Neuropsychiatry, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Medical Research Foundation Building, Rear 50 Murray Street, Perth 6000, Australia; Cooperative Research Centre - Mental Health, Barry Street, Carlton, Victoria 3052, Australia. Electronic address: Johanna.badcock@uwa.edu.au.
authors.forename: Johanna C
authors.initials: JC
authors.lastname: Badcock
authors.affiliation: Neuropsychiatric Epidemiology Research Unit, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Medical Research Foundation Building, Rear 50 Murray Street, Perth 6000, Australia. Electronic address: Sonal.Shah@uwa.edu.au.
authors.forename: Sonal
authors.initials: S
authors.lastname: Shah
authors.affiliation: Orygen, The National Centre of Excellence in Youth Mental Health, University of Melbourne, Parkville, Victoria 3052, Australia. Electronic address: Andrew.Mackinnon@unimelb.edu.au.
authors.forename: Andrew
authors.initials: A
authors.lastname: Mackinnon
authors.affiliation: Mental Health Research Group, School of Medicine, Pharmacy and Health, Durham University, Stockton-On-Tees TS17 6BH, United Kingdom. Electronic address: helen.stain@durham.ac.uk.
authors.forename: Helen J
authors.initials: HJ
authors.lastname: Stain
authors.affiliation: School of Medicine, University of Adelaide, Ramsay Health Care (SA) Mental Health, Northern Adelaide Local Health Network, 33 Park Terrace, Gilberton, South Australia 5081, Australia; Ramsay Health Care (SA) Mental Health, Australia; Northern Adelaide Local Health Network, Australia. Electronic address: cherrie.galletly@adelaide.edu.au.
authors.forename: Cherrie
authors.initials: C
authors.lastname: Galletly
authors.affiliation: Centre for Clinical Research in Neuropsychiatry, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Medical Research Foundation Building, Rear 50 Murray Street, Perth 6000, Australia. Electronic address: Assen.Jablensky@uwa.edu.au.
authors.forename: Assen
authors.initials: A
authors.lastname: Jablensky
authors.affiliation: Centre for Clinical Research in Neuropsychiatry, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Medical Research Foundation Building, Rear 50 Murray Street, Perth 6000, Australia; Neuropsychiatric Epidemiology Research Unit, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Medical Research Foundation Building, Rear 50 Murray Street, Perth 6000, Australia. Electronic address: Vera.Morgan@uwa.edu.au.
authors.forename: Vera A
authors.initials: VA
authors.lastname: Morgan
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001317:Austria; D003072:Cognition Disorders / Q000209:etiology*; D005260:Female; D006801:Humans; D008132:Loneliness / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000150:complications / Q000453:epidemiology / Q000523:psychology; D012111:Residence Characteristics; D055815:Young Adult
keywords: Anhedonia; Cognition; Digit symbol coding; Psychosis; Social isolation