The relationship between restless sleep and symptoms of the knee: data from the Osteoarthritis Initiative.

While the analysis of cross-sectional data supported the association between restless sleep and KOA symptoms, such relationships were not confirmed in more robust longitudinal analysis. Further research examining whether sleep quality, duration, or disorders is associated with worsening symptoms in persons with KOA is warranted. Key Points • The prevalence of frequent restless sleep among persons with knee OA is not uncommon. • There were linear trends between frequency of restless sleep and self-reported symptoms of the knee in cross-sectional analyses. • In the more robust longitudinal analysis, despite the statistically significant linear trends observed between frequency of restless sleep and symptoms (women: pain and physical function; men: function), none appeared to reach the a priori selected ranges for minimally clinically relevant differences.