Background Rheumatoid Arthritis (RA) is a chronic pain condition which limits the ability of patients to function normally and therefore decreases their physical activity levels . Physical activity is difficult to assess, as subjective measures of activity are often inaccurate . Actical accelerometers have been developed to objectively assess physical activity levels.
Objectives Our study therefore aimed to use accelerometry to objectively assess habitual physical activity levels in a group of female patients with RA, and to compare these measures to health related quality of life and disease activity indices.
Methods Seventy-two black, female participants were recruited for this study with a mean age of 47±12 years. Fifty patients confirmed as having RA, were recruited from a local hospital and were divided into a physically active group (n=25) and a physically inactive group (n=25) according to the median of their average activity counts recorded on the accelerometer over a two week period. Twenty-two participants were healthy age and socioeconomically matched controls. All participants wore an Actical on their right hip for two weeks during the day. Participants with RA were also assessed for disease activity using the Simplified Disease Activity Index (SDAI) and completed the Short Form-36 (SF-36) and the modified Health Assessment Questionnaire (HAQ-DI). All Acticals were calibrated before the data were analysed.
Results The physically inactive group spent significantly more time in sedentary activities than did the physically active group (p=0.003) or the control group (p<0.0001), and significantly less time in light and moderate activities than both the physically active group and the control group. The mean HAQ-DI score in the patients with RA was 1.32±0.92, and was significantly greater in the physically inactive group than in the physically active group (p<0.0001), indicating a greater degree of functional impairment. The mean SDAI score in the RA group was 15.96±10.83, yet there were no differences between the two groups for SDAI. The physically active group scored better than the physically inactive group on every component of the SF-36, and significantly better for vitality (p=0.039), composite mental health (p=0.049), composite physical health (p=0.049), and total SF-36 score (p=0.026).
Conclusions Accelerometry is able to detect habitual physical activity in patients with RA, and indeed confirmed that patients with RA lead a significantly more sedentary lifestyle than healthy controls. Higher levels of physical activity were not associated with RA disease activity, but were protective of functional capacity and highly associated with improved health related quality of life in RA patients.
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Disclosure of Interest None Declared