Inflammatory mediators, muscle and functional performance of community-dwelling elderly women

The purpose of this study was to investigate the correlation and association between inflammatory mediators and muscle and functional performance in elderly women. We conducted a cross-sectional study. Plasma concentrations of interleukin-6 (IL-6) and soluble receptor for tumor necrosis factor alpha (sTNFR1) were determined by enzyme-linked immune sorbent assay. The muscle performance was measured using a isokinetic dynamometer and assessment of handgrip strength was performed using a Jamar® dynamometer. Functional performance was assessed through a walking speed test. Statistical analysis was performed using the Pearson or Spearman correlation. The association between the variables was determined by multiple regression analysis. 221 volunteers (71.07±4.93 years) participated in the study. Plasma levels of IL-6 (0.87pg/mL) correlated with the power of the knee extensors (r=0.14; p=0.03) and the power of the knee flexors (r=0.16; p=0.01); the plasma levels of sTNFR1 (1051.70pg/mL) did not correlate with any dependent variable. The regression models showed that the variables IL-6, level of physical activity and depressive status explained 5.5% (R(2)=0.055, p<0.01) of average power of knee extensors variability. For the average power of knee flexors, the final model showed that the factors IL-6 and level of physical activity explained 4.1% (R(2)=0.041, p<0.01). There was no negative correlation between inflammatory mediators and muscle or physical performance in elderly women. These results may be explained by the fact that the cytokine levels did not reach the threshold needed to influence the muscle tissue and functionality of the participants.