Neuropsychological function reduced in BD II patients with comorbid anxiety
MedWire News: Comorbid anxiety disorder is associated with reduced neuropsychologic function in patients with bipolar II disorder (BD II), show results from a Taiwanese study.
Anxiety disorder is common in patients with BD, particularly those with BD II, observe Ru-Band Lu (National Cheng Kung University, Tainan) and colleagues.
However, they add that that little is known about the effect of comorbid anxiety disorder on neuropsychological function in BD II patients.
To address this, the team studied 40 interepisode BD II patients and 19 mentally healthy individuals. Of the BD II patients, 20 met DSM-IV criteria for anxiety disorder.
There were no significant differences between the three groups regarding age, gender, and education level. And there were no significant differences between the two BD II groups regarding age at onset, duration of illness, or scores on the Hamilton Depression Rating Scale and the Young Mania Rating Scale.
All of the participants underwent a battery of neuropsychologic function tests, including the Wechsler Memory Scale-third edition (WMS-III), the digit-symbol subtest of the Wechsler Adult Intelligence Scale-third edition (WAIS-III), and the Trail Making Test-Parts A and B (TMT-A, TMT-B, respectively).
The researchers found that BD II patients with comorbid anxiety disorder scored significantly worse than BD II patients without comorbid anxiety disorder and controls on the auditory immediate and auditory delayed subtests of the WMS-III, at 105.15 versus 116.37 and 119.68, and 108.90 versus 118.84 and 116.68, respectively.
BD II patients with comorbid anxiety disorder also had worse scores than the other two groups on the visual immediate and visual delayed subtests of the WMS-III, at 96.20 versus 113.74 and 110.68, and 98.05 versus 117.84 and 114.32, respectively.
In addition, BD II patients with comorbid anxiety disorder had poorer psychomotor speed on the TMT-A test and poorer working memory on the WMS-III test than the other two groups.
However, there were no significant differences among the three groups regarding scores for auditory recognition of delayed memory on the WMS-III test, attention on the WAIS-III test, and executive function on the TMT-B test.
Lu and team conclude in the journal Progress in Neuro-Psychopharmacology and Biological Psychiatry: "The current research provides the first empirical evidence confirming the negative effects of comorbid anxiety disorder in BD II patients during interepisode periods."
They add: "We suggest that clinical psychiatric practitioners should routinely conduct follow-ups on BD II patients in an attempt to assess whether they have comorbid anxiety disorder, and to design treatment modalities accordingly. The aim of treatment is not just to alleviate their mood symptoms, but also to diminish neuropsychological impairments, and to allow patients to regain their adaptive social functions."
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By Mark Cowen