Developmental origins of self-reported arthritis and osteoarthritis: new england family study

Abstract

focused primarily on walking behavior. Daily step count recording with a pedometer offers a low cost convenient method of quantifying the amount of walking-related physical activity. The purpose of this study was to identify the role of psychological factors in determining average daily step count among people with painful knee OA. Methods: Our sample consisted of 166 people with painful knee OA: aged >1⁄4 50 years, visual analogue scale for pain >1⁄4 40/100, radiographic Kellgren & Lawrence grade >1⁄4 2, and Western Ontario & McMaster Physical Function (WOMAC PF) >1⁄4 25. A multiple regression analysis was carried out with average daily step count recorded over 7 days using a pedometer as the dependent variable. Psychological variables were entered as independent variables after entering age, body mass index, pain (WOMAC pain score), and physical function (WOMAC PF score) as covariates. These demographic variables are known to be associated with physical activity in knee OA. Psychological variables included the subscales of the Depression, Anxiety & Stress (DASS) scale (Depression, Anxiety and Stress), Arthritis Self-Efficacy scale (pain, function and other), Pain Catastrophizing Scale (Rumination, Magnification and Helplessness) and Attitudes to Physical Activity Scale (Self-efficacy, barriers and benefits). Results: DASS Stress subscale accounted for 6% of the variance in step count after accounting for the covariates (15% of variance) and was the only significant psychological contributor (b 1⁄4 -0.25, SE 1⁄4 52.3, p < 0.05). Higher levels of stress were associated with lower daily step counts. Conclusion: After controlling for demographic and symptomatic variables, only stress was associated with average daily step count. Our findings are consistent with previous studies showing no associations between depression or anxiety and physical activity levels of people with knee OA. The findings indicate that stress may be an important psychological factor that needs to be addressed in order for people with knee OA to increase their amount of daily walking as a means to becoming more physically active.