Inflammatory and anti-inflammatory biomarkers in frailty elderly and the association with sarcopenia

Abstract

Frailty and sarcopenia are multifactorial geriatric syndromes, very prevalent among the older population and share adverse outcomes, such as increased risk for disability, institutionalization and death. Despite a possible inflammatory pathophysiological pathway, common to both disorders, it has been little explored in the literature, limited to a few common cytokines. Thus, it is important to expand the investigation of pro-inflammatory and especially anti-inflammatory biomarkers together, as well as to understand the association of sarcopenia to chronic low-grade inflammation in frail and pre-frail elderly people, being a potential mediating variable for physical frailty. The objectives of this study are to compare the levels of pro-inflammatory and anti-inflammatory biomarkers in frail, pre-frail and robust older adults and, in each group, to compare the inflammatory profile between seniors with and without sarcopenia and to verify the association between serum levels of pro-inflammatory and anti-inflammatory biomarkers with sarcopenia and its components (muscle strength, muscle mass and physical performance). A total of 300 older adults will be evaluated in baseline and after 12 months of follow-up. Frailty will be classified according to the phenotypic model and all participants will be submitted to the assessment of serum levels of pro-inflammatory (IL-6, TNF-alpha, IL1beta, IL-17, IL-22 and CXCL-8) and anti-inflammatory (IL-1ra and IL-27) interleukins (IL). In addition, participants will be assessed for sarcopenia according to the updated criteria of the European Working Group on Sarcopenia in Older People (EWGSOP2). Interleukins, as well as the criteria for frailty and sarcopenia, will be assessed at baseline and outcomes such as transitions of the frailty and sarcopenia status, falls, hospitalization or death will be evaluated in 12 months. The intergroup analysis (Frail, Pre-Frail and Robust) of the inflammatory profile will be performed using one-way ANOVA or Kruskall Wallis test. The association between serum levels of pro-inflammatory and anti-inflammatory cytokines and the presence of sarcopenia, muscle strength, muscle mass and physical performance will be tested using the logistic and linear regression models. For all analyzes, a significance level of 0.05 (pd 0.05) will be adopted. The results of the present study will help to better understand the relationship between inflammation, frailty and sarcopenia, in addition to potential guidance for the monitoring and detection of frailty and sarcopenia syndrome using biomarkers of the inflammatory cascade. To the best of our knowledge this combined analysis of inflammatory and anti-inflammatory IL was never performed. (AU)