Dataset Information

The impact of premorbid and current intellect in schizophrenia: cognitive, symptom, and functional outcomes.

ABSTRACT:

Background

Cognitive heterogeneity among people with schizophrenia has been defined on the basis of premorbid and current intelligence quotient (IQ) estimates. In a relatively large, community cohort, we aimed to independently replicate and extend cognitive subtyping work by determining the extent of symptom severity and functional deficits in each group.

Methods

A total of 635 healthy controls and 534 patients with a diagnosis of schizophrenia or schizoaffective disorder were recruited through the Australian Schizophrenia Research Bank. Patients were classified into cognitive subgroups on the basis of the Wechsler Test of Adult Reading (a premorbid IQ estimate) and current overall cognitive abilities into preserved, deteriorated, and compromised groups using both clinical and empirical (k-means clustering) methods. Additional cognitive, functional, and symptom outcomes were compared among the resulting groups.

Results

A total of 157 patients (29%) classified as 'preserved' performed within one s.d. of control means in all cognitive domains. Patients classified as 'deteriorated' (n=239, 44%) performed more than one s.d. below control means in all cognitive domains except estimated premorbid IQ and current visuospatial abilities. A separate 138 patients (26%), classified as 'compromised,' performed more than one s.d. below control means in all cognitive domains and displayed greater impairment than other groups on symptom and functional measures.

Conclusions

In the present study, we independently replicated our previous cognitive classifications of people with schizophrenia. In addition, we extended previous work by demonstrating worse functional outcomes and symptom severity in the compromised group.

SUBMITTER: Wells R

PROVIDER: S-EPMC4849463 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Publications

The impact of premorbid and current intellect in schizophrenia: cognitive, symptom, and functional outcomes.

Wells Ruth R Swaminathan Vaidy V Sundram Suresh S Weinberg Danielle D Bruggemann Jason J Jacomb Isabella I Cropley Vanessa V Lenroot Rhoshel R Pereira Avril M AM Zalesky Andrew A Bousman Chad C Pantelis Christos C Weickert Cynthia Shannon CS Weickert Thomas W TW

NPJ schizophrenia 20151104

<h4>Background</h4>Cognitive heterogeneity among people with schizophrenia has been defined on the basis of premorbid and current intelligence quotient (IQ) estimates. In a relatively large, community cohort, we aimed to independently replicate and extend cognitive subtyping work by determining the extent of symptom severity and functional deficits in each group.<h4>Methods</h4>A total of 635 healthy controls and 534 patients with a diagnosis of schizophrenia or schizoaffective disorder were rec ...[more]

PMID: 27336046

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Dataset Information

The impact of premorbid and current intellect in schizophrenia: cognitive, symptom, and functional outcomes.

Background

Methods

Results

Conclusions

Publications

The impact of premorbid and current intellect in schizophrenia: cognitive, symptom, and functional outcomes.

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