The association between sarcopenia and diabetic retinopathy: a mediation analysis of inflammatory biomarkers

Background Sarcopenia represents a crucial risk factor for diabetic retinopathy (DR). This study is to investigate the association between sarcopenia and DR in patients with type 2 diabetes mellitus (T2DM) and to examine the mediating role of inflammatory biomarkers. Methods Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019. DR was based on ophthalmologic examination. The inflammatory biomarkers included the neutrophil-percentage-to-albumin ratio (NPAR), advanced lung cancer inflammation index (ALI) and pan-immune-inflammation value (PIV). Logistic regression and mediation analyses were conducted to evaluate the associations among sarcopenia, inflammatory biomarkers, and DR and the mediating effects of the biomarkers. Results 749 participants were included in the analysis. The prevalence of DR was 25.0% and sarcopenia was associated with DR (adjusted odds ratio ( aOR ):1.61, 95% confidence level ( CI ): 1.14-2.26). NPAR, ALI and PIV statistically accounted for this association, explaining 13.44%, 10.41%, and 10.77% of the effect, respectively. Conclusions Sarcopenia is an independent associated factor for DR in T2DM. NPAR, ALI and PIV play a partial role in this association. These blood-cell-based inflammatory biomarkers are associated with DR, but their role in clinical screening remains to be determined.