To evaluate the health-related quality of life (HRQoL) of knee osteoarthritis (KOA) patients in China, compare their HRQoL with norm population, and examine the associations between the potential influencing factors and HRQoL.
A cross-sectional study was conducted in 912 KOA patients from 4 provinces between March and November 2017. All participants were diagnosed according to the National Institute for Health and Care Excellence (NICE)'s criterion or the Chinese Medical Association (CMA)'s criterion. Recruited patients were surveyed for HRQoL using the 12-item Short Form (SF-12) and sociodemographic, disease-related factors. We assessed the associations between potential influencing factors and HRQoL using multiple linear regression models.
Among the KOA patients, the mean physical component summary (PCS) of HRQoL was 40.91 ± 11.62, lower than norm (P < 0.001). And the mean mental component summary (MCS) was 50.25 ± 11.99, similar to the norm. Patients who were older (β = - 0.155, P = 0.001), women (β =  - 4.589, P < 0.001), had ever been treated (β =  - 2.426, P = 0.006), had longer course of KOA (β =  - 0.164, P = 0.012), and were in early stage (β =  - 2.968, P = 0.001) or progressive/late stage (β =  - 7.636, P < 0.001) showed lower scores of PCS. Patients who lived in Hunan (β = 4.988, P < 0.001) and had education levels of junior high school (β = 3.134, P = 0.012) or senior high school and above (β = 3.050, P = 0.010) had better mental status. Those suffered from non-knee pains (β =  - 2.308, P = 0.027) and with progressive or late KOA (β =  - 4.690, P = 0.016) had lower MCS scores.
KOA patients had worse physical condition. The mental and physical health of patients were affected by different factors. Targeted management measures should be taken to improve their HRQoL.