Neurocognitive functioning in schizophrenia and bipolar disorder: Clarifying concepts of diagnostic dichotomy versus continuum
The Kraepelinian dichotomy posits that patients with schizophrenia (SCZ) and bipolar disorder (BD) present as two separate psychotic entities such that they differ in terms of clinical severity including neurocognitive functioning. Our study aimed to specifically compare and contrast the level of ne...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2013-12-01
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| Series: | Frontiers in Psychiatry |
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| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fpsyt.2013.00162/full |
| _version_ | 1818961135703949312 |
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| author | Carissa Nadia Kuswanto Min Yi eSum Kang eSim Kang eSim |
| author_facet | Carissa Nadia Kuswanto Min Yi eSum Kang eSim Kang eSim |
| author_sort | Carissa Nadia Kuswanto |
| collection | DOAJ |
| description | The Kraepelinian dichotomy posits that patients with schizophrenia (SCZ) and bipolar disorder (BD) present as two separate psychotic entities such that they differ in terms of clinical severity including neurocognitive functioning. Our study aimed to specifically compare and contrast the level of neurocognitive functioning between SCZ and BD patients and identify predictors of their poor neurocognitive functioning. We hypothesized that patients with SCZ had a similar level of neurcognitive impairment compared with BD. Forty-nine healthy controls (HC), 72 SCZ and 42 BD patients who were matched for age, gender, and premorbid IQ were administered the Brief Assessment of Cognition battery (BAC). Severity of psychopathology and socio-occupational functioning were assessed for both patients groups. Both BD and SCZ groups demonstrated similar patterns of neurocognitive deficits across several domains (verbal memory, working memory, semantic fluency, processing speed) compared with HC subjects. However, no significant difference was found in neurocognitive functioning between BD and SCZ patients, suggesting that both patient groups suffer the same degree of neurocognitive impairment. Patients with lower level of psychosocial functioning (F(1,112) = 2.661, p = 0.009) and older age (F(1,112) = -2.625, p = 0.010), not diagnosis or doses of psychotropic medications, predicted poorer overall neurocognitive functioning as measured by the lower BAC composite score. Our findings of comparable neurocognitive impairments between SCZ and BD affirm our hypothesis and support less the Kraepelinian concept of dichotomy but more of a continuum of psychotic spectrum conditions. This should urge clinicians to investigate further the underlying neural basis of these neurocognitive deficits, and be attentive to the associated socio-demographic and clinical profile in order to recognize and optimize early the management of the widespread neurocognitive deficits in patients with SCZ and BD. |
| first_indexed | 2024-12-20T12:08:37Z |
| format | Article |
| id | doaj.art-40efe69de0a84efaadc388db331536c0 |
| institution | Directory Open Access Journal |
| issn | 1664-0640 |
| language | English |
| last_indexed | 2024-12-20T12:08:37Z |
| publishDate | 2013-12-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Psychiatry |
| spelling | doaj.art-40efe69de0a84efaadc388db331536c02022-12-21T19:41:19ZengFrontiers Media S.A.Frontiers in Psychiatry1664-06402013-12-01410.3389/fpsyt.2013.0016264626Neurocognitive functioning in schizophrenia and bipolar disorder: Clarifying concepts of diagnostic dichotomy versus continuumCarissa Nadia Kuswanto0Min Yi eSum1Kang eSim2Kang eSim3Institute of Mental HealthInstitute of Mental HealthInstitute of Mental HealthInstitute of Mental HealthThe Kraepelinian dichotomy posits that patients with schizophrenia (SCZ) and bipolar disorder (BD) present as two separate psychotic entities such that they differ in terms of clinical severity including neurocognitive functioning. Our study aimed to specifically compare and contrast the level of neurocognitive functioning between SCZ and BD patients and identify predictors of their poor neurocognitive functioning. We hypothesized that patients with SCZ had a similar level of neurcognitive impairment compared with BD. Forty-nine healthy controls (HC), 72 SCZ and 42 BD patients who were matched for age, gender, and premorbid IQ were administered the Brief Assessment of Cognition battery (BAC). Severity of psychopathology and socio-occupational functioning were assessed for both patients groups. Both BD and SCZ groups demonstrated similar patterns of neurocognitive deficits across several domains (verbal memory, working memory, semantic fluency, processing speed) compared with HC subjects. However, no significant difference was found in neurocognitive functioning between BD and SCZ patients, suggesting that both patient groups suffer the same degree of neurocognitive impairment. Patients with lower level of psychosocial functioning (F(1,112) = 2.661, p = 0.009) and older age (F(1,112) = -2.625, p = 0.010), not diagnosis or doses of psychotropic medications, predicted poorer overall neurocognitive functioning as measured by the lower BAC composite score. Our findings of comparable neurocognitive impairments between SCZ and BD affirm our hypothesis and support less the Kraepelinian concept of dichotomy but more of a continuum of psychotic spectrum conditions. This should urge clinicians to investigate further the underlying neural basis of these neurocognitive deficits, and be attentive to the associated socio-demographic and clinical profile in order to recognize and optimize early the management of the widespread neurocognitive deficits in patients with SCZ and BD.http://journal.frontiersin.org/Journal/10.3389/fpsyt.2013.00162/fullSchizophreniabipolar disordersneurocognitive functionpsychosocial functioningKraepelinian dichotomypsychotic spectrum |
| spellingShingle | Carissa Nadia Kuswanto Min Yi eSum Kang eSim Kang eSim Neurocognitive functioning in schizophrenia and bipolar disorder: Clarifying concepts of diagnostic dichotomy versus continuum Frontiers in Psychiatry Schizophrenia bipolar disorders neurocognitive function psychosocial functioning Kraepelinian dichotomy psychotic spectrum |
| title | Neurocognitive functioning in schizophrenia and bipolar disorder: Clarifying concepts of diagnostic dichotomy versus continuum |
| title_full | Neurocognitive functioning in schizophrenia and bipolar disorder: Clarifying concepts of diagnostic dichotomy versus continuum |
| title_fullStr | Neurocognitive functioning in schizophrenia and bipolar disorder: Clarifying concepts of diagnostic dichotomy versus continuum |
| title_full_unstemmed | Neurocognitive functioning in schizophrenia and bipolar disorder: Clarifying concepts of diagnostic dichotomy versus continuum |
| title_short | Neurocognitive functioning in schizophrenia and bipolar disorder: Clarifying concepts of diagnostic dichotomy versus continuum |
| title_sort | neurocognitive functioning in schizophrenia and bipolar disorder clarifying concepts of diagnostic dichotomy versus continuum |
| topic | Schizophrenia bipolar disorders neurocognitive function psychosocial functioning Kraepelinian dichotomy psychotic spectrum |
| url | http://journal.frontiersin.org/Journal/10.3389/fpsyt.2013.00162/full |
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