Empirical Evidence for Cognitive Subgroups in Body Dysmorphic Disorder [article]

Amy Malcolm, Sarah N Brennan, Sally A Grace, Toni D Pikoos, Wei Lin Toh, Izelle Labuschagne, Ben Buchanan, Ryan A Kaplan, David J Castle, Susan L Rossell
2020 medRxiv   pre-print
Objective: Current understanding of cognitive functioning in body dysmorphic disorder (BDD) is limited, owing to few studies, small sample sizes, and assessment across only limited cognitive domains. Existing research has also shown inconsistent findings, with both intact and impaired cognition reported in BDD, which might point toward cognitive heterogeneity in the disorder. This study aimed to examine the cognitive profile of BDD in a large sample across eight cognitive domains, and to
more » ... ains, and to explore whether cognitive subgroups might be identified within BDD. Methods: Cognitive domains of inhibition/flexibility, working memory, speed of processing, reasoning and problem-solving, visual and verbal learning, attention/vigilance and social cognition were assessed and compared between 65 BDD patients and 70 healthy controls. Then, hierarchical clustering analysis was conducted on the BDD group's cognitive data. Results: Group-average comparisons demonstrated significantly poorer cognitive functioning in BDD than healthy controls in all domains except for attention/vigilance and social cognition. Cluster analysis identified two divergent cognitive subgroups within our BDD cohort characterised by i) broadly intact cognitive function with mild selective impairments (72.3%), and ii) broadly impaired cognitive function (27.7%). However, the clusters did not significantly differ on clinical parameters or most sociodemographic characteristics. Conclusion: Cognitively diverse subgroups were identified within BDD, yet these were obscured in group-average comparisons. However, subgroup profiles of cognitive functioning seem unrelated to the clinical presentation of BDD. Further research into the underlying mechanisms of cognition in BDD is warranted.
doi:10.1101/2020.06.29.20143073 fatcat:dm7aid7whber7fopsp3lgglmhq