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.