Cognitive impairment in bipolar II disorder

Abstract

Cognitive impairment exists in both subtypes of bipolar disorder, although more so in the bipolar I group. The best predictors of poor psychosocial functioning in bipolar II disorder were subclinical depressive symptoms, early onset of illness and poor performance on a measure related to executive function.

Are bipolar II patients cognitively impaired? A systematic review

“…Three studies using this test did not find impaired BD II patients (Summers et al 2006 ;Torrent et al 2006 ;Savitz et al 2008). However, Torrent et al (2006) found that BD II patients, as well as BD I patients, showed a trend towards a higher number of perseverative errors compared with HCs, which may also be related to greater impulsivity.…”

“…Three studies using this test did not find impaired BD II patients (Summers et al 2006 ;Torrent et al 2006 ;Savitz et al 2008). However, Torrent et al (2006) found that BD II patients, as well as BD I patients, showed a trend towards a higher number of perseverative errors compared with HCs, which may also be related to greater impulsivity. In two studies, cognitive flexibility was evaluated with another measure, the Intra-Dimensional/Extra-Dimensional Set-Shift subtest from CANTAB, with contradictory results ; one of them found that unmedicated BD II depressed subjects demonstrated intact performance (Taylor Tavares et al 2007) and the other found that BD II patients scored significantly lower than BD I patients (Summers et al 2006).…”

“…Regarding phonemic verbal fluency, five out of six studies did not find a deficit in BD II patients (Summers et al 2006 ;Torrent et al 2006 ;Andersson et al 2008 ;Savitz et al 2008 ;Simonsen et al 2008), while Harkavy-Friedman et al (2006) pointed out that BD II patients had a worse performance than HC subjects in this task. It is also important to underline that BD II subjects in the latter study were depressed, so this finding may be related to findings reported by Martínez-Arán et al (2002, 2004b where the only significant difference between euthymic patients and depressed patients was observed in verbal fluency, suggesting that performance in the phonemic fluency task may be state-dependent.…”

“…Three studies out of five did not find differences between the BD II and HC groups (Harkavy-Friedman et al 2006 ;Torrent et al 2006 ;Hsiao et al 2009). In the study by Summers et al (2006) BD II patients were not impaired with respect to the normative data on the TMT-B, although they scored significantly lower than BD I participants on this measure.…”

“…In studies with samples formed of euthymic patients or patients with mild or residual symptomatology, deficits in some working memory measures were detected (Summers et al 2006 ;Torrent et al 2006 ;Andersson et al 2008 ;Dittmann et al 2008 ;Simonsen et al 2008 ;Hsiao et al 2009). In this regard, Summers et al (2006) found that BD II patients were significantly more impaired than BD I patients.…”