Association between C-reactive protein-triglyceride glucose index and osteoarthritis in US adults: Evidence from NHANES (2017–2020)

This study aimed to explore the relationship between C-reactive protein-triglyceride glucose index (CTI) levels and osteoarthritis (OA) using cross-sectional data from the National Health and Nutrition Examination Survey conducted between 2017 and 2020. The analysis included 3885 individuals from the National Health and Nutrition Examination Survey 2017 to 2020 cohort. Multivariate logistic regression models, along with smoothed curve fitting techniques, were employed to assess the association between CTI and OA. In addition, subgroup analyses were performed to further investigate the relationship between CTI levels and OA. Of the 3885 participants, 515 (14.36%) had a diagnosis of OA. After adjusting for potential confounders, a positive association between CTI levels and OA incidence was observed (odds ratio = 1.3417, 95% confidence interval: 1.1409-1.5777, P = .0004). The highest quartile of CTI showed a significant increase in OA risk (odds ratio = 1.5369, 95% confidence interval: 1.0605-2.2352, P = .0237), with the lowest quartile serving as the reference group. Smooth curve fitting analysis revealed a nonlinear positive correlation between CTI and OA prevalence, with a potentially key inflection point at a CTI value of 10.4266. Subgroup analyses indicated that the educational level was the only variable where a significant interaction between CTI and OA was found (P for interaction = .03). Our findings suggest a significant positive association between CTI levels and OA risk, with a critical threshold identified at 10.4266, which may hold clinical relevance for predicting OA risk. This study underscores the potential of CTI as an innovative, easily accessible inflammatory biomarker for assessing OA risk in adults. However, further prospective studies are required to confirm a causal relationship between CTI and OA.