NEW YORK (Reuters Health)—Inspiratory muscle training can help improve aerobic capacity and pulmonary function in patients with ankylosing spondylitis (AS), according to new findings presented at the European League Against Rheumatism Annual Congress.
“Inspiratory muscle training as a stand-alone therapy improves inspiratory muscle function (strength and endurance), decreases symptoms of dyspnea and improves exercise capacity,” Dr. Razvan Dragoi of “Victor Babes” University of Medicine and Pharmacy in Timisoara, Romania, and Dr. Claudiu Avram of West University of Timisoara told Reuters Health via email. Dr. Dragoi presented the findings at the meeting June 12 in Rome.
AS is a painful and progressive disease caused by chronic inflammation of joints in the spine, with a prevalence of about 32 per 10,000 people in North America and 24 per 10,000 in Europe. Up to 80% of AS patients have impaired lung function and reduced pulmonary muscle strength and endurance.
While inspiratory muscle training (IMT) has been shown to be helpful in heart failure, chronic obstructive pulmonary disease, morbid obesity, and restrictive thoracic disease, Dr. Dragoi and Dr. Avram said, it has not yet been tested in AS patients.
In the new study, the two researchers and their colleagues randomly assigned 54 patients with AS to receive either eight weeks of conventional rehabilitation exercise training and IMT, or eight weeks of conventional rehab exercise only. Patients in the IMT group performed three 30-minute sessions per week using a real-time computer-assisted device (Trainair, Project Electronics Limited, UK).
Patients who received IMT showed significantly improved chest expansion (from 0.66 cm at baseline to 0.94 cm at eight weeks). Their forced vital capacity improved from 78.6% to 82.7%, while forced expiration volume in one second increased from 71% to 74.6%.
IMT training also improved peak oxygen uptake from 1.7 to 2 L/min, while lowest effort ventilatory equivalent ratio for carbon dioxide decreased from 29 to 26.6.
The patients in the control group had a borderline significant improvement in chest expansion, from 0.69 cm to 0.72 (p=0.032) but showed no significant improvements in any other studied parameters.
“Inspiratory muscle training is a feasible treatment option in patients with pulmonary dysfunction due to ankylosing spondylitis,” Dr. Dragoi and Dr. Avram said via email. While the investigators have not followed up to see whether the benefits of IMT persisted, “we consider that a session of 30 minutes per week could be enough to maintain the gained benefits,” they said.
Patients can be taught to safely use the Trainair device at home, the researchers said.