What Are the Predictors of Self-Reported Change in Physical Activity in Older Adults with Knee or Hip Osteoarthritis?

Background Although physical activity (PA) has been shown to be beneficial in older adults with osteoarthritis (OA), most show low levels of PA. This study evaluated if self-efficacy, attitude, social norm, and coping styles predicted change in PA in older adults with OA in the knee and/or hip. Methods Prospective study following 105 participants in a self-management intervention with baseline, post-test (6 weeks), and follow-up (6 months). Univariate associations and multivariate regression with self-reported change in PA as the dependent variable were measured. Potential predictors in the model: demographic, illness-related, and behavioral variables (attitude, self-efficacy, social norm, and intention), coping style, and pain coping. Results Forty-eight percent of participants reported increased PA at 6 weeks and 37% at 6 months which corresponded with registered PA levels. At 6 weeks, use of the pain coping style "resting," intention, and participation in the intervention was univariately and multivariately, positively associated with more self-reported change, whereas being single and less use of the pain coping style "distraction" predicted less change. Higher pain severity only predicted less change multivariately. At 6 months, univariate associations for age, general coping style "seeking support," and participation in the intervention were found; higher age was associated multivariately with less self-reported change. Conclusion At short term, self-reported change of PA was predicted by the behavioral factors intention and several pain coping styles. Together with other predictors of self-reported change (pain severity, higher age, being single), these could be addressed in future interventions for enhancing PA in older adults with OA.