Cognitive impairment in first-episode mania: a systematic review of the evidence in the acute and remission phases of the illness.
There is evidence of cognitive impairment that persists in the remission phase of bipolar disorder; however, the extent of the deficits that occur from the first onset of the disorder remains unclear. This is the first systematic review on cognitive functioning in the early stages of bipolar I disorder. The aim of the study was to identify the patterns and degree of cognitive impairment that exists from first-episode mania. Three electronic databases (MEDLINE, PsycINFO and PubMed) were systematically searched for studies published from January 1980 to June 2014. Eligible studies were separated into two groups: acute and remission. The Newcastle-Ottawa quality assessment scale was utilised to measure the quality of the included studies. A total of seven studies (three acute and four remission), including 230 first-episode mania and 345 healthy control participants, were eligible for the review. The studies in the acute phase only examined aspects of executive functioning, with impairments identified in cognitive flexibility, though not in response inhibition and verbal fluency relative to healthy controls. The most consistent finding during the remission phase was a deficit in working memory, whereas in the other domains, the findings were equivocal. Non-verbal memory and verbal fluency were not impacted in remission from first-episode mania. In conclusion, deficits are present in some but not all areas of cognitive functioning during the early stages of bipolar I disorder. Further research is warranted to understand the longitudinal trajectory of change from first-episode mania.
Orygen, The National Centre of Excellence in Youth Mental Health, 35 Poplar Road, Parkville, VIC 3052 Australia ; Centre for Youth Mental Health, The University of Melbourne, 35 Poplar Road, Parkville, VIC 3052 Australia.
Rothanthi
R
Daglas
Monash Clinical and Imaging Neuroscience (MCIN), School of Psychological Sciences and Monash Biomedical Imaging Facility, Monash University, 770 Blackburn Rd, Clayton, VIC 3168 Australia.
Murat
M
Yücel
Orygen, The National Centre of Excellence in Youth Mental Health, 35 Poplar Road, Parkville, VIC 3052 Australia ; Centre for Youth Mental Health, The University of Melbourne, 35 Poplar Road, Parkville, VIC 3052 Australia.
Sue
S
Cotton
Orygen, The National Centre of Excellence in Youth Mental Health, 35 Poplar Road, Parkville, VIC 3052 Australia ; Centre for Youth Mental Health, The University of Melbourne, 35 Poplar Road, Parkville, VIC 3052 Australia.
Kelly
K
Allott
Orygen, The National Centre of Excellence in Youth Mental Health, 35 Poplar Road, Parkville, VIC 3052 Australia ; Centre for Youth Mental Health, The University of Melbourne, 35 Poplar Road, Parkville, VIC 3052 Australia.
Sarah
S
Hetrick
Orygen, The National Centre of Excellence in Youth Mental Health, 35 Poplar Road, Parkville, VIC 3052 Australia ; Centre for Youth Mental Health, The University of Melbourne, 35 Poplar Road, Parkville, VIC 3052 Australia ; IMPACT Strategic Research Centre, School of Medicine, Deakin University, 288-299 Ryrie Street, PO Box 281, Geelong, VIC 3220 Australia ; Barwon Health and the Geelong Clinic, Swanston Centre, 288-299 Ryrie Street, P O Box 281, Geelong, VIC 3220 Australia ; Florey Institute for Neuroscience and Mental Health, Kenneth Myer Building, Royal Parade, Parkville, VIC 3220 Australia.
Michael
M
Berk
Bipolar disorder; Cognition; Depression; Early intervention; First episode; Mania