Predictors of functional capacity as measured by the Glittre activities of daily living test in women with rheumatoid arthritis

Association between clinical, serological, functional and radiological findings and ventilatory distribution heterogeneity in patients with rheumatoid arthritis

BACKGROUND

In rheumatoid arthritis (RA), the involvement of the pulmonary interstitium can lead to structural changes in the small airways and alveoli, leading to reduced airflow and maldistribution of ventilation. The single-breath nitrogen washout (SBN2W) test is a measure of the ventilatory distribution heterogeneity and evaluates the small airways. This study aimed to find out which clinical, serological, functional and radiological findings are useful to identify RA patients with pathological values of the phase III slope (SIII) measured by the SBN2W test.

METHODS

This was a cross-sectional study in which RA patients were assessed using the Health Assessment Questionnaire-Disability Index (HAQ-DI) and the Clinical Disease Activity Index (CDAI) and underwent serological analysis of autoantibodies and inflammatory markers. In addition, they underwent pulmonary function tests (including the SBN2W test) and chest computed tomography (CT).

RESULTS

Of the 60 RA patients evaluated, 39 (65%) had an SIII >120% of the predicted value. There were significant correlations between SIII and age (r = 0.56, p<0.0001), HAQ-DI (r = 0.34, p = 0.008), forced vital capacity (FVC, r = -0.67, p<0.0001), total lung capacity (r = -0.46, p = 0.0002), residual volume/total lung capacity (TLC) (r = 0.44, p = 0.0004), and diffusing capacity of the lungs for carbon monoxide (r = -0.45, p = 0.0003). On CT scans, the subgroup with moderate/severe disease had a significantly higher SIII than the normal/minimal/mild subgroup (662 (267-970) vs. 152 (88-283)% predicted, p = 0.0004). In the final multiple regression model, FVC, extent of moderate/severe involvement and age were associated with SIII, explaining 59% of its variability.

CONCLUSIONS

In patients with RA, FVC, extent of lung involvement and age, all of which are easily obtained variables in clinical practice, identify poorly distributed ventilation. In addition, the presence of respiratory symptoms and deteriorated physical function are closely related to the distribution of ventilation in these patients.

Functional exercise capacity in rheumatoid arthritis unrelated to lung injury: A comparison of women with and without rheumatoid disease

BACKGROUND

Rheumatoid arthritis (RA) mainly affects the joints of the upper and lower limbs, so evaluating functional exercise capacity in individuals with RA via dynamic tests of the locomotor system is essential.

OBJECTIVES

To compare functional exercise capacity using the Glittre-activities of daily living (ADL) test (G-AT) in women with and without RA in the absence of RA pulmonary disease (RA-PD) and to correlate the findings with hand functioning, physical functioning, handgrip strength (HGS), and quadriceps strength (QS).

METHODS

This cross-sectional pilot study evaluated 35 women with RA and 25 healthy controls by assessing hand functioning using the Cochin Hand Functional Scale (CHFS), physical functioning with the Health Assessment Questionnaire Disability Index (HAQ-DI), muscle functioning using HGS and QS, and G-AT results.

RESULTS

Compared to the women in the control group, the women with RA presented higher scores for the CHFS (p< 0.0001) and HAQ-DI (p< 0.0001) and lower HGS (p< 0.0001) and QS (p= 0.013) values. The median G-AT time was higher in the RA patients than in the healthy controls [300 (295-420) vs. 180 (155-203) s], p< 0.0001), and the greatest difficulty reported by patients after the G-AT was squatting to perform the shelving tasks. G-AT time was positively correlated with the HAQ-DI (rs= 0.668, p< 0.0001) and CHFS (rs= 0.586, p= 0.0007) and negatively correlated with QS (rs=-0.429, p= 0.037). There was no significant correlation between the G-AT time and HGS.

CONCLUSIONS

Women with RA take longer to perform G-AT tasks. Moreover, G-AT time was associated with hand functioning, physical functioning and QS, but not with HGS.