Nitrous oxide-induced predominantly motor neuropathies: a follow-up study

Area of Science:

• Neurology
• Toxicology
• Clinical Medicine

Background:

• Recreational nitrous oxide (N2O) abuse is a growing concern among young individuals.
• N2O abuse can lead to severe neurological complications, including neuropathy.
• Understanding the long-term effects of N2O-induced neuropathy is crucial for patient management.

Purpose of the Study:

• To systematically evaluate the clinical, electrophysiological, and biological outcomes of patients with neuropathy caused by recreational nitrous oxide abuse.
• To assess the recovery and long-term disability following cessation of N2O use.

Main Methods:

• Retrospective case series of seven patients aged 18-30 with N2O-induced neuropathy.
• Data collection included demographic, toxicological, clinical, biological, and electrophysiological parameters.
• Functional outcomes were assessed at initial and follow-up examinations.

Main Results:

• Patients developed severe, progressive, predominantly motor axonal neuropathy and myelopathy after extensive N2O balloon consumption.
• Nerve conduction studies showed active denervation in the lower limbs; homocysteine levels were elevated while cobalamin levels were normal.
• Short-term recovery was partial, with persistent motor deficits and ataxia at a median follow-up of 9.2 months.

Conclusions:

• Young patients with N2O-induced motor neuropathy experience significant and persistent disability even after prolonged abstinence and vitamin B12 supplementation.
• The severity of these toxic neuropathies warrants longer follow-up to fully understand their long-term impact.
• Early identification and intervention are critical for managing N2O-related neurological damage.