Abstract
BACKGROUND: Population-based studies exploring the association between sarcopenia, possible sarcopenia and Knee Osteoarthritis (KOA) ‒ particularly including the intermediate state of possible sarcopenia ‒ remain limited. The authors aimed to explore both cross-sectional and longitudinal associations between possible sarcopenia, sarcopenia, and KOA in a large cohort of Chinese adults. METHODS: The authors utilized data from the China Health and Retirement Longitudinal Study. After applying the exclusion criteria, a total of 5018 participants aged 45-years or older were included and followed from 2011 to 2015. Sarcopenia status was classified as non-sarcopenia, possible sarcopenia, or sarcopenia according to the Asian Working Group for Sarcopenia. Logistic regression was used to assess the associations between sarcopenia status and KOA, including associations with changes in sarcopenia status over follow-up. RESULTS: Sarcopenia and possible sarcopenia demonstrated a significant positive association with KOA, exhibiting an Odds Ratio (OR) of 1.37 (95% CI: 1.02‒1.83) and an OR of 1.55 (95% CI: 1.26‒1.91), respectively. Participants who newly developed sarcopenia had an increased likelihood of developing KOA than those who remained non-sarcopenic, with an OR of 1.72 (95% CI: 1.27‒2.32). The incidence of KOA differed significantly among the non-sarcopenia, possible sarcopenia, and sarcopenia groups, with rates of 10.0% in the non-sarcopenia group, 17.8% in the possible sarcopenia group, and 16.1% in the sarcopenia group (p-value < 0.01). CONCLUSIONS: Sarcopenia and possible sarcopenia were associated with the occurrence of KOA. Individuals who newly developed sarcopenia or possible sarcopenia were at a higher risk of developing KOA during the four-year follow-up.