Cardiorespiratory Responses during Graded Exercise in Woman with Systemic Lupus Erythematosus

Abstract

Systemic lupus erythematosus (SLE) is an inflammatory autoimmune disorder that affects all organs including the cardiorespiratory system. It is well-known that its parenchymal and vascular pulmonary lesions can lead to ventilatory restriction. Moreover, alterations in left ventricular function or structure have been identified in the disease. There are however, scarce data regarding cardiorespiratory responses (CR) in SLE patients. PURPOSE: To identify cardiorespiratory responses (CR) during graded exercise in SLE patients. METHODS: Sixteen consecutive SLE women (SLE) with systemic lupus erythematosus activity score (SLEDAI) <4, without cardiopulmonary involvement were selected and compared to 13 healthy women (CONTROL). All subjects performed a progressive treadmill cardiopulmonary test until exhaustion to determine the maximal aerobic capacity, ventilatory anaerobic threshold (VAT) and respiratory compensation point (RCP). RESULTS: Age (29.4 ± 1.4 vs. 25.8 ± 1.6 years, p=0.11) and body-mass index (23.9 ± 0.9 vs. 21.9 ± 0.5 Kg/m2, p=0.09) were alike between SLE and CONTROL groups. SLE had significant lower peak workload (4.6±0.2 vs. 5.6±0.1 mph, P<0.05) and relative aerobic fitness [VO2peak] (28.1±1.1 vs. 37.6±1.4 mL.kg-1.min-1, P<0.05). In addition, HR, O2 pulse, VE/VCO2 and Pet CO2 were significantly altered in SLE compared to CONTROL (Table). CONCLUSION: The novel finding of a decreased cardiorespiratory response in SLE probably associated to abnormalities in oxygen delivery system may be a relevant contributing factor to aggravate the known decreased aerobic capacity observed in these patients.