Evaluation of six-minute walk test in juvenile systemic sclerosis

The objective is to evaluate the walking distance and oxygen desaturation during the six-minute walk test and to establish correlations between the test results and other clinical findings so to assess the reliability of the test for evaluation of children with juvenile systemic sclerosis (jSSc). A total of 25 jSSc, 27 juvenile systemic lupus erythematosus (jSLE), and 30 healthy controls were included. The test is conducted according to the guidelines recommended by the American Thoracic Society, standardized in 2002. Median values of walking distances were 470 (415-580) m in jSSc; 518 (376-618) m in jSLE; and 562 (493.5-618) m in healthy controls. jSSc patients walked significantly less distance comparing to controls (p<0.001). jSSc patients with lung involvement walked less than those without lung involvement [463.2 (418-565) m vs. 491.5 (415-580) m], but without a significant difference (p=0.82). The frequency of lower extremity pain during and after the test was significantly higher in the jSSc cohort compared to both control groups (p=0.001). Patients with myalgia were found to walk less than those without myalgia [446.5 (415-538) m vs. 493.5 (428-580) m] (p=0.04). Patients with jSSc have limited walking distances. Despite the decreased walking distance among jSSc patients with ILD and/or PAH, the limited number of patients makes the results inappropriate for interpretation. Low extremity pain influences the walking capacity of jSSc patients.