To understand potential pathways to study outcomes, we investigated relationships among EE markers and found LBP was not associated with either MPO or CRP, but MPO was positively associated with CRP in both HIV-uninfected (β = 0.20 (0.03, 0.37; P = 0.02)) and HIV-infected participants (β = 0.23(0.05, 0.43; P = 0.01)) (S3 Table). This evidence concerns the gene CRP and Low back pain.