Respiratory motor function in individuals with centronuclear myopathies

Area of Science:

• Neurology
• Pulmonology
• Rare Diseases

Background:

• Centronuclear myopathies (CNMs), including X-linked myotubular myopathy (XLMTM), frequently lead to severe respiratory insufficiency requiring early life support.
• Quantitative data on respiratory motor function in CNM patients are limited.

Purpose of the Study:

• To evaluate mechanical ventilation (MV) reliance, ventilatory kinematics, unassisted tidal volumes, and maximal respiratory pressures in individuals with CNMs.
• To investigate the relationship between MV dependence duration and respiratory muscle strength in CNM patients.

Main Methods:

• Assessed 14 individuals with CNMs (10 with XLMTM).
• Measured reliance on MV, ventilatory kinematics, unassisted tidal volumes, and maximal respiratory pressures.
• Correlated years of MV dependence with maximal expiratory pressures (MEP).

Main Results:

• Thirteen participants required full-time, invasive MV.
• Maximal inspiratory pressures were significantly higher in those with at least 1 hour/day of unassisted breathing compared to 24-hour MV users.
• Years of MV dependence showed a significant negative correlation with MEP (r = -0.715, P < 0.01).

Conclusions:

• Respiratory function in CNMs may be influenced by deconditioning from prolonged MV and/or inherent differences in respiratory muscle strength.
• Findings can aid in assessing severe respiratory insufficiency in neuromuscular clinical care and research.