Clinical and instrumental gait phenotyping in subjects with GLUT-1 deficiency syndrome

This is a cross sectional, case - control study.

Thirty-four patients have been screened between January 2023 and April 2024.

The final study population consisted of 32 GLUT1DS subjects (13 males, 40.6%).

The mean age at clinical onset was 2.6±2.7 years, being the seizures the most common type of clinical onset (26 subjects, 81.2%), followed by movement disorders (3 subjects, 9.4%) and paroxysmal eye movements (3 subjects, 9.4%). 

The age at definitive diagnosis was 13.4±12.0 years.

At the study enrolment subjects were cognitively impaired, with a mean IQ of 66.0±20.6. Epilepsy was a common clinical finding in this cohort: 7 (21.9%) subjects were on anti-seizure medication, while 14 (43.7%) had seizures during the past 6 months.

The primary objective of the study was to assess the difference in inertial gait analysis between GLUT1DS patients and HS. As co-primary outcomes we considered the Harmonic Ratio value and the short-time maximal Lyapunov’s exponent.

As secondary outcomes, we planned to evaluate the difference in values of the other trunk acceleration – derived gait indexes.

Since we also performed a comprehensive descriptive phenotyping of gait variables and clinical features of GLUT1DS, we also looked for potential correlations between these features and the instrumental indexes.