ESPE Abstracts

Objective: Congenital Adrenal Hyperplasia (CAH) requires life-long replacement of cortisol. However, this long-term GC-treatment could change the developmental trajectory of the brain and predispose patients to problems with cognition and mood regulation. Previously, we have found impairments in working memory in patients with CAH, as well as alterations in brain structure in regions of the central executive network (CEN). These changes could be associated with differences in brain function during working memory. The present study therefore sought to compare working memory related brain activity between patients and healthy controls.

Methods: 29 patients with CAH (17 female) and 40 Controls (24 female), aged 16-33 years, underwent MRI 3T scanning while performing a verbal and visuo-spatial working memory task. Functional MRI images were analyzed with FSL FEAT to compare brain activity during the encoding and decoding phases of working memory between patients and healthy controls. In addition, interactions between group and sex on brain activity were assessed.

Results: On the whole group level, no differences in brain activity were found between patients and controls. However, there was an interaction with sex, during the decoding phase of visuo-spatial working memory. Males with CAH showed stronger activity in regions of the left parieto-occipital network, while females with CAH showed reduced activity in these areas. These regions are known to be involved in the processing of visuo-spatial information. However, activity changes were not associated with working memory performance or structure of regions of the CEN.

Conclusion: Overall, the brains of patients with CAH seemed to be able to compensate to healthy activity levels during working memory, despite thinner cortexes in the working memory network. However, hubs of the left dorsal-visual stream might be more sensitive for GC-disturbances in a sex-dependent manner. Future studies are needed to investigate sex-differences in brain activity in patients with CAH, and treatment optimization strategies to optimize brain function.