ABSTRACT
OBJECTIVE: Exercise testing can be used (i) to evaluate functional limitations of systemic sclerosis (SSc) and (ii) to study whether the inflammatory and oxidative systems are activated after a physical stimulus. The aim of this study was to determine exercise-induced inflammatory and oxidative responses in SSc compared with healthy subjects. METHODS: Eleven patients with SSc and pulmonary involvement and 10 healthy subjects underwent maximal cardiopulmonary exercise testing (CPET). Physiological responses were followed continuously during cycling. Blood samples were taken at rest, during and after maximal exercise to measure inflammatory and oxidative markers. RESULTS: In nine of the 11 SSc patients, cardiocirculatory limitation and gas exchange impairment limited exercise capacity. Basal inflammatory cells, interleukin (IL)-6, and oxidative stress were increased in SSc compared to healthy subjects and intensified after exercise. Basal and exercise-induced inflammation and oxidative stress were correlated with the modified Rodnan skin score. CONCLUSIONS: Although exercise capacity is impaired in patients with SSc, physical activity intensifies the already increased basal levels of systemic inflammation and oxidative stress. These data support the concept of a role for systemic inflammation and oxidative stress in the ongoing systemic effects of SSc.
