The Relationship Between Pain and Quality of Life Among Adults With Knee Osteoarthritis: The Mediating Effects of Lower Extremity Functional Status and Depression.

Pain, lower extremity functional status, and depression have been associated with quality of life among patients with knee osteoarthritis (KOA). However, little is known about the manner in which these factors influence quality of life. The present study examined the mediating effects of lower extremity functional status and depression on the relationship between pain and quality of life among adults with KOA. A descriptive cross-sectional study was conducted among 135 adults with KOA who visited an orthopaedic outpatient clinic in Korea. The participants responded to the Numeric Rating Scale, Lower Extremity Functional Scale, Beck Depression Inventory, and the Korean version of the World Health Organization Quality of Life-BREF. Mediation analysis was conducted using the PROCESS macro for SPSS. The serial mediating effects of lower extremity functional status and depression on the relationship between pain and quality of life were significant. These findings suggest that the assessment and management of lower extremity functional status and depression are important means by which the quality of life of adults with painful KOA can be improved.