Neurocognitive functioning in euthymic patients with bipolar disorder and unaffected relatives: A review of the literature

Abstract

Background Neurocognitive deficits are present in bipolar disorder (BD) patients and their unaffected (nonbipolar) relatives, but it is not clear which domains are most often impaired and the extent of the impairment resulting from shared genetic factors. In this literature review, we address these issues and identify specific neurocognitive tasks most sensitive to cognitive deficits in patients and unaffected relatives. Method We conducted a systematic review in Web of Science, PubMed/Medline and PsycINFO databases. Results Fifty-one articles assessing cognitive functioning in BD patients (23 studies) and unaffected relatives (28 studies) were examined. Patients and, less so, relatives show impairments in attention, processing speed, verbal learning/memory, and verbal fluency. Conclusion Studies were more likely to find impairment in patients than relatives, suggesting that some neurocognitive deficits may be a result of the illness itself and/or its treatment. However, small sample sizes, differences among relatives studied (e.g., relatedness, diagnostic status, age), and differences in assessment instruments may contribute to inconsistencies in reported neurocognitive performance among relatives. Additional studies addressing these issues are needed.

Neurocognitive performance as an endophenotype for mood disorder subgroups

“…The enhanced function in some of the domains in our sample differs from the deficits that characterize most earlier work on BPD (Bauer et al, 2016; Cardenas et al, 2016; Lee et al, 2014; Sharma et al, 2016), and may reflect findings from earlier studies that people with BPD may actually have superior functioning in some cognitive domains, and higher IQ, school performance, and social functioning prior to onset of BPD (Demjaha et al, 2012), even in childhood (Cannon et al, 2002; Koenen et al, 2009; MacCabe et al, 2010). Of particular relevance to our study, the line orientation task has been shown to index greater functional life skills performance (for basic financial tasks) (Allen et al, 2015), so our finding of greater accuracy in visuospatial function could actually have broader functional implications.…”

“…Associations found in these studies differ by source of the samples, mood disorder subgroups (Godard et al, 2011), clinical characteristics including current state (Martinez-Aran et al, 2004), medication use, psychotic features, severity, consequences (Jaeger et al, 2006; Martinez-Aran et al, 2007; Ruggero et al, 2007) or precursors of the disorder (Pavuluri et al, 2006), as well as substantial differences in the measures and domains assessed (Porter et al, 2015). To date, the most compelling evidence supports memory and attention as neurocognitive endophenotypes for BPD (Bora et al, 2009; Cardenas et al, 2016; Olvet et al, 2013). …”

Comparison of cognitive performance in bipolar disorder, major depressive disorder, unaffected first‐degree relatives, and healthy controls

“…A literature review of studies regarding the unaffected at‐risk relatives of BD patients found that these individuals had a higher rate of cognitive deficits in verbal memory and executive function than did the general population . A recent review again showed cognitive deficits in a population of relatives of BD patients compared with a healthy control (HC) group, but the affected domains differed from those of the patients . Accordingly, some functional magnetic resonance imaging studies demonstrated deficits in several brain regions and structural brain networks in non‐affected first‐degree relatives .…”

Transtorno afetivo bipolar e suas associações com traumas emocionais precoces, características psicossociais e reconhecimento de expressões faciais de emoção

“…Segundo o estudo, estes indivíduos apresentam prejuízos tanto na cognição geral quanto na cognição social, envolvendo especificamente os domínios de memória visual e verbal, velocidade de processamento, REFE e sustentação de atenção. Outros estudos pontuam que embora os parentes de indivíduos afetados pelo transtorno apresentem déficits neurocognitivos, não há um consenso acerca de quais domínios sofrem de tais prejuízos (BAUER et al, 2016;CARDENAS et al, 2016).…”