SAT0732-HPR Rating of perceived exertion in patients with rheumatoid arthritis – which are the correlates?
Authors: N. Brodin, N. Bobst, C.H. Opava
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> People with rheumatoid arthritis (RA) are recommended to participate in physical activity to improve or maintain their health. The intensity of the physical activity is important to gain the health benefits. One way for the individual to monitor the intensity of physical activity is to use the Borg scale for rating of perceived exertion (RPE), which is claimed to be strongly correlated to heart rate (HR). While this is true for healthy individuals, RPE in people with RA might however be influenced by a range of additional factors. <h3>Objectives</h3> To analyse correlates of RPE assessed at the end of an aerobic capacity test in patients with RA. <h3>Methods</h3> Data from 192 people with RA participating in the <sup>PARA 2010</sup> study were analysed. Their mean age was 59 years (SD 9.7), 159 (83%) were women, mean disease duration was 12 years (SD 9.4), mean DAS28 score was 2.95 (SD 1.25) and median Health Assessment Questionnaire (HAQ) score 0.375 (range 0–1.875). Submaximal tests of aerobic capacity on bicycle ergometers were performed according to the Åstrand protocol and perceived exertion was rated on the Borg RPE scale.<sup>6–20</sup> Data on the potential correlates pain (VAS, 0–100), fatigue (VAS, 0–100), general health perception (GHP, VAS, 0–100), lower extremity function (Timed Stands Test, TST, s), healthy physical activity levels (yes/no), activity limitation (HAQ, 0–3), fear avoidance beliefs (Fear avoidance beliefs questionnaire, FABQ, 0–24), exercise self-efficacy (Exercise Self Efficacy Scale, ESES, 6–60), and depression (EQ5D, question # 5, 1–3) were collected. Generalised linear models (GLM) with normal log models were used to calculate each variable's correlation with the RPE. Correlates with p-value&lt;0.10 were entered in a forward stepwise model. <h3>Results</h3> The correlation between RPE and working HR at the end of the aerobic capacity test was r<sub>s</sub>=0.15 (p&lt;0.05). Analysis using GLM identified general health perception, lower extremity function, activity limitation, depression, resting HR and working HR as correlates of RPE with p-value&lt;0.10. A forward stepwise model including these variables, together with age and gender, identified lower extremity function (OR: 1.0044/s, p=0.0001), resting HR (OR: 0.9977/beat, p=0.0071) and working HR (OR: 1.0030/beat, p&lt;0.0000) as correlates of RPE. <h3>Conclusions</h3> As expected, RPE correlated with working HR, but only weakly. Although our study participants were instructed to focus on perceived central exertion in their ratings, it seems that they were not able to distinguish that from peripheral exertion. Considering this bias in ratings, wearable HR monitors should be recommended to people with RA for accurate feedback on physical activity intensity. <h3>References</h3> [1] Borg GA. Psychophysical bases of perceived exertion. Med Sci Sports Exerc. 1982;14:377–81. [2] Nordgren B, Fridén C, Demmelmaier I, Bergström G, Opava CH. Long-term health-enhancing physical activity in rheumatoid arthritis – the PARA 2010 study. Study protocol. BMC Public Health2012;12:397. <h3>Disclosure of Interest</h3> None declared