title: Elevated interleukin-6 expression levels are associated with intervertebral disc degeneration.
abstract: The present study aimed to investigate whether serum interleukin-6 (IL-6) expression levels were associated with the onset and progression of intervertebral disc degeneration (IDD). A comprehensive meta-analysis of the scientific literature from numerous electronic databases was performed, in order to obtain published studies associated with the topic of interest. Relevant case-control studies that had previously assessed a correlation between IL-6 expression levels and IDD were identified using predetermined inclusion and exclusion criteria. The STATA version 12.0 software was used for statistical analysis of the extracted data. A total of 112 studies were initially retrieved, with eight studies meeting the inclusion criteria. These contained a total of 392 subjects, of which 263 were patients with IDD and 129 were healthy controls. A meta-analysis of the eight studies demonstrated that serum IL-6 protein expression levels may be associated with IDD, and this was irrespective of IDD subtype (bulging, protrusion, or sequestration). Notably, serum expression levels of the IL-6 protein were upregulated in intervertebral disc (IVD) protrusion tissue, as compared with normal IVD tissue; thus suggesting that IL-6 may have an important role in the pathophysiological process of IDD.
authors.affiliation: Department of Orthopedics, Shaanxi Sengong Hospital, Xi'an, Shaanxi 710300, P.R. China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Deng
authors.affiliation: Department of Orthopedics, Shaanxi Sengong Hospital, Xi'an, Shaanxi 710300, P.R. China.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
authors.affiliation: Department of Orthopedics, Shaanxi Sengong Hospital, Xi'an, Shaanxi 710300, P.R. China.
authors.forename: Baolin
authors.initials: B
authors.lastname: Kang
authors.affiliation: Department of Orthopedics, Shaanxi Sengong Hospital, Xi'an, Shaanxi 710300, P.R. China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhang
keywords: interleukin-6; intervertebral disc; intervertebral disc degeneration; meta-analysis