An examination of self-report physical activity and its relationship with psychological factors in inflammatory arthritis

Background: Inflammatory arthritis (IA) is the term given to a group of chronic inflammatory rheumatic diseases that primarily include rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Physical activity (PA), defined as any bodily movement produced by skeletal muscles that results in energy expenditure (EE), is important for everyone, including people with RA and PsA. Despite the importance of including PA in the management of these two inflammatory conditions decreased levels of PA have been reported for people with RA. In order to develop interventions aimed at increasing PA in IA determination of the factors associated with PA participation in this population is warranted. Aim: Thus the aim of this thesis was to establish a self-report PA profile of the Irish RA and PsA populations and also to establish the correlates of PA for these two populations. Methodology: Initially a systematic review of the literature was conducted, examining the correlates of PA in the RA and PsA populations. The review found that there are a number of correlates relating to PA in people with RA; however none have been definitively determined. Secondly a cross-sectional study of 102 people with IA, recruited from rheumatology outpatient clinics, was conducted to explore the self-report levels of PA and EE within the IA population. Levels of PA were examined using the Yale Physical Activity Survey (YPAS), a self-report measure of PA. Socio-demographic variables were recorded, in addition to self-efficacy, beliefs about PA, illness perception and general health perceptions. Statistical analysis consisted of descriptive statistics to establish the profiles of PA, EE and other variables, and correlational and hierarchical regression analysis to explore the statistical relationships between PA, EE and the independent variables. Results: Total PA levels over the past week for males were 21.7 hours and for females was 24.6 hours. Levels of self-report PA and EE in the IA population were low and were similar to those reported in other arthritis populations. Age was the only socio-demographic variable to correlate with PA over the past month (r=-0.02, p=0.04). Physical health perception correlated with PA levels (r=0.227, p=0.02) and EE over the past week (r=0.248, p=0.01). Beliefs about PA were shown to correlate with levels of self-report PA and EE, and remained significant when age (p=0.03) and physical health perception (p=0.02) were controlled for. Conclusion: Levels of PA in this population were low. Age was the only significant socio-demographic correlate of PA. Beliefs about PA and physical health perception influenced levels of PA and EE in the group. Future research should explore the impact of an intervention aimed at altering beliefs about PA and health perceptions and the influence of this intervention on levels of PA in the IA population. Additionally PA, self-efficacy, beliefs about PA, illness perception and health perception should be examined in a larger sample of the PsA population.