Cited by 83Bipolar Disorder and TreatmentSchizophrenia research and treatmentPersonality Disorders and Psychopathology

Evidence for cognitive subgroups in bipolar disorder and the influence of subclinical depression and sleep disturbances

Volkert, J., Kopf, J., Kazmaier, J., Glaser, F., Zierhut, K.C., Schiele, M.A., Kittel-Schneider, S., Reif, A.·2015·European Neuropsychopharmacology

Abstract

Recent research in bipolar disorder (BD) points to the relevance and persistence of cognitive deficits even in euthymia. Up to now, the mechanisms behind why some bipolar patients (BP) do not reach their former level of cognitive performance and psychosocial functioning while others remit completely, are not understood. In this study we aimed to identify a "cognitive deficit" vs. "non-deficit" subgroup within BD by using an extensive neuropsychological test battery. The test performance of 70 euthymic outpatients (BD-I and II, recruited as a sample of convenience from our bipolar disorder programme) was compared to 70 matched, healthy controls (HC). Furthermore, we investigated the association between demographic/clinical variables and the cognitive performance of BP. As expected, our sample of euthymic BP performed significantly worse than HC in psychomotor speed, divided attention, working memory, verbal memory, word fluency and problem solving. However, 41.4% of the patients did not have any neurocognitive deficits at all, and whether or not a patient belonged to the non-deficit group was not influenced by disease severity. Instead, our results demonstrate that patients suffering from persistent sleep disturbances and sub-threshold depressive symptomatology show more severe cognitive dysfunctions. In addition, antipsychotic treatment and comorbid anxiety disorder were associated with cognitive deficits. In sum, these results suggest that a major part of cognitive impairment is due to current symptomatology, especially sleep disorder and sub-syndromal depression. Rigorous treatment of these symptoms thus might well improve cognitive deficits and, as a consequence, overall functioning in BD.

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Crossref · 10.1016/j.euroneuro.2014.07.017

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Authors
Volkert, J., Kopf, J., Kazmaier, J., Glaser, F., Zierhut, K. C., Schiele, M. A., Kittel-Schneider, S., & Reif, A.
Affiliations
University of Würzburg (DE)
Corresponding author
Volkert, J.
Venue
European Neuropsychopharmacology
Publisher
Elsevier BV
Published
2015-02
Volume
25
Issue
2
Pages
192-202
ISSN
0924-977X (ISSN-L)
OpenAlex
W2048549939
Cited by
83
References
67
Citations by year
2026: 5 · 2025: 5 · 2024: 4 · 2023: 5 · 2022: 4 · 2021: 6 · 2020: 9 · 2019: 10 · 2018: 4 · 2017: 10 · 2016: 12 · 2015: 9
FWCI
7.88
Type
journal article
Language
en
Open access
closed
Locations
  • European Neuropsychopharmacology (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Psychiatry and Mental health › Bipolar Disorder and Treatment
  • Health Sciences › Medicine › Psychiatry and Mental health › Schizophrenia research and treatment
  • Social Sciences › Psychology › Clinical Psychology › Personality Disorders and Psychopathology
Keywords
bipolar disorder, cognitive impairment, euthymia, cognitive subgroups, sleep disorders, subthreshold depression, psychomotor speed, divided attention, working memory, verbal memory, verbal fluency, problem solving, antipsychotic drugs, anxiety comorbidity, disease severity
MeSH terms
Adult, Bipolar Disorder, Cognition, Cognition Disorders, Depression, Female, Humans, Male, Neuropsychological Tests, Outpatients, Psychiatric Status Rating Scales, Sleep Wake Disorders

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