Abstract
The energy consumption from the aspect of physiological respiratory metabolismwas investigated in patients with RA. Three male and 27 female patients with self-locomotive ability and without pneumocirculatory dysfunction and hepatorenal disorder were chosen from outpatients with RA: Ten healthy volunteers were used as a control group. The experiment was performed by a modification of the Majima's tread mill method. The expiratory gas was analyzed and the heart rate was recorded with an electrocar Biographic monitor at varying belt-speeds and slopes of the tread mill to investigate the relation between the minute heart rate and oxygen uptake (VO2) .
When the minute oxygen uptake in response to a certain heart rate was used as an index of the physical strength, the index was significantly reduced in RA patients compared to healthy subjects. When analyzed by the class, the index was inversely related with the class and was remarkably reduced in class 3. The pattern of 24-hr heart rate demonstrated a higher ratio of heart rate at rest in patients with higher class, suggesting a reduction of activity in daily life.
