Abstract

Background/Purpose: Sedentary behavior is associated with increased risk of functional decline and disability. Individuals with rheumatoid arthritis (RA) spend more time in sedentary activity than healthy adults. Despite the association of RA with other deleterious health states, the assessment of sedentary behavior in clinical settings has not been well-developed in this patient population. We examined 3 potential approaches to identify the most sedentary individuals in adults with RA using a modified version of the Yale Physical Activity Survey (YPAS).

Methods: 172 adults with RA were enrolled in IMPAACT (Improving Motivation for Physical Activity in Arthritis Clinical Trial). Participants wore an accelerometer for 7 days then completed the modified YPAS for the same 7-day accelerometer period. Daily sedentary time was estimated from YPAS in three ways: 1) a categorical estimate of hours/day spent sitting (<3, 3-6, 6-8, >8 hrs/day); 2) a subjective continuous estimate of sedentary time calculated by subtracting hours sleeping and time spent in physical activity from a 24-hour day; and 3) rank order of the subjective continuous estimate. Each estimate was compared to objective accelerometer-derived sedentary time, defined as time registering counts of less than 100/minute during waking hours.

Results: On average, the 172 participants had RA for 13 years. Mean Disease Activity Score-28 was 6.4 and mean age was 55 years. 83% were female. Accelerometer-derived sedentary time was greater than 8 hours/day in 93% of participants. The 4 sitting categories had a significant increasing linear trend with objective sedentary time but over half the participants categorized themselves as sitting more than 8 hours/day. A significant linear relationship was observed between the continuous YPAS-derived sedentary time and objective sedentary time (Pearson r = 0.29, p<0.001); but a Bland-Altman plot demonstrated systemic bias. There was a significant linear relationship between the ranked YPAS-derived continuous estimate and ranked accelerometer sedentary time (Spearman = 0.26, p <0.001). Rank-order was an unbiased predictor.

Conclusion: All three approaches showed a significant relationship between self-reported and objectively measured sedentary time. The self-reported sitting category might be more informative with a category to capture sitting > 10 hours/day. The continuous YPAS-derived sedentary time estimate was a biased estimator. The unbiased rank of the YPAS-derived continuous sedentary the best use of the detailed YPAS information. This patient-reported approach using the modified YPAS shows promise to be a useful tool to identify the most sedentary patients at highest risk for functional decline. Providing a practical and accurate tool to identify the most sedentary individuals could lead to increased awareness and patient monitoring of sedentary behavior by clinicians.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/self-reported-sedentary-behavior-in-patients-with-rheumatoid-arthritis/