Analysis of potential biomarkers and risk factors for rheumatoid arthritis with sarcopenia-osteomalacia based on 1H NMR technique: a case-control study

This study investigated metabolic network disparities in serum between individuals with rheumatoid arthritis (RA) alone and those with RA and concurrent sarcopenia-bone metabolism abnormalities (RA-OP), correlating these findings with clinical observations to identify potential risk factors for complications. Serum metabolites from 40 patients in the RA-OP group and 24 in the RA group were analyzed. Biomarkers were identified using pattern recognition and multivariate statistics. The levels of IGF-1, vitamin D, bone metabolism indices, and physical measurements were assessed, and correlation analyses were performed to explore the relationships. The RA-OP group exhibited higher disease duration, activity, and physical function assessments compared to the RA-only group (P < 0.05). ROC curve analysis suggested that bone metabolism indicators (C-terminal telopeptide (CTX), procollagen type 1 N-terminal propeptide (PINP), vitamin D, osteocalcin (OST), and insulin-like growth factor 1 (IGF-1)) might serve as early screening markers. Metabolomic analysis identified 42 differential products and 12 significant metabolic pathways, with 13 potential biomarkers revealed by receiver operating characteristic (ROC) curves. RA-OP impacts balance and mobility; increases fall risk; and is associated with bone metabolic indices, disease duration, activity, and hormones. Metabolic network abnormalities may disrupt glucose, lipid, and amino acid metabolism, affecting reactive oxygen species (ROS) metabolism and involving multiple pathways.