Unravelling the impact of frontal lobe impairment for social dysfunction in myotonic dystrophy type 1.

Myotonic dystrophy type 1 is an autosomal dominant multisystemic disorder affecting muscular and extra muscular systems, including the central nervous system. Cerebral involvement in myotonic dystrophy type 1 is associated with subtle cognitive and behavioural disorders, of major impact on socio-professional adaptation. The social dysfunction and its potential relation to frontal lobe neuropsychology remain under-evaluated in this pathology. The neuroanatomical network underpinning that disorder is yet to disentangle. Twenty-eight myotonic dystrophy type 1 adult patients (mean age: 46 years old) and 18 age and sex-matched healthy controls were included in the study. All patients performed an exhaustive neuropsychological assessment with a specific focus on frontal lobe neuropsychology (motivation, social cognition and executive functions). Among them, 18 myotonic dystrophy type 1 patients and 18 healthy controls had a brain MRI with T1 and T2 Flair sequences. Grey matter segmentation, Voxel-based morphometry and cortical thickness estimation were performed with Statistical Parametric Mapping Software SPM12 and Freesurfer software. Furthermore, T2 white matter lesions and subcortical structures were segmented with Automated Volumetry Software. Most patients showed significant impairment in executive frontal functions (auditory working memory, inhibition, contextualization and mental flexibility). Patients showed only minor difficulties in social cognition tests mostly in cognitive Theory of Mind, but with relative sparing of affective Theory of Mind and emotion recognition. Neuroimaging analysis revealed atrophy mostly in the parahippocampal and hippocampal regions and to a lesser extent in basal ganglia, regions involved in social navigation and mental flexibility, respectively. Social cognition scores were correlated with right parahippocampal gyrus atrophy. Social dysfunction in myotonic dystrophy type 1 might be a consequence of cognitive impairment regarding mental flexibility and social contextualization rather than a specific social cognition deficit such as emotion recognition. We suggest that both white matter lesions and grey matter disease could account for this social dysfunction, involving, in particular, the frontal-subcortical network and the hippocampal/arahippocampal regions, brain regions known, respectively, to integrate contextualization and social navigation.

Psychosocial Impact of Predictive Genetic Testing in Hereditary Heart Diseases: The PREDICT Study.

Predictive genetic testing (PGT) is offered to asymptomatic relatives at risk of hereditary heart disease, but the impact of result disclosure has been little studied. We evaluated the psychosocial impacts of PGT in hereditary heart disease, using self-report questionnaires (including the State-Trait Anxiety Inventory) in 517 adults, administered three times to the prospective cohort (PCo: n = 264) and once to the retrospective cohort (RCo: n = 253). The main motivations for undergoing PGT were "to remove doubt" and "for their children". The level of anxiety increased between pre-test and result appointments (p <0.0001), returned to baseline after the result (PCo), and was moderately elevated at 4.4 years (RCo). Subjects with a history of depression or with high baseline anxiety were more likely to develop anxiety after PGT result (p = 0.004 and p <0.0001, respectively), whatever it was. Unfavourable changes in professional and/or family life were observed in 12.4% (PCo) and 18.7% (RCo) of subjects. Few regrets about PGT were expressed (0.8% RCo, 2.3% PCo). Medical benefit was not the main motivation, which emphasises the role of pre/post-test counselling. When PGT was performed by expert teams, the negative impact was modest, but careful management is required in specific categories of subjects, whatever the genetic test result.

Cognitive profile of patients with glycogen storage disease type III: a clinical description of seven cases.

BACKGROUND: Glycogen storage disease type III (GSDIII) is a rare autosomal recessive disorder due to glycogen debranching enzyme (GDE) deficiency. It results in a multisystemic disease with predominant hepatic and myopathic symptoms. While frequent social maladjustment has been observed in our clinical practice, cognitive and psychological disturbances have never been assessed. The aim of this pilot study was to examine and characterize the cognitive profile of patients with GSDIII. METHODS: Seven patients (six women and one man, mean age: 38.7 ± 11.6 years) with GSDIII underwent a neuropsychological set of tests assessing global cognitive efficiency, executive functions, social cognition, apathy, and episodic memory. RESULTS: All patients presented previous psychopathological history. We observed attention fluctuations for each patient, and impaired global cognitive efficiency with deficiencies in executive functions in 5/7 patients. Emotional skills (social cognition) were impaired in five patients. Memory was mostly preserved. CONCLUSION: The impairment in social cognition (recognition of emotions and ability to attribute mental states to others) and executive functions observed could be a consequence of orbito-frontal dysfunction due to the abnormal glycogen metabolism characteristic of the underlying disease. These results are consistent with the hypothesis of a central nervous system involvement in patients with GSDIII, but need to be confirmed in future research. This could explain the social and economic difficulties, and the lack of compliance to the medical follow-up presented by these patients. It suggests that these disturbances need to be taken into account when planning the medical management of patients with GSDIII.