Reduction of sleep-disordered breathing after physostigmine

Area of Science:

• Sleep Medicine
• Pharmacology
• Respiratory Medicine

Background:

• Obstructive sleep apnea (OSA) is a common disorder characterized by repeated episodes of upper airway collapse during sleep.
• Current treatments for OSA have limitations, necessitating the exploration of novel therapeutic approaches.

Purpose of the Study:

• To investigate the efficacy of physostigmine (PHYS), a cholinesterase inhibitor, in treating moderate to severe obstructive sleep apnea (OSA).
• To assess the impact of PHYS on apnea/hypopnea index (AHI), oxygen saturation (SaO2), and sleep architecture in OSA patients.

Main Methods:

• A double-blind, placebo-controlled, randomized crossover trial involving 10 male patients with moderate to severe OSA.
• Patients received a 7-hour infusion of PHYS (0.12 microg/minute/kg) or placebo.
• Apnea/hypopnea index (AHI), minimum SaO2, and sleep stages (REM and non-REM) were monitored.

Main Results:

• PHYS significantly reduced the mean AHI by 21.4% and increased minimum SaO2 by 23.2%.
• A notable reduction in non-REM sleep AHI (14.9%) and REM sleep AHI (67.5%) was observed.
• Sleep shortening occurred, but greater AHI reduction correlated with less sleep time reduction. Nocturnal heart rate decline was also reduced.

Conclusions:

• Physostigmine demonstrates a significant, predominantly REM-related, reduction in obstructive sleep apnea severity.
• PHYS may represent a potential new therapeutic strategy for OSA, warranting further long-term investigation.
• Correlations suggest that baseline heart rate and BMI may influence treatment response in OSA patients.