Is suboptimal effort an issue? A systematic review on neuropsychological performance validity in major depressive disorder

Change in Cognitive Function over the Course of Major Depressive Disorder: A Systematic Review and Meta-analysis

Major depressive disorder (MDD) is associated with significant cognitive deficits during the acute and remitted stages. The aim of this systematic review and meta-analysis was to examine the course of cognitive function whilst considering demographic, treatment, or clinical features of MDD that could moderate the extent of cognitive change. Databases were searched to identify studies that reported on cognitive function in MDD with a ≥12-week test-retest interval. Relevant studies were pooled using random effects modelling to generate an inverse-variance, weighted, mean effect size estimate (Hedges' g) of cognitive change for each cognitive variable and for an overall composite cognitive domain. Of 6898 records, 99 eligible studies were identified from which 69 were meta-analysed, consisting of 4639 MDD patients (agemean = 40.25 years, female% = 64.62%) across 44 cognitive variables. In over 95% of cognitive variables, improvements were either of non-significant, negligible, or of a small magnitude, and when compared to matched healthy controls, the possibility of practice effects could not be precluded. Depressive symptom improvement and the number of previous depressive episodes moderated the extent of cognitive change, demonstrating state- and scar-like features for one-quarter of the cognitive domains. Further longitudinal studies are required to elucidate the MDD cognitive trajectory from initial onset. Findings nonetheless suggest that following pharmacological and non-pharmacological treatment, cognitive change in MDD is typically small, but the capacity for change may be less with episode recurrence. Targeting cognition early in the course of illness may facilitate better prognosis and support a more complete functional recovery.

Performance validity in a presurgical epilepsy population

Objective: This study examined the performance validity test (PVT) pass/fail rate in a sample of presurgical epilepsy candidates; assessed whether performance validity was associated with reduced performance across cognitive domains; investigated the relationship between performance validity and self-report mood questionnaires; and assessed whether PVT performance was associated with demographic or clinical factors (i.e. sex, race/ethnicity, age, years of education, reported history of special education, seizure longevity, and number of anti-seizure medications). Methods: One hundred and eighty-three presurgical epilepsy candidates were examined. Each patient's assessment battery included a stand-alone performance validity measure and two embedded validity measures. Results: PVT failure rate in this sample (10%) was associated with reduced performance on all neurocognitive measures: Full Scale IQ (FSIQ; r = -0.26), CVLT-II Total Learning (r = -0.36) and Long Delay Free Recall (LDFR; r = -0.38), BVMT-R Delayed Recall (r = -0.28), and Wisconsin Card Sorting Test (Categories Completed; r = -0.32). In addition, PVT failure rate was associated with elevated scores on the Beck Anxiety Inventory (r = .22) but not on the Beck Depression Inventory (BDI-II; r = .14). Correlations that were significant at the α = 0.05 level maintained significance following post hoc Bonferroni correction. The valid and invalid groups did not differ significantly in sex, race/ethnicity, age, years of education, reported history of special education, seizure longevity, and number of anti-seizure medications. Conclusions: Results from this study suggest that PVT performance was not impacted by demographic or clinical factors and therefore may be a reliable indicator of performance validity in a presurgical epilepsy sample.

Apathy and Depression Among People Aging With Traumatic Brain Injury: Relationships to Cognitive Performance and Psychosocial Functioning

OBJECTIVE

Apathy and depression are both common after moderate to severe traumatic brain injury (TBI) and may be especially important to distinguish in older adults with TBI. The authors examined apathy and depression in relation to cognitive performance domains and their potentially unique contribution to psychosocial functioning in this patient population.

METHODS

A total of 106 participants (mean±SD age=64±8 years) with chronic moderate to severe TBI (≥1 year) completed questionnaires assessing severity of apathy (Frontal Systems Behavior Scale-apathy subscale) and depression (Geriatric Depression Scale-15) symptoms, health-related quality of life (HRQoL), and societal participation. Participants also completed neuropsychological tests of episodic memory, processing speed, and executive functioning.

RESULTS

Apathy symptom severity was significantly associated with all cognitive performances in correlations adjusted for the familywise error rate; a relationship with executive functioning remained after controlling for demographic and injury variables. Depression symptom severity was not significantly associated with cognition after statistical correction. Both symptomatologies uniquely contributed to HRQoL. Only depression symptoms contributed to societal participation. On the basis of clinical cutoffs, half the sample had neither depression nor apathy, approximately 25% met criteria for only apathy, and 25% had both apathy and depression. The combined presence of clinical depression and apathy was associated with worse HRQoL and societal participation.

CONCLUSIONS

This is the first study to examine apathy and depression in relation to cognition and psychosocial functioning in an older sample with a history of TBI. Findings suggest that the two syndromes can be dissociated in clinically meaningful ways, which may help to refine psychiatric and behavioral interventions in this vulnerable population.