Reference values of the dorsal muscle group area for the diagnosis of sarcopenia using chest computed tomography in patients with chronic obstructive pulmonary disease: A prospective observational study

BackgroundSarcopenia is common in patients with chronic obstructive pulmonary disease (COPD) and associated with poor prognosis. The dorsal muscle group area at the T12 vertebral level is useful in sarcopenia diagnosis; however, reference values for diagnosing sarcopenia are unavailable. This study aimed to establish the reference values for sarcopenia diagnosis using chest computed tomography scans in Japanese patients with chronic obstructive pulmonary disease. MethodsWe analyzed data from the Ishinomaki COPD Network Registry and selected the participants in the Ishinomaki COPD Network Registry who visited our hospital between April 2024 and March 2025. We investigated clinical parameters, including the dorsal muscle group area at the T12 vertebral level index (dorsal muscle group area at the T12 vertebral level/height2), to evaluate whether these parameters might serve as factors for sarcopenia. ResultsThis study included 353 patients. According to the sarcopenia status, the patients were divided into the sarcopenia and non-sarcopenia groups. Propensity score matching and multivariate analyses were performed to compare baseline characteristics between the two groups. Multivariate regression logistic models revealed that the dorsal muscle group area at the T12 vertebral level index was an independent factor for predicting sarcopenia in patients with chronic obstructive pulmonary disease. The area under the receiver operating characteristic curve for identifying sarcopenia in patients with chronic obstructive pulmonary disease was 0.71, and the optimal cut-off value of the dorsal muscle group area at the T12 vertebral level index was 8.39. ConclusionsOur study offers reference values for sarcopenia diagnosis using the dorsal muscle group area at the T12 vertebral level index evaluated using chest computed tomography in patients with chronic obstructive pulmonary disease. Identifying patients with chronic obstructive pulmonary disease in the early stages of sarcopenia can contribute to effective prevention and therapeutic measures.