In subjects with moderate and severe LBP, we identified four circulating miRNAs, including decreased concentrations of miR-146a and miR-558 and increased concentrations of miR-155 and miR-124a, which were strongly associated with measures of BMI, WHtR, muscle function, pain intensity, malnutrition, PA score, and other LBP-related biomarkers such as vitamin D status, TNF-α, IL-6, and CRP levels, and markers of bone metabolism (s-Ca, s-BAP, s-OC, and s-NTX). This evidence concerns the gene CRP and malnutrition.