Associations of Physical Activity, Sedentary Behaviour, Pain, Function and Quality of Life With Diabetes and Knee Osteoarthritis: Data From the Osteoarthritis Initiative.

Objective: To investigate the relation of radiographic knee osteoarthritis (RKOA) and type 2 diabetes mellitus (T2DM) to physical activity, pain, physical function, and quality of life.

Methods: Data on physical activity (light and moderate-vigorous physical activity minutes/day, steps/day, sedentary time percent of wear time), pain, physical function (Western Ontario and McMaster Index, walking speed during 20-m walk) and quality of life (SF-12) from the Osteoarthritis Initiative at the 48-month visit were included. Participants (n = 1788) were categorised into no RKOA or T2DM, RKOA-alone, T2DM-alone, and RKOA and T2DM. Multivariable regression models, adjusted for age, sex, and BMI, assessed the relationship of disease status to outcomes.

Results: Compared to RKOA-alone, RKOA and T2DM were associated with lower moderate-vigorous physical activity (Coefficient: 4 min/day, 95% CI: [-7, -1]) and steps/day (-817 steps/day [-1291, -343]) and higher sedentary time percent (1.3%/day [-0.2, 2.8]). No significant differences were found in light physical activity (-11 min/day [-25, 2]). The RKOA and T2DM groups reported greater pain (1.0 [0.4, 1.6]) and functional limitations (3 [1, 5]), slower walking speed (-0.09 m/s [-0.12, -0.05]), and worse quality of life (-3.2 [-4.8, -1.6]). T2DM-alone was also associated with lower physical activity and worse quality of life than RKOA-alone.

Conclusions: The comorbidity of RKOA and T2DM and T2DM-alone were associated with lower physical activity and worse quality of life than RKOA-alone. Management should address both conditions concurrently rather than in isolation.