Rationale:
GNAO1 pathogenic variants are associated with a spectrum of neurodevelopmental disorders including epilepsy and movement disorders. To more fully understand the spectrum of the disorder, the GNAO1 International Registry surveyed parents/guardians of individuals diagnosed with GNAO1-related disorders.
Method:
Patient recruitment was via social media and an email generated by the Bow Foundation, a non-profit charitable organization dedicated to GNAO1-related disorders. The survey was drafted by E.A with revision by members of the Bow Foundation Scientific Advisory Board and hosted on an online platform. All data were de-identified.
Results:
General characteristics
63 surveys were completed representing 5 continents with most from North America (40%) and Europe (14%). Age of first concern for abnormal symptoms was under one year in all patients with 73% citing concerns before 6 months. First abnormal symptoms were low muscle tone (70%), developmental delay (67%), seizure (25%) and abnormal movements (16%). All reported developmental delays. Feeding difficulties were common (49% beyond the neonatal period) with 24 participants requiring gastrostomy tubes. Movement disorders were reported in 76%, 14 of whom had required ICU admission for movements. Nine individuals have a deep brain stimulator targeting their abnormal movements.
Epilepsy characteristics
History of seizures was reported in 49% of participants. 24% of patients reported ongoing epilepsy. 16 participants (25%) reported a history of that resolved. In our cohort, at least 30% have overlap of seizure and movement disorders with an additional 7 patients with history of seizure “unsure” they had a movement disorder. Recurrent status epilepticus was reported by 12 individuals with >10 episodes in 6 individuals.
Conclusion:
This is the first parent-generated survey of this patient population. Individuals with GNAO1-related disorders presented with a range of clinical symptoms but uniformly have symptom onset before one year, most often before 6 months, and all have developmental delays. As described in the literature, movement disorders and epilepsy can be distinct but overlap in some individuals. Although epilepsy can present as an epileptic encephalopathy in this patient population, our findings suggest that not all GNAO1-related epilepsy will be medically refractory or lifelong.
Funding:
:None
FIGURES
Figure 1