From Inflammation to Frailty: Investigating the Systemic Immunity-Inflammation Index in Older Patient

INTRODUCTION: Chronic inflammation is increasingly recognized as a crucial contributor to frailty pathogenesis, but accurate diagnosis remains a challenge. Aim Our study aims to investigate the relationship between frailty and the Systemic Immunity-Inflammation Index (SII, SIRI), a comprehensive indicator of inflammation.
METHODS: This cross-sectional study enrolled 200 patients. All participants underwent a comprehensive geriatric assessment. Frailty was assessed using the clinical frailty scale, (≥ 4; frail, <4 robust). 99 patients were included in the study as frail (Group 1) and 101 patients as robust (Group 2). To determine the SII, we used the formula: Platelet count×Neutrophil / Lymphocyte count. The calculation formula for SIRI is neutrophil count × monocyte count/Lymphocyte count.
RESULTS: The average age of the participants was 75.15 ± 8,8, and 55% (n=110) were female. Patients were grouped frail and robust. The frail group had 99 patients, while the robust group comprised 101 patients. Frail patients showed higher median SII and SIRI scores than the robust group(p < 0.001). Bınary logistic regression analysis revealed that the SII and SIRI scores were significantly and independently associated with frailty even after adjusting for potential confounding factors respectively (r =1.52, 95% CI= 1.189–1.964, p < 0.001, r=1.004, 95% CI=0.585-1.724, p=0.987). The ROC analysis identified the optimal cut-off for SII in predicting sarcopenia as > 596. At this threshold, the negative predictive values were determined to be 83.8%, with a specificity of 86%, cut-off for SIRI in predicting sarcopenia as > 1.1.
DISCUSSION AND CONCLUSION: The results of this cross-sectional study indicate a positive correlation between systemic inflammatory biomarkers (SII, SIRI) and frailty.