Association between CILP and IL-1α polymorphisms and phenotype-dependent intervertebral disc degeneration susceptibility: A meta-analysis

Background: The relationship between CILP (1184T > C) and IL-1 alpha(+889C/T) polymorphisms and intervertebral disc degeneration (IDD) have been explored in several studies but the results were conflicting. The aim of the study was to evaluate and synthesize the currently available data on the association between CILP (1184T > C) and IL-1 alpha(+889C/T) polymorphisms and susceptibility of phenotype-dependent radiologic IDD (RIDD) and symptomatic intervertebral disk herniation (SIDH). Methods: A computerized literature search was in PubMed, Cochrane Library, Embase, China National Knowledge Infrastructure database, and Web of Science. The pooled results were presented as odds ratios (ORs) with 95% confidence intervals (CIs). Moreover, the false-positive report probability (FPRP) test and trial sequential analysis (TSA) were applied to estimate the significant results. Results: Our evidence demonstrated that IL-1 alpha(+889C/T) was significant associated with RIDD (allele model: OR = 1.34, 95%CI 1.03-1.74, p = 0.029) and SIDH (allele model: OR = 1.28, 95% CI 1.03-1.60, p = 0.028). However, the results were not noteworthy under the FPRP test and TSA analysis. Additionally, CILP (1184T > C) polymorphism was significantly associated with RIDD with adequate evidence (allele model: OR = 1.27, 95% CI 1.09-1.48, p = 0.002) instead of SIDH. Conclusion: The current meta-analysis illustrated firm evidence that CILP (1184T > C) polymorphism was significantly associated with the susceptibility of RIDD. However, the significant associations between IL-1 alpha(+889C/T) and RIDD and SIDH were less credible. Thus, more multi-center studies with diverse populations were required to verify the results.

Automated summary

This meta-analysis found significant associations between CILP (1184T > C) polymorphism and phenotype-dependent radiologic IDD, while the associations between IL-1 alpha (+889C/T) polymorphism and RIDD and SIDH were less credible.