Physical and psychological symptoms limit physical activity for people with arthritis. This study examined if self-efficacy mediated a relationship between symptom and physical activity (PA) frequency change.
This was a secondary analysis of older adults with arthritis and joint pain in a trial of a lifestyle PA program (n = 339). Measures were depressive symptoms, pain, fatigue, arthritis self-efficacy, PA self-efficacy, and PA frequency. A panel model was used to analyze relationships at baseline and changes at 20 weeks.
The mean age was 68.8 years. At baseline, depression and fatigue were associated with arthritis self-efficacy (β = –.34 and –.24) and, in turn, PA self-efficacy (β = .63); PA self-efficacy was associated with PA (β = .15). Pain and depression changes were associated with arthritis self-efficacy change (β = –.20 and –.21) and, in turn, PA self-efficacy (β = .32) change; PA self-efficacy change was associated with PA change (β = .36).
Change in symptom severity affected change in PA frequency. These relationships appeared to operate through self-efficacy. Over time, pain appeared to have a stronger relationship than fatigue with self-efficacy and PA. These findings support strategies to help people with arthritis strengthen their confidence for symptom coping and PA participation.
Sperber is with General Internal Medicine, Duke University, Durham, NC. Hall is with the Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Durham, NC. Allen is with Durham Center for Health Services Research in Primary Care, VA HSR&D, Durham, NC. DeVellis is with the Dept of Health Behavior and Health Education, Gillings School of Global Public Health, University of North Carolina, Durham, NC. Lewis is with the Health Communication Program, RTI International, Research Triangle Park, NC. Callahan is with the Thurston Arthritis Research Center, University of North Carolina at Chapel Hill.