Cognitive functioning in young people with first episode psychosis: relationship to diagnosis and clinical characteristics

Abstract

Objective: To examine the extent and nature of neuropsychological deficits in adolescents and young people with first episode psychosis (FEP), and to determine whether the pattern and extent of neuropsychological deficits varied according to diagnosis. Method: A total of 83 FEP subjects aged 13-25 years, and 31 healthy controls completed a comprehensive battery of neuropsychological tests, grouped into 10 cognitive domains. First episode psychosis subjects were stratified into three diagnostic groups (schizophrenia, affective disorders, substance-induced psychosis) and differences in cognitive profiles were examined. The contribution of demographic and clinical characteristics to cognitive performance was also explored. Results:The schizophrenia group demonstrated significantly worse performance on tasks of verbal learning and memory than the affective disorders group. Compared to healthy controls, the schizophrenia group also demonstrated global impairment across the majority of cognitive domains. The substance-induced group's performance lay between that of the schizophrenia and affective disorders groups. Analyses of differential deficits revealed that verbal learning, verbal memory and current intellectual functioning were selectively impaired in the schizophrenia group, whereas the affective disorders group demonstrated a selective deficit in speeded processing. Premorbid intellectual functioning, negative symptomatology and medication levels were the strongest predictors of cognitive performance in FEP subjects. Conclusions: Verbal memory deficits differentiate individuals with schizophrenia from those with psychotic affective disorders. Although significant cognitive deficits are evident across all diagnostic FEP groups, individuals with schizophrenia appear to have more generalized impairment across a broad array of cognitive functions than other psychotic diagnoses. Lower premorbid intellectual functioning does not appear to contribute to greater cognitive deterioration following onset of psychosis, but severity of illness may be a more important factor than levels of mood disturbance.

Cognitive course in first-episode psychosis and clinical correlates: A 4 year longitudinal study using the MATRICS Consensus Cognitive Battery

“…Whether or not cognitive performance differs significantly between subtypes of psychosis, such as affective and non-affective subtypes, has not been determined conclusively. Some evidence has suggested verbal learning performance to differ between individuals with schizophrenia from those with affective disorders (Fitzgerald et al, 2004) but this is not a consistent finding (Bora et al, 2009). Finally, longitudinal associations between cognitive deficits and quality of life outcome in schizophrenia have been supported by a review of 18 studies (Green et al, 2004), albeit with considerable variability (Tolman et al, 2010).…”

Neurocognitive Functioning in Bipolar Disorder: A Comprehensive Review of Recent Data

“…The speed of mental processing was reported to be slower in BD patients irrespective of illness phase and symptom severity (Antila et al 2009 ;Chaves et al 2011 ;Dittmann et al 2008a ;Hsiao et al 2009 ;Langenecker et al 2010 ;Martino et al 2011a ;Mur et al 2007 ;Basso et al 2009 ;Olley et al 2005 ;Xu et al 2012 ;McIntosh et al 2005 ;McGrath et al 1997 ;El-Badri et al 2001 ;Stoddart et al 2007 ;Coffman et al 1990 ;Seidman et al 2002 ;Fitzgerald et al 2004 ;Szoke et al 2008 ;Martinez-Aran et al 2008 ;Hill et al 2009 ;Dittmann et al 2008b ). It is less affected in comparison to patients with schizophrenia (Goldberg et al 1993 ;Hawkins et al 1997 ;Gard et al 1999 ;Mojtabai et al 2000 ) in spite of some data suggesting the presence of a similar degree of impairment (Hobart et al 1999 ).…”

“…The literature suggests that the attentional defi cit is widespread in BD; it covers all related processes. The magnitude of impairment is independent of the phase of the illness and current symptomatology although there is signifi cant variability present (Chaves et al 2011 ;Clark et al 2002Clark et al , 2005aFleck et al 2005 ;Liu et al 2002 ;Malhi et al 2007a ;Sanchez-Morla et al 2009 ;Elshahawi et al 2011 ;Strakowski et al 2004 ;Rund et al 1992 ;Thomas et al 1996 ;Harmer et al 2002a ;Zubieta et al 2001 ;Seidman et al 2002 ;Fitzgerald et al 2004 ;Glahn et al 2007 ;Hill et al 2009 ;Malloy-Diniz et al 2009 ;Wilder-Willis et al 2001 ;Ali et al 2000 ;Asarnow and MacCrimmon 1981 ). The defi cit is present already during the early stages of the disorder (Kolur et al 2006 ) and it is less pronounced in comparison to patients with schizophrenia (Goldberg et al 1993 ;Addington and Addington 1997 ;Park and Holzman 1992 ).…”

“…On the other hand, higher functioning and preserved neurocognitive performance during the premorbid phase, as well as higher social class, might push towards a mood disorder diagnosis rather than schizophrenia (Coryell et al 1989 ;Woodruff et al 1971 ;Morice 1990 ;Souza et al 1995 ;Seidman et al 2002 ;Goldberg et al 1993 ;Jones et al 1993 ;Gard et al 1999 ;Gilvarry et al 2000 ;Altshuler et al 2004 ;Silverstein et al 1990 ;Coffman et al 1990 ;Fitzgerald et al 2004 ;Dittmann et al 2008b ). Fortunately, today there are enough research data available to elucidate the true relationship between IQ and BD.…”

“…Fortunately, today there are enough research data available to elucidate the true relationship between IQ and BD. The literature consistently suggests that BD patients, irrespective of illness phase, show moderate global reduction in their neurocognitive functioning as refl ected in their IQ scores and their performance in a number of neuropsychological batteries (Donaldson et al 2003 ;Varga et al 2006 ;Coffman et al 1990 ;Fitzgerald et al 2004 ;Glahn et al 2007 ). Recent studies suggest that these defi cits are milder but maybe qualitatively similar to those of patients with schizophrenia (Schretlen et al 2007 ;Czobor et al 2007 ).…”