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Updated: Jun 5, 2026

Measurements of Motor Function and Other Clinical Outcome Parameters in Ambulant Children with Duchenne Muscular Dystrophy
Published on: January 12, 2019
Indicators for ventilator use in Duchenne muscular dystrophy
Satoshi Hamada1, Yuka Ishikawa, Tomoyuki Aoyagi
1Department of Internal Medicine, National Organization Yakumo Hospital, 128 Miyazono-cho, Yakumo, Hokkaido 049-3198, Japan. sh1124@kuhp.kyoto-u.ac.jp
Simple lung function tests like respiratory rate/vital capacity (RR/VC) and respiratory rate/tidal volume (RR/TV) can predict the need for mechanical ventilation in Duchenne muscular dystrophy (DMD) patients. RR/VC is the most effective predictor.
Area of Science:
- Pulmonary Medicine
- Neuromuscular Disorders
- Medical Technology
Background:
- Duchenne muscular dystrophy (DMD) patients increasingly rely on continuous noninvasive mechanical ventilation.
- Assessing ventilatory function typically involves invasive and noninvasive tests.
- There is a need for simple, cost-effective parameters to gauge ventilator dependence in DMD.
Purpose of the Study:
- To evaluate the effectiveness of noninvasive lung function parameters in determining the extent of ventilator support required by DMD patients.
- To identify simple, inexpensive predictors of ventilator dependence.
Main Methods:
- 83 DMD patients were categorized into three groups: no ventilation, nocturnal ventilation, and full-time ventilation.
- Key parameters including tidal volume (TV), vital capacity (VC), respiratory rate (RR), and derived indices like RR/VC and RR/TV were measured.
- Receiver-operating-characteristic (ROC) curve analysis was employed to assess the diagnostic accuracy of each parameter.
Main Results:
- The respiratory rate/vital capacity (RR/VC) ratio demonstrated high accuracy (AUC > 0.92) in predicting nocturnal and continuous ventilator use.
- The respiratory rate/tidal volume (RR/TV) ratio and vital capacity (VC) also showed significant predictive value.
- Parameters like tidal volume/vital capacity (TV/VC), breathing intolerance index (BITI), and ventilator requirement index (VRI) were less effective.
Conclusions:
- Noninvasive lung function parameters, specifically RR/VC, RR/TV, and VC, are valuable and economical tools for predicting the need for mechanical ventilation in DMD.
- The RR/VC ratio emerges as the most suitable predictor for quantifying the extent of ventilator support required.
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