Multiple sclerosis (MS) is a primary disorder of the central nervous system that can affect motor pathways and cause muscle weakness. If respiratory pathways are affected, respiratory muscle weakness contributes to poor cough performance, which can lead to aspiration, pneumonia and ventilatory failure.

After establishing the respiratory and pulmonary status of advanced MS patients, expiratory muscle training (EMT) is tested for its effect on respiratory muscle function, forced vital capacity (FVC) and cough efficacy.

• In multiple sclerosis, respiratory pathways are often affected, leading to respiratory muscle weakness and inefficient cough function.

• Impaired cough performance increases the risk of aspiration, pneumonia and ventilatory failure.

• Respiratory muscle weakness and inefficient cough contribute to increased morbidity and mortality in advanced MS patients.

• Assessment of the pulmonary and functional status of advanced MS patients revealed significantly reduced respiratory muscle strength, pulmonary function, cough efficacy, and functional status.

• 3 months of respiratory muscle training (RMT) significantly improved cough efficacy and slightly increased respiratory muscle strength in MS patients.
• RMT effectively improves cough efficacy in advanced MS patients, reducing the risk of aspiration, pneumonia and respiratory failure.

Methods

This study in two parts first examines the pulmonary function, cough efficacy, functional status, and respiratory muscle strength in 28 bedridden or wheelchair-bound MS patients, and analyzes correlation between the outcomes. Outcomes include FVC, pulmonary index (PI, cough efficacy)), extended disability status scale (EDSS), maximum inspiratory pressure (PImax), maximum expiratory pressure (MEP), and neck flexion strength.

In part two, PImax, PEmax, PI, and FVC were assessed before and after 3 months of EMT in 21 bedridden or wheelchair-bound MS patients.

Study Results

The first part of the study revealed that FVC, PI, cough efficacy, PImax, and PEmax were severely reduced in MS patients. Significant correlations were observed between PEmax and cough efficacy, functional status and FVC.

EMT resulted in significantly improved PI, and increased PImax and PEmax (not significant). The effect on PI was still observed after 3 months.

Conclusion

Patients with advanced MS have severely reduced pulmonary function and respiratory strength. Respiratory muscle training significantly improves immediate and long-term cough efficacy.

References

Gosselink R, et al. Respiratory muscle weakness and respiratory muscle training in severely disabled multiple sclerosis patients. Arch Phys Med Rehabil. 2000 Jun;81(6):747-51.