1 Movement Physiology Research Laboratory, University of the Witwatersrand, Johannesburg, South Africa.
2 Arthroplasty Unit, Division of Orthopaedic Surgery, Charlotte Maxeke Johannesburg Academic Hospital, Johannesburg, South Africa.
3 Sleep, Cognition and Neuroimaging Laboratory, Department of Health, Kinesiology and Applied Physiology, Faculty of Arts and Sciences, Concordia University, Montreal, Quebec, Canada.
4 Department of Exercise Sciences, The University of Auckland, New Zealand.

Purpose: This study aimed to investigate the relationship between cardiometabolic disease risk and time spent in device-measured activity behaviours in a cohort of people with advanced osteoarthritis (OA) awaiting joint replacement surgery.

Materials and methods: Cardiometabolic risk biomarkers were assessed in people with OA (n = 96; hip n = 38, knee n = 58; mean (SD) age = 64.3 (9.8) years; 71% female). Physical activity (PA) and sedentary behaviour (SB) were measured by accelerometer over seven days (24 h/day).

Results: There were similar patterns of PA and SB between the hip and knee OA participants except for total number of steps (hip = 3365 (2926) vs knee 4344 (2836) steps/day; p = 0.018) and total stepping time (hip = 50.8 (38.2) vs knee = 67.2 (38.5) min/day; p = 0.005). Each additional cardiometabolic risk factor accumulated was associated with a 26.3 min/day increase in sedentary behaviour (p = 0.032; 95% CI: 2.3, 50.2), a 26.3 min/day decrease in upright time (p = 0.032; -50.2, -2.3) and a 23.6 min/day decrease in standing time (p = 0.032; -45.1, -2.1).

Conclusions: In people with hip or knee OA, increased cardiometabolic disease risk was associated with more sitting and less upright and standing time. Findings support targeting reductions in sedentary behaviour for improvements in cardiometabolic health in people with osteoarthritis.IMPLICATIONS FOR REHABILITATIONKnee and hip osteoarthritis is a condition which is associated with an increased risk of cardiometabolic disease but also due to the low levels of physical activity and high levels of sedentary behaviour.Offsetting sedentary behaviour with light physical activity offers a feasible interventional target to reduce the risk of cardiometabolic disease in people with hip and knee osteoarthritis.