The quality of life of patients with lupus erythematosus influences cardiovascular capacity in 6-minute walk test

Objective: To assess the association between quality of life and distance walked in the 6-minute walk test (6MWT) in Brazilian premenopausal patients with systemic lupus erythematosus (SLE) and compare their results with those of healthy controls. Methods: Twenty-five premenopausal (18-45 years) patients diagnosed with low-activity SLE (mean SLEDAI: 1.52 +/- 1.61) and 25 controls were matched for age, physical characteristics, and physical activity level (International Physical Activity Questionnaire/s-IPAQ). Both groups should not be involved in regular physical activity for at least six months before the study. The 6MWT distance (American Thoracic Society protocol), posttest heart rate (HRpost), posttest oxygen saturation (SpO(2)post) and the Borg scale of subjective perception of effort (SPE/CR10) were evaluated. The quality of life was assessed by use of the Short Form Health Survey 36 (SF-36). Results: Patients with SLE had a significantly poorer quality of life, a shorter 6MWT distance (598 +/- 45 m versus 642 +/- 14 m, P < 0.001), and greater values of SPE/CR10 (6.28 +/- 2.0 versus 5.12 +/- 1.60, P <= 0.05) and HRpost (134 +/- 15 bpm versus 123 +/- 23 bpm, P <= 0.05) when compared with controls. The linear regression model suggested that quality of life was a significant predictor of 70% of the 6MWT distance. Conclusion: When compared with controls, patients with SLE walked a shorter distance in the 6MWT, which was associated with poorer quality of life.