Basic indicators of energy metabolism in patients with rheumatoid arthritis evaluated by indirect calorimetry
Abstract
The objective of the investigation was to examine basic parameters of the energy metabolism (energy expenditure at rest (REE), the respiratory quotient (RQ) and evaluate their relationship with age, basic parameters of the activity of the disease, serum positivity, basal therapy and corticoid therapy in patients with rheumatoid arthritis. The investigation comprised 26 patients with rheumatoid arthritis selected at random, incl. 12 serum positive ones.
The mean age af the patients was 62.2 +/- 11.0 years, BMI 26.65 +/- 4.35, the mean duration of the disease was 11.8 +/- 9.9 years (range 1-36 years). A total of 12 patients had basal therapy, 12 patients took glucocorticoids regularly.
The examination comprised a record of the case-history, clinical examination (Thompson's articular index), REE was evaluated by indirect calorimetry. The assessed REE value was compared with the expected value calculated according to Harris-Benedict's empirical formula (BMR) and expressed in per cent of the calculated value (REE%).
The respiratory quotient (RQ) was calculated from the assessed CO2 and O2 consumption. The authors found a close correlation between REE and REE% (r = 0.606, p < 0.01) but no correlation between BMR and REE% (r = 0.115).
The above parameters did not differ in serum positive and serum negative patients with RA treated with corticoids and those without corticotherapy, only in patients with basal therapy there are statistically significantly higher REE values (6456.7 +/- 790.5 kJ/24 h vs. 5396.4 +/- 826.7 kJ/24 h, p < 0.01) and REE% (110.6% +/- 99.2%, p < 0.05), as compared with subjects without basal therapy.