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Association between TLR4 A299G polymorphism and pneumonia risk: a meta-analysis

Xingjun Cai1, Yihui Fu1, Qingyun Chen1

  • 1Department of Respiratory, Hainan Provincial People's Hospital, Haikou, Hainan, China (mainland).

Medical Science Monitor : International Medical Journal of Experimental and Clinical Research
|February 28, 2015
PubMed
Abstract

Insights

The Toll-like receptor 4 (TLR4) A299G polymorphism is linked to increased pneumonia risk. This meta-analysis confirms a significant association, particularly for community-acquired pneumonia (CAP).

Area of Science:

  • Genetics
  • Immunology
  • Infectious Diseases

Background:

  • Previous genetic studies on Toll-like receptor 4 (TLR4) A299G polymorphism and pneumonia risk yielded inconsistent results.
  • The TLR4 A299G polymorphism is a common single nucleotide polymorphism with potential implications for immune response.

Purpose of the Study:

  • To conduct a meta-analysis to clarify the association between TLR4 A299G polymorphism and pneumonia risk.
  • To consolidate findings from existing case-control studies to provide a more robust conclusion.

Main Methods:

  • Systematic literature search of major scientific databases (NCBI, Medline, Web of Science, Embase).
  • Inclusion of eight case-control studies comprising 658 pneumonia patients and 1862 controls.
  • Statistical analysis using odds ratios (ORs) and 95% confidence intervals (CIs) to assess the risk association.

Main Results:

  • The meta-analysis revealed a significant association between TLR4 A299G polymorphism and increased pneumonia risk (OR=1.74; 95% CI 1.19-2.53; P=0.004).
  • This association was significant in adult populations.
  • A notable association was also found with community-acquired pneumonia (CAP) risk.
  • Sensitivity and cumulative meta-analysis confirmed the reliability and robustness of the findings.

Conclusions:

  • The TLR4 A299G polymorphism is associated with an increased susceptibility to pneumonia.
  • This genetic variation may play a role in the host's defense against respiratory infections like CAP.

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