The pattern and timing of breathing during graded exercise test in systemic lupus erythematosus

Background: Systemic lupus erythematosus (SLE) is an inflammatory autoimmune disease that affects all organs including the respiratory system. Abnormal control of breathing during maximal voluntary ventilation has been recently identified in this disease. Purpose: To evaluate the pattern and timing of breathing at selected submaximal ventilatory stress in SLE. Methods: Twenty consecutive women (age: 28.8±1.0 years) with SLE were selected and compared to an age and BMI matched group of 19 healthy women (CTRL) (age: 26.2±1.3 years). All of the subjects performed a progressive treadmill cardiopulmonary test until exhaustion. Data were analyzed at absolute isoventilation (40, 60 and 80 L/min). Results: SLE presented lower relative aerobic fitness (VO2peak) (26.8±1.2 vs. 35.9±1.2 mL kg-1 min-1, p=0.001) than their healthy peers. View this table: Ventilatory parameters at different absolute isoventilation Conclusion: These results demonstrated a thachypnoeic breathing pattern and shorter timing of ventilation in SLE woman during exercise. This suggests that the reduced aerobic capacity observed in SLE patients may be accompanied by ventilation-perfusion mismatches.