Huntington disease: early indentification by H reflex testing

Area of Science:

• Neurology
• Neuroscience
• Clinical Electrophysiology

Background:

• Huntington disease (HD) is a progressive neurodegenerative disorder.
• Early detection of Huntington disease is crucial for management and counseling.
• The H reflex of Hoffmann is a neurophysiological measure that can assess nerve pathway integrity.

Purpose of the Study:

• To evaluate the utility of the H reflex of Hoffmann for early detection of Huntington disease.
• To compare H reflex responses in individuals with Huntington disease, those at risk, and healthy controls.

Main Methods:

• Deep peroneal nerve stimulation was performed using a monopolar needle electrode.
• Muscle potentials (M response and H reflex) were recorded from the anterior tibialis and extensor digitorum brevis muscles.
• Subjects included 9 with Huntington disease, 8 at-risk offspring, and 30 controls.

Main Results:

• The H reflex was present in 8/9 Huntington disease patients and 5/8 at-risk individuals.
• Only 1/30 control subjects exhibited a unilateral H reflex.
• A significant difference in H reflex presence was observed between the patient/at-risk groups and controls.

Conclusions:

• H reflex testing shows potential for early identification of individuals at risk for Huntington disease.
• This neurophysiological marker could aid in family counseling and understanding Huntington disease.
• Further research is warranted to confirm the diagnostic value of the H reflex in Huntington disease.