Objective: It has been reported that patients with fibromyalgia syndrome (FMS) have lower maximal respiratory pressures than healthy subjects, indicating reduced pulmonary muscle strength. It has also been reported that patients with FMS have reduced grip strength. In this study, we aimed to examine the possible relationship between handgrip strength as a determinant of peripheral muscle strength and pulmonary muscle strength in patients with FMS by comparing them with healthy controls.
Methods: Forty-one consecutive women with FMS (diagnosed according to the American College of Rheumatology 1990 criteria) were compared with 40 age- and body mass index-matched healthy female controls. Pulmonary function tests were assessed by spirometry. Maximal pulmonary pressures were evaluated using an oral pressure meter. A dyspnea score was obtained. Pain was scored according to visual analogue scale and chest pain was classified (0-9) in fibromyalgia patients. Chest expansion was also measured in the two groups. Tender points were also evaluated in FMS patients. Grip strength (Jamar handheld dynamometer) was also measured in the two groups.
Results: The difference in pulmonary function tests was not statistically significant between groups. Maximal respiratory pressures (maximum inspiratory pressure and maximum expiratory pressure) and endurance (maximum ventilatory volume) were significantly lower in patients with FMS than in controls. There was also a statistically significant difference between groups regarding grip strength. There was also significant correlation between maximal inspiratory pressure and maximal expiratory pressure values and handgrip strength in patients with FMS.
Conclusion: These data indicate that handgrip strength may be a determinant of pulmonary muscle strength in fibromyalgia patients.