Dysautonomia and functional impairment in rare developmental and epileptic encephalopathies: the other nervous system.

Aim: To determine whether functional impairments and autonomic symptoms are correlated in young people with developmental and epileptic encephalopathies (DEEs).

Method: Cross-sectional, online surveys (2018-2020) of parents recruited from family groups obtained information on several aspects of children's conditions including functional abilities (mobility, hand use, eating, and communication), 18 autonomic symptoms in six groups (cardiac, respiratory, sweating, temperature, gastrointestinal, and other), and parental stress. Bivariate and multivariable logistic regression analyses examined associations of dysautonomias with functional impairment, adjusted for type of DEE and age.

Results: Of 313 participants with full information on function and dysautonomias, 156 (50%) were females. The median age was 8 years (interquartile range 4-12y); 255 (81%) participants had symptoms in at least one autonomic symptom group; 283 (90%) had impairment in at least one functional domain. The number of functional impairment domains and of autonomic symptom groups varied significantly across DEE groups (both p<0.001). The number of functional impairment domains and of autonomic symptom groups were correlated (Spearman's r=0.35, p<0.001) on bivariate and multivariable analysis adjusted for DEE group and age. Parental stress was also independently correlated with dysautonomias (p<0.001).

Interpretation: Parent-reported dysautonomias are common in children with DEEs. They correlate with extent of functional impairment and may contribute to caregiver stress. What this paper adds Dysautonomic symptoms are common in young people with developmental and epileptic encephalopathies (DEEs). Burden of dysautonomias is strongly correlated with burden of functional impairments. Aspects of dysautonomic function may provide biomarkers of DEE disease severity.