The effects of TGF-β1 on IVDD were determined by MRI and histological analyses, and the effects of TGF-β1 on dorsal root ganglion (DRG) inflammation and pain development were determined by IHC staining and pain-behavior testing, respectively.
Linear regression models showed a significant positive correlation of pain with TGF-β1 (b = 770.91, p = 0.031) and a significant inverse correlation of pain with IL-33 (b = -0.11, p = 0.015) after controlling for age, gender, body mass index, lifetime depression, acute stress disorder symptoms, and the prognostic Global Registry of Acute Coronary Events (GRACE) score.
The correlation of IL-6 genotype with pain and the possible association of the TGF-beta1 codon 25 genotype with short-term radiographic damage (G/C with greater risk and G/G with decreased risk) suggests that both these polymorphisms may be useful early prognostic indicators.