Associations between homocysteine, inflammatory cytokines and sarcopenia in Chinese older adults with type 2 diabetes

BACKGROUND: Sarcopenia, an age-related disease, has been implicated as both a cause and consequence of type 2 diabetes mellitus (T2DM) and a symbol of poor prognosis in older adults with T2DM. Therefore, early detection and effective treatment of sarcopenia are particularly important in older adults with T2DM. We aimed to investigate the prevalence of sarcopenia in Chinese older T2DM patients and explore whether homocysteine and inflammatory indexes could serve as biomarkers and participate in the development process of sarcopenia. METHODS: T2DM patients aged over 60 years were consecutively recruited from the ward of department of Endocrinology, Xuanwu Hospital between April 2017 and April 2019. Sarcopenia was defined based on the standard of the Asian Working Group of Sarcopenia, including muscle mass, grip strength and gait speed. Logistic regression was used to explore the association between biochemical indicators and sarcopenia. Receiver operating characteristic (ROC) curves were applied to determine the diagnostic effect of these clinical indicators. RESULTS: Totally 582 older adults with T2DM were characterized and analyzed in the study. Approximately 8.9% of the older T2DM patients had sarcopenia. After adjusting for age, sex, body mass index (BMI) and hemoglobin A1c (HbA1c), increased concentrations of homocysteine [odds ratio (OR): 2.829; 95% confidence interval (CI), 1.064–7.525] and high-sensitive C-reactive protein (hs-CRP) (OR: 1.021; 95% CI, 1.001–1.042) were independent predictors of sarcopenia; but not interleukin-6. The combination of age, sex, BMI and HbA1c provided a discriminatory effect of sarcopenia with an area under the curve (AUC) of 0.856, when homocysteine was added to the model, the value of the ROC curve was further improved, with an AUC of 0.861. CONCLUSION: In the current study, we demonstrated a positive correlation of homocysteine, hs-CRP with sarcopenia in older adults with T2DM and the relationship remained significant even after adjustment for HbA1c. These biomarkers (homocysteine and hs-CRP) may play important roles in the pathological process of sarcopenia.