Respiratory Changes in Multiple Sclerosis

INTRODUCTION

There is a paucity of literature to guide physical therapists as to how to evaluate and treat persons with multiple sclerosis (MS). This may have resulted in physical therapists being uncomfortable and reluctant to work with patients with this diagnosis. Fry et al¹ are therefore to be commended for an important addition to the small but growing body of literature on physical therapy evaluation and treatment of patients with MS. Although other authors have documented diminished respiratory function in persons with fairly advanced MS, evaluation of respiratory status in persons with relatively mild MS is not always considered. Due to the often progressive nature of MS, as well as the fact that mortality in MS is most often related to respiratory issues, early detection and treatment of respiratory issues are strongly indicated.

Fry et al confirm the results of other researchers, finding that persons with relatively mild MS display signs of both inspiratory and expiratory dysfunction. It is not known whether the respiratory dysfunction is due to the disease itself or a secondary effect of disease-induced inactivity, but testing for signs of pulmonary dysfunction in all patients with MS, regardless of the level of impairment, is clearly indicated. Fry and colleagues use sophisticated pulmonary testing equipment in their experiment, which is generally not available to most clinicians. A simple and clinically expedient way to measure pulmonary dysfunction, as suggested by Smeltzer et al² may be more appropriate for the clinician, although the tool of Smeltzer et al is geared toward expiratory dysfunction rather than the inspiratory dysfunction studied by Fry et al.

A common problem for physical therapists who treat persons with MS is termed therapeutic nihilism, or the belief that given the patient's condition, there is little meaningful difference that physical therapy can make. However, Fry et al have demonstrated that patients with MS and inspiratory muscle impairment respond well to a simple inspiratory muscle training program. Given the lack of information on physical therapy interventions for persons with MS, the simplicity and effectiveness of this intervention are impressive. It is also worth noting that the device used for the inspiratory muscle training (threshold inspiratory muscle trainer) is relatively inexpensive and easy to obtain and use.

The study does raise further clinical questions and issues. Does respiratory muscle training need to be ongoing for patients with MS, over the course of the disease, or are only brief interventions required? This goes to the issue of whether MS-related pulmonary dysfunction is a primary disease characteristic or secondary to disease-related inactivity. Another question worth asking is what might be the overall effect of improved pulmonary function in this patient population? It could result in improved exercise and functional performance, decreased complaints of fatigue, or a lower incidence of pulmonary morbidity. Follow-up studies on this topic would be of interest to clinicians treating individuals with MS.