Public health impact of risk factors for physical inactivity in adults with rheumatoid arthritis

Objective: To investigate the potential public health impact of modifiable risk factors related to physical inactivity in adults with rheumatoid arthritis (RA).

Methods: A cross-sectional study used baseline data from 176 adults with RA enrolled in a randomized controlled trial assessing the effectiveness of an intervention to promote physical activity. Accelerometer data were assessed for inactivity (i.e., no sustained 10-minute periods of moderate to vigorous intensity physical activity during a week's surveillance). The relationships between modifiable risk factors (motivation for physical activity, beliefs related to physical activity, obesity, pain, and mental health) and inactivity were assessed using odds ratios (ORs) and attributable fractions (AFs), controlling for descriptive factors (age, sex, race, education, disease duration, and comorbidity).

Results: More than 2 in 5 adults (42%) with RA were inactive. Factors most strongly related to inactivity were lack of strong motivation for physical activity (adjusted OR 2.85; 95% confidence interval [95% CI] 1.31, 6.20 and adjusted AF 53.1%; 95% CI 21.7, 74.6) and lack of strong beliefs related to physical activity (OR 2.47; 95% CI 1.10, 5.56 and AF 49.2%; 95% CI 7.0, 76.4). Together, these 2 factors are related to almost 65% excess inactivity in this sample.

Conclusion: These results support the development of interventions that increase motivation for physical activity and that lead to stronger beliefs related to physical activity's benefits, and should be considered in public health initiatives to reduce the prevalence of physical inactivity in adults with RA.