Clinical determinants and chronotrophic responses of maximal exercise capacity in patients with early stage of sarcoidosis

Background: Patients with early stage of sarcoidosis have reduced exercise capacity however; studies investigating the determinants of maximal exercise capacity and patients9 chronotropic responses to maximal exercise are limited. Aim: To investigate the clinical determinants and chronotrophic responses of Modified incremental shuttle walk test (ISWT) in patients with early stage of sarcoidosis. Methods: Thirty-four patients with sarcoidosis (46.58±10.30 years) were included. Pulmonary functions were measured. Maximal exercise capacity was evaluated using Modified ISWT, respiratory muscle strength (MIP, MEP) using a mouth pressure device, peripheral muscle strength using dynamometer, dyspnea using Modified Medical Research Council (MMRC) dyspnea scale and fatigue using Fatigue Severity Scale (FSS). Results: There were statistically significant correlations between Modified ISWT distance and age, shoulder flexor, quadriceps strength, MlP, MEP, dyspnea and fatigue perception (p Conclusion: Upper extremity muscle strength and fatigue are factors significantly contributing to impaired maximal exercise capacity, and chronotropic incompetence is prevalent in patients with sarcoidosis. Maximal exercise capacity worsens with decreasing peripheral and respiratory muscle strength. The effects of exercise training on maximal exercise capacity and chronotrophic response should be investigated.