Sleep and physical activity: a cross-sectional objective profile of people with rheumatoid arthritis

Regular physical activity (PA) is important for people with rheumatoid arthritis (RA). Poor sleep is a common complaint among people with RA, which may have an influence on their PA levels. There is a lack of objective information regarding total sleep time (TST) and PA duration in this population. A cross-sectional study design was used. SenseWear Pro3 Armband(R)TM is used to measure TST and total PA duration. Four valid days, with 95% wear time necessary for inclusion in final results. Disease activity and function were measured using the DAS-28, HAQ and VAS. Data analysis carried out using SPSS v22. Seventy-five (75) participants completed monitoring period, with 51 (68%) meeting modified PA duration guidelines. Data with 95% wear time over a minimum of 4 days were available for 32 recorded participants, with a mean TST of 5.7 (SD_1.11) hours per night and a median 1.25 (IQR_1.88) hours of daily PA. TST had a positive significant relationship with PA (p = 0.018); PA demonstrated a negative significant relationship with functional limitations (p = 0.009) and correlated with lower CRP levels; CRP levels had in turn a significant relationship to global health (p = 0.034). Total sleep time was low for people with RA. People with RA who are more physically active have longer TST. These findings provide an objective profile of TST and PA duration in people with RA and suggest a relationship between increased PA duration and longer TST. Further research is needed to confirm these novel findings.