More time spent in moderate-to-vigorous physical activity and sleep is associated with a lower incidence of hip or knee osteoarthritis.

INTRODUCTION

Osteoarthritis is the second most prevalent musculoskeletal disorder and mostly affects hip and knee joints. Movement behaviours have been associated with the incidence of osteoarthritis. However, previous studies have mainly relied on self-reported questionnaires. Moreover, the inherently compositional nature of 24-hour movement behaviours has not yet been considered.

OBJECTIVE

This prospective study aims to investigate the association between objective device-measured movement behaviours and incident hip and knee osteoarthritis, accounting for the compositional nature of movement behaviours.

METHODS

Data from the UK Biobank cohort were used, which included individuals aged 40-69 years old. Seven days movement behaviours were measured with a wrist-worn triaxial accelerometer. Incident hip and knee osteoarthritis cases were prospectively ascertained on hospital inpatient data. Compositional Cox proportional hazard models were used.

RESULTS

85 706 individuals were included in the study between 2013 and 2015. During a mean follow-up of 7.6 years, 5308 participants were diagnosed with hip and knee osteoarthritis. Results showed that reallocating 30 min/day to moderate-to-vigorous physical activity from sedentary time (HR=0.98, 95% CI 0.97 to 0.99) or from light physical activity (HR=0.94, 95% CI 0.92 to 0.96) was associated with lower incidence of hip and knee osteoarthritis. Similarly, reallocating 30 min/day to sleep from sedentary time (HR=0.97, 95% CI 0.96 to 0.99) or from light physical activity (HR=0.93, 95% CI 0.92 to 0.95) was associated with lower incidence hip and knee osteoarthritis.

CONCLUSION

Using objective measures of movement behaviours, this study provides evidence that moderate-to-vigorous physical activity and sleep may play important roles in hip and knee osteoarthritis prevention, while accounting for the other movement behaviours. Further research is needed to understand whether the associations are causal.