ABSTRACT
OBJECTIVE: An association between bipolar disorder and cognitive impairment has repeatedly been described, even for euthymic patients. Findings are inconsistent both across primary studies and previous meta-analyses. This study reanalysed 31 primary data sets as a single large sample (N = 2876) to provide a more definitive view. METHOD: Individual patient and control data were obtained from original authors for 11 measures from four common neuropsychological tests: California or Rey Verbal Learning Task (VLT), Trail Making Test (TMT), Digit Span and/or Wisconsin Card Sorting Task. RESULTS: Impairments were found for all 11 test-measures in the bipolar group after controlling for age, IQ and gender (Ps ≤ 0.001, E.S. = 0.26-0.63). Residual mood symptoms confound this result but cannot account for the effect sizes found. Impairments also seem unrelated to drug treatment. Some test-measures were weakly correlated with illness severity measures suggesting that some impairments may track illness progression. CONCLUSION: This reanalysis supports VLT, Digit Span and TMT as robust measures of cognitive impairments in bipolar disorder patients. The heterogeneity of some test results explains previous differences in meta-analyses. Better controlling for confounds suggests deficits may be smaller than previously reported but should be tracked longitudinally across illness progression and treatment.
Subject(s)
Affective Symptoms , Bipolar Disorder , Cognition Disorders , Mental Competency , Neuropsychological Tests , Psychotropic Drugs/adverse effects , Adult , Affect , Affective Symptoms/psychology , Age of Onset , Bipolar Disorder/complications , Bipolar Disorder/diagnosis , Bipolar Disorder/drug therapy , Bipolar Disorder/epidemiology , Cognition Disorders/diagnosis , Cognition Disorders/drug therapy , Cognition Disorders/epidemiology , Cognition Disorders/etiology , Confounding Factors, Epidemiologic , Female , Humans , Male , Mental Processes/drug effects , Middle Aged , Psychiatric Status Rating Scales , Psychotropic Drugs/administration & dosage , Risk FactorsABSTRACT
BACKGROUND: The psychological autopsy method offers the most direct technique currently available for examining the relationship between particular antecedents and suicide. This systematic review aimed to examine the results of studies of suicide that used a psychological autopsy method. METHOD: A computer aided search of MEDLINE, BIDS ISI and PSYCHLIT, supplemented by reports known to the reviewers and reports identified from the reference lists of other retrieved reports. Two investigators systematically and independently examined all reports. Median proportions were determined and population attributable fractions were calculated, where possible, in cases of suicide and controls. RESULTS: One hundred and fifty-four reports were identified, of which 76 met the criteria for inclusion; 54 were case series and 22 were case-control studies. The median proportion of cases with mental disorder was 91% (95 % CI 81-98%) in the case series. In the case-control studies the figure was 90% (88-95%) in the cases and 27% (14-48%) in the controls. Co-morbid mental disorder and substance abuse also preceded suicide in more cases (38%, 19-57%) than controls (6%, 0-13%). The population attributable fraction for mental disorder ranged from 47-74% in the seven studies in which it could be calculated. The effects of particular disorders and sociological variables have been insufficiently studied to draw clear conclusions. CONCLUSIONS: The results indicated that mental disorder was the most strongly associated variable of those that have been studied. Further studies should focus on specific disorders and psychosocial factors. Suicide prevention strategies may be most effective if focused on the treatment of mental disorders.
Subject(s)
Mental Disorders/epidemiology , Substance-Related Disorders/epidemiology , Suicide/psychology , Adolescent , Adult , Autopsy , Cluster Analysis , Comorbidity , Humans , Mental Disorders/prevention & control , Mental Disorders/psychology , Research Design , Substance-Related Disorders/psychology , Suicide PreventionABSTRACT
BACKGROUND: Neurocognitive impairments in euthymic patients with bipolar disorder may represent trait rather than state variables. AIMS: To test the hypothesis that euthymic patients with bipolar disorder would exhibit impairment in verbal learning and memory and executive function compared with healthy controls matched for age, gender and premorbid IQ. METHOD: Twenty euthymic patients with bipolar disorder were matched, on a case-by-case basis, to twenty healthy community controls. Cases and controls were tested with a battery of neuropsychological tests. RESULTS: Impairments were found in cases compared with controls in tests of verbal learning and memory. Verbal learning and memory correlated negatively with the number of manic episodes. CONCLUSIONS: Impaired verbal learning and memory may be a trait variable in bipolar disease. There are implications for adherence to medication and relapse and for the role of early treatment interventions. Prospective designs and targeting first-episode groups may help to differentiate trait v. disease process effects.
