Quality of life and self-reported disability in patients with knee osteoarthritis

Objectives Osteoarthritis (OA) is the most common degenerative joint disorder and a major public health problem throughout the world. The aims of this study are to assess quality of life (QoL) in patients with knee OA using the generic instrument Short Form-36 (SF-36) and to determine its relationships with conventional clinical measures and self-reported disability. Methods Patients with knee OA (n = 112) with median age of 60 (45-76) years and 40 sex-and age-matched healthy controls were included in the study. Age, sex, body mass index (BMI), symptom duration, and Kellgren-Lawrence scores were recorded. QoL, disability, and pain were assessed using the SF-36, the Western Ontario and McMaster (WOMAC) index, the Lequesne index, and a visual analog scale (VAS) in patients. Also, QoL was assessed using the SF-36 in controls. Results Patients with knee OA had lower scores in all subgroups of SF-36 compared with controls. In patients, the SF-36 physical function (PF) and pain areas significantly correlated with effusion, VAS pain, and Lequesne and WOMAC subgroup scores (p < 0.05). The pain area of QoL did not show correlation with comorbidity with knee OA. We found that SF-36 and WOMAC pain scores were more severe in female patients. Conclusions Patients with knee OA had significantly poorer QoL compared with healthy controls. SF-36 is related to the clinical status and functional ability of patients with OA and can be used as a sensitive health status measure for clinical evaluation. Also WOMAC can be used as a sensitive measure for disability of patients with knee OA.