Association between patient-reported disease understanding assessed during rehabilitation and long-term outcomes in patients with knee osteoarthritis: a retrospective observational cohort study

Background Patient education is a core component of conservative management for knee osteoarthritis; however, patients’ understanding of their condition may change during rehabilitation as they receive repeated explanations and gain experience applying rehabilitation strategies in daily life. This study investigated whether patient-reported disease understanding assessed during rehabilitation was associated with 1-year clinical outcomes in patients with knee osteoarthritis. Methods This retrospective observational cohort study analyzed longitudinal clinical data collected during routine care from patients with knee osteoarthritis. Patient-reported disease understanding was assessed at baseline and 3 months, and clinical outcomes were evaluated using the Knee injury and Osteoarthritis Outcome Score (KOOS). The primary outcome was improvement in the KOOS5 composite score from baseline to 1 year, calculated as the arithmetic mean of the five KOOS subscale scores. Multiple linear regression analysis was performed to explore the association between patient-reported disease understanding and 1-year improvement in the KOOS5 composite score. Results In the primary multivariable model, greater patient-reported disease understanding at 3 months was positively associated with improvement in the KOOS5 composite score at 1 year, although the association was not statistically significant (B = 5.51, 95% CI − 1.20 to 12.23, P = 0.104). Adjustment for Kellgren–Lawrence grade produced a similar coefficient (B = 5.38), whereas additional adjustment for age attenuated the association (B = 4.46). The individual KOOS subscale analyses were considered exploratory; the nominally significant association observed for the Pain subscale was not statistically significant after correction for multiple comparisons. Conclusions Patient-reported disease understanding assessed at 3 months was positively associated with 1-year improvement in the KOOS5 composite score, although the association was not statistically significant. These exploratory findings should be considered hypothesis-generating and do not establish an independent or causal relationship between patient-reported disease understanding and clinical improvement. Larger prospective studies using validated measures of patient understanding are warranted. Clinical trial number Not applicable.