title: Randomized placebo-controlled adjunctive study of an extract of withania somnifera for cognitive dysfunction in bipolar disorder.
abstract: OBJECTIVE
  Cognitive impairments contribute significantly to inadequate functional recovery following illness episodes in bipolar disorder, yet data on treatment interventions are sparse. We assessed the cognitive effects of a standardized extract of the medicinal herb Withania somnifera (WSE) in bipolar disorder.
  
  
  METHODS
  Sixty euthymic subjects with DSM-IV bipolar disorder were enrolled in an 8-week, double-blind, placebo-controlled, randomized study of WSE (500 mg/d) as a procognitive agent added adjunctively to the medications being used as maintenance treatment for bipolar disorder. Study enrollment and data analyses were completed between December 2008 and September 2012. Cognitive testing at baseline and 8 weeks assessed primary efficacy outcomes. Psychopathology and adverse events were monitored at scheduled visits.
  
  
  RESULTS
  Fifty-three patients completed the study (WSE, n = 24; placebo, n = 29), and the 2 groups were matched in terms of demographic, illness, and treatment characteristics. Compared to placebo, WSE provided significant benefits for 3 cognitive tasks: digit span backward (P = .035), Flanker neutral response time (P = .033), and the social cognition response rating of the Penn Emotional Acuity Test (P = .045). The size of the WSE treatment effect for digit span backward was in the medium range (Cohen d = 0.51; 95% CI, 0.25-0.77). None of the other cognitive tasks showed significant between-group differences. Mood and anxiety scale scores remained stable, and adverse events were minor.
  
  
  CONCLUSIONS
  Although results are preliminary, WSE appears to improve auditory-verbal working memory (digit span backward), a measure of reaction time, and a measure of social cognition in bipolar disorder. Given the paucity of data for improving cognitive capacity in bipolar disorder, WSE offers promise, appears to have a benign side-effects profile, and merits further study.
  
  
  BACKGROUND
  ClinicalTrials.gov identifier: NCT00761761.
authors: Comprehensive Recovery Services, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, 3811 O'Hara St, Pittsburgh, PA chengappakn@upmc.edu.
authors: K N Roy
authors: KN
authors: Chengappa
authors: Christopher R
authors: CR
authors: Bowie
authors: Patricia J
authors: PJ
authors: Schlicht
authors: David
authors: D
authors: Fleet
authors: Jaspreet S
authors: JS
authors: Brar
authors: Ripu
authors: R
authors: Jindal
mesh_terms: D000328:Adult; D018692:Antimanic Agents / Q000627:therapeutic use; D001288:Attention / Q000187:drug effects; D001714:Bipolar Disorder / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D003072:Cognition Disorders / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D015507:Drugs, Investigational / Q000009:adverse effects / Q000627:therapeutic use*; D056344:Executive Function / Q000187:drug effects; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D008517:Phytotherapy; D010936:Plant Extracts / Q000009:adverse effects / Q000627:therapeutic use*; D011594:Psychometrics; D011930:Reaction Time / Q000187:drug effects; D032341:Withania
chemical_list: D018692:Antimanic Agents; D015507:Drugs, Investigational; D010936:Plant Extracts